This document provides information about urodynamic evaluation of voiding dysfunction. It discusses the history of urodynamics, aims, equipment used including catheters, flowmeters and EMG equipment. It describes how to conduct urodynamic evaluations including uroflowmetry, cystometrogram, and considerations for filling rate and medium. Key points covered are the indications for urodynamics, preparation of patients, types of equipment and how to interpret uroflow curves and cystometrogram measurements.
The surgical treatment of an injury or defect within the urethra's walls is known as urethroplasty. The three most frequent factors leading to urethral damage that needs to be repaired are trauma, iatrogenic injury, and infections. The gold standard treatment for urethral strictures is urethroplasty, which has a lower recurrence rate than dilatations and urethrotomies. Although recurrence rates are higher for this challenging treatment group, it is likely the only effective treatment option for chronic and severe strictures.
Urethroplasty is not regarded as a small procedure, taking three to eight hours on average in the operating room. Between 20% and 30% of urethroplasty patients may benefit from the ease of going under the knife for a shorter period of time and going home the same day. On average, hospital stays last two to three days. Seven to ten days may be needed for hospitalization for more complicated surgeries.
Fewer than ten percent of patients experience significant complications after urethroplasty, while complications, particularly recurrences, are more frequent in long and complex strictures.
In absence of standardised criteria diagnosis of lower urinary tract dysfunction is difficult in women. Comprehensive urodynamics including pressure-flow study, urethral pressure profilometry, EMG as well as video coordination (or separately done MCUG) are often required. pelvic floor dysfunction (so called dysfunctional voiding), bladder neck obstruction and urethral stricture are differential diagnoses. initial treatment of dysfunctional voiding includes behavioural modification, pelvic floor relaxation exercises, medications, treatment of constipation. further treatment includes inj Botox into sphincter and sacral neuromodulation.
Dr Ho Siew Hong shared his experience on how to perform the ideal puncture for PCNL in a lecture to Asian urologists during the Advanced Urology Course 2008 in Singapore
HoLEP: the gold standard for the surgical management of BPH in the 21st CenturyDr. Manjul Maurya
HoLEP is at least as effective as other surgical therapies, including TURP, OP and other laser modalities, with fewer complications, shorter hospital stays, and decreased catheter time. These benefits make HoLEP the procedure of choice for men seeking surgical relief for BPH related LUTS and the gold standard for the 21st Century.
Uretero-Enteric Anastomosis Stricture after Urinary Diversion; Detailed Analy...JohnJulie1
To report the lessons we have learned in the management of uretero-enteric anastomosis stricture (UEAS) in a tertiary urology center over a decade of experience.
The surgical treatment of an injury or defect within the urethra's walls is known as urethroplasty. The three most frequent factors leading to urethral damage that needs to be repaired are trauma, iatrogenic injury, and infections. The gold standard treatment for urethral strictures is urethroplasty, which has a lower recurrence rate than dilatations and urethrotomies. Although recurrence rates are higher for this challenging treatment group, it is likely the only effective treatment option for chronic and severe strictures.
Urethroplasty is not regarded as a small procedure, taking three to eight hours on average in the operating room. Between 20% and 30% of urethroplasty patients may benefit from the ease of going under the knife for a shorter period of time and going home the same day. On average, hospital stays last two to three days. Seven to ten days may be needed for hospitalization for more complicated surgeries.
Fewer than ten percent of patients experience significant complications after urethroplasty, while complications, particularly recurrences, are more frequent in long and complex strictures.
In absence of standardised criteria diagnosis of lower urinary tract dysfunction is difficult in women. Comprehensive urodynamics including pressure-flow study, urethral pressure profilometry, EMG as well as video coordination (or separately done MCUG) are often required. pelvic floor dysfunction (so called dysfunctional voiding), bladder neck obstruction and urethral stricture are differential diagnoses. initial treatment of dysfunctional voiding includes behavioural modification, pelvic floor relaxation exercises, medications, treatment of constipation. further treatment includes inj Botox into sphincter and sacral neuromodulation.
Dr Ho Siew Hong shared his experience on how to perform the ideal puncture for PCNL in a lecture to Asian urologists during the Advanced Urology Course 2008 in Singapore
HoLEP: the gold standard for the surgical management of BPH in the 21st CenturyDr. Manjul Maurya
HoLEP is at least as effective as other surgical therapies, including TURP, OP and other laser modalities, with fewer complications, shorter hospital stays, and decreased catheter time. These benefits make HoLEP the procedure of choice for men seeking surgical relief for BPH related LUTS and the gold standard for the 21st Century.
Uretero-Enteric Anastomosis Stricture after Urinary Diversion; Detailed Analy...JohnJulie1
To report the lessons we have learned in the management of uretero-enteric anastomosis stricture (UEAS) in a tertiary urology center over a decade of experience.
Uretero-Enteric Anastomosis Stricture after Urinary Diversion; Detailed Analy...NainaAnon
To report the lessons we have learned in the management of uretero-enteric anastomosis stricture (UEAS) in a tertiary urology center over a decade of experience.
This product discuss Hirschsprung’s disease in pediatrics included [pathology, presentation, diagnostic tools, surgical procedures complications and management. Also discuss the recent concepts of management of post operative complications.
Dr Pawan Sharma1*, Dr D K Verma2, Dr Raj Kumar3
1General Surgeon Incharge, Civil Hospital Rohru, Shimla (HP), India
2Professor of Surgery, IGMC Shimla (HP), India
3General Surgeon Incharge, Distt Hospital Bilaspur (HP), India
*Address for Correspondence: Dr. Pawan Sharma, General Surgeon Incharge, Department of Surgery, Civil Hospital,
Rohru, Shimla, HP, India
Received: 17 September 2016/Revised: 11 October 2016/Accepted: 25 October 2016
ABSTRACT- This study was carried out to evaluate laparoscopic retroperitoneal ureterolithotomy (RPUL) as a viable
option to open surgical ureterolithotomy, laparoscopic transperitoneal ureterolithotomy (TPUL) & endoscopic urology and
to assess its place in the spectrum of alternatives for the surgical treatment of ureteric calculi in a tertiary care centre. This
study was conducted on 20 selected patients of single large impacted calculus of size more than 8mm in upper & middle
ureter. It was observed that excessive bleeding was present in only one (5%) of the patients, while need for conversion to
open ureterolithotomy was seen in 8 (40%) cases. No major peri-operative complications were encountered. From our
experience, it can be concluded that this procedure has definitely shown decreased post-operative discomfort, decreased
requirement of post-operative analgesia, better cosmesis, early return to work and less morbidity. RPUL can be considered
as another well-established armamentarium in the armour of laparoscopic surgeons and is recommended as an effective
minimally invasive primary treatment in large, impacted difficult stones in the upper & mid ureter.
Key-words- Retroperitoneal ureterolithotomy (RPUL), Transperitoneal ureterolithotomy (TPUL), Extracorporeal
shockwave lithotripsy (ESWL)
International Journal of Pharmaceutical Science Invention (IJPSI)inventionjournals
International Journal of Pharmaceutical Science Invention (IJPSI) is an international journal intended for professionals and researchers in all fields of Pahrmaceutical Science. IJPSI publishes research articles and reviews within the whole field Pharmacy and Pharmaceutical Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
COMPARATIVE STUDY BETWEEN LAPAROSCOPIC AND OPEN CHOLECYSTECTOMY (STUDY OF 50 ...KETAN VAGHOLKAR
Background: Laparoscopic cholecystectomy is a new alternative to the traditional open approach for
treating calculous cholecystitis. It is, therefore, necessary to assess the efficacy of laparoscopic cholecystectomy over the
open cholecystectomy. Objectives: To compare the surgical outcomes of laparoscopic cholecystectomy with those of open
cholecystectomy. Materials and methods: 50 patients diagnosed as symptomatic cholelithiasis proven by radiological
investigations were distributed into two groups of 25 each. Group A patients were subjected to laparoscopic cholecystectomy, and group B patients underwent open cholecystectomy. The surgical outcomes were studied prospectively.
Intraoperative complications and postoperative care parameters were evaluated. Results: Mean age of patients in group
A was 46.68±13.6 years, and in the group, B was 42.64±14.1 years. Majority of patients were in the age group of 41 to 60
years. Patients who had diabetes in group B developed wound infections, whereas diabetic patients in group A did not
develop any infection. Significant bleeding necessitating blood transfusion occurred in one patient belonging to group B.
The duration of postoperative analgesia required was 3.16 days in group A and 5.16 days in group B. The duration of
postoperative antibiotics administered in laparoscopic and open cases was 1.48 and 4.8 days, respectively. One of the
patients in group A developed a postoperative biliary leak, whereas none in group B had any such complication. The
commencement of oral feeds and after that return of bowel movements was earlier in group A than group B. The mean
hospital stay was 4.5 days in group A as compared to 6.3 days in group B. Conclusion: Laparoscopic cholecystectomy
is superior to open cholecystectomy regarding reduced postoperative discomfort and pain, antibiotic and analgesic
requirement, early commencement of oral feeds, and shorter duration of hospitalization
The presentation gives an Overview of ROSS operation and delves in to depth in 3 key areas as follows:
1. Our experience
2. Special situations
3. RVOT Reconstruction with xenografts
With an experience over 2 decades as a radiologist, Dr. Parag Vora has dedicated 10 years of his service at Canada’s Mcmaster university at Burlington, Hamilton. This case study focuses on computed tomography associated with operative management for non strangulating small bowel obstruction. The experienced team behind this elaborative bowel study included Dr. Rakesh. R. Suri, Dr. Parag Vora, Dr. John. M. Kirby and Dr. Leyo Ruo.
Have a look at my blog, here I discussed about my medical experience and what all have been keeping me busy.
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Ureteric stent versus percutaneous nephrostomy for acute ureteral obstruction - clinical outcome and quality of life: a bi-center prospective study
Urology Journal Club
LAPAROSCOPIC VERSUS OPEN APPENDICECTOMY IN ADULTS. (STUDY OF 50 CASES)KETAN VAGHOLKAR
Background: Appendicectomy is one of the common procedures performed by a general surgeon. However,
the advent of laparoscopic appendicectomy has reduced the number of open appendicectomies performed. Therefore
there is a need to study the advantages of the laparoscopic approach over the traditional open approach. Aims: The
study aimed to compare laparoscopic appendicectomy with open appendicectomy based on various intraoperative and
postoperative parameters Materials and methods: 50 patients undergoing interval appendicectomy were randomised
into two groups. Group A comprised 25 patients who underwent laparoscopic appendicectomy and group B comprised
25 patients who underwent open appendicectomy. Results: Confirmation of diagnosis and evaluation of intraoperative
findings was easier in group A patients. In addition, early commencement of feeds with early bowel movements, reduced
need for postoperative analgesia due to less pain, lesser complications and shorter duration of hospital stay was observed
in group A patients. Conclusion: Laparoscopic appendicectomy has better outcomes rendering it a preferable procedure
for appendicectomy.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
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These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
1. Latha .G
Urodynamic Evaluation of
Voiding Dysfunction
Dept of Urology
Govt Royapettah Hospital and Kilpauk Medical College
Chennai
2. Moderators:
Professors:
Prof. Dr. G. Sivasankar, M.S., M.Ch.,
Prof. Dr. A. Senthilvel, M.S., M.Ch.,
Asst Professors:
Dr. J. Sivabalan, M.S., M.Ch.,
Dr. R. Bhargavi, M.S., M.Ch.,
Dr. S. Raju, M.S., M.Ch.,
Dr. K. Muthurathinam, M.S., M.Ch.,
Dr. D. Tamilselvan, M.S., M.Ch.,
Dr. K. Senthilkumar, M.S., M.Ch.
Dept of Urology, GRH and KMC, Chennai. 2
3. History
Urodynamics was first defined by David M. Davis in 1953
The study of the storage and emptying phases of the
urinary bladder ( Davis, 1953 ).
The cystometrograph, introduced in 1927 by D. K. Rose, was one
of the earliest urodynamic instruments for measuring bladder
pressure during filling and voiding ( Rose, 1927 ).
This was followed by the uroflowmeter by Drake in 1948 .
In the 1950s, the development of simultaneous radiographic
imaging done in conjunction with physiologic studies was
pioneered by Hinman and Miller ( Hinman et al, 1954 ).
3
Dept of Urology, GRH and KMC, Chennai.
4. Today, the urodynamic armamentarium is
uroflowmetry and
cystometry as well as
pressure-flow studies,
electrophysiologic studies,
urethral pressure studies, and
videourodynamic studies.
4
Dept of Urology, GRH and KMC, Chennai.
5. Nitti noted three important principles in
urodynamics:
(1) a study that does not duplicate the patient's
symptoms is not diagnostic,
(2) failure to record an abnormality does not rule
out its existence, and
(3) not all abnormalities detected are clinically
significant ( Nitti and Combs, 1998 ).
5
Dept of Urology, GRH and KMC, Chennai.
6. Aim of urodynamics
The aim of clinical urodynamics is to
reproduce symptoms while making precise
measurements of the bladder physiology.
6
Dept of Urology, GRH and KMC, Chennai.
7. Indications and Selection of Patients for Conduction of
Urodynamics
I. Patients in whom potential therapy may be hazardous where one
would want to be sure of the correct diagnosis before instituting
therapy
II. Patients with recurrent incontinence in whom surgery is planned
III. Patients with incontinence and a confusing mix of stress and urge
symptoms and those with associated voiding problems
IV. Patients with neurologic disorders and those with a mismatch
between symptoms and clinical findings
Patients with LUTS suggestive of bladder outlet obstruction
7
Dept of Urology, GRH and KMC, Chennai.
8. V. Patients with LUTS who have both obstructive and marked
instability symptoms
VI. Patients with obstructive LUTS and neurologic disease
Young men with LUTS
VII. All neurologically impaired patients who have neurogenic
bladder dysfunction
VIII. Children with daytime urgency and urge incontinence
IX. Children with persistent diurnal enuresis
X. Children with spinal dysraphism
8
Dept of Urology, GRH and KMC, Chennai.
9. PREPARATION OF PATIENTS AND
PRECAUTIONS
prestudy discussion of the study technique and
counseling about the risks are appropriate
During the study, the patient should understand what
information we are trying to collect sufficiently to be
able to volunteer timely responses to changing events.
Some may have been started empirically on medication
for their symptoms including anticholinergics, α
blockers, bladder relaxation medications, and
psychotropic medications. These affect urodynamic
outcomes and should be stopped with an adequate
washout period prior to the test.
9
Dept of Urology, GRH and KMC, Chennai.
10. An adequate history and physical examination
should be performed before the test and
a voiding diary completed to determine the
functional capacity, daily urine output, and
approximate filling volume
10
Dept of Urology, GRH and KMC, Chennai.
11. Antibiotics
Pretest urinalysis is negative for infection
Parenteral antibiotic prophylaxis may be necessary in
specific patients, such as those with cardiac valve
abnormalities, orthopedic prostheses, genitourinary
prostheses, pacemakers, and other electrical devices
patients with total joint replacements within 2 years
after implant surgery, immunocompromised patients,
and those with previous prosthetic joint infections (
American Urological Association Advisory Statement,
2002 ).
11
Dept of Urology, GRH and KMC, Chennai.
12. The Urodynamics Room
The room used for urodynamics should be without
distractions, quiet, and protected from unnecessary
interruptions.
The room should be large enough for the physician
to perform a physical and pelvic examination,
to place catheters, and
to move unencumbered within the room.
One should always take into account the need for
sufficient room to allow for wheelchairs and assist
devices such as walkers.
12
Dept of Urology, GRH and KMC, Chennai.
13. URODYNAMIC EQUIPMENT
Three measurement
channels,
two for pressure and
one for flow;
a display (on either a
printer or a monitor); and
a method for secure
storage of the recorded
pressures (abdominal,
vesicle, detrusor) and
flow measurements as
tracings against time (
Schafer et al, 2002 ).
13
Dept of Urology, GRH and KMC, Chennai.
14. The infused volume and voided volume may be recorded
graphically or numerically.
all measured and derived signals must be displayed
continuously over time according to ICS standards,
preferably with the following sequential position of
tracings:
from top down on the page
Pabd (abdominal pressure),
Pves (vesical pressure),
Pdet (detrusor pressure), and
flow (Q).
Filling volume,
electromyography (EMG), and
voided volumes may be displayed.
14
Dept of Urology, GRH and KMC, Chennai.
15. Catheters
The standard catheter for routine urodynamics is a
transurethral, double-lumen catheter .
Suprapubic placement has been used in patients with
obstruction such as urethral stricture disease,
The smallest available is the 6 Fr double-lumen
catheter.
This allows the fill and void sequence to be repeated
without recatheterization.
similarly sized triple-lumen catheters are available
that allow bladder filling, intravesical pressure
measurement, and urethral pressure recording.
15
Dept of Urology, GRH and KMC, Chennai.
16. The use of a balloon catheter is best for the
measurement of abdominal pressure.
An air-free balloon in the rectum or in the vagina
in women.
The balloon maintains a small fluid volume at the
catheter opening to avoid fecal blockage
preventing pressure transmission.
16
Dept of Urology, GRH and KMC, Chennai.
17. Flowmeters
The flow rate is measured by a uroflowmeter with the
SI unit for flow being cubic meters per second
(m3/sec) and for mass flow rate kilograms per second
(kg/sec)
Most flow rates are reported in milliliters per second
(mL/sec) .
Most flowmeters are calibrated for water, which has a
density of 1; therefore, the mass of the fluid in grams
equals the volume in milliliters.
17
Dept of Urology, GRH and KMC, Chennai.
18. Urodynamics Equations
1. Flow rate:
Flow is the change in volume over the change in time: q = dV/dt:
flow rate (Q), volume (V), time (T),
2. Compliance:
C (compliance) = dV/dPdet (detrusor pressure).
3. Detrusor pressure:
pdet = pves - pabd,
pdet (detrusor pressure), pves (vesical pressure), pabd (abdominal
pressure).
4. Physiologic filling rate for cystometry:
rate = body weight (in kg)/4, expressed as mL/min.
18
Dept of Urology, GRH and KMC, Chennai.
19. Types of Flowmeter
Gravimetric flowmeters operate by measuring the weight of the
collected fluid or by measuring the hydrostatic pressure at the
base of the collecting cylinder.
The electronic dip stick flowmeter measures the electrical
capacitance of a dipstick mounted in a collecting chamber.
In the rotating disk flowmeter the voided fluid is directed onto a
rotating disk. The power required to keep the disk rotating at a
constant rate is measured and proportional to the mass flow rate
of the fluid.
Today, most available flowmeters are gravimetric or rotating disk
transducers. 19
Dept of Urology, GRH and KMC, Chennai.
20. Electromyography Equipment
EMG is the study of the electrical potentials produced
by the depolarization of muscle membranes.
The depolarization must first be detected by an
electrode placed close to the origin of the signal.
These include intramuscular needle electrodes and
surface electrodes placed on the skin or mucosa
overlying the muscle of interest.
20
Dept of Urology, GRH and KMC, Chennai.
21. Types of Electrodes
Self-adhesive, skin patch electrodes provide good surface recordings and
allow patients mobility. These electrodes are predominantly used in
pediatric urodynamics.
Needle electrodes provide better recording quality and specificity for
certain muscle groups.
Wire electrodes are made of stainless steel, platinum, or copper wire. The
wire is placed into the muscle to be studied through a needle acting as a
cannula.
Monopolar electrodes are thin needles coated with an insulating
material with an exposed tip. They need a reference electrode, a small
metal disk attached to the skin near the muscle being examined.
Concentric electrodes consist of a wire inside an outercannula,
separated by insulating material. The outer, conductive portion serves as
the ground. This can record from one to three motor units
simultaneously.
21
Dept of Urology, GRH and KMC, Chennai.
23. Uroflow
Uroflowmetry is noninvasive, inexpensive, and
invaluable in screening patients with voiding
dysfunction.
This noninvasive test should precede any other
urodynamic studies.
It is easy to perform and quickly provides data on both
storage and voiding symptoms.
Ideally, two or more tests should be performed, and
the addition of a noninvasive postvoid residual volume
measurement by ultrasound adds to the value of the
study.
23
Dept of Urology, GRH and KMC, Chennai.
24. Normal voiding includes
a detrusor muscle contraction,
coordinated bladder outlet relaxation,
low voiding pressure, and
a smooth, arc-shaped flow curve ( Schafer et al,
2002 ).
The flow pattern-the shape of the flow tracing,
sometimes be used to make a presumptive
diagnosis.
24
Dept of Urology, GRH and KMC, Chennai.
25. The normal flow
pattern is a
continuous, bell-
shaped, smooth curve
with a rapidly
increasing flow rate
25
Dept of Urology, GRH and KMC, Chennai.
26. The typical obstructed flow pattern has a plateau-
shaped curve with a prolonged flow time,
sustained low flow rate, and increased time to
Qmax.
An intermittent flow pattern is one that has one
or several episodes of flow increasing or
decreasing (or ceasing completely) and is
commonly secondary to abdominal straining or
external sphincter spasm (e.g., detrusor-sphincter
dyssynergia).
26
Dept of Urology, GRH and KMC, Chennai.
27. Data from the uroflow curve include
maximum flow rate,
total voided volume,
average flow rate, and
the postvoid residual.
The curve shape and Qmax is volume dependent, only
voided volumes of at least 150 mL should be
interpreted .
The maximum flow rate should always be
documented together with the total voided volume
and postvoid residual volume.
27
Dept of Urology, GRH and KMC, Chennai.
28. Uroflow in Men.
Normal uroflow parameters in young men are
well established.
Qmax greater than 15 to 20 mL/sec as normal and
less than 10 mL/sec abnormal.
Decline with age by 1 to 2 mL/sec per 5 years.
A maximum flow of 5.5 mL/sec at 80 years
28
Dept of Urology, GRH and KMC, Chennai.
29. Uroflow in Women.
Women have
a very short urethra,
minimal outlet resistance, and
no prostate,
only factors influencing female uroflow are
the strength of the detrusor muscle and
the urethral resistance and
the degree of relaxation of the sphincter mechanism.
In the normal woman Qmax can be greater than 30 mL/sec,
the flow curve is bell shaped as in men, and
the flow time is shorter
Maximum flow in women does not seem to be dependent
upon age.
29
Dept of Urology, GRH and KMC, Chennai.
30. The Cystometrogram
Cystometry –
The urodynamic investigation of the filling
component of bladder function.
30
Dept of Urology, GRH and KMC, Chennai.
31. The Procedure
Measurement of Intravesical and Abdominal
Pressure.
Zero pressure is the surrounding atmospheric
pressure.
the reference point is the superior edge of the pubic
symphysis
All systems must be zeroed to atmospheric pressure,
and it is crucial that there are no air bubbles in any of
the transducers or tubing as these may cause pressure
dampening or dissipation.
31
Dept of Urology, GRH and KMC, Chennai.
32. Fill Medium
A physiologic liquid medium is preferable.
Fluid cystometry uses more physiologic media such as
sterile water, normal saline, or contrast material.
These are not compressible and allow better
assessment of voiding dynamics.
Liquids allow easier detection of incontinence and are
more physiologic.
Other advantages
the ability to determine fluid loss and leak pressures
and
to serve as a medium for fluoroscopy.
32
Dept of Urology, GRH and KMC, Chennai.
33. The physical characteristics of the infused liquid
may affect bladder behavior and urodynamic
measurements. Acidic and alkaline solutions may
increase or decrease overactivity in otherwise
normal bladders.
Temperature is also important. eg. Iced water may
provoke overactivity,
33
Dept of Urology, GRH and KMC, Chennai.
34. FILL RATE
Slow (“physiologic”) fill—less than 10 mL/min
Medium fill—10 to 100 mL/min
Rapid fill—more than 100 mL/min
Filling is most often performed at a medium fill
rate with the slow rates reserved for second fills in
patients who demonstrate significant detrusor
overactivity at a faster fill rate.
Provocative filling using the faster rates may be
used to expose bladder overactivity in patients
with a complaint of urgency.
34
Dept of Urology, GRH and KMC, Chennai.
35. Prior to filling, we prefer to conduct a noninvasive
uroflow test as described earlier.
The patient is then catheterized for a postvoid
residual at the time of cystometry catheter
placement.
During cystometry, periodic coughing should be
elicited to ensure accurate pressure recording in
all channels being monitored (Pdet as derived
from Pves and Pabd).
35
Dept of Urology, GRH and KMC, Chennai.
36. A few common errors that result in inability to
obtain a correct zero include
pressure line displacement,
kinking of the tubing,
compression of the lumen of the tubing against
the bladder or rectal wall, and
the presence of air bubbles.
36
Dept of Urology, GRH and KMC, Chennai.
37. Filling cystometry
During the course of cystometry,
Four bladder characteristics;
capacity, sensation, compliance, and the
occurrence of involuntary contractions.
37
Dept of Urology, GRH and KMC, Chennai.
38. The typical cystometrogram
(CMG)
(I) The immediate rise to
resting bladder pressure -the
response of the viscoelastic
properties to the stretch of
filling.
(II) The tonus limb-the
viscoelastic properties of the
bladder wall.
(III) The point at which bladder
wall structures have achieved
maximal elongation and a
pressure rise is caused by
additional filling (i.e., exceeding
the limit of compliance).
(IV) The voiding phase
consisting of a voluntary
bladder contraction
38
Dept of Urology, GRH and KMC, Chennai.
39. The CMG in two components:
the response to filling
when capacity has been achieved,
the period of storage testing when there is no further
fill
patient stresses the full system with provocative
maneuvers such as
cough,
Valsalva maneuver, and
other provocative activities.
supraphysiologic filling rates
39
Dept of Urology, GRH and KMC, Chennai.
40. Capacity
Maximum cystometric capacity
bladder volume at the end of the filling CMG when
patients have a strong desire to void, feel they can no longer
delay micturition, and are given permission to void . This
volume includes 1.the amount voided and 2.the residual
urine left after the void (postvoid residual).
The functional bladder capacity is the largest volume voided
as determined by a voiding diary.
The cystometric capacity is usually slightly greater than
functional bladder capacity
The maximal anesthetic capacity is the volume of the
bladder after filling under anesthesia (general, spinal,
epidural) and is not routinely measured.
40
Dept of Urology, GRH and KMC, Chennai.
41. Sensation
Bladder sensation is evaluated by questioning the
patient about the feeling of the degree of bladder
fullness and is the point at which cooperation
between the patient and examiner becomes very
important.
Normal bladder sensation -
the first sensation of bladder filling,
the first desire to void, and
a strong desire to void .
Urgency,
pain, and
multiple other sensations should be documented
during filling as well .
41
Dept of Urology, GRH and KMC, Chennai.
42. Compliance
Bladder compliance is the relationship between
change in volume and change in pressure.
It is generally calculated between two points:
the Pdet with the bladder empty at the start of
filling and
the Pdet at either the maximal cystometric
capacity or the start of a detrusor contraction.
Normal bladder compliance should be less than
12.5 mL/cm H2O .
42
Dept of Urology, GRH and KMC, Chennai.
44. Storage
Normally, bladder filling
occurs with little or no
change in pressure, and
a “stable” bladder is a
reflection of the
integrity of the central
nervous system control
over bladder function.
There should be no
involuntary contractions
during filling
cystometry .
44
Dept of Urology, GRH and KMC, Chennai.
46. Cystometry summary
the normal bladder capacity is in the range of 300
to 500 mL;
the bladder should have a constant, low pressure
that usually does not reach more than 6 to 10 cm
H2O above baseline at the end of filling (end-
filling pressure); and
there should be no involuntary contractions.
46
Dept of Urology, GRH and KMC, Chennai.
47. Pitfalls in Cystometry
i. pressure measurement artifacts (the presence of air bubbles,
kinked tubing, incorrect placement, migration of the pressure
catheters) and
ii. infusion rate artifacts (especially in neurogenic bladder) and
iii. patient-related issues, including lack of cooperation, outlet
incompetence, and vesicoureteral reflux.
iv. If bladder filling is too rapid,
v. If the bladder outlet is incompetent, urine may leak around the
filling catheter and a low bladder compliance may not be
diagnosed because the bladder is never adequately filled (e.g.,
spinal dysraphism, severe intrinsic sphincter deficiency [ISD] in
an older woman).
47
Dept of Urology, GRH and KMC, Chennai.
48. Special Testing
Bethanechol supersensitivity test
The bethanechol supersensitivity test was described by
Lapides and modified by Glahn (1970) .
This test involves standard fluid infusion cystometry at a
filling rate of 1 mL/sec until a bladder volume of 100 mL is
achieved.
Bladder pressures are recorded, and
this is repeated two to three times for an average value.
Bethanechol chloride (0.035 mg/kg) then is administered
subcutaneously.
Cystometry is repeated at 10, 20, and 30 minutes after
injection. 48
Dept of Urology, GRH and KMC, Chennai.
49. A neurologically intact bladder should have a
pressure increase of less than 15 cm H2O above the
control value
a “denervated” bladder shows a response greater
than 15 cm H2O.
A positive test suggests an interruption in the
afferent or efferent peripheral, or distal spinal
innervation, of the bladder.
49
Dept of Urology, GRH and KMC, Chennai.
50. Ice water test
The ice water test was first described by Bors and
Blinn as a way to differentiate “upper” from
“lower” motor neuron lesions .
It is based on the principle that mucosal
temperature receptors can elicit a spinal reflex
contraction of the detrusor, a reflex that is
normally inhibited by supraspinal centers.
50
Dept of Urology, GRH and KMC, Chennai.
51. An upper motor neuron lesion interrupts these
inhibitory pathways, resulting in manifestation of
the reflex
A lower motor neuron lesion does not.
A positive test should therefore theoretically
occur in patients with upper motor neuron
lesions, whereas those with lower motor neuron
lesions and neurologically normal patients
should have a negative test.
51
Dept of Urology, GRH and KMC, Chennai.
52. The original test involved rapidly injecting the
bladder with ice water;
if the ice water is expelled by the bladder within 1
minute, the test is positive.
The test is positive in approximately 97% of
patients with complete suprasacral lesions and in
91% of those with incomplete suprasacral lesions;
it is almost never positive in patients with lower
motor neuron lesions.
52
Dept of Urology, GRH and KMC, Chennai.
53. Pressure-Flow Studies
Pressure-flow studies (PFSs) measure the relationship between
pressure in the bladder and urine flow rate during bladder emptying .
Indications :
❖ to differentiate between patients with low flow because of
obstruction and those with poor bladder contractility.
❖identify patients with high-pressure obstruction and normal flow
rates .
❖Obstruction
❖1. structural caused by prostatic enlargement and stricture, 2.
functional, caused by proximal or distal sphincter dyssynergia.
❖PFSs alone cannot identify the location of the obstruction, but when
combined with fluoroscopic screening or a sphincter EMG study, the
site of obstruction may be determined.
53
Dept of Urology, GRH and KMC, Chennai.
54. PFSs are especially useful in the evaluation of men with LUTS
A low flow rate is not diagnostic of BOO because 25% to 30% of
patients with low flow rates have detrusor hypocontractility
A normal or high flow rate does not rule out obstruction because 7%
of symptomatic men with a Qmax greater than 15 mL/sec have
obstruction
PFSs should be performed when the information obtained will
influence major therapeutic decisions.
Older men with LUTS and any H/O neurologic disease such as CVA,
multiple sclerosis, or Parkinson's disease, which are known to affect
detrusor or sphincter function.
Younger men with LUTS benefit from PFSs to determine whether a
functional disorder (e.g., bladder neck dysfunction) is present.
PFSs are also helpful in men with BPH and Qmax over 10 mL/sec, a
group making up 30% to 40% of BPH patients.
54
Dept of Urology, GRH and KMC, Chennai.
55. The normal male generally voids with a Pdet of 40
to 60 cm H2O, and women typically void with
lower pressures .
Obstruction existed in a patient with a Pdet of 100
cm H2O at a Qmax of 10 mL/sec.
55
Dept of Urology, GRH and KMC, Chennai.
56. women with LUTS, depending on the definition,
obstruction was identified in 2.7% to 20% of cases
PFSs may be misleading in women with suspected
obstruction.
56
Dept of Urology, GRH and KMC, Chennai.
57. Female Bladder Outlet Obstruction
Female bladder outlet obstruction is being recognized
more frequently, but standardized urodynamic
criteria for its diagnosis have been lacking.
Blaivas and Groutz (2000) have developed a
nomogram for the obstructed woman.
urodynamic values of maximum flow (Qmax) and
detrusor pressure at maximum flow (Pdet.max),
this nomogram defines obstruction in women as four
types:
no obstruction,
mild obstruction,
moderate obstruction, and
severe obstruction.
57
Dept of Urology, GRH and KMC, Chennai.
58. Abrams-Griffiths Nomogram.
The Abrams-Griffiths (AG) nomogram was based
on “theoretical analysis and empirical
observation” in symptomatic men undergoing
PFSs .
Categorized as
Obstructed- > 40 cm H2O
Equivocal- 20-40 cm H2O
Unobstructed- < 20 cm H2O.
AG nomogram is calculated from the formula
AG number = PdetQmax - 2Qmax .
58
Dept of Urology, GRH and KMC, Chennai.
59. for determining urethral resistance is based on
consideration of the urethra as a distensible tube with a
flow-controlling zone, the proximal urethra.
It describes the relationship between pressure and flow
during the period of lowest urethral resistance and
reflects the passive anatomic factors responsible for the
outlet resistance or flow-controlling zone and minimizes
the effect of muscular activity, such as sphincter contraction.
Schafer's method
59
Dept of Urology, GRH and KMC, Chennai.
60. Group-Specific Urethral Resistance
Factor nomogram.
The URA was derived from the recognition of a
correlation between the minimal opening pressure
(Pmuo) and the curvature of the PURR, resulting in
the ability to use one parameter, the URA, to define
obstruction.
A nomogram was created with a series of parabolic
curves showing the average pressure-flow plots for
different values of Pmuo.
By plotting the PdetQmax*Qmax point from a
patient's PFSs onto the nomogram, a corresponding
URA number is obtained.
A URA greater than 29 cm H2O is considered to
represent obstruction.
60
Dept of Urology, GRH and KMC, Chennai.
61. The ICS Provisional Nomogram
It is very similar to the AG nomogram except that the
boundary between unobstructed and equivocal has
been moved to reduce the size of the equivocal region.
A continuous grading of obstruction is possible by
calculating the bladder outlet obstruction index
(BOOI), which is essentially the AG number, given by
the formula
BOOI = PdetQmax - 2(Qmax).
The patient is considered
obstructed if the BOOI is greater than 40,
unobstructed if the BOOI is less than 20, and
equivocal if the BOOI is between 20 and 40.
61
Dept of Urology, GRH and KMC, Chennai.
63. An index of bladder contractility (bladder
contractility index [BCI]) can be factored
PdetQmax + 5Qmax.
Using this formula for the BCI (i.e., BCI =
PdetQmax + 5Qmax),
BCI greater than 150 is strong,
BCI less than 100 is weak, and
BCI of 100 to 150 is normal
contractility .
63
Dept of Urology, GRH and KMC, Chennai.
64. If this is plotted graphically on a nomogram,
patients can be categorized into nine classes,
according to three obstruction and three
contractility categories
64
Dept of Urology, GRH and KMC, Chennai.
65. Videourodynamics
Def : The simultaneous display of bladder and
urethral pressures with fluoroscopic imaging of the
lower tract is videourodynamics.
It is the most sophisticated form of evaluation of
patients with complex urinary tract dysfunction.
This is desirable when simultaneous evaluation of
structure and function is necessary to make a
diagnosis .
Videourodynamics is useful to identify the specific
site of the obstruction as being at the bladder neck,
the prostatic urethra, or the distal sphincter
mechanism .
65
Dept of Urology, GRH and KMC, Chennai.
67. A videourodynamic evaluation is indicated when a
diagnosis cannot be made with certainty without
simultaneous evaluation of the structure and
function of the urinary tract ( McGuire et al, 1996a ).
Anatomic abnormalities that can also be identified or
evaluated with videourodynamics include cystocele,
diverticulum of the bladder or urethra, and
abnormalities of the prostatic and proximal urethra,
and it may also give information on the pelvic support
and pelvic organ prolapse.
Significant pelvic organ prolapse may cause changes
in the urodynamic parameters measured, and the
significance of this cause may go unrecognized unless
fluoroscopy is added.
67
Dept of Urology, GRH and KMC, Chennai.
68. Videourodynamic studies can be performed
fluoroscopic units,
a fluoroscopy table, and
a radiographic contrast agent as the filling medium.
A tilting fluoroscopy table is necessary as it allows supine
placement of catheters with easy conversion to a sitting or
standing position to conduct the study.
A commode seat attached to the table facilitates
fluoroscopic screening of voiding in the seated position,
which is ideal for women.
An alternative system, used currently by these authors, uses
a fluoroscopic C-arm and a purpose-made tilting chair
system . 68
Dept of Urology, GRH and KMC, Chennai.
69. The basic video and urodynamic setup that allows both
urodynamic and radiologic imaging data to be projected
simultaneously onto a television monitor for real-time
viewing and for digital storage for later review.
Fluoroscopy time is limited by screening only points of
interest (Valsalva and cough events during fill and sections
of the voiding study) and should be less than 1 minute.
Many manufacturers make urodynamic equipment
integrating the video and pressure flow data.
The most important feature is the capability to measure
urethral and bladder pressures while displaying them
simultaneously with the corresponding fluoroscopic
images ( McGuire et al, 1996a ).
69
Dept of Urology, GRH and KMC, Chennai.
70. Using this technique, the examiner is able to gain information on many
aspects of the bladder and bladder function.
Vesicoureteral reflux and the status of the bladder neck and sphincter may
be identified.
The anatomy of the bladder, including diverticula, shape, and bladder
neck, may be determined as well.
Also, it allows identification of dyssynergia of the proximal and distal
sphincter mechanisms in neurogenic patients.
70
Dept of Urology, GRH and KMC, Chennai.
71. Particular Uses for Videourodynamics
1. Evaluation of Incontinence.
Identify the presence and degree of urethral
hypermobility, bladder neck competence, and the
presence and grade of cystocele.
Video also improves the accuracy of a Valsalva
leak point pressure (VLPP) measurement, making
it is easier to observe the exact moment when
leakage of contrast agent
71
Dept of Urology, GRH and KMC, Chennai.
72. 2. Bladder neck dysfunction
incomplete opening of the bladder neck during
urination. This was first fully described by Turner-
Warwick in 1973, most common in young men who
complain of long-standing LUTS ( Webster et al, 1980 ).
Urodynamics alone can easily show evidence of bladder
outlet obstruction.
The diagnosis of this disorder must be made with real-
time, fluoroscopic imaging of the micturition event
showing detrusor contraction in the absence of bladder
neck relaxation.
72
Dept of Urology, GRH and KMC, Chennai.
73. 3.Neurogenic Bladder Dysfunction.
For neurogenic detrusor overactivity,
simultaneous video screening detects the
presence of leakage per urethra or vesicoureteral
reflux
Aids in the determination of diagnosing proximal
and distal sphincter dyssynergia.
73
Dept of Urology, GRH and KMC, Chennai.
74. Identification of Associated
Pathology.
Videourodynamics allows the identification and
characterization of a pathologic process that can
be associated with complex voiding dysfunction,
including reflux, diverticula, fistulas, and stones.
74
Dept of Urology, GRH and KMC, Chennai.
75. Multichannel Urodynamics
The use of multichannel urodynamics,
incorporating these components into one all-
inclusive study.
Multichannel urodynamics use simultaneous
recording of total bladder pressure (Pves) and
separate abdominal pressure (Pabd).
Detrusor pressure (Pdet) is the component of
intravesical pressure (Pves) created by both active
(bladder contractions) and passive (elasticity)
forces from the bladder wall .
75
Dept of Urology, GRH and KMC, Chennai.
76. The detrusor pressure (Pdet) is derived by
subtracting the Pabd from Pves.
Pabd is most often recorded by a catheter placed
in the rectum.
76
Dept of Urology, GRH and KMC, Chennai.
77. The pressure transducers for the bladder and rectal
catheters must be at the same reference level (at the
upper edge of the pubic symphysis), and
the rectal catheter should be zeroed to equal bladder
pressure (which is zeroed to atmospheric pressure) at
the start of the study.
The lines should be flushed and the adequacy of
pressure transmission checked by having the patient
cough to demonstrate a rise in rectal pressure (Pabd),
a rise in vesical pressure (Pves), and essentially no
change in the subtracted detrusor pressure (Pdet).
77
Dept of Urology, GRH and KMC, Chennai.
78. Leak Point Pressures
Two pressures obtained during urodynamics
measure different aspects of lower urinary tract
function, detrusor leak point pressure (DLPP)
and abdominal leak point pressure (ALPP).
DLLP is defined by the ICS as the lowest detrusor
pressure at which urine leakage occurs in the
absence of either a detrusor contraction or
increased abdominal pressure.
ALPP is the intravesical pressure at which urine
leakage occurs because of increased abdominal
pressure in the absence of a detrusor contraction.
78
Dept of Urology, GRH and KMC, Chennai.
79. Detrusor Leak Point Pressure
The DLPP was first introduced by McGuire
An important concept in urodynamics is the fact that
bladder outlet resistance is the main determinant of
detrusor pressure
If the outlet resistance is high, a higher bladder pressure is
needed to overcome this resistance and cause leakage.
This high pressure can be transmitted to the upper tracts,
causing reflux and hydronephrosis.
McGuire found that in myelodysplastic patients with an
elevated outlet resistance from a fixed external sphincter,
those with a DLPP greater than 40 cm H2O were at
significantly higher risk for upper tract deterioration
(hydronephrosis, reflux).
79
Dept of Urology, GRH and KMC, Chennai.
80. The DLPP is the Pdet required to induce leakage
but does not determine what is causing the
elevated DLPP.
The addition of fluoroscopy allows an accurate
method for determining the presence and
location of obstructive uropathy.
80
Dept of Urology, GRH and KMC, Chennai.
81. Technique for Measurement of
DLPP.
The test is performed during cystometry.
The urethral meatus is observed for leakage while
bladder pressure is measured.
When leakage of urine is noted, the Pdet at that
instant is recorded as the DLPP .
DLPP greater than 40 cm H2O, there was a
significantly greater risk of
upper tract deterioration.
81
Dept of Urology, GRH and KMC, Chennai.
82. Abdominal Leak Point Pressure
Abdominal pressure does not open a normally
positioned and closed urethral sphincter.
Leakage can be caused only by an increase in
abdominal pressure when the urethra is
abnormal.
This led to the development of the Valsalva or
abdominal leak point pressure (VLPP, ALPP)
( McGuire et al, 1993 ).
82
Dept of Urology, GRH and KMC, Chennai.
83. Testing for ALPP should be done during cystometry
after the bladder has been filled to at least 150 to 200
mL.
The patient is then asked to do a Valsalva maneuver
until he or she leaks .
The lowest pressure at which incontinence occurs is
the VLPP.
If no leak occurs at measured abdominal pressures of
100 to 140 cm H2O, the patient is asked to cough until
incontinence occurs.
If there is no leakage with Valsalva or cough at this
volume, the test is repeated with a volume of 300 mL,
then again at capacity.
83
Dept of Urology, GRH and KMC, Chennai.
85. When there is no leakage at high pressures (>150
cm H2O), the urethra is unlikely to be the cause of
the patient's incontinence.
85
Dept of Urology, GRH and KMC, Chennai.
86. The VLPP or ALPP is reproducible and correlates
well with the grade of symptoms, severity of
incontinence, pad usage, and incontinence
quantification.
A VLPP less than 60 cm H2O indicates the
presence of significant ISD;
a VLPP of 60 to 90 cm H2O is equivocal, suggesting
a combination of urethral hypermobility and
some component of ISD; and
pressures greater than 90 cm H2O suggest urethral
hypermobility and minimal ISD.
86
Dept of Urology, GRH and KMC, Chennai.
87. Urethral Pressure Studies
Two variations of this measurement are
commonly reported:
The static urethral pressure profile (UPP), with its
variants the stress UPP and pressure transmission
ratios, and
The micturitional UPP.
87
Dept of Urology, GRH and KMC, Chennai.
88. Static Urethral Pressure
Profilometry
The urethral pressure is defined by the ICS as the
fluid pressure needed to just open a closed
urethra
The UPP is a graph indicating changes in the
intraluminal pressure along the length of the
urethra.
88
Dept of Urology, GRH and KMC, Chennai.
89. The UPP is obtained by recording the intraluminal pressure
changes along the length of the urethra without voiding.
A small (6 to 10 Fr) fluid-filled catheter with circumferentially
positioned side holes is withdrawn from the urethra at a rate of
0.5 cm/sec using a mechanical puller (although withdrawing the
catheter slowly by hand may also be reliable) while the catheter is
perfused with liquid at 2 mL/min.
The recorded urethral pressure corresponds to the pressure
needed to keep the urethra open by lifting the wall off the
catheter holes ( Yalla et al, 1980 ; Steele et al, 1998 ).
Ideally, bladder pressure is also measured to nullify the effects of
an associated bladder contraction.
The study may be performed at rest (static UPP) or with
intermittent stress events superimposed (stress UPP).
89
Dept of Urology, GRH and KMC, Chennai.
90. Stress Urethral Pressure
Profilometry
This is a UPP performed while the patient performs
periodic stress maneuvers (cough) and while
intravesical pressure is also recorded.
Normally, in women the proximal urethra is
supported intra-abdominally and increases in intra-
abdominal pressure are transmitted to both bladder
and the proximal urethra.
If this is not observed on the stress UPP, the
implication is that the urethra has fallen outside the
intra-abdominal influence (urethral hypermobility)
or the urethra is too rigid or scarred to be influenced
by this extrinsic compression.
90
Dept of Urology, GRH and KMC, Chennai.
91. This study is used to identify the presence and
location of bladder outlet obstruction.
It is performed in a similar fashion to the static UPP
except that the patient voids as the catheter is
withdrawn.
This allows bladder pressure to be compared with
urethral pressure at points along the urethra.
During voiding, bladder pressure should be close to
urethral pressure (isobaric).
If obstruction exists in the urethra, the pressure distal
to the obstruction is low while the bladder pressure,
and the pressure proximal to the obstruction, is high.
Thus, if a significant drop is encountered on catheter
withdrawal, this corresponds to the site of the
obstruction.
Micturitional Urethral Pressure Profilometry
91
Dept of Urology, GRH and KMC, Chennai.
92. AMBULATORY URODYNAMICS
Ambulatory urodynamic monitoring (AUM) is the
functional testing of the lower urinary tract, utilizing
natural filling and reproducing the patient's everyday
activities
It is a well-established method for investigating lower
urinary tract function while freeing the patient to be
independent and to perform activities that provoke the
urinary symptoms in question.
Its greatest benefit seems to be in patients in whom
conventional urodynamics is unsuitable or unable to
reproduce the symptoms that are being investigated.
92
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93. Guidelines for the performance of AUM
by the ICS
First,
detailed instructions about recording of symptoms,
identification of catheter displacement, and
hardware failure should be given to the patient.
Before the ambulatory investigation,
patients receive an extensive information sheet describing
the test and
the necessary preparation.
They are also provided with a simple diary to record
events,
allowing correlation of the test outcome with symptoms.
The patient is advised to empty the bowel, and urine is
checked for infection.
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Dept of Urology, GRH and KMC, Chennai.
94. measure intravesical and abdominal pressures using
fluid-filled lines, microtip transducers allow greater
mobility.
Catheters are placed and secured firmly and the data
are transmitted to a portable recording device .
Flow measurements can be made using home
uroflowmetry techniques, and
incontinence can be measured using standard pads .
Initial checks on signal quality by testing of recorded
pressure by coughing and abdominal straining in the
supine, sitting, and erect positions.
Regular cough tests should be carried out by the
patient throughout the study to serve as a quality
check during interpretation.
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Dept of Urology, GRH and KMC, Chennai.
95. Dis advantages
lack of minute to minute control on validity of the
signals.
position and fixation of the catheters
dislodgement of the devices.
the diary and data points.
This heavy reliance on patients' compliance may
be a source of significant error
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Dept of Urology, GRH and KMC, Chennai.
96. Analyses of the AUM tracings are always performed
retrospectively, making them time consuming and labor
intensive.
This should be done by a well-trained specialist ( van Waalwijk
van Doorn et al, 2000 ).
The examiner must assess the quality of data recorded by
evaluating several points.
The trace must be carefully examined for activity, which should
have fine second-to-second variation;
the cough tests and other activities that cause abdominal
pressure changes must be regularly present; and
the subtraction must be adequate with minimal change in the
derived detrusor pressure with coughing.
The patient's diary is invaluable to improve the detailed analysis
of events occurring during AUM.
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Dept of Urology, GRH and KMC, Chennai.
97. Applications of Ambulatory
Urodynamic Monitoring
Several studies have shown AUM to be more
sensitive for detection of unstable detrusor
contractions, making it helpful when a CMG is
nondiagnostic .
Another use of AUM is in patients with borderline
findings of obstruction and nondiagnostic PFSs.
Studies in both men with chronic retention and
patients with neurogenic bladder have noted that
filling pressures with AUM tend to be significantly
lower than those with a conventional CMG
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Dept of Urology, GRH and KMC, Chennai.
98. URODYNAMIC ANALYSIS AND
INTERPRETATION
A good urodynamic study is one that is easy to
analyze and would allow any urodynamicist to
come to the same conclusions.
The importance of monitoring the study in real
time in order to obtain the highest quality data
cannot be overemphasized .
Analysis of ambulatory studies will remain
problematic, as it is less easy to conduct real-time
quality assessment.
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Dept of Urology, GRH and KMC, Chennai.
99. The ICS in 2002 also has clearly stated that
“the urodynamic test should be repeated if the
initial test suggests an abnormality, leaves the
cause of troublesome LUTS unresolved, or if there
are technical problems preventing proper analysis.
If a study is inconclusive, one should consider the
consequences of not establishing a clear finding.
For instance, if an invasive therapy such as surgery
is planned, the urodynamics should be repeated or
the surgery deferred.”
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Dept of Urology, GRH and KMC, Chennai.
100. KEY POINTS
The goal in performing urodynamics is to answer
specific questions related to the patient's storage and
voiding function.
The simplest and least invasive tests can be used
initially with progression to more sophisticated testing
when the clinical examination and more simple tests
cannot make an accurate diagnosis.
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Dept of Urology, GRH and KMC, Chennai.
101. A well-prepared and counseled patient can contribute
extensively to a good urodynamic study.
All urodynamic procedures should be performed with
a clear indication and a specific question that can be
answered by the study.
Many medications may affect urodynamic outcomes
and should be stopped with an adequate washout
period prior to the test.
The International Continence Society has also
developed minimum technical specifications for
equipment and conductance of urodynamics. 101
Dept of Urology, GRH and KMC, Chennai.
102. The standard catheter for routine urodynamics should
be a transurethral, double-lumen catheter.
Cystometry must reproduce the patient's normal
clinical status in order to diagnosis and guide therapy.
Patients' understanding and compliance in conducting
the study are absolutely necessary, and a standardized
method must be followed in order to optimize
results.
Cystometry should evaluate five aspects of bladder
function: sensation, capacity, compliance, stability,
and emptying.
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Dept of Urology, GRH and KMC, Chennai.
103. Videourodynamics are indicated when a diagnosis
cannot be made with certainty without simultaneous
evaluation of the structure and function of the urinary
tract because they give information on anatomic
abnormalities.
Detrusor pressure is the component of intravesical
pressure created by both active and passive forces from
the bladder wall and is derived by subtracting the Pves
from Pabd (Pdet = Pabd - Pves).
Any urodynamic test should be repeated if the initial
test suggests an abnormality or leaves the cause of
symptoms unresolved and when there are technical
problems preventing proper analysis.
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Dept of Urology, GRH and KMC, Chennai.
104. A VLPP of less than 60 cm H2O indicates the presence
of significant ISD;
a VLPP of 60 to 90 cm H2O is equivocal, suggesting a
combination of urethral hypermobility and some
component of ISD; and
pressures greater than 90 cm H2O suggest urethral
hypermobility and minimal ISD.
Several studies have shown AUM to be more sensitive
than a conventional cystometrogram for detection of
unstable detrusor contractions, making it helpful when a
CMG is nondiagnostic. 104
Dept of Urology, GRH and KMC, Chennai.