1) The rectum is the lower dilated part of the large gut located in the pelvic cavity. It is 12 cm long and has both anterior-posterior and lateral curvatures.
2) The anal canal is the terminal part of the alimentary tube located below the rectum. It is lined by different types of epithelium in its upper, intermediate, and lower areas.
3) Both structures have layers including mucosa, submucosa, muscularis, and serosa. They receive blood supply from superior, middle, and inferior rectal arteries and drain into portal and systemic veins.
anatomy of duodenum, location or position of duodenum, parts of duodenum, relations of each parts of duodenum, ligaments of treitz, visceral and peritoneal relation of duodenum, blood supply of duodenum, innervation of duodenum, clinical aspects of duodenum, duodenal ulcer, diverticulum, deodinitis, duodenal obstruction
Anatomy of urinary bladder. surfaces, border of urinary bladder its relation , ligament support, peritoneal relation in male and females, pouches, blood supply of bladder, nerve supply of bladder, true and false ligament of urinary bladder,
This article covers the anatomy of the inguinal canal, including contents, borders,the spermatic cord,the ilioinguinal nerve and related clinical aspects, such as hernias
A brief slide presentation on inguinal region including both inguinal canal and ligament and applied anatomy. Just read the theory properly and follow the diagrams.
neuronal organelles
the neuron contains all the regular organelles of the eukaryotic cells. however, rough endoplasmic
reticulum, free ribosomes and polyribosomes of the neurons are collectively referred to as the nissl
(chromophil) bodies (granules).
these organelles are responsible for the intense basophilia of the neuronal perikaryon and are absent in the
axon hillock and in the axon (see diagram 3.).
neurofibrils, neurofilaments, microtubules and microfilaments are widely distributed in the cell body, axon
and dendrites.
golgi complex and lysosomes are restricted to the cell body while mitochondria are widely distributed in all
parts of the neuron but are particularly abundant at the axonal terminals.
inclusion bodies:
the neuron also contains inclusion bodies, which have variable distribution in the nervous system, e.g.:
melanin pigments (neuromelanin) are found in the substantia nigra of the midbrain and locus coeruleus of
the pons in the brainstem
lipofuscin (lipochrome) pigments are found in the spinal cord, medulla oblongata, sensory and
sympathetic ganglia. they are stored in granules derived from lysosomes. lipofuscin appears from the age
of 8 and increases with age. they may appear in other nerve cells but never found in the purkinje cells of
the cerebellum.
other inclusion bodies include:
zinc metal in the hippocampus of the brain
iron metal in the occolomotor nucleus of the midbrain
calcium and magnesium salts (brain sand) in the pineal gland.
synaptic vesicles are membrane-bound sacs of neurotransmitter located at the boutons terminaux of axons.
the axon :( see diagram 3a and 3b)
the characteristic features of the axon are:
a.it arises from the region of the cell body called the axon hillock
b.it is often longer than the dendrites but of uniform diameter.
c.a typical neuron possesses only one axon.
d.its plasmalemma is called the axolemma and its cytoplasm the axoplasm.
e.it contains all neuronal organelles except nissl bodies and golgi complex.
f.may have collateral branches.
g.may be covered by myelin sheath for insulation and rapid conduction of impulses.
h.conducts impulses away from the cell body.
i.its terminal branches are called telodendria, which terminate in dilated terminals (boutons
terminaux) that are involved in formation of contact points called synapses.
j.the initial segment is often involved in inhibitory axo-axonal synapses.
the dendrite (see diagram 3.)
the characteristic features of the dendrite are:
a.it is often shorter than the axon and tapers from the cell body hence the diameter is not
uniform.
b.it has numerous branches.
Here is the powerpoint on relevent anatomy of multiple differentials for Inguinoscrtal swelling special for surgical diagnosis with very reliable References.
anatomy of duodenum, location or position of duodenum, parts of duodenum, relations of each parts of duodenum, ligaments of treitz, visceral and peritoneal relation of duodenum, blood supply of duodenum, innervation of duodenum, clinical aspects of duodenum, duodenal ulcer, diverticulum, deodinitis, duodenal obstruction
Anatomy of urinary bladder. surfaces, border of urinary bladder its relation , ligament support, peritoneal relation in male and females, pouches, blood supply of bladder, nerve supply of bladder, true and false ligament of urinary bladder,
This article covers the anatomy of the inguinal canal, including contents, borders,the spermatic cord,the ilioinguinal nerve and related clinical aspects, such as hernias
A brief slide presentation on inguinal region including both inguinal canal and ligament and applied anatomy. Just read the theory properly and follow the diagrams.
neuronal organelles
the neuron contains all the regular organelles of the eukaryotic cells. however, rough endoplasmic
reticulum, free ribosomes and polyribosomes of the neurons are collectively referred to as the nissl
(chromophil) bodies (granules).
these organelles are responsible for the intense basophilia of the neuronal perikaryon and are absent in the
axon hillock and in the axon (see diagram 3.).
neurofibrils, neurofilaments, microtubules and microfilaments are widely distributed in the cell body, axon
and dendrites.
golgi complex and lysosomes are restricted to the cell body while mitochondria are widely distributed in all
parts of the neuron but are particularly abundant at the axonal terminals.
inclusion bodies:
the neuron also contains inclusion bodies, which have variable distribution in the nervous system, e.g.:
melanin pigments (neuromelanin) are found in the substantia nigra of the midbrain and locus coeruleus of
the pons in the brainstem
lipofuscin (lipochrome) pigments are found in the spinal cord, medulla oblongata, sensory and
sympathetic ganglia. they are stored in granules derived from lysosomes. lipofuscin appears from the age
of 8 and increases with age. they may appear in other nerve cells but never found in the purkinje cells of
the cerebellum.
other inclusion bodies include:
zinc metal in the hippocampus of the brain
iron metal in the occolomotor nucleus of the midbrain
calcium and magnesium salts (brain sand) in the pineal gland.
synaptic vesicles are membrane-bound sacs of neurotransmitter located at the boutons terminaux of axons.
the axon :( see diagram 3a and 3b)
the characteristic features of the axon are:
a.it arises from the region of the cell body called the axon hillock
b.it is often longer than the dendrites but of uniform diameter.
c.a typical neuron possesses only one axon.
d.its plasmalemma is called the axolemma and its cytoplasm the axoplasm.
e.it contains all neuronal organelles except nissl bodies and golgi complex.
f.may have collateral branches.
g.may be covered by myelin sheath for insulation and rapid conduction of impulses.
h.conducts impulses away from the cell body.
i.its terminal branches are called telodendria, which terminate in dilated terminals (boutons
terminaux) that are involved in formation of contact points called synapses.
j.the initial segment is often involved in inhibitory axo-axonal synapses.
the dendrite (see diagram 3.)
the characteristic features of the dendrite are:
a.it is often shorter than the axon and tapers from the cell body hence the diameter is not
uniform.
b.it has numerous branches.
Here is the powerpoint on relevent anatomy of multiple differentials for Inguinoscrtal swelling special for surgical diagnosis with very reliable References.
This presentation provides an overview of the gross anatomy of the inguinal canal, a passage in the lower abdomen that allows the spermatic cord (in males) or round ligament (in females) to pass from the abdomen to the scrotum (in males) or labia majora (in females). The presentation includes images and diagrams to help explain the anatomy of the inguinal canal
urinary system includes kidney, ureter, urinary bladder and urethra.
kidney is retroperitoneal with 4 layers of coverings. 2 boarders, 2 surfaces and poles. hilum contains neuro vascular structures and ureter. ureter lies posteriorly.
ureter is muscular tube parts are pelvis, abdominal and pelvic part
Rectum means straight as if ruled. This is a misnorma,for it is curved in conformity with the hollow of the sacrum.
Rectum is continuous with the sigmoid colon and there is no change of structure at the junction. The distinction is a matter of peritoneal attachment; where there is a mesocolon, the gut is called sigmoid colon and where there is no mesentery, it is called rectum . Where the muscle coats are replaced by sphincters it becomes the anal canal.
The rectum begins in the hollow of the sacrum at the level of its 3rd. Piece and it curves forwards over coccyx and ano-coccygeal raphe.
It is 15 cm long.
The 3 tinea of the sigmoid colon come together over the rectum invest it in a complete outer layer of the longitudinal muscle.
The upper and lower ends of the rectum lie in the midline but the ampulla is convex to the left.
Rectal valves of Houston,2 on the left and one on the Right are produced by circular muscles of the gut.
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
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
Factory Supply Best Quality Pmk Oil CAS 28578–16–7 PMK Powder in Stockrebeccabio
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micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
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
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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
1. Rectum & Anal Canal
Dr. Mushfiqul Hoque
Lecturer
Dhaka National Medical College
2.
3. Gross Anatomy
• Means straight tube
• But it is not straight in humans
• Still it is called rectum because it is straight in all other mammals
• Hence rectum is a misnomer in case of human
4.
5. Gross Anatomy
• Rectum is the lower dilated part of the large gut
• Contained in the pelvic cavity
• Although it is part of large gut but it is devoid of taenia coli,
sacculations and appendices epiploicae and mesentery
6. Course
• Begins: in front of third sacral
vertebra where sigmoid
mesocolon ends
• Ends: at ano-rectal junction
which is situated where rectal
ampula suddenly becomes
narrow, corresponds with the
apex of the prostate in male
7. Measurements
• Length: 12cm (5 inches)
• Breadth: upper part – 4cm
• Lower part forms a dilatation known as Ampulla
8. Curvatures or flexures
• Anterior-posterior curvatures:
1. Sacral curve: convex backwards
towards the hollow of the sacrum
2. Perineal curve: convex forwards at
the ano-rectal junction and is
maintained by the pubo-rectal sling
of levator ani.
9. Curvatures or flexures
• Lateral curvatures:
1. Upper curve: convex to the
right at the junction of third
and fourth sacral vertebra
2. Middle curve: most prominent
and convex to the left side at
the sacro-coccygeal junction
3. Lower curve: convex to the
right at the tip of the coccyx
10. Importance of lateral curves
• Lateral curves are rudimentary
sacculations affecting the sides of the
rectum only
• Along the concavities of the curves
horizontal rectal valves project into the
interior of the rectum and support the
weight of the faeces
11. Peritoneal relations of the rectum
• Posterior surface of the rectum is
entirely non peritoneal
• Anterior surface is covered in
peritoneum in upper two third of
the rectum
• In upper one third the peritoneum
covers the front and sides of the
rectum
• In the middle one third it covers only
the front
12. Anterior Relations of the rectum in male
• Base of the urinary bladder, a pair of
seminal vesicles, ampulla of the vas
deferens and the posterior surface of
prostate
• The above mentioned structures are
separated from the rectum by recto-
vesical fascia of Denonvillier
13. Anterior Relations of the rectum in female
• Middle two-fourth of the posterior
vaginal wall
• It is separated from the rectal
ampulla by ill-defined recto-vaginal
fascia
14. Structure of rectum
From outside to inwards rectum
presents 4 layers:
1. Serous: derived from peritoneum
2. Muscular: longitudinal & circular
3. Submucous: loose areolar tissue &
plexuses of blood vessels,
lymphatic and nerves
4. Mucous: 3 layers:
a) Muscularis mucosa
b) Lamina propria
c) Surface epithelium: simple columnar
cells, numerous goblet cells, crypts of
lieberkuhn
15. Muscular layer
Longitudinal muscle layer:
• Thick in front and behind
• Anterior band is continuous above
with taenia libera and omentalis
• Posterior band is continuous above
with taenia mesocolica
16. Interior of rectum
2 types of mucous folds found in the
interior
• Temporary folds: longitudinal in
direction, usually in the lower part of
rectum, disappear when the organ is
distended
• Permanent mucous folds: also
known as Houston's valves
17. Permanent folds
Houston's valves:
• Horizontal in direction
• Semilunar in shape
• Along the concavities of the
lateral curves
• Formed by reduplication of
mucous membrane containing
submucous tissue and
thickening of circular muscle
of rectum
Four in number
First and third valve are constant
18. Permanent folds: 3rd valve
• Most important and constant
• Arises from anterior and right wall
of rectum
• Situated opposite to 5th sacral
vertebra and 5cm above the anus
• Part of rectum above this valve is
developed from pre-allantoic part
of hind gut
• Rectum below this valve is
developed from post-allantoic part
of cloaca
19. Importance of Houston's valves
• Support the weight of the faeces
• Prevents passage of instrument
from the anus unless carefully
passed
20. Arterial supply of rectum
Supplied by five rectal arteries:
• Unpaired superior rectal artery
• Pair of middle rectal artery
• Pair of inferior rectal artery
In addition:
• Median sacral artery
• Inferior gluteal artery
• Internal pudendal artery
21. Arterial supply of rectum
1. Superior rectal artery: continuation
of inferior mesenteric artery
2. Middle rectal artery: branch of
anterior division of each internal
iliac artery
3. Inferior rectal artery: branch of
internal pudendal artery
22. Venous drainage of rectum
• Rectal veins are arranged in 2
plexuses of vein.
1. Internal venous plexus
2.External venous plexus
• Drainage:
1. 6 veins from the upper part of the
plexuses drain into trunk of superior
rectal vein which drains into inferior
mesenteric vein (portal vein)
2.Middle rectal vein from middle part
of the plexuses and drains into
internal iliac vein ( systemic)
3.Inferior rectal vein from the lower
part drains into internal pudendal
vein (systemic)
23. Importance of rectal veins
• Important site for communication
between portal and systemic veins
• Radicles of superior rectal veins
are devoid of valves and are
surrounded by loose areolar tissue.
In case of increased portal
pressure they are likely to be
distended
24. Lymphatics
• 2 plexuses: intramural and
extramural
• Intramural plexuses communicate
with the extramural plexus
• Extramural plexus drain into
1.From upper part: left common iliac
nodes
2.Middle part: internal iliac nodes
3.Lower part: internal iliac nodes
• From the anal canal below the anal
valves: superficial inguinal lymph
nodes
25. Nerve supply of the rectum
• Sympathetic: superior hypogastric
plexus (L1, L2)
• Parasympathetic: pelvic splanchnic
nerves (S1, S2, S3)
26. Supports of the rectum
• Pubo-rectal sling or levator ani
• Reflexion of pelvic fascia
• Fascial sheet of waldeyer
• Pelvi-rectal and ischio-rectal fat
27. Developmental anomalies of rectum
• Imperforate anus
• Congenital recto-vesical or
rectourethral fistula
• Congenital recto-vaginal fistula
• Ectopic anus
• Undivided cloaca
29. Gross anatomy
• Terminal part of alimentary tube
• Begins at ano-rectal junction
• Situation slightly below the tip of
the coccyx
• Length 3.8cm
30. Peculiarities of the anal canal
• Anterior wall is shorter than the
posterior wall
• It is surrounded by sphincter ani
muscles, the tone of which keeps
the canal closed except during
defaecation
31. Interior of the anal canal
• Pectinate line: it is the muco-
cutaneous junction in the anal
canal dividing anal canal into
upper and lower parts
• Hilton's line: it is the line which
divides between two colour
contrast, between bluish pink area
and black skin below
32. Interior of the anal canal
• Aanal canal is divided into upper.
Intermediate and lower by the
pectinate line and the Hilton's line
• Distended varicose veins in the
area above the pectinate line is
known as internal haemorrhoids
(piles) and those below the
pectinate line is called external
haemorrhoids (piles)
33. Interior of the anal canal
Upper area: limited below by the
pectinate line. Lined by simple
columnar or stratified columnar or
stratified squamous. This are presents
the following:
• Anal columns
• Anal valves
• Anal papillae
• Anal sinuses
• Anal glands
34. Interior of the anal canal
• Anal columns: also known as
columns of morgagni, these are
permanent mucous folds, 6-10 in
number, more prominent in children,
formed by reduplication of mucous
membrane containing radicles of
rectal vessels.
35. Interior of the anal canal
• Anal valve: crescentic mucous folds,
connecting the lower ends of the
anal columns, upper surface of the
valves are lined by simple columnar
epithelium and lower surface is lined
by stratified epithelium.
• Anal papillae: sometimes epithelial
processes project from the free
margins of the valves.
• Anal sinuses: recess above the valves
and in between the anal columns
36. Interior of the anal canal
• Intermediate area: in between
hilton's line and pectinate line, lined
by non-keratinized stratified
squamous epithelium
• Lower area: area below Hilton's line,
8mm in length lined by true skin
37. Importance of pectinate line
• Developmental: upper area is developed from endodermal cloaca and lower area
is developed from ectodermal proctodeum
• Upper area is supplied by superior rectal artery and lower area by inferior rectal
artery
• Upper area is drained into the portal system and lower area into systemic veins
• Lymphatic: upper area drains into internal iliac nodes and lower area into
superficial inguinal nodes
• Nerve supply: upper area supplied by autonomic nerves including sympathetic
(superior hypogastric plexus) and parasympathetic (pelvic splanchnic nerves).
Lower area is supplied by somatic nerves via inferior rectal nerves
38. Sphincters of the anal canal
• Internal anal sphincter or sphincter
ani internus
• External anal sphincter or sphincter
ani externus
39. Sphincters of the anal canal
Internal anal sphincter or sphincter ani
internus
• Involuntary sphincter
• Formed by thickening of the circular
muscles of the lower part of rectum
• Surrounds upper three-fourth of the
anal canal
• Nerve supply: sympathetic: superior
hypogastric plexus. Parasympathetic
by pelvic splanchnic nerves
40. Sphincters of the anal canal
External anal sphincter or sphincter
ani externus:
• Voluntary sphincter
• 3 parts: subcutaneous, superficial
and deep
• Subcutaneous part: flattened band
around the anus
• Superficial part: elliptical in shape,
arises from the tip of the coccyx
• Deep part: annular in shape,
surrounds ano-rectal junction, has
no bony attachment
41. Sphincters of the anal canal
Nerve supply of the External anal
sphincter
• Inferior rectal branch of pudendal
nerves
• Perineal branch of fourth sacral
nerve
