- Repetitive nerve stimulation (RNS) involves electrically stimulating a nerve multiple times to assess neuromuscular transmission. It evaluates the safety factor and response to exercise at the neuromuscular junction.
- Slow RNS (3Hz) depletes quanta/acetylcholine, which can cause a >10% decrement in the compound muscle action potential amplitude. Rapid RNS (20-50Hz) prevents depletion through calcium accumulation, potentially causing increment.
- RNS helps distinguish pre- from post-synaptic disorders based on changes with exercise, fatigue and rapid stimulation patterns. It is useful for diagnosing myasthenia gravis and other neuromuscular transmission disorders.
what is RNS and what the techniques to perform this test in the lab. Its significance in the evaluation and diagnosis of NMJ disorders like MG, LEMBS etc..
Basic MEP techniques and understanding for Intraoperative neuromonitoring of the motors tracts during Brain and Spinal surgeries to prevent postoperative complications.
This presentation describes the common conditions, anatomy and the ideal ways to do and perform nerve conduction studies in lower limbs. It is nicely depicted with self explanatory pictures.
what is RNS and what the techniques to perform this test in the lab. Its significance in the evaluation and diagnosis of NMJ disorders like MG, LEMBS etc..
Basic MEP techniques and understanding for Intraoperative neuromonitoring of the motors tracts during Brain and Spinal surgeries to prevent postoperative complications.
This presentation describes the common conditions, anatomy and the ideal ways to do and perform nerve conduction studies in lower limbs. It is nicely depicted with self explanatory pictures.
Late response are the most helpful findings in some of the diseases affecting the peripheral nerves, (e.g GBS, Radiculopathies, ). How to assess these responses while performing Nerve Conduction Studies, is the most technical and theoretical consideration.... Here we go with the same things in the stated slides
This presentation is an introduction to the principles of Nerve Conduction Study and is entirely sourced from the book by David C Preston and Barbara E Shapiro: Electromyography and Neuromuscular disorders, 3rd Edition
This presentation discusses the basic principles governing EEG Rhythm Generation, and discusses the various circuits that generate and maintain cerebral oscillations.
Late response are the most helpful findings in some of the diseases affecting the peripheral nerves, (e.g GBS, Radiculopathies, ). How to assess these responses while performing Nerve Conduction Studies, is the most technical and theoretical consideration.... Here we go with the same things in the stated slides
This presentation is an introduction to the principles of Nerve Conduction Study and is entirely sourced from the book by David C Preston and Barbara E Shapiro: Electromyography and Neuromuscular disorders, 3rd Edition
This presentation discusses the basic principles governing EEG Rhythm Generation, and discusses the various circuits that generate and maintain cerebral oscillations.
Pharmacology Lecture Slides on Autonomic Nervous System Introduction by Sanjaya Mani Dixit Assistant Professor of Pharmacology at Kathmandu Medical College
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Best Ayurvedic medicine for Gas and IndigestionSwastikAyurveda
Here is the updated list of Top Best Ayurvedic medicine for Gas and Indigestion and those are Gas-O-Go Syp for Dyspepsia | Lavizyme Syrup for Acidity | Yumzyme Hepatoprotective Capsules etc
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
263778731218 Abortion Clinic /Pills In Harare ,ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group of receptionists, nurses, and physicians have worked together as a teamof receptionists, nurses, and physicians have worked together as a team wwww.lisywomensclinic.co.za/
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
- 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
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
The Gram stain is a fundamental technique in microbiology used to classify bacteria based on their cell wall structure. It provides a quick and simple method to distinguish between Gram-positive and Gram-negative bacteria, which have different susceptibilities to antibiotics
2. • Physiology of Neuromuscular junction
• Procedure & technical aspects
• Interpretation
• Application in various conditions
3. ANATOMY AND PHYSIOLOGY OF
NEUROMUSCULAR JUNCTION
The NMJ essentially forms an
electrical-chemical- electrical link between the nerve and
muscle.
The chemical neurotransmitter at the NMJ is Acetylcholine
(ACH).
ACH molecules are packaged as vesicles in the presynaptic
terminal in discrete units known as Quanta (Bags of
neurotransmitter (ACH).)
4. definitions
• Quantum. A quantum is the amount of Ach
packaged in a single vesicle.
• Each quantum (vesicle) 1 mV change of
postsynaptic membrane potential.
• The number of quanta released after a nerve
action potential depends on the number of
quanta in the immediately available (primary)
store and calcium stores
• Normally 50-300(60) vesicles
5. The quanta are located in three separate
stores:
Primary or immediately available store
1000 quanta- beneath presynaptic nerve terminal
membrane.
Secondary or mobilization store
10,000 quanta- supplies the primary stores after
few seconds.
Tertiary or reserve store.
More than 10,000 quanta –in the axon and cell
body
6. Calcium and quanta dynamics
• calcium :diffuses slowly out of the presynaptic
terminal in 100–200 msec.
• Ach stores: immediately available (primary)
store and secondary (or mobilization) store
• rapid RNS (more than every 100 msec, or
stimulation rate >10 Hz), calcium influx is
greatly enhanced and the probability of
release of Ach quanta increases.
7. PHYSIOLOGY
• When an nerve action potential invades and depolarizes the
presynaptic junction, voltage dependent calcium channels are
activated, allowing an influx of calcium.
• Results in release of ACH from the presynaptic terminals
• The greater the calcium inside the greater the more quanta (ACH) are
released.
• ACH then diffuses across the synaptic cleft and binds to ACH
receptors (ACHRs) on the post synaptic membrane
• In the post synaptic membrane – numerous junction are found with
ACH dependent gated channels and receptors.
• Thus the binding of ACH to ACHRs clustered opens ion channels…
resulting in a local depolarization, the End Plate Potential (EPP).
• The size of EPP depends on the amount of ACH that binds to the
ACHRs.
11. definitions
• End plate potential -EPP is the potential
generated at the postsynaptic membrane
following a nerve action potential and
neuromuscular transmission.
• 60 mV change in the amplitude of the
membrane potential.
• Safety factor: The safety factor of
neuromuscular transmission is simply defined
as the difference between the EPP and the
threshold potential for initiating an action
potential.
12. RNS EFFECT
During repetitive nerve stimulation in normal
subjects, ACH quanta are progressively
depleted from the primary store and fewer
quanta are released with each stimulation.
The corresponding EPP falls in amplitude but
b/c of normal safety factor it remains above
the threshold to ensure generation of a muscle
action potential with each stimulation.
After few seconds(1-2sec) the secondary store
begins to replace the depleted quanta with a
subsequent rise in the EPP.
13. PHYSIOLOGY OF RAPID RNS
In rapid RNS (10-50 Hz), depletion of quanta from the presynaptic
terminals is counterbalanced not only by the mobilization or
secondary stores but also by accumulation of calcium.
Normally it takes 100 msec for ca2+ to diffuse back out of the
presynaptic terminals. If RNS is rapid enough so that new ca2+
influx occurs before previously infused ca2+ had diffused back
out, ca2+ continues to accumulate in the presynaptic terminals,
causing an increased release of quanta.
This combination of factors usually leads to an increased number of
quanta released and a corresponding higher EPP. However, the result
in normal subject is same i.e the generation of a muscle action
potential.
14. SLOW AND RAPID RNS
• The effect of rapid and slow RNS is the same to generate the Muscle
action potential in normal subjects.
In Pathological Conditions:
• Where the safety factors is reduced i.e. the baseline EPP is reduced
but still above the threshold the slow RNS will cause depletion of
quanta and may drop the EPP below threshold, resulting on the
absence of muscle action potential.
• Where the baseline EPP is below the threshold and a muscle action
potential is not generated, rapid RNS may increase the number of
quanta released, resulting in a larger EPP so that threshold is reached.
15. Potentiation
• voluntary activation or high frequency
stimulation
• CMAP amp increases
• Facilitation:-recruitment
• Pseudo facilitation:-synchronisation of muscle
activity
18. Repetitive nerve stimulation
( RNS)
• Jolly in 1895 first described progressive
reduction in visible muscle contraction in MG
(Myaesthenic reaction)
• Harvey and Masland(1941) reported electrical
decremental muscle response on repetitive
motor nerve stimulation.
• Ekstedt in 1964 described SFEMG
19. RNS- technique
• RNS is technically demanding procedure.
• Poor electrode placement, sub maximal
stimulation, movement artifacts, causes false
positive results
• Minimise artifacts
• Immobilisation
20. RNS-technique
• RNS is performed on selected motor nerves
with recording by surface electrodes.
• G1-motor point,G2-tendon
• Supramaximal stimulus
• Initial sharp negative deflection
21. Muscle selection
• Clinically weak muscles should be selected.
• Usually facial and proximal limb muscles shows
greater abnormality than distal muscles.
• Nerves involved in other diseases should be
avoided.
• Cholinesterase inhibitors should be stopped 12-
24 hrs before.
22. RNS PROTOCOL
• Slow Repetitive Nerve Stimulation (RNS) is performed in following sequence
• One Distal and one proximal motor nerves(preferable most involved muscles)
• One Sensory nerve
• RNS protocol
– Resting or base line trace 6 trains at-least (10 trains are preferred)
– Post 10 second exercise 6 trains
– Post 1 minute exercise 6 trains
– 1 minute post 1 minute exercise 6 trains
– 2 minute post 1 minute exercise 6 trains
– 3 minute post 1 minute exercise 6 trains
– 4 minute post 1 minute exercise (optional) 6 trains
– If decrement is noted, perform Post 10 second exercise stimulation 6 trains, for facilitation
• In Myasthenia gravis persistent Decremental Response > 10% is abnormal. The maximum
Decremental response is noted 2 or 3 minute post 1 minute exercise.
• If patient is unable to perform exercise, fast RNS at 30Hz or 50Hz may be used.
23. Protocol For Evaluating Disorder Of NMJ
• Warm the extremity (33 degree centigrade)
• Immobilize the muscle as best as possible
• Perform RNS at rest. After making sure that
the stimulus is supramaximal, perform at 3
Hz RNS, normally there is a less than 10%
decrement b/w the first and the fourth
response.
24. Cont. Protocol
If more than 10% decrement occurs and is
consistently reproducible:
Have patient perform maximal voluntary exercise &
immediately repeat 3 Hz RNS post exercise.
If a less than 10% decrement or no decrement:
Have patient perform maximal voluntary exercise for
1 min & perform 3 Hz RNS immediately and at
1,2,3 and 4 mins.
If a significant decrement occurs after 1 min exercise
(post exercise Exhaustion), have patient perform
maximal voluntary exercise again for 10 sec and
immediately repeat RNS at 3 Hz to demonstrate
repair of the decrement.
25. Cont. Protocol
Perform RNS on one distal and one proximal
muscles especially the weak muscles.
If no decrement is found with a proximal limb
muscle, a facial muscle can be tested.
If the compound muscle action potential is low at
baseline, have patient perform 10 sec exercise,
then stimulate the nerve supramaximally
immediately post exercise, looking for an
abnormal increment response ( greater than 140%
of the baseline). If the patient cannot exercises,
rapid RNS should be used.
26.
27.
28. Slow RNS
• supra maximal CMAP
• 3–5 stimuli to a mixed or motor nerve at a rate
of 2–3 Hz.
• slow enough to prevent calcium accumulation,
high enough to deplete the quanta
• maximal decrease in Ach release occur after the
first four stimuli
• reproducible decrement
• exercises for 10 seconds to demonstrate repair of
the decrement (‘‘post-exercise facilitation’’)
• If no decrement occurs -1 minute max voluntary
exercise –”post exercise exhaustion”
30. Rapid RNS
• optimal frequency is 20–50 Hz,for 2–10
seconds
• brief (10-second) period of maximal voluntary
isometric exercise has the same effect as rapid
RNS
• Depletion of quanta vs calcium accumulation
• Incremental response in LEMS
33. RNS in pre and post synaptic disorders
ParameterParameter Pre-synapticPre-synaptic Post-synapticPost-synaptic
CMAP amplitudeCMAP amplitude SmallSmall NormalNormal
Low rate RNSLow rate RNS
RestingResting
Post exercisePost exercise
facilitationfacilitation
Post exercisePost exercise
exhaustionexhaustion
DecrementDecrement
PresentPresent
AbsentAbsent
DecrementDecrement
PresentPresent
PresentPresent
High rate RNSHigh rate RNS IncrementIncrement Decrement orDecrement or
normalnormal
34. Electrophysiological investigation
• Nerve conduction studies-usually normal
(low CMAP in LEMS)
• Concentric needle EMG-usually normal
• Repetitive nerve stimulation
• Single fiber EMG
35. RNS in MYASTHENIA GRAVIS
• Most commonly used test, easy.
• RNS is relatively insensitive,10-50% in ocular
myastenia,75% in generalised MG
• RNS is relatively specific(90%)
• SFEMG is Most sensitive.(90% in ocular,95% in
MG)
• Normal baseline CMAP
• Greater than 10% decremental response at rest
and post exercise
• No role for high frequency stimulation
39. Congenital Myasthenic Syndromes
• Newborns of non-Myasthenic mothers.
• No Ach R antibodies.
• Respiratory distress, feeding difficulty, Ptosis
are common.
• Decremental response on 2 Hz RNS, abnormal
SF-EMG.
• End plate acetyl cholinesterase deficiency and
slow channel syndrome , a repetitive CMAP is
elicited by a single supramaximal stimulus.
43. LEMS
• Distal muscles RNS preferred
• 3 pattern recognized
• Low normal CMAP amplitude, decremental
response at low rate RNS, normal at high rate.
• Low CMAP amplitude, decremental response
at low rate, and incremental response at high
rate RNS (>100%)—classical triad.
• Low CMAP amplitude, decremental low rate
RNS, initial decrement at high rate RNS.
44. Incrementing response
after brief exercise (10-15
sec) in LEMS. Increment
is 10-fold, with CMAP of
3.2 mV.
CP CMAP amplitude is
0.35 mV (normal >1
mV).
47. Botulism
• Defective release of Ach from nerve terminals.
• It cleaves synaptic vesicle protein.
• Extra ocular and bulbar weakness limb and
respiratory weakness.
• Blurred vision, dilated pupil, constipation,
urinary retention.
• Electro physiologically resemble LEMS
48. Botulism
• Reduced CMAP in at least two muscles
• At least 20 percent CMAP amplitude
facilitation on tetanic stimulation
• Persistance of facilitation atleast 2 minutes
after activation
• No postactivation exhaustion