Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of...
Transcript of Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of...
![Page 1: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/1.jpg)
Ultrasound to Enhance NCS and EMG
Andrea J. Boon MDMayo Clinic, Rochester, MN
![Page 2: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/2.jpg)
Overview
• Background• Rationale for use of ultrasound
• Clinical applications• Localization for NCS• Localization for EMG
• Diagnostic nerve ultrasound• Diagnostic muscle ultrasound
![Page 3: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/3.jpg)
Why use US in the EMG lab?
• Electrodiagnosis provides pathophysiologic information
• Ultrasound provides anatomical and structural information
• Using the two tests together is often complementary
• Improving safety and accuracy• Increasing diagnostic yield
![Page 4: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/4.jpg)
NCS: Reasons to consider US
• Near nerve needle placement• Verify conduction block• Repetitive stimulation (femoral)• Record from small sensory nerves
• Direct visualization of needle• Enhance safety• Enhance accuracy (obesity)
• Observe the target muscle
![Page 5: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/5.jpg)
Near Nerve Needle Placement
![Page 6: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/6.jpg)
Ultrasound is Particularly Helpful for Challenging Cases
• Obesity• Altered anatomy• Anticoagulation• High risk structures in proximity• Unusual or less commonly studied
nerves
![Page 7: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/7.jpg)
Difficult Sensory NCS
• Lateral femoral cutaneous• Saphenous• Transposed ulnar nerve• Femoral
• Obesity, anticoagulation
![Page 8: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/8.jpg)
Lateral Femoral Cutaneous Nerve
![Page 9: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/9.jpg)
Results
• 50 patients, 21 – 82 years old• Mean BMI 27.7 (high 36.8)• No response using Shin’s technique
• 4 subjects• No response using US guided
technique: 3/50 normals• 1 patient with BMI > 35• Needle recording in 3 cases
![Page 10: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/10.jpg)
![Page 11: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/11.jpg)
![Page 12: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/12.jpg)
![Page 13: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/13.jpg)
Eliminate false negatives
![Page 14: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/14.jpg)
M mode• Visualization of the diaphragm
muscle with ultrasound improves diagnostic accuracy of phrenic nerve conduction studies.
• Johnson et al. Muscle & Nerve 2014 May;49(5):669-75. doi: 10.1002/mus.24059. 2014.
©2011 MFMER | slide-14
![Page 15: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/15.jpg)
Intraneural Ganglion – Fibular
![Page 16: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/16.jpg)
Muscle Imaging
• As a localization tool for EMG• Do we really need it??
• As a diagnostic tool
![Page 17: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/17.jpg)
Accuracy of Needle EMG• Cadaver studies
• High rate of inaccuracy in certain muscles even with experience 1• < 50% accuracy (18 muscles)
• Subscapularis accuracy 2• 3 methods: 0% to 78% accuracy
• Lumbar multifidi: 87% accuracy 3• Thoracic muscles: 69% accuracy 4
1Haig et al. 2003 2Choido et al. 2005 3Chinsethagij et al. 2003 4Choido et al. 2006
![Page 18: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/18.jpg)
27 gauge EMG needle
![Page 19: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/19.jpg)
Muscle US: As a localization tool
• If selective activation not possible• Severely weak• Spasticity
• Chemodenervation• Adjacent muscles activated with
same motion, different innervation• Fine wire placement
![Page 20: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/20.jpg)
Muscle US: As a Localization Tool
• Less experienced EMGer• Enhance accuracy• Improve anatomical knowledge
• Experienced EMGer• Small, deep or unfamiliar muscles• Anticoagulation: high risk muscles• High risk muscles• Altered anatomy, graft• Obesity
![Page 21: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/21.jpg)
Muscles where I might use US
• Chest wall muscles• Diaphragm• Popliteus• Gracilis transplant• FDP I/II vs. FDP III/IV• Iliopsoas, Posterior tibialis, FHL, FPL
![Page 22: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/22.jpg)
Unusual Muscles - Popliteus
![Page 23: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/23.jpg)
Supinator, with radial nerve
![Page 24: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/24.jpg)
Anticoagulation
• US: good tool for high risk muscles• Use Doppler to identify vessels• Can place needle under direct US
guidance• Iliopsoas, Posterior tibialis, FPL,
Paraspinals, Diaphragm• Post procedure monitoring
![Page 25: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/25.jpg)
Anticoagulation
• We studied bleeding risk post EMG• Risk of stopping A/C outweighs
risk of EMG• Helped change our practice
• Proceed with EMG if INR < 3.0• INR > 3.0, determined by the
individual staff• We now have literature to support
that practice
![Page 26: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/26.jpg)
![Page 27: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/27.jpg)
US Guidance for High Risk Muscles
• Diaphragm• Chest wall muscles
![Page 28: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/28.jpg)
Chest Wall Muscles
![Page 29: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/29.jpg)
High Risk Muscles
![Page 30: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/30.jpg)
Serratus Anterior
Normal side Atrophic side
![Page 31: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/31.jpg)
Diaphragm
![Page 32: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/32.jpg)
Needle Localization: Diaphragm
• Now use ultrasound for all cases• Identify safest interspace• Identify depth of diaphragm• Identify best side to examine
• Particularly helpful in obese patients, altered anatomy, COPD, Coumadin, severe atrophy
• Can use real time US guided needle placement when needed
![Page 33: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/33.jpg)
![Page 34: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/34.jpg)
Summary: US as a Localization Tool
• Easy to learn• Dynamic aspect plus knowledge
of anatomy• Patient may serve as control
• In cases of unilateral pathology• Many potential applications
![Page 35: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/35.jpg)
Summary: US application in EDX• Needle placement for accurate nerve
conduction studies• Needle placement for EMG of difficult
or higher risk muscles• Anatomic and pathophysiologic
information about nerve and muscle• Real time information on muscle
activation• Diaphragm function
![Page 36: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/36.jpg)
Summary
• EDX measures function, ultrasound evaluates structure
• The two are complementary in the EMG lab
• Highly portable• Relatively low cost• Constantly improving technology
![Page 37: Ultrasound to Enhance NCS and EMG - AANEM€¦ · • We studied bleeding risk post EMG • Risk of stopping A/C outweighs risk of EMG • Helped change our practice • Proceed with](https://reader034.fdocuments.in/reader034/viewer/2022052014/602c0f687ad600134f7d3a3c/html5/thumbnails/37.jpg)
Questions