Novel Use of Transcranial MEP and SSEP in a Case of Sciatic Nerve Tumor

Abstract

Inclusion Criteria: Age between 18and 65 years. Patients undergoing clipping, coiling for anterior circulation aneurysm with WFNS grade III, IV, and V. ICU admission within 48 to 72 hours of surgery.Exclusion Criteria: Patient not giving consent. Contraindication for application of NIRS sensors (pneumocephalus). Data of rSO 2 , SjvO 2 , and CBFV were collected at the following time points-arrival in the ICU (baseline), second hourly daily during the ICU stay (up to 5 days) prior to and after intervention. The significant changes were recorded.Results: Injured side NIRS values were less compared with normal side. Injured side TCD values were always higher by > 25 cm/sec. The side-side differences existed for NIRS and TCD. The trend values were similar in all patients and consistent.Conclusion: Interhemispheric differences in rSO 2 and TCD could be considered as an early sign of VS-induced DCI rather than absolute threshold values. However, large studies are needed to test our observations. Introduction: Von Hippel-Lindau (VHL) disease is an inherited autosomal dominant disorder with predilection to develop characteristic tumors in the cerebellar hemispheres, retina, brain stem, and spinal cord with a prevalence of approximately 1/50,000. KeywordsMethodology/Description: A 29-year-old, 55-kg woman presented with tingling and numbness in all four limbs, difficulty in walking, constipation, and urge for micturition. MRI revealed multiple cystic enhancing lesions in cervical and dorsal cord with significant cord edema. Diagnosed with VHL disease, pancreatic cyst, and diabetes mellitus for past 5 years on treatment. Multiple hemangiomas in retina. Operated for right partial nephrectomy 5 years back. Patient had a Glasgow Coma Scale (GCS) of 15/15 preop. Power of 4/5 on right side, 5/5 on left side. Routine hematological, biochemical values, thyroxin, cortisol, chest X-ray, serum electrolytes, calcium and phosphorus levels, 12-lead electrocardiogram, and echocardiogram were normal. Patient was posted for cervical laminectomy and intramedullary cyst excision from C2 to C7 level. Routine monitors were attached, left radial artery was cannulated. Patient induced with inj. midazolam, fentanyl, propofol, and atracurium. Anesthesia maintained with oxygen-air mixture with sevoflurane (<0.5 MAC), dexmedetomidine, and propofol infusion. Intraop neuromonitoring-somatosensory evoked potential (SSEP), motor evoked potential (MEP), bispectral index, neuromuscular monitoring done. MEP-amplitude decreased < 50 intraoperatively with baseline values, while SSEP were maintained. Postoperatively, patient had right upper and lower limb power grade 0/5, which improved significantly by POD-3 to preop level 4/5. Patient was discharged on POD-8.Conclusion: There is very little literature available for anesthetic management in a VHL disease. Anesthetic management of VHL is by itself a challenge; this case was more challenging due to the presence of cervicodorsal and pancreatic cyst with multiple hemangiomas. The case was successfully managed b...