Neelam Balasubramanian

Hearing Loss following Posterior Fossa Microvascular Decompression: A Systematic Review.

Objectives (1) Determine the prevalence of hearing loss following microvascular decompression (MVD) for trigeminal neuralgia (TN) and hemifacial spasm (HFS). (2) Demonstrate factors that affect postoperative hearing outcomes after MVD. Data Sources PubMed-NCBI, Scopus, CINAHL, and PsycINFO databases from 1981 to 2016. Review Methods Systematic review of prospective cohort studies and retrospective reviews in which any type of hearing loss was recorded after MVD for TN or HFS. Three researchers extracted data regarding operative indications, procedures performed, and diagnostic tests employed. Discrepancies were resolved by mutual consensus. Results Sixty-nine references with 18,233 operations met inclusion criteria. There were 7093 patients treated for TN and 11,140 for HFS. The overall reported prevalence of hearing loss after MVD for TN and HFS was 5.58% and 8.25%, respectively. However, many of these studies relied on subjective measures of reporting hearing loss. In 23 studies with consistent perioperative audiograms, prevalence of hearing loss was 13.47% for TN and 13.39% for HFS, with no significant difference between indications (P = .95). Studies using intraoperative brainstem auditory evoked potential monitoring were more likely to report hearing loss for TN (relative risk [RR], 2.28; P < .001) but not with HFS (RR, 0.88; P = .056). Conclusion Conductive and sensorineural hearing loss are important complications following posterior fossa MVD. Many studies have reported on hearing loss using either subjective measures and/or inconsistent audiometric testing. Routine perioperative audiogram protocols improve the detection of hearing loss and may more accurately represent the true risk of hearing loss after MVD for TN and HFS.

Surgical Results of Common Peroneal Nerve Neuroplasty at Lateral Fibular Neck

BACKGROUND Common peroneal nerve (CPN) compressive neuropathy is the most common lower-extremity entrapment neuropathy. MATERIALS AND METHODS A retrospective review of a prospectively maintained single-institution database of all patients with CPN palsy who underwent decompression and neuroplasty over a 5-year period was performed. RESULTS Thirty patients underwent a neuroplasty of the CPN over a 5-year period (2010-2015) at our institution. The median age was 45 years, and there was a male preponderance. The average time between first onset of symptoms to surgery was 122.9 weeks and between first clinic visit and surgery was 21 weeks. The etiology of the CPN neuropathy was as follows: in 12 patients, it followed a surgical procedure and in 14 patients, it occurred after a trauma to the lower extremity. In 2 patients, it occurred as a result of a mass lesion compromising the nerve and in 1 patient, a local infection predisposed to CPN palsy. Right and left lower extremities were equally involved. The median body mass index was 28.6. The most common presentation was weakness of the tibialis anterior (TA) and extensor hallucis longus (EHL) and loss of sensation in the distribution of the CPN or one of its major branches. Pain was a presenting symptom in 16 patients. Only 12 of the 30 patients had a positive Tinels sign at the site of compression over the lateral fibular neck. Preoperative electrophysiologic confirmation of CPN neuropathy was available in all patients. Mean follow-up was 52 weeks. Prone positioning and selective use of the operating microscope provided excellent visualization and surgical exposure of the CPN from the lower popliteal region to the peroneal tunnel. Average operating room time was 170 minutes and average skin-to-skin time 91 minutes. Clinical improvement after surgery in terms of motor function was noted in 24 of the 26 patients who presented with a motor deficit. The most consistent improvement was noted in the TA and EHL; a trend toward greater improvement with shorter time to surgery was noted. No complications related to the surgical site or CPN were encountered, and no patient had a decline in their neurologic examination as a consequence of the surgery. One patient developed a positioning-related right upper-extremity brachial plexus neuropraxic injury after surgery that recovered completely. CONCLUSIONS Common peroneal neuropathy usually presents with weakness of the TA and EHL and decreased sensation or pain in the distribution of the CPN. Microscope-assisted surgical neuroplasty of the CPN at the lateral fibular neck with the patient in a prone position allows decompression of the nerve from the lower popliteal region to the peroneal tunnel. Significant improvement in motor strength after surgery, particularly of the TA and EHL, was observed in this series.

Evaluation of Risk Factors for Clostridium difficile Infection in Hematopoietic Stem Cell Transplant Recipients

The primary objective was to determine the impact of hematologic malignancies and/or conditioning regimens on the risk of developing Clostridium difficile infection (CDI) in patients undergoing hematopoietic stem cell transplantation (HSCT). Secondary objectives were to determine if traditional CDI risk factors applied to patients undergoing HSCT and to determine the presence of CDI markers of severity of illness among this patient population.