Pittsburgh, August 8, 2026 — Lindsay Bhandari, MD, of the University of Pittsburgh Department of Neurological Surgery is first author of the chapter "Abnormal Muscle Recording" in Operative Neurophysiology: Practical Application for Comprehensive Neuromonitoring and Neuromapping Techniques, released by Springer in April 2026. She wrote the chapter with department colleagues Katherine Anetakis, MD; Donald Crammond, PhD; Parthasarathy Thirumala, MD, MS; and Jeffrey Balzer, PhD, the corresponding author, along with R. Joshua Sunderlin, MS, and Varun Shandal, MD.
The chapter examines the abnormal muscle response (AMR), also known as the lateral spread response, an electromyographic signal recorded from facial muscles in patients with hemifacial spasm. Its disappearance during microvascular decompression offers real-time physiologic evidence that the facial nerve has been successfully decompressed. The authors review the history and pathophysiology of the response, its value in predicting surgical outcomes, techniques for eliciting and troubleshooting the recording, anesthetic considerations, and complementary modalities such as the blink reflex.
Dr. Thirumala directs the UPMC Center for Clinical Neurophysiology and the Clinical Neurophysiology Laboratory, and Dr. Balzer serves as director of clinical operations at the center. Both have published extensively on lateral spread monitoring, including a series of 293 patients undergoing microvascular decompression and a systematic review and meta-analysis of the technique.
Edited by Justin W. Silverstein, DHSc; Randy S. D'Amico, MD; and Jason A. Ellis, MD, of Lenox Hill Hospital, the 39-chapter volume covers intraoperative monitoring and mapping across supratentorial, cerebrovascular, skull base, spine, and peripheral nerve surgery.
