Comparison between 18F-FDG PET/CT and EMG Mapping for Identifying Dystonic Superficial Muscles in Primary Cervical Dystonia: Preliminary Results

Abstract

Purpose This study was conducted to compare 18 F-FDG PET/CT and electromyography (EMG) mapping in patients with primary cervical dystonia (PCD) to find dystonic superficial cervical muscles. Methods Ten consecutive patients with PCD (M:F=5:5, age 44±13 years) whose dystonic posture was not relieved with conventional muscle relaxant therapy were included. Target cervical muscles for the comparison between 18 F-FDG PET/CT and EMG mapping were four representative superficial bilateral cervical muscles: splenius capitis muscle, sternocleidomstoid muscle, upper trapezius muscle, and leavator scapulae muscle. The diagnostic efficacy was compared between 18 F-FDG PET/CT and EMG mapping using physical exam and measurement of rotation angle as the gold standard. Results Among 80 muscles evaluated, there were 21 (26%) dystonic superficial cervical muscles assessed with physical exam and motion analysis. The sensitivity, specificity, and accuracy for localizing dystonic muscles were 76, 92, and 88% for 18 F-FDG PET/CT, and 95, 66, and 74% for EMG mapping, respectively. The sensitivity of EMG mapping was significantly higher than that of 18 F-FDG PET/CT. In contrast, 18 F-FDG PET/CT was significantly superior to EMG mapping for specificity and accuracy. Conclusions 18 F-FDG PET/CT is more specific and accurate than EMG mapping for finding superficial dystonic cervical muscles. The high sensitivity of EMG mapping suggests that 18 F-FDG PET/CT and EMG mapping are complementary for finding dystonic superficial cervical muscles.

Postoperative 18F-FDG-PET/CT documents efficacy of selective peripheral denervation for treating cervical dystonia

“…[4,5] Preoperatively and postoperatively, dystonic muscles are readily detected by 18 F-FDG PET/CT and SPECT/CT. [1][2][3] In the present case, an abnormal FDG uptake in the right obliquus capitis inferior was detected through preoperative 18 F-FDG-PET/CT. Following an SPD including an intradural rhizotomy of the anterior C1 and C2 nerve roots, the patient became asymptomatic.…”

“…Preoperatively and postoperatively, dystonic muscles can be identified utilizing 18F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/ computed tomography (PET/CT). [2,3] Here, a patient underwent selective peripheral denervation (SPD) followed by resolution of dystonia and 18 F-FDG-PET/CT findings thus confirming the effectiveness of the surgery.…”

Myotomy and Selective Peripheral Denervation Based on ¹⁸F-FDG PET/CT in Intractable Cervical Dystonia: A Case Report

“…13,15) The identification of dystonic muscles is essential for maximizing the efficacy of cervical dystonia treatment. 3) The dystonic muscles are identified based on clinical symptoms and physical examination; however, they can also be detected by EMG, 18 F-FDG PET/CT and SPECT/ CT. [5][6][7] Jang et al reported that the sensitivity, specificity, and accuracy of 18 F-FDG PET/CT for localizing dystonic muscles were 76%, 92%, and 88%, respectively. 5) In the present case, abnormal FDG uptake in the left obliquus capitis inferior was detected on preoperative 18 F-FDG PET/CT.…”

“… 4 ) 18F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) is a noninvasive modality that has been used to identify dystonic muscles in cervical dystonia. 5 , 6 ) Recently, single photon emission computed tomography (SPECT/CT) was reported to successfully identify dystonic muscles. 7 ) These examinations support the identification of dystonic muscles and increase the efficacy of BT injections.…”

Efficacy of single-photon emission computed tomography aided botulinum toxin injection in cervical dystonia: A double-blind, randomized study

“…However, it is an invasive technique and it does not help clinicians to predetermine the dystonic muscles [8].Other methods, such as sonography and computed tomography reflects only the anatomical structure of the muscle but not the function [9]. A Korean research group proved that 18 F-Fluorodeoxyglucose ( 18 F-FDG) positron emission tomography (PET/CT) could be useful for detecting dystonic muscles [10][11][12]. However, its use is limited by its accessibility and price.…”