Psychiatry 1995;58:692-698)

R1 and R2 blink reflex responses to single and paired stimuli were investigated in 23 control subjects: 21 patients with blepharospasm (BSP), 20 patients with torticollis spasmodica (TS), and 23 with hemifacial spasm (HFS). For paired stimuli, we compared measurements of area and peak responses at two and three times R2 threshold. R1 and R2 indices were calculated as the average of the recovery values at 0.5‐, 0.3‐, and 0.21‐s interstimulus intervals to test individual patients. Peak amplitude measurements at three times R2 threshold were optimal. The R2 index was abnormal in 67% of BSP patients, 37% of TS patients, and 50% of HFS patients on the affected side and 20% on the unaffected side. A normal R2 index in one third of patients with BSP may indicate that different pathophysiological mechanisms are involved in this type of focal dystonia. © 1996 John Wiley & Sons, Inc.

We compared various electrodiagnostical tests in patients with hemifacial spasm and in patients who developed synkinesia after Bell’s palsy. We examined the evoked blink reflexes in the orbicularis oculi (o. oculi) and orbicularis oris (o. oris) muscles in 23 patients with hemifacial spasm (HFS), in 10 patients with synkinesia after Bell’s palsy (BPS) and in 22 control subjects. In the patient groups, we recorded synkinesia, latency and amplitude of compound muscle action potential (CMAP) in the mental muscle after stimulation of the facial nerve and we examined electromyographic activity of the o. oculi and mental muscles synchronously. Furthermore, we studied the phenomenon of lateral spreading, also known as ephaptic transmission, between the different facial nerve branches. Patients with BPS had a prolonged R1 latency on the affected side in o. oculi and smaller mental CMAP amplitude as an indication of facial nerve damage and nerve fiber loss. This was not found in patients with HFS, who showed an increased amplitude of the R1 and R2 responses in o. oris. Patients with BPS showed only an increased R1 amplitude in o. oris. All patients had signs of synkinesia. Lateral spreading with different patterns was present in all patients with HFS and in half of the patients with BPS. Latencies of early and late responses showed no differences between HFS and BPS. In addition to alterations in facial nucleus excitability in both conditions, ectopic re-excitation of facial nerve axons in HFS may explain the differences in neurophysiological findings between HFS and BPS patients. A loss of control following synaptic stripping may also be a contributing factor.

No abstract

ObjectIn patients with focal nerve injury and neuropathic pain cutting the nerve to obtain permanent pain reduction can be considered. Surgery is indicated only if a diagnostic nerve block provides temporary pain relief. We evaluated the predictive value of a block on the outcome of surgery.MethodsIn total, three blocks were performed at two week intervals. Patients were blinded to injections containing lidocaine 1% and a placebo was included. Surgery was offered regardless of the effect of the blocks. Twenty-four patients received 72 blocks. Sixteen patients opted for surgery, 5 patients refrained from surgery, and in 3 the blocks provided permanent pain relief. The predictive ability of the block on the outcome of surgery was assessed by calculating the area under a Receiver Operating Characteristic curve (AUC).ResultsThe AUC of the first lidocaine block was 0.35 with a 95% confidence interval from 0.077 to 0.62. At 95% confidence (two-sided), the AUC is less than 0.62, and hence the predictive ability of the block was poor. The outcome of the second lidocaine block and saline block did not change the conclusion of the first block.ConclusionsWe conclude that the use of blocks to select patients for surgery should be critically appraised.PerspectiveA pain relieving response to one open block is currently considered mandatory before patients with focal nerve injury and neuropathic pain are offered surgery. Blinded blocks including a placebo show that responses for selection should be carefully interpreted because they may not be as predictive as generally presumed.

The aim of this work was to investigate whether the nor mal use of colloidal bismuth subcitrate (CBS) and bismuth subnitrate (BSN) exhibits neurotoxic side-effects. A ran domised, single-blind controlled study was carried out in 66 patients with H. pylori associated gastritis. Patients were randomised to receive either amoxicillin (control group) for 4 weeks or BSN for 8 weeks or CBS for 8 weeks. Clinical and neurophysiological tests including elec troneurography (ENG) and spectral electroencephalogra phy (EEG) were performed before and after therapy. No clinically relevant changes were observed with clinical tests as well as with ENG and spectral EEG recordings within each group and between the groups. It was con cluded that the normal use of CBS and BSN does not exhibit clinical neurotoxicity.

OBJECTIVEThe results of lateral femoral cutaneous nerve (LFCN) decompression to treat idiopathic meralgia paresthetica (iMP) vary widely. Techniques to decompress the LFCN differ, which may affect outcome, but in MP it is unknown to what extent. The authors present a new technique using dynamic decompression and discuss the outcomes.METHODSA retrospective cohort study was performed in a consecutive series of 19 cases. The goal of decompression was pain relief and recovery of sensation. The plane ventral to the LFCN was decompressed by cutting the fascia lata and the inferior aspect of the inguinal ligament. The plane dorsal to the LFCN was decompressed by cutting the fascia of the sartorius muscle. Subsequently, the thigh was brought in full range of flexion and extension/abduction. The authors identified and additionally cut fibers that tightened and caused compression at various locations of the LFCN during movement in all patients, referring to this technique as dynamic decompression. Postoperatively, an independent neurologist scored pain and sensation on a 4-point scale: completely resolved, improved, not changed, or worsened. Patients scored their remaining pain or sensory deficit as a percentage of the preoperative level. Statistical assessment was done using ANOVA to assess the association between outcome and duration of preoperative symptoms, BMI, and length of follow-up.RESULTSIn 17 of the 19 cases (89%), the pain and/or paresthesia completely resolved. Patients in the remaining 2 cases (11%) experienced 70% and 80% reduction in pain. Sensation completely recovered in 13 of the 19 cases (69%). In 5 of the 19 cases (26%) sensation improved, but an area of hypesthesia remained. Four of these 5 patients indicated a sensory improvement of more than 75%, and the remaining patient had 50% improvement. Sensation remained unchanged in 1 case (5%) with persisting hypesthesia and mild hyperesthesia. There was no significant impact of preoperative symptom duration, BMI, and length of follow-up on postoperative outcome.CONCLUSIONSDynamic decompression of the LFCN is an effective technique for the treatment of iMP. Most patients become completely pain free and sensation recovers considerably.

OBJECTIVE Little is known about optimal treatment if neurolysis for ulnar nerve entrapment at the elbow fails. The authors evaluated the clinical outcome of patients who underwent anterior subcutaneous transposition after failure of neurolysis of ulnar nerve entrapment (ASTAFNUE). METHODS A consecutive series of patients who underwent ASTAFNUE performed by a single surgeon between 2009 and 2014 was analyzed retrospectively. Preoperative and postoperative complaints in the following 3 clinical modalities were compared: pain and/or tingling, weakness, and numbness. Six-point satisfaction scores were determined on the basis of data from systematic telephonic surveys. RESULTS Twenty-six patients were included. The median age was 56 years (range 22–79 years). The median duration of complaints before ASTAFNUE was 23 months (range 8–78 months). The median interval between neurolysis and ASTAFNUE was 11 months (range 5–34 months). At presentation, 88% of the patients were experiencing pain and/or tingling, 46% had weakness, and 50% had numbness of the fourth and fifth fingers. Pain and/or tingling improved in 35%, motor function in 23%, and sensory disturbances in 19% of all the patients. Improvement in at least 1 of the 3 clinical modalities was found in 58%. However, a deterioration in 1 of the 3 modalities was noted in 46% of the patients. On the patient-satisfaction scale, 62% reported a good or excellent outcome. Patients with a good/excellent outcome were a median of 11 years younger than patients with a fair/poor outcome. No other factor was significantly related to satisfaction score. CONCLUSIONS A majority of the patients were satisfied after ASTAFNUE, even though their symptoms only partly resolved or even deteriorated. Older age is a risk factor for a poor outcome. Other factors that affect outcome might play a role, but they remain unidentified. One of these factors might be earlier surgical intervention. The modest results of ASTAFNUE should be mentioned when counseling patients after failure of neurolysis of ulnar nerve entrapment to manage their expectations. Patients, especially those who are elderly, might even consider not undergoing a secondary procedure. A randomized trial that includes a conservative treatment group and groups undergoing one of the several possible surgical procedures is needed to find the definitive answer for this clinical problem.