Laser-Evoked Potentials to Pudendal Stimulation in Healthy Subjects: A Pilot Study.

PURPOSE: Laser-evoked potentials (LEPs) are useful neurophysiological tools for investigating the A-delta sensory peripheral fibers and the central nociceptive pathway. The current investigation aims to obtain normative values of LEPs via pudendal nerve stimulation in healthy adult volunteers. METHODS: Laser-evoked potentials were recorded in 16 men and 22 women, 22 to 75 years of age, using neodymium and yttrium and aluminum and perovskite laser bilateral stimulation to the pudendal nerve-supplied skin and the dorsal surface of the hands and feet. We assessed the perceptive threshold, latency, and amplitude of the N1 component and main vertex N2-P2 complex. The relationship between gender, age, height, and site of stimulation was statistically analyzed. RESULTS: Both in men and in women, laser perceptive threshold increased from genitalia to foot and from hand to foot (P ≤ 0.001). N1 and N2-P2 latencies progressively increased from pudendal area to hand to foot (P ≤ 0.008). N1 and N2-P2 complex LEP amplitudes progressively decreased from hand to genitalia to foot (P ≤ 0.04). The latencies of N1 component and N2-P2 complex of LEPs correlated with body height, whereas the amplitude of the N2-P2 complex correlated negatively with age; no correlations were observed between the latencies and amplitudes with gender. CONCLUSIONS: This study provides normative data on pudendal LEPs versus hand and foot LEPs. Incorporation of pudendal LEPs into clinical practice could provide a valuable neurophysiological tool for the study of pelvic pain syndromes.

A randomized controlled trial of IV immunoglobulin in patients with postpolio syndrome.

OBJECTIVE: To investigate in a single-center randomized control trial whether a single IVIg course improves short-term outcome in patients with postpolio syndrome (PPS). METHODS: Fifty-one patients with PPS were randomly allocated to receive 2g/kg IVIg body weight or placebo infused over 5 consecutive days. The primary endpoint was health-related quality of life (HRQoL) limited to the physical component score (PCS) in the Short-Form-36 (SF-36). Secondary endpoints included the SF-36 mental component score (MCS), 6-minute walk test, visual analog scale, 101-numeric rating, and fatigue severity scale. Muscle strength was graded according to the Medical Research Council scale and by dynamometer. Primary and secondary outcome variables were tested double-blind at baseline, 2months, and 4months. RESULTS: At two months, although SF-36 PCS scores were similar in both arms, the role physical (RP) domain improved significantly in the treatment arm (p=0.05) and so did the composite MCS (p=0.015), and role emotional (RE) subscale (p=0.02). No differences were found in the remaining outcome measures. At 4months, none of the outcome variables differed significantly between groups. CONCLUSIONS: Although the study did not reach the primary endpoint, we showed that a single IVIg course improves HRQoL related to mental activity, as measured by the SF-36 composite MCS, and role limitations including RP and RE SF-36 subscales at 2months, in patients with PPS. A single IVIg course leaves, gait, muscle strength, fatigue and bodily pain unchanged in patients with PPS. CLASSIFICATION OF EVIDENCE: Class I evidence indicates that IVIg did not change SF-36 PCS, and Class II evidence indicates that IVIg improved scores on the SF-36 MCS, RP, and RE.

Spread of botulinum neurotoxin type a at standard doses is inherent to the successful treatment of spastic equinus foot in cerebral palsy: short-term neurophysiological and clinical study.

To evaluate whether botulinum toxin type A at standard doses spreads to antagonist leg muscles in dynamic equinus foot, we studied 18 ambulatory children with hemiplegic cerebral palsy. The gastrocnemius muscle on the affected side was injected with botulinum toxin type A (Dysport) (mean ± standard deviation, 14.3 ± 0.9 U/kg). Compound muscle action potential areas were assessed in the lateral gastrocnemius and tibialis anterior muscles on the treated and untreated sides before botulinum toxin type A injections and on days 10 and 30 after injections. In all patients, compound muscle action potential areas recorded from both the muscles on the treated side decreased from preinjection values at day 10 (P < .05) and 30 (P < .002). After injection, ankle spasticity had diminished (P < .05), equinus foot excursion increased (P < .05), and functional gait improved (P < .05). This study shows that botulinum toxin type A spreads from foot flexors to antagonist extensors and suggests that spread may be partly responsible for improving gait in children with cerebral palsy.

Botulinum neurotoxin type A injections for vaginismus secondary to vulvar vestibulitis syndrome.

OBJECTIVE: To investigate whether botulinum neurotoxin type A improves vaginismus and study its efficacy with repeated treatments. METHODS: Outpatients were referred because standard cognitive-behavioral and medical treatment for vaginismus and vulvar vestibular syndrome failed. From this group, we prospectively recruited consecutive women (n=39) whose diagnostic electromyogram (EMG) recordings from the levator ani muscle showed hyperactivity at rest and reduced inhibition during straining. These women were followed for a mean (+/-standard deviation) of 105 (+/-50) weeks. Recruited patients underwent repeated cycles of botulinum neurotoxin type A injected into the levator ani under EMG guidance and EMG monitoring thereafter. At enrollment and 4 weeks after each cycle, women were asked about sexual intercourse; underwent EMG evaluation and examinations to grade vaginal resistance according to Lamont; and completed a visual analog scale (VAS) for pain, the Female Sexual Function Index Scale, a quality-of-life questionnaire (Short-Form 12 Health Survey), and bowel and bladder symptom assessment. RESULTS: At 4 weeks after the first botulinum neurotoxin type A cycle, the primary outcome measures (the possibility of having sexual intercourse, and levator ani EMG hyperactivity) both improved, as did the secondary outcomes, Lamont scores, VAS, Female Sexual Function Index Scales, Short-Form 12 Health Survey, and bowel-bladder symptoms. These benefits persisted through later cycles. When follow-up ended, 63.2% of the patients completely recovered from vaginismus and vulvar vestibular syndrome, 15.4% still needed reinjections (censored), and 15.4% had dropped out. CONCLUSION: Botulinum neurotoxin type A is an effective treatment option for vaginismus secondary to vulvar vestibular syndrome refractory to standard cognitive-behavioral and medical management. After patients received botulinum neurotoxin type A, their sexual activity improved and reinjections provided sustained benefits. LEVEL OF EVIDENCE: III.