A pilot study of a novel specs for chronic dizziness.

OBJECTIVE: A pilot study to assess the efficacy and safety of a novel specs device developed to alleviate chronic dizziness using eyeglasses with referential marks fixed on the lenses. MATERIALS AND METHODS: Forty patients with stable symptoms of chronic dizziness for more than 3 months participated in a 4-week, double-blind, randomized treatment with Active-Specs or Sham-Specs. Efficacy was assessed using validated semiquantitative scales and questionnaires of vertigo, dizziness and anxiety. Safety evaluation included monitoring of any adverse event. RESULTS: Thirty-six participants were included in the efficacy analysis, 18 in each group. Twelve of 18 subjects (67%) treated with Active-Specs reported substantial improvement of symptoms compared to six (33%) with Sham-Specs showing a significant improvement on Clinical Global Impressions scale (P = .017). The Active-Specs group showed significant reduction in the Vertigo Visual Analogue Scale (P = .017) and a nonsignificant but consistent trend of improvement measured by the Dizziness Handicap Inventory and Beck Anxiety Inventory. There were no adverse events related to the treatment. CONCLUSIONS: This novel specs device seems to be a safe and promising novel treatment for chronic dizziness. We hypothesize that marks in specific zones of the peripheral visual field could strengthen information of real head motion counteracting the mismatch sensory and locomotor information causing chronic dizziness. The results of this pilot study should be followed up by additional studies aimed at confirming the present encouraging findings.

Slower velocity perception with stronger optokinetic nystagmus: A paradoxical perception in virtual reality.

BACKGROUND: Optokinetic nystagmus (OKN) was studied in an immersive virtual reality (VR) environment with both typical optokinetic stimulation (OKs) wherein the head-tracking is active (similar to be sitting in front of a rotating drum) or a unique stimulus (VR-OKs) wherein the head-tracking is turned off, so head movements do not update the visual image (which moves with the head). OBJECTIVE: To study both the perception of the stimulus velocity and eye movements while subjects rotated their head from side to side and the visual scene was either a typical OKs or VR-OKs. METHODS: 9 healthy participants (aged 23 ± 2.4 y/o) had head and eye movements recorded under typical OKs and VR-OKS while smoothly rotating their head horizontally from side to side. Stimulation was delivered using a virtual reality setup on top of an eye movements recording system. RESULTS: Under VR-OKs participants perceived faster stimulus velocity when the head and stimulus had the same direction as compared to the head and stimulus in opposite directions. When the head turned in the same direction as the stimulus, there were fewer fast phase eye movements than when it rotated counter to stimulus motion direction. Conversely, with typical OKs, participants perceived faster stimulus velocity when the head and stimulus had opposite directions as compared to the head and stimulus having the same direction. CONCLUSIONS: The seemingly paradoxical results in which slower stimulus velocity is perceived in tandem with stronger nystagmus can be explained by the simultaneous activation of the Vestibulo-Ocular Reflex and OKN in accordance with the various visual and vestibular stimuli.

Overview of guidelines for establishing a face transplant program: a work in progress.

Since 2005, nine face transplants have been performed in four countries: France, the United States (US), China and Spain. These encouraging short-term outcomes, with the longest survivor approaching 5 years, have led to an increased interest in establishing face transplant programs worldwide. Therefore, the purpose of this article is to facilitate the dissemination of relevant details as per our experience in an effort to assist those medical centers interested in establishing a face transplant program. In this article, we address the logistical challenges involved with face transplantation; including essential program requirements, protocol details, face transplant team assembly, project funding, the organ procurement organization and the coroner. It must be emphasized that face transplantation is still experimental and its therapeutic value remains to be validated. All surgical teams pursuing this endeavor must dedicate an attention to detail and should accept a responsibility to publish their outcomes in a transparent manner in order to contribute to the international field. However, due to its inherent complexity, facial transplantation should only be performed by university-affiliated medical institutions capable of orchestrating a specialized multidisciplinary team with a long-term commitment to its success.

Composite tissue allotransplantation: a proposed classification system based on relative complexity.

Numerous achievements have been made encompassing a wide array of composite tissue allograft (CTA) subtypes. We sought to develop a simple, reproducible CTA classification system for the purpose of comparing clinical investigation. Each CTA subtype differs in relative complexity and can therefore be theoretically classified based on its unique combination of multiple factors. Eight complexity factors (CFs) are hypothesized: anatomic detail, psychological obstacles, rejection risk, required rehabilitation, relative antigenicity, functionality/cosmesis, skin ratio, and salvageability. A distribution of total complexity scores, ranging from 8 to 24, is classified into 3 ordered categories representing varying degrees of complexity. In conclusion, we have created a new classification system so that ongoing research and future data may be compared in a type-specific fashion.

Vestibulo-ocular reflex dynamics with head-impulses discriminates spinocerebellar ataxias types 1, 2 and 3 and Friedreich ataxia.

OBJECTIVE: Although the diagnosis of inherited ataxias is ultimately genetic, this usually means an extensive and expensive process. This justifies the search for distinct clinical signs that may potentially help orient molecular diagnosis. METHODS: We explored the vestibulo-ocular reflex (VOR) with the video Head Impulse Test in patients diagnosed with spinocerebellar ataxia (SCA) type 3 (n = 15), type 1 (n = 4) and type 2 (n = 4), Friedreich's ataxia (FA) (n = 9) and healthy controls (n = 40). We estimated the latency, regression (VORr) and instantaneous VOR gain at 40, 60 and 80 ms (VOR40, VOR60 and VOR80), and determined the latency, peak-velocity and occurrence rate of catch-up saccades triggered with head-impulses. RESULTS: VOR latency was higher in FA (p < 0.001) and SCA3 (p = 0.02) as compared to controls, discriminating FA from other ataxic patients with an overall diagnostic accuracy of 88%. VORr, VOR40 and VOR60 were significantly lower in FA and SCA3 (p < 0.01). VOR80 was only significantly lower than controls in SCA3 (p < 0.01), discriminating these from other ataxic patients with an overall diagnostic accuracy of 78%. Covert saccades were only triggered in SCA3 but with low occurrence rate and peak velocity (11.1 ± 28.5% and 77.50 ± 15.30°/s) whereas overt saccades were present in all groups. VORr gain showed a negative correlation with disease severity evaluated with SARA (Spearman r = -0.46, p = 0.01). CONCLUSIONS: vHIT provides phenotypic information that differentiates these autosomal ataxias and can serve as a strategy to orient genetic diagnosis. A correlation between VOR and SARA raises the possibility of using VOR gain as a neurophysiologic biomarker for disease severity.

Cinnarizine in the prophylaxis of seasickness: laboratory vestibular evaluation and sea study.

Cinnarizine was evaluated for the prevention of seasickness in a laboratory and sea study. The effects of 25 mg cinnarizine on the vestibulo-ocular reflex were investigated in 13 subjects. Significant reduction of the gain in response to sinusoidal oscillations at 0.02, 0.08, and 0.16 Hz (p < 0.05) and increased phase lead at 0.16 Hz (p < 0.01) were observed. The effect of 25 and 50 mg cinnarizine on seasickness severity was examined in 95 subjects during a voyage in rough seas. Seasickness symptoms were improved in 69% of the subjects by 50 mg cinnarizine versus 35% and 31% in the groups receiving 25 mg cinnarizine and placebo (p < 0.05 and p < 0.01, respectively). The percentage of vomiting protection provided by 50 mg cinnarizine was 63% (p < 0.05). We conclude that 50 mg cinnarizine is an effective drug for the prevention of seasickness. The reduction in vestibular sensitivity observed even after administration of 25 mg cinnarizine may explain the potency of cinnarizine in the prevention of seasickness.

Spinal cord decompression sickness in sport diving.

OBJECTIVE: To summarize 16 years' experience in the diagnosis and treatment of spinal cord decompression sickness in Israel. DESIGN: The survey data were collected firsthand by physicians trained in underwater diving medicine. SETTING: The Israeli Naval Medical Institute, Israel's national hyperbaric referral center. PATIENTS: Sixty-eight sport divers diagnosed as having spinal cord decompression sickness. INTERVENTIONS: Hydration and 100% oxygen breathing until the patient reached the hyperbaric chamber. All patients received recompression therapy on US Navy treatment tables using oxygen, except for six who were treated by Comex Treatment Table CX-30, which uses helium in addition to oxygen. MAIN OUTCOME MEASURES: Neurological examination after the completion of recompression therapy. RESULTS: Forty-one percent of the dives were performed within the decompression limits of the US Navy standard decompression tables. Risk factors were fatigue, circumstances suggesting dehydration, and extreme physical effort. The most common presenting symptoms were paresthesias, weakness of the legs, lower back pain, or abdominal pain. Full recovery was achieved in 79% of the patients. Spinal symptoms appeared immediately on surfacing in six of the eight patients who continued to have multiple neurological sequelae. CONCLUSIONS: United States Navy air decompression tables appear not to be completely safe for sport divers. Even mild spinal symptoms identified on surfacing should be treated vigorously. High-pressure oxygen-helium therapy seems to be a promising alternative in cases of severe spinal cord decompression sickness.

Open controlled therapeutic trial of intravenous immune globulin in relapsing-remitting multiple sclerosis.

Ten patients with relapsing-remitting multiple sclerosis were treated with intravenous immune globulin, 0.4 g/kg per day for 5 consecutive days, and then with additional booster doses of immune globulin of 0.4 g/kg, once every 2 months, for the next 12 months. Ten untreated patients with relapsing-remitting multiple sclerosis who were matched with the study patients for age, disease duration, and number of attacks per year served as controls. Immune globulin treatment was well tolerated, with no side effects. The exacerbation rate decreased from 3.7 +/- 1.2 exacerbations per year before treatment to 1.0 +/- 0.7 exacerbations per year during the treatment in the immune globulin-treated patients, while it remained unaltered in the controls. The posttreatment Kurtzke Expanded Disability Status Scale score decreased from a mean of 4.45 to 4.15, whereas in controls it increased from 3.55 to 3.75. The results suggest that immune globulin suppresses the ongoing pathologic process in multiple sclerosis and may be a promising treatment to prevent disease exacerbations.

Is the stepping test a specific indicator of vestibulospinal function?

We studied the effect of walking on a horizontally rotating disk (circular treadmill) on the stepping test in seven normal subjects. Subjects walked for 2 hours on the perimeter of the treadmill with eyes open while remaining stationary in space. Then, off the treadmill, they attempted to step in place with eyes closed for 50 paces without turning. All subjects exhibited post-treadmill turning in the same direction as that of the previous walking relative to the treadmill. Post-treadmill average angular velocities were 207 to 880 deg/min greater than pretreadmill values. No subject experienced any sensation of motion relative to ground or space. The stepping test may no longer be considered a specific indicator of vestibulospinal function.

The effects of boron neutron capture irradiation on oral mucosa: evaluation using a rat tongue model.

The ventral surface of the tongue of male Fisher 344 rats was used to evaluate the response of oral mucosa to boron neutron capture irradiation. Three hours after i.p. injection of 700 mg/kg of the boron delivery agent p-boronophenylalanine (BPA), the boron concentrations in blood and tongue mucosal epithelium were approximately 21 and 23 microgram (10)B/g, respectively. The doses required to produce a 50% incidence of ulceration with X rays, the Brookhaven Medical Research Reactor thermal neutron beam alone, or the thermal neutron beam in the presence of BPA were 13.4 +/- 0.2, 4. 2 +/- 0.1, and 3.0 +/- 0.1 Gy, respectively. Ulceration of the tongue was evident by 6 to 7 days after irradiation, irrespective of the irradiation modality; healing was related to dose and was relatively rapid (

Dissociation between sleep-related and TRH-induced prolactin secretion in seminiferous tubule failure.

Prolactin (PRL) secretion has been measured during sleep and following TRH administration in 8 patients aged 24-39 yr with seminiferous tubule failure and 36 controls. Basal LH levels were 25.7 +/- 14.7 mIU/ml in the patients compared to 11.5 +/- 4.2 mIU/ml in the controls (p less than 0.01) Corresponding FSH levels were 26.2 +/- 10.7 mIU/ml and 5.9 +/- 2.1 mIU/ml (p less than 0.001) Mean estradiol 17B and testosterone levels were similar in the 2 groups. The mean PRL secretion during sleep was 16.5 +/- 11.7 ng/ml in the patients and not different in 11 of the controls (12.4 +/- 3.2 ng/ml). One patient had a mean nocturnal PRL concentration of 44.1 ng/ml. In both groups, the mean sleep related PRL concentration was greater than that during waking hours. The average number of peaks in the 2 groups was similar. In the same patients, the peak PRL response to TRH (200 ug IV) was 81.9 +/- 18.8 ng/ml as compared to 32.1 +/- 10.7 ng/ml in the controls (p less than 0.001). It is concluded that PRL concentrations following pharmacological stimulation are increased in seminiferous tubule failure, whereas levels are normal in relation to the physiological stimulus of sleep.

Physical and biological doses produced from neutron capture in a 235U foil.

As a follow-on study to the feasibility of neutron capture therapy (NCT) with 235U brachytherapy seeds, physical doses were calculated and measured for the radiation from a 235U foil in a lucite phantom which was irradiated at the epithermal neutron irradiation port of the Brookhaven Medical Research Reactor. In addition, cell survival experiments were performed to obtain the relative biological effectiveness (RBE) for the neutron part of the radiation. The calculated absorbed doses agree with the measured ones. From cell survival experiments, it is deduced that the fission neutrons from the 235U foil have a RBE of 3.0 while the fast neutrons in the beam have a RBE of 3.8. Also observed is that, with the cells 7 mm from the foil, a significant amount of absorbed dose comes from the beta rays of 235U fission events. This absorbed dose from beta rays is a significant addition to the therapeutic dose. Due to the limited ranges of beta rays in tissue, this absorbed dose is restricted to the vicinity of the foil. This is the first demonstration of beta rays as part of NCT.

Effect of adrenergic blockers on the dog's sleep-wake pattern.

Different results are reported for the effects of an alpha and beta adrenergic blocker on the 24-hr sleep-wake patterns in dogs. While propranolol did not affect the 24-hr sleep-wake parameters, phentolamine significantly reduced delta sleep (stage 2), shortened the length of the sleep episodes, and decreased the number of REM episodes in each sleep-wake cycle. Phentolamine effects are explained by increased arousals within sleep episodes.

Day-night variations in urine excretions and hormones in dogs: role of autonomic innervation.

Under controlled light-dark cycle (LD 12:12) and two hydratory conditions, mongrel dogs display marked day-night variations in urine flow and in its constituents. Diurnal peaks were found in urine flow and sodium excretion, while nocturnal peaks were observed in osmolality and potassium excretion. Diuretic responses, after fluid intake, were consistently faster and higher during the day than during the night. Nocturnal increases were found in plasma antidiuretic hormone (ADH), in aldosterone and in plasma renin activity (PRA), which could partially explain the present results. In all dogs there was a decrease in ADH level in the early morning hours which could account for the increased urine flow and decreased osmolality observed at this time. Plasma cortisol did not show significant temporal variations throughout the 24-hour period. Kidney denervation did not alter the day-night variations in urinary flow, sodium and osmolality, but affected the pattern of potassium excretion. A neural control of potassium excretion pattern, probably mediated by PRA-aldosterone is tentatively postulated.

The effects of dimenhydrinate, cinnarizine and transdermal scopolamine on performance.

We assessed the influence of dimenhydrinate, cinnarizine and transdermal scopolamine on the ability to perform simulated naval crew tasks. The effect of single doses of dimenhydrinate, 100 mg, cinnarizine, 50 mg, and one transdermal scopolamine patch on psychomotor performance was evaluated using a double-blind, placebo-controlled, randomized, crossover design in three separate studies. A total of 60 young naval crew (20 for dimenhydrinate, 15 for cinnarizine and 25 for transdermal scopolamine) underwent a battery of computerized and paper and pencil performance tests, and filled out a questionnaire on side-effects and well-being self-assessment. Dimenhydrinate significantly impaired decision reaction time and auditory digit span. Most of the subjects who took dimenhydrinate also reported a subjective decrease in well-being and general performance abilities. Cinnarizine and transdermal scopolamine did not affect performance abilities. Cinnarizine was free of significant side-effects. Dry mouth was the only significant side-effect of transdermal scopolamine. These findings could be explained by the well-known sedative properties of dimenhydrinate and not by a specific effect on any particular cognitive or motor function. Our results suggest that dimenhydrinate, 100 mg, adversely affects psychomotor function, whereas single doses of cinnarizine, 50 mg, and transdermal scopolamine appear to be free of side-effects on performance and seem to be a preferable anti-seasickness drug for use by a naval crew.

Characterization of genetic instability in radiation- and benzene-induced murine acute leukemia.

This study, using the CBA/Ca mouse as a model, compares genetic lesions associated with radiation- and benzene-induced acute leukemias. Specific types of leukemia included in the analyses are radiation-induced acute myeloid leukemia (ML), and benzene-induced lymphoblastic leukemias, lymphomas, or mix-lineage leukemias. These leukemias have histopathological characteristics similar to those seen in human acute leukemias. G-band cytogenetic analysis showed that specific deletions involving regions D-E of one copy of mouse chromosome 2 [del(2)(D-E)] were frequently associated in both radiation- and benzene-induced acute leukemias. In addition, translocations of chr2(D-E) were also observed in some cases. These results suggest an important role of chr2 (D-E) deletions and translocations in the development of radiation- and benzene-induced murine acute leukemias. Fluorescence in situ hybridization with DNA probes specific for 2(D-E), constructed in our laboratory by means of chromosomal microdissection and PCR amplification, also demonstrate 2(D-E) deletions and/or translocations in these leukemic cells. Aneuploidy of chromosomes 3, 15, 16, and Y were also frequently detected in benzene-induced leukemic cells with or without lesions on chr2. These cytogenetic findings support the previous observations that metabolites of benzene lead to spindle-fiber disruption or abnormal cytokinesis in exposed animals. In summary, genetic instabilities observed in leukemic cells isolated from mice that had developed leukemia after exposure to radiation or benzene are syntenic with those frequently detected in patients with myelodysplastic syndrome, acute ML, and acute lymphoblastic leukemia. Thus, the CBA/Ca mouse has several characteristics that make it an excellent model for the study of radiation or benzene leukemogenesis in humans.

Diving-related inner ear injuries.

Diving-related inner ear barotrauma (IEB) and inner ear decompression sickness (IEDS) most often result in permanent severe cochleovestibular deficits, unless immediate diagnosis is reached and the correct treatment is commenced early. Nine cases of sport-diving-induced inner ear injuries that were referred to the Israeli Naval Hyperbaric Institute between October 1987 and September 1989 are presented with regard to evaluation, treatment, and follow-up. The diagnosis was IEB in five divers and IEDS in four. Explorative tympanotomy was carried out with remarkable results in two patients with IEB, while the remaining three were relieved by bed rest alone. Three of the four IEDS patients were recompressed according to the extended US Navy Table 6 with good short-term results. The role of complete otoneurological evaluation in the decision-making process leading to the correct diagnosis and treatment is emphasized.

Inner ear decompression sickness in sport compressed-air diving.

OBJECTIVE: We report our experience over the past 12 years with recreational diving-related inner ear decompression sickness (IEDCS). STUDY DESIGN: Retrospective, consecutive case series. METHODS: Twenty-four divers, representing 29 cases of IEDCS, are presented with regard to evaluation, treatment, and follow-up. RESULTS: These 29 cases represent 26% of the severe decompression sickness (DCS) cases treated in that period. The patient group includes 22 divers who had a single event of IEDCS, one diver who had two events, and one with five repeated episodes. The cause of injury in 23 cases (79%) was violation of the decompression schedule. The mean time from surfacing to appearance of symptoms was 47 +/- 65 minutes. In 83%, symptoms appeared within 1 hour of ascent, in 97% within 2 hours, and in only one diver after 5.5 hours. Ten divers (34%) had pure vestibular involvement, 4 (14%) had cochlear insult alone, and 15 (52%) had combined vestibulo-cochlear injury. Except for one patient who had central as well as peripheral vestibulo-cochlear DCS, all the remaining patients had end organ involvement only, as demonstrated by physical examination and laboratory test results. Fifteen (52%) had isolated IEDCS, whereas 14 had additional symptoms of DCS. Twenty-six cases were treated by hyperbaric oxygenation with supplementary daily hyperbaric sessions. Of the 25 cases with vestibular injury and the 19 with cochlear damage, only 7 (28%) and 6 (32%), respectively, made a full recovery, whereas the others remained with residual damage. Of the 17 treated within 6 hours of symptom appearance, 9 (53%) were cured, compared with one of the 9 treated later (P <.05). CONCLUSIONS: IEDCS related to compressed-air recreational diving is more common than previously thought, and might occur even when no decompression schedule violation took place. Prompt diagnosis leading to the early commencement of hyperbaric oxygen recompression therapy is the key to complete recovery of cochlear and vestibular function.

Three modality evoked potentials in Charcot-Marie-Tooth disease (HMSN-1).

Sixteen patients with dominant hereditary motor-sensory neuropathy type I (HMSN I), members of 5 families, underwent trimodality evoked potential studies. All patients had clinically normal optic nerves. History of deafness was present in 3 patients and sensory-neural hearing defect was found in 5 of 7 patients in whom audiometry was obtained. In 43.7 percent of the subjects significant prolongation of P100 of the VEP was found. Prolongation of N19 of the SEP was found in all 12 subjects examined. Significant bilateral prolongation of peak I of the ABEP was found in 37.5 percent of the subjects and in 50 percent of the ears examined: these findings indicated that in addition to peripheral nerves, the myelin of the optic and cochlear nerves is also affected in HMSN type I.

Mucolipidosis III and Bardet-Biedl syndrome in the same family: diagnostic pitfalls.

Two brothers, offspring of an Arab inbred family suffered from both mucolipidosis III (ML-III) and Bardet-Biedl syndrome (BBS). Other members of this family were affected either with ML-III, or with BBS. It seems that this unique combination is probably coincidental.