Effect of chronic cortical stimulation on chronic severe tinnitus: a prospective randomized double-blind cross-over trial and long-term follow up.

BACKGROUND: Chronic severe tinnitus can be greatly detrimental to quality of life. Some authors have reported benefit of repetitive transcranial magnetic stimulation, others of electrical cortical stimulation by stimulating the Heschl's gyrus or secondary auditory areas. OBJECTIVE: To evaluate the efficacy of chronic electrical epidural stimulation of the auditory cortex on severe and disabling tinnitus. METHOD: In this double-blind randomized cross-over, patients with chronic (at least 2 years), severe (Strukturierte Tinnitus-Interview, STI score > 19), unilateral or strongly lateralized tinnitus were included. After open-phase stimulation for 4 months, patients were randomized into 2 groups for double-blind stimulation with cross-over between significant and non-significant phases and wash-out in between. Each of the 3 phases was 2 weeks in duration. Patients were chronically stimulated and followed if not explanted. A decrease of STI score >35% was considered as clinically significant. RESULTS: None of the 9 patients included achieved significant improvement during the double-blind phase. Four were explanted, 2 owing to lack of effect, one for breast cancer under the stimulator, and another for psychiatric decompensation. Five are still stimulated. Three felt slight to great subjective effectiveness, the remaining 2 reported benefits and still requested stimulation. CONCLUSIONS: This study did not find an objective efficiency of chronic cortical stimulation for severe and resistant tinnitus. The discordance between the results in double-blind and open evaluations could be related to a placebo effect of surgery, but may also be explained by a poorly defined target, a too short randomized phase, or inappropriate outcome measures. Clinical trial reference: NCT00486577.

Risk factors for the occurrence of electroencephalogram abnormalities during induction of anesthesia with sevoflurane in nonepileptic patients.

BACKGROUND: The aim of this prospective study was to determine the risk factors of epileptiform discharge during induction with sevoflurane in healthy adult patients. METHODS: Forty adult patients with American Society of Anesthesiologists physical status I were randomly allocated to one of four groups. Group A: Patients breathed 8% sevoflurane in oxygen (8 l/min) via a prefilled circuit. End-tidal sevoflurane was maintained at 4%. Tracheal intubation was performed at the third minute after cisatracurium injection. Group B: The anesthesia protocol was similar, but a vital capacity technique was performed. Group C: Patients were anesthetized as in group A but were hyperventilated. Group D: Patients were anesthetized as in group A, but end-tidal sevoflurane was maintained at 2%. An electroencephalogram was recorded before and during induction up to 11 min after the start of induction. Statistical analysis was performed with Statview 5.0 (SAS Institute Inc., Cary, NC) for multivariate analysis. RESULTS: Twelve patients experienced epileptiform discharges. Risk factors were female sex (odds ratio, 12.60; 95% confidence interval, 1.46-135), delay to the occurrence of beta waves (odds ratio, 0.92; 95% confidence interval, 0.86-0.99), and end-tidal sevoflurane (odds ratio, 8.78; 95% confidence interval, 1.12-69). Epileptiform discharges were not associated with significant hemodynamic or Bispectral Index variations. CONCLUSION: Induction with sevoflurane may result in epileptiform electroencephalographic activity. Only electroencephalographic monitoring allows the diagnosis. Risk factors are mainly female sex, short delay to onset of anesthesia, and high alveolar sevoflurane concentration. Induction with high sevoflurane concentration is controversial mainly in women.

Distressing belching and neuroacanthocytosis.

We report on an uncommon manifestation of molecularly proven neuroacanthocytosis in a 32-year-old man in whom dyspnea with desaturation while awake accompanied by continuous involuntary belching were the major consequences of the disease.

Diffusion-weighted MR imaging with apparent diffusion coefficient and apparent diffusion tensor maps in cervical spondylotic myelopathy.

PURPOSE: To evaluate diffusion-weighted magnetic resonance (MR) imaging in patients with cervical spondylosis and/or myelopathy. MATERIALS AND METHODS: A multishot echo-planar imaging sequence with calculation of apparent diffusion coefficient (ADC) and apparent diffusion tensor (ADT) was applied in 36 patients with symptomatic cervical spondylosis. Diffusion-weighted images read by two neuroradiologists were compared with T2-weighted fast spin-echo images read independently by three neuroradiologists with regard to clinical status (n = 36). MR findings in a selected subgroup of 20 patients whose clinical status was confirmed by electrophysiologic examination also were compared. Sensitivity, specificity, positive predictive value, and negative predictive value of both T2-weighted imaging and diffusion-weighted imaging (ADC and ADT) were calculated and compared. RESULTS: Patients with myelopathy had abnormal ADC (17 of 21) and ADT (15 of 19) maps with increased ADC and ADT values and decreased anisotropy. For the detection of myelopathy, diffusion-weighted ADC maps had a sensitivity of 80% (17 of 21), while T2-weighted images had a sensitivity of 61% (13 of 21). The negative predictive value was 63% (seven of 11) and 60% (12 of 20) for ADC maps and T2-weighted images, respectively. Conversely, the specificity of diffusion-weighted images (53%; seven of 13) was lower than that of T2-weighted images (92%; 12 of 13). In patients with myelopathy confirmed at electrophysiologic examination, the sensitivity of diffusion-weighted images increased to 92% (12 of 13) and the negative predictive value increased to 75% (three of four), while T2-weighted images had a 53% (seven of 13) sensitivity and a 50% (six of 12) negative predictive value. CONCLUSION: Diffusion weighting improved the sensitivity of imaging in cervical spondylotic myelopathy.

Improvement of severe trunk spasms by bilateral high-frequency stimulation of the motor thalamus in a patient with chorea-acanthocytosis.

We report on a patient with a severe form of chorea-acanthocytosis, intractable to medical treatment, who benefited from bilateral high-frequency stimulation (HFS) of the posterior ventral oral nucleus of the thalamus. The frequency of trunk spasms dramatically decreased after surgery and the clinical benefit remained stable 1 year later. However, no clear effect was observed on dysarthria nor on hypotonia, which always impaired gait. We propose that HFS of the motor thalamus is a potential treatment for choreic or truncal dystonic symptoms whenever hypotonia is not the main feature of the syndrome.