The effect of flumazenil on subclinical psychometric or neurophysiological alterations in cirrhotic patients: a double-blind placebo-controlled study.

It is not yet clear if benzodiazepine receptor ligands, implicated in the pathophysiology of hepatic coma, also have a role in subclinical cognitive or neurophysiological alterations in cirrhotic patients. Therefore, we carried out a double-blind, placebo-controlled study to evaluate the effectiveness of flumazenil, a benzodiazepine antagonist, on brainstem auditory evoked responses and on the number connection test in cirrhotic patients with subclinical neurophysiological or cognitive alterations. Thirteen cirrhotic subjects with subclinical neurophysiological or cognitive alterations were studied. A total of 3 mg of flumazenil or saline was infused intravenously. Before and after the infusion, the number connection test was administered and brainstem auditory evoked responses recorded. After 72 h, patients were crossed over. Flumazenil did not influence brainstem auditory evoked responses or the number connection test. A screening test for benzodiazepines was negative in all subjects. We conclude that benzodiazepine receptor ligands have a negligible role, if any, in the pathophysiology of subclinical neurophysiological or cognitive alterations of cirrhotic patients.

Menière's disease in congenital nephrogenic diabetes insipidus: report of two twins.

Two cases, twins, affected by congenital nephrogenic diabetes insipidus (CNDI) with a high daily volume of dilute urine excretion and periods of compensatory high levels of antidiuretic hormone (ADH) simultaneously developed a fluctuating Menière-type hearing loss. It is well known that the kidney and the cochlea are linked by structural and anatomic characteristics, as well as by the physiologic mechanism of electrolytes and fluid regulation. The patients herein described seem to be paradoxical, because they suffered from hydropic hearing loss despite the pathophysiologic mechanism of CNDI and the possible role played by ADH in water regulation in the inner ear. The consequences on Menière's disease of the different therapeutic regimens followed by the two CNDI patients are discussed. To our knowledge these are the first cases of CNDI with Menière's disease described in the literature.

[Spontaneous reparation of post-traumatic tympanic perforation: an experimental study in rats]. / Riparazione spontanea della perforazione timpanica post-traumatica: studio sperimentale nel ratto.

In most patients tympanic membrane perforation spontaneously repairs itself. Nonetheless, in several cases the perforation persists due either to traumatic or phlogistic damage. Although the membrane perforation healing process has been under study for over a century there are still two contrasting theories. One of these theories asserts that repair takes place through the growth of granulation tissue while the other believes that epithelial migration is at the basis of healing. In the present study an experimental animal model (rat) was used in order to assess the staging of the natural evolution of post-traumatic membrane perforation and to characterize, from a morphological and sub-microscopic point of view, the cellular population and microstructural aspects of the extracellular matrix. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were employed to evaluate the progress in tympanic membrane healing and to make a comparison with the most recent theories. Eighteen Sprague-Dawley rats weighing 230-260 gr of the same age (10 weeks) were used in the study. The animals were anesthetized by intraperitoneal injections of Na-pentobarbital (NembutalR) (45 mg/Kg) and, under operating microscope, bilateral perforation of the upper rear quadrant of the pars tensa was performed with a myringotomy lancet. The animals were subjected to periodic follow-ups over next 30 days. Three animals were sacrificed during each control and the tympanic membrane was removed for TEM and SEM study. On the basis of the present study the following conclusions can be drawn: a) primary healing of the lesion is through granulation tissue; b) the healed T.M. is composed of three normal layers as is the normal T.M.; c) the presence of fibroblasts in the intermediate neoformed fibrous layer leads one to conclude that its extracellular matrix is produced and organized "in situ"; d) the neoformed lamina propria has a disorganized, fibrous structure.

Auditory and academic performance of children with unilateral hearing loss.

Since the data provided in the literature concerning unilateral hearing loss in children are still lacking, we decided to study a group of subjects suffering from unilateral sensorineural deafness that has developed during the first 12 years of life. One hundred and fifteen subjects out of 150 answered a questionnaire that intended to investigate at what age the disorder developed, how it was recognized, its possible causes and a subjective evaluation of the difficulties encountered because of the hearing deficiency. In a second stage of the research, more detailed case history data were obtained on 30 children who satisfied more stringent selection criteria. The same children were compared with a matched control group of 30 normal hearing subjects, on speech in noise recognition, and sound localization skills. Results were correlated with the academic and educational progress and case history data. Our results may demonstrate that unilateral deafness represents a far from negligible handicap concerning the child's learning and relationship with classmates and teachers, specially during compulsory school life.