Objective methods to measure vestibular evoked myogenic potential response saccular tuning curves

Abstract

Objective: To detect cervical vestibular evoked myogenic potential (cVEMP) responses using objective statistical approaches and to apply this approach to estimate saccular frequency-tuning curves in volunteers and Ménière’s disease (MD) patients.

Design: Estimates of cVEMP threshold were carried out by 3 expert raters at 500?Hz and compared to objective threshold estimates (using Hotelling’s T² [HT²] and F_sp). Saccular tuning curves were objectively estimated.

Study sample: Objective and subjective estimates of cVEMP response thresholds were compared for 13 normal hearing adults. Objective measurement of saccular tuning curves was explored in 20 healthy adults and 15 patients with MD.

Results: Significant variability was seen between subjective estimates of cVEMP thresholds. Objective analysis with the HT² test was more sensitive than 2 of 3 experts in detecting responses. The measurement time of cVEMP was considerably reduced with the HT² test. Objective saccular tuning curves in volunteers showed strongest responses at 500?Hz. A flatter tuning curve was seen for MD patients.

Conclusions: There is significant variability in subjective estimations of cVEMP thresholds. Objective analysis methods are more sensitive than subjective analysis, can detect responses rapidly and have potential to reduce variability in threshold estimates, hence they appear well suited to measure cVEMP tuning curves.     

Recurrent giant hemangiomas of liver: Report of two rare cases with literature review

Most hepatic hemangiomas (HHs) are small, asymptomatic and do not require clinical intervention. Surgical resection is only indicated for symptomatic hemangiomas. We report here cases of recurrent HHs in 2 women of 37 and 40 years old, who initially presented with abdominal pain and mass. Radiological examination of each tumor revealed a solitary tumor of 14 and 20 cm in diameter, respectively. Surgical liver segmental resections were performed in both, and the diagnosis of cavernous hemangioma was confirmed. Both patients had recurrent tumor on subsequent radiological examination 4-5 years after the initial surgery. In the first patient, a 15 cm recurrent hemangioma was resected, but multiple hemangiomas were again detected 8 years later occupying the other hepatic lobe, which was not amendable for resection. In the second patient, a 16 cm hemangioma was seen on radiogram, and because the lesion was not symptomatic, conservative observation was offered. Recurrence after liver resection of giant hemangioma is extremely rare. The pathogenesis of tumor progression and recurrence is unknown, as is the management of these patients with recurrent hemangioma, particularly when it is extensive and unresectable.     

Mutation analysis of "Endoglin" and "Activin receptor-like kinase" genes in German patients with hereditary hemorrhagic telangiectasia and the value of rapid genotyping using an allele-specific PCR-technique

Background  

Hereditary hemorrhagic telangiectasia (HHT), also known as Rendu-Osler-Weber syndrome, is an autosomal dominant disorder which is clinically characterised by recurrent epistaxis, mucocutaneous telangiectasia and visceral arteriovenous malformations. Genetic linkage studies identified two genes primarily related to HHT: endoglin (ENG) on chromosome 9q33-34 and activin receptor-like kinase1 (ACVRL1) on chromosome 12q13. We have screened a total of 41 unselected German patients with the suspected diagnosis of HHT. Mutation analysis for the ENG and ACVRL1 genes in all patients was performed by PCR amplification. Sequences were then compared to the HHT database sequences of the ENG mRNA (accession no. BC014271.2) and the ACVRL1 mRNA (accession no. NM000020.1).     

Image-based discriminating morphological features for gastric atrophy assessment: a step to go further

The aim of this study is to establish a basis for automated assessment of gastric atrophy according to the Updated Sydney System. We sought to minimize inter- and intra-observer variations in the application of the Sydney System. A total of 160 biopsies were examined by three pathologists and graded using the visual scale of the Updated Sydney System. A consensus was reached on 135 biopsies. Digital images were captured for the studied biopsies. Image processing techniques were used to extract four morphological features that uniquely discriminate each atrophy grade. The features are related to gland density and shape. To validate the reproducibility of these features, the K-Means clustering technique was used. We were able to grade the atrophy with an overall precision of 95.6%. Furthermore, the proposed features were able to distinguish four discrete grades without any significant overlap. This has not been achieved by previous studies.     

Lack of effectiveness of dexamethasone in neonatal bacterial meningitis

A clinical trial was conducted to determine whether dexamethasone as adjunctive therapy alters the outcome of bacterial meningitis in neonates. Fifty-two full-term neonates with bacterial meningitis were enrolled in a prospective study. Infants were alternately assigned to receive either dexamethasone or not. Twenty-seven received dexamethasone in addition to standard antibiotic treatment and 25 received antibiotics alone. Dexamethasone therapy was started 10–15 min before the first dose of antibiotics in a dose of 0.15 mg/kg per 6 h for 4 days. Baseline characteristics, clinical and laboratory features in the two groups were virtually similar. Both groups showed a similar clinical response and similar frequency of mortality and sequelae. Six (22%) babies in the treatment group died compared to 7 (28%) in the control group (P = 0.87). At follow up examinations up to the age of 2 years, 6 (30%) of dexamethasone recipients and 7 (39%) of the control group had mild or moderate/severe neurological sequelae. Audiological sequelae were seen in two neonates in the dexamethasone group compared to one in the control group. Conclusion Adjunctive dexamethasone therapy does not improve the outcome of neonatal bacterial meningitis. Received: 22 December 1997 / Accepted: 14 March 1998