Ingrida Ulozienė

Reliability and validity of the Lithuanian Tinnitus Handicap Inventory

OBJECTIVE The aim of this study was to determine the reliability and validity of the Lithuanian version of the Tinnitus Handicap Inventory (THI), a self-report measure of perceived tinnitus handicap. MATERIALS AND METHODS A cross-sectional psychometric validation study was performed in the University Hospital. A total of 248 subjects reporting chronic tinnitus as their primary complaint or secondary to hearing loss were encluded in the study and filled in the Lithuanian version of THI. For assessment of construct validity a subgroup of 55 participants completed the Lithuanian version of the Hospital Anxiety and Depression Scale as a measure of self-perceived levels of anxiety and depression. Test-retest and internal consistency reliability as well as construct validity were calculated. RESULTS The Lithuanian version of the THI and its subscales showed a robust internal consistency reliability (Cronbachs alpha=0.93) comparable to the original version. Statistically significant correlations were observed between the Lithuanian translation of the THI and the measures of self-perceived levels of anxiety and depression using HADS. Confirmatory factor analysis demonstrated that the three subscales of the THI Lithuanian version corresponded to three different factors, which strongly correlated between themselves. CONCLUSIONS The results suggest that the Lithuanian version of THI maintains its original validity and may serve as reliable and valid measure of general tinnitus related distress that can be used in a clinical setting to quantify the impact of tinnitus on daily living.

Associations of HLA DRB1 alleles with IgG oligoclonal bands and their influence on multiple sclerosis course and disability status

BACKGROUND AND AIM Oligoclonal bands (OCB) may be associated with the genes of HLA complex, which allows to consider the possible interaction of genetic and immunological factors and its importance in the development and progression of multiple sclerosis (MS). The aim of this study was to evaluate the associations between HLA DRB1 alleles and oligoclonal bands (OCBs) in the disease course and disability of multiple sclerosis (MS) patients. MATERIALS AND METHODS This was a prospective study of 120 patients with MS. HLA DRB1 alleles were genotyped using the polymerase chain reaction. Matched cerebrospinal fluid (CSF) and plasma samples were analyzed using isoelectric focusing and IgG specific immunofixation to test for the presence of intrathecal specific OCB. RESULTS HLA DRB1*08 allele was related to a lower degree of disability. Oligoclonal bands were an independent and significant factor that influenced disability status irrespective of HLA DRB1* 04, *07, *08, *13, *15 and *16 alleles. Age at the onset and duration of the disease were independent and significant factors for MS progression in all logistic regression models with each newly added HLA DRB1 allele. HLA DRB1*08 allele was related to 75% lower odds that relapsing remitting (RR) MS will change to a progressive course MS irrespective of the other factors investigated. Detection of OCBs in the CSF was associated with the higher possibility of RR MS progression in all cases, except when the *08 allele was present. CONCLUSIONS OCBs had an influence on disability status, while HLA DRB1*08 allele was significantly associated with lower possibility that RR MS will change to progressive course MS.

Virtual Reality Based System for Investigation of Peripheral Vestibular Function

A prototype of virtual reality based system for investigation of peripheral vestibular function was presented. The system uses low cost head-mounted display (HMD) Oculus Rift 1 with built-in head orientation tracker and custom developed software. There were two virtual reality based tests implemented for investigation of peripheral vestibular function: subjective visual vertical and head tilt. HMD allowed to extend the tests by inclusion of dynamic 3D type disturbances. 38 normal subjects participated in the pilot study and were screened by using the proposed and reference methods. The experimental results suggest that virtual reality system Oculus Rift is able to generate the required visual stimuli and measure orientation parameters during subjective vertical tests. The research should be extended by inclusion of subjects with vestibular dysfunction.

Effect of Laryngeal Squamous Cell Carcinoma Tissue Implantation on the Chick Embryo Chorioallantoic Membrane: Morphometric Measurements and Vascularity

Background. The aim of this study was to develop chick embryo chorioallantoic membrane (CAM) model of laryngeal squamous cell carcinoma (LSCC) and to evaluate the morphological and morphometric characteristics and angiogenic features of it. Methods. Fresh LSCC tissue samples obtained from 6 patients were implanted onto 15 chick embryo CAMs. Morphological, morphometric, and angiogenic changes in the CAM and chorionic epithelium were evaluated up to 4 days after the tumor implantation. Immunohistochemical analysis (34βE12, CD31, and Ki67 staining) was performed to detect cytokeratins and tumor endothelial cells and to evaluate the proliferative capacity of the tumor before and after implantation on the CAM. Results. The implanted LSCC tissue samples survived on the CAM in all the experiments and retained the essential morphologic characteristics and proliferative capacity of the original tumor. Implants induced thickening of both the CAM (103–417%, p = 0.0001) and the chorionic epithelium (70–140%, p = 0.0001) and increase in number of blood vessels (75–148%, p = 0.0001) in the CAM. Conclusions. This study clarifies that chick embryo CAM is a relevant assay for implanting LSCC tissue and provides the first morphological and morphometric characterization of the LSCC CAM model that opens new perspectives to study this disease.