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Purpose: The objective of this study was to determine the normative vestibulo- ocular reflex gain output values of the computerized rotational head impulse test (crHIT) with stationary visual targets (earth bound) in healthy participants in each decade age band of life: 10-19, 20-29, 30-39, 40-49, 50-59, 60-69, and 70+ years. Method: Seventy-seven community-dwelling participants (10-85 years of age) with normal lateral semicircular canal (SCC) functioning and no symptoms or history of vestibular dysfunction were recruited through convenience sampling and assessed with the crHIT using stationary targets. These participants were assessed using two standard protocols in a randomized order. Results: Results from 77 participants (Mage = 46 years; 43 women, 34 men) were analyzed. Pearson's correlation coefficient and simple linear regression indicated a statistically significant relationship between crHIT gain output and age (p >.05) for right gain, 1030°/s², and left gain, 1005°/s². Although a statistically significant relationship was found, the slope was minor, demonstrating that the clinical effect of age on crHIT gain output was insignificant. Furthermore, no statistically significant relationship exists between crHIT gain output and gender (p > .05). Age-dependent normative data were calculated using the 2.5th and 97.5th confidence interval (CI) percentile method. The responses of angular vestibulo-ocular reflex (aVOR) gain values for crHIT are expected to occur within the range for lower limit reference interval (RI) of 0.85-0.9 and upper limit RI of 1.11-1.18 for 1030°/s² and lower limit RI of 0.86-0.92 and upper limit RI of 1.13-1.16 for 1005°/s² .It can be expected that 90% CI of the population with normal lateral SCC function- ing will have aVOR gain values that fall within this range. Conclusion: Despite a statistically significant relationship that exists with aVOR gain output and age, the changes are minor, declining by 0.0088 units per 10 years, justifying the same normative data for all decade age bands. [ABSTRACT FROM AUTHOR]

To compare the response rate and response parameters of cervical and ocular vestibular evoked myogenic potentials (c&oVEMP) elicited by narrowband (NB) and broadband (BB) CE-Chirp, with the more classical tone burst (TB) and click VEMPs. The response rate, latency, amplitude and asymmetry ratio of c&oVEMPs elicited by 95 dB nHL air conducted (AC) 500 Hz NB CE-chirp, BB CE-chirp, 500 Hz TB and click stimuli were recorded bilaterally. 20 male and 38 female participants (19–39 years). For the cVEMP, the highest response rate was found for NB chirp (100%), followed by TB (91%), BB chirp (87%) and finally click (85%). A similar order was seen for oVEMP with percentages of 100%; 57%, 57%, and 43%. The 500 Hz NB CE-Chirp elicited significantly shorter cVEMP P1 and N1 latencies and significantly larger c&oVEMP amplitudes compared to all other stimuli. BB CE-Chirp elicited significantly shorter c&oVEMP P1 and N1 latencies with smaller amplitudes compared to TB. Asymmetry ratios were not statistically significant for all comparisons. The 500 Hz NB CE-chirp provides the highest response rates, shorter latencies and larger amplitudes, and therefore seem a promising stimulus for reliably measuring c&oVEMPs in clinical practice. [ABSTRACT FROM AUTHOR]

Abstract Background The analysis of complex cytogenetic databases of distinct leukaemia entities may help to detect rare recurring chromosome aberrations, minimal common regions of gains and losses, and also hot spots of genomic rearrangements. The patterns of the karyotype alterations may provide insights into the genetic pathways of disease progression. Results We developed a simplified computer readable cytogenetic notation (SCCN) by which chromosome findings are normalised at a resolution of 400 bands. Lost or gained chromosomes or chromosome segments are specified in detail, and ranges of chromosome breakpoint assignments are recorded. Software modules were written to summarise the recorded chromosome changes with regard to the respective chromosome involvement. To assess the degree of karyotype alterations the ploidy levels and numbers of numerical and structural changes were recorded separately, and summarised in a complex karyotype aberration score (CKAS). The SCCN and CKAS were used to analyse the extend and the spectrum of additional chromosome aberrations in 94 patients with Philadelphia chromosome positive (Ph-positive) acute lymphoblastic leukemia (ALL) and secondary chromosome anomalies. Dosage changes of chromosomal material represented 92.1% of all additional events. Recurring regions of chromosome losses were identified. Structural rearrangements affecting (peri)centromeric chromosome regions were recorded in 24.6% of the cases. Conclusions SCCN and CKAS provide unifying elements between karyotypes and computer processable data formats. They proved to be useful in the investigation of additional chromosome aberrations in Ph-positive ALL, and may represent a step towards full automation of the analysis of large and complex karyotype databases.

Objective: A systematic literature review and meta-analysis was performed to determine the effect of stimulus type, SCM muscle activation method, transducer type, and method to control SCM muscle EMG level on response parameter values for 0.1-ms click-evoked and 500-Hz tone burst cVEMPs. A description of normative response values was attempted. Design: An electronic systematic literature review was performed to obtain normative cVEMP response data. Subsequently a meta-analysis was conducted to determine significant effects on cVEMP response parameters and to obtain norms. Study sample: Scopus was used to identify reports containing normative data. Reports were selected based on inclusion and exclusion criteria determined beforehand. Weighted means were calculated and compared to identify significant effects and normative data. Results: Sixty-six reports were included in the systematic review. Stimulus type, SCM muscle activation method, transducer type, and method to control SCM muscle EMG level had significant effects on all response parameters. Conclusions: Optimal stimulus and recording parameters suggested by previous research are confirmed by the current systematic review and meta-analysis and are suggested for clinical use. Response parameter values are influenced by variations in stimulus and recording parameters and normative response values are suggested as guideline for cVEMP interpretation. [ABSTRACT FROM AUTHOR]

Objectives: This study describes the prevalence and nature of auditory and otological manifestations in adults with HIV/AIDS through clinical examinations and self-reported symptoms across stages of disease progression. Design: Descriptive cross-sectional group design. Study sample: Two hundred HIV positive adult patients (56.5% male; 43.5% female; mean age: 37.99 ± 6.66 years) attending the Infectious Disease Clinic of a tertiary referral hospital in Pretoria, South Africa were included. Patients were interviewed, medical files were reviewed, and clinical examinations, including otoscopy, tympanometry, pure-tone audiometry, and distortion product otoacoustic emissions, were conducted. A matched HIV negative control group was used to compare hearing loss prevalence. Results: Tinnitus (26%), vertigo (25%) hearing loss (27.5%), otalgia (19%), and ear canal pruritis (38%) were prevalent self-reported symptoms. Abnormalities in otoscopy, tympanometry, and otoacoustic emissions were evident in 55%, 41%, and 44% of patients respectively. Pure-tone average (PTA) hearing loss > 25 dBHL was evident in 14% of patients and 39% for hearing loss > 15 dBHL (PTA). Significant differences across average thresholds in the HIV positive and HIV negative control group was present. An increase in self reported vertigo, self reported hearing loss, OAE abnormalities, and hearing loss (PTA > 15 dBHL and PTA > 25 dBHL) was seen with disease progression but was not statistically significant. A significant increase (p <.05) in sensorineural hearing loss was however evident with disease progression. Conclusions: Auditory and otological symptoms are more common in patients with HIV with a general increase of symptoms, especially sensorineural hearing loss, towards advanced stages of disease progression. [ABSTRACT FROM AUTHOR]

Unregulated proliferation of mainly myeloid bone marrow cells and genetic changes in the hematopoietic stem cell system are important features in Chronic Myeloid Leukemia (CML). In clinical diagnosis of CML, classical banding techniques, fluorescence in situ hybridization (FISH) probing for the Philadelphia chromosome (Ph) or polymerase chain reaction amplifying the fusion products of the BCR-ABL fusion are state of the art techniques. Nevertheless, the genome of CML patients harbors many more cytogenetic changes. These might be hidden in subpopulations due to clonal events or involved in extremely complex aberrations. To identify these additional changes, several cytogenetic and molecular genetic techniques could be applied. Nevertheless, it has been proposed that identifying these aberrations is time consuming and costly and since they cannot be converted into a benefit for the patients, the necessity to perform these investigations has been questioned. In the times where highly specialized medicine is advancing into several areas of cancer, this attitude needs to be reassessed. Therefore, we looked at the usefulness of a combination of different techniques to unravel the genetic changes in CML patients and to identify new chromosomal aberrations, which potentially can be correlated to different stages of the disease and the strength of therapy resistance. We are convinced that the combination of these techniques could be extremely useful in unraveling even the most complex karyotypes and in dissecting different clones contributing to the disease. We propose that by doing so, this would improve CML diagnostic and prognostic findings, especially with regard to CML resistance mechanisms and new therapeutic strategies.