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We present a case of dengue with refractory thrombocytopenia who developed cerebral venous thrombosis (CVT) with intraparenchymal hemorrhage warranting surgical decompression. Patient was concluded to have secondary immune thrombocytopenic purpura (ITP) which remained refractory to high dose steroids, IVIg therapy, but responded to thrombopoietin receptor (TPO-R) agonist, eltrombopag. How to cite this article Sharma M, Chandan GS, Arayamparambil PV, Gopalakrishna UK. Case of Near Fatal Massive Intracerebral Bleed Secondary to Cerebral Venous Thrombosis in a Patient with Dengue and Refractory Thrombocytopenia. Indian J Crit Care Med 2020; 24(2):138–140.

H1N1 is seen in tropical countries like India, occurring irrespective of the season. Complications of the disease are frequently encountered and there is little in the way or guidelines as to the how these should be managed. The treatment of one such complication, a recurrent pneumiomediastinum is the subject of the current paper. The management followed guidance for the treatment of a similar condition known as primary spontaneous pneumomediastinum, an uncommon condition resulting from alveolar rupture-otherwise known as the Macklin phenomenon.

Recent studies in animals indicate that even moderate levels of exposure to noise can damage synaptic ribbons between the inner hair cells and auditory nerve fibers without affecting audiometric thresholds, giving rise to the use of the term “hidden hearing loss” (HHL). Given the pervasive exposure to occupational and recreational noise in the general population, it is likely that individuals afflicted with HHL will go unidentified unless sensitive clinical measures are developed to diagnose this condition. To date, the studies employed to characterize HHL in humans have yielded equivocal results - some studies show wave I amplitude decrement while others show no difference in either Wave I amplitude or the sustained phase-locked activity in the frequency following response (FFR). The main objective of this project is to determine stimulus manipulations that produce electrophysiological changes specific to individuals at risk for HHL. The aim is to develop sensitive clinical electrophysiological metrics for early detection of HHL. We reasoned that synaptopathy associated with HHL may be relatively more susceptible to certain stimulus manipulations that affect synaptic level processes, and will likely produce a greater degradation of responses (recorded from the different levels-inner ear, auditory nerve, and brainstem) in individuals at high risk for HHL compared to controls. The specific stimulus manipulations included sound levels, two different adaptation paradigms (stimulus rate neural adaptation and click train (temporal course and recovery from adaptation) paradigm), ABRs and FFRs (speech token) in noise, and changes in rate of frequency sweep (temporal processes involved in representing frequency change). Consistent with previous studies, there were no differences between the low- and high-risk groups in audiometric thresholds or DPOAE amplitude. The high-risk group had significantly lower Wave I amplitude at high sound levels only and across two different adaptation paradigms with little effect on the responses at higher centers reflecting compensatory mechanisms and/or resilience of later waves to stimulus manipulations. The normalized wave I amplitude change with background noise was smaller for the high-risk group suggesting reduced suppressive masking. Despite reduced wave I amplitude for high-risk group; the high-risk group showed no change in rate or click-train induced neural adaptation suggesting that synaptic processes contributing to adaptation remain unaltered; enhanced neural representation of F2 harmonics in quiet as well as background noise; and enhanced representation of rapid tonal sweeps (similar to a dynamic musical note) possibly through corticofugal influence shaped by music experience. These findings suggest that the consequences of music exposure induced synaptopathy reflects a complex interaction of multitude of factors (sound over-exposure, music experience, and homeostatic central compensation. Therefore, there is a need for larger scale datasets with different noise exposure background, longitudinal measurements with an array of behavioral and electrophysiological tests to understand the complex pathogenesis of sound over-exposure damage in normal-hearing individuals.

Objective: The aim of the present study was to examine the effect of degree of temporal processing impairment in adult listeners with ANSD on speech perception measures. Study design: Forty-six listeners with ANSD and 30 normal hearing listeners participated in the study. Temporal resolution was measured using the Temporal Modulation Transfer Function (TMTF). Speech identification scores in quiet were measured for bisyllabic words and Speech Reception Threshold in noise (SRTn) was measured for words. Furthermore, consonant identification was measured for 20 VCV stimuli. Results: Listeners with ANSD performed significantly worse than normal hearing listeners in both temporal resolution and speech perception measures. Peak sensitivity and 3dB cut-off frequency were estimated for each individual in both groups from the TMTFs data using an exponential fitting function. The listeners with ANSD were subgrouped into mild, moderate and severe degrees based on peak sensitivity. As the degree of temporal pr...

Auditory neuropathy spectrum disorder (ANSD) describes a condition in which a patient’s otoacoustic emissions (OAE) are (or were at one time) present and auditory brainstem responses (ABR) are abnormal or absent. ANSD is also diagnosed based on the presence of cochlear microphonics and abnormal or absent ABRs with or without abnormalities of OAE. We noted the changes in audiological characteristics over time with respect to pure tone thresholds, OAEs and Speech Identification Scores (SIS) in seven individuals with ANSD. The results indicated that all the individuals with ANSD had decreased SIS over time, whereas there was subsequent reduction in pure tone thresholds only in nine out of fourteen ears. There was absence of OAEs for two individuals in both ears during the follow-up evaluations. There was no regular pattern of changes in pure tone thresholds or SIS across all individuals. This indicates that there may be gradual worsening of hearing abilities in individuals with ANSD. Thus, regular follow-up and monitoring of audiological changes are necessary for individuals with ANSD. Also, longitudinal studies need to be done to further add evidence to the audiological changes over time in individuals with ANSD.

Objective: The study aimed at exploring the audiological characteristics and the relationship between speech identification scores with cortical evoked potential measures and hearing aid benefit in individuals with auditory neuropathy spectrum disorder (ANSD). Study design: We initiated a retrospective study of patients who were diagnosed as having ANSD. In 198 patients with ANSD, patient history, risk factors, degree and configuration of hearing loss, speech identification scores in quiet and noise, otoacoustic emissions (OAE), immittance evaluation, auditory brainstem responses (ABR), long latency responses (LLR) and hearing aid benefit were assessed. Results: The results showed that the majority of the patients had bilateral ANSD with a female to male ratio of 1.25:1 with the majority having a rising configuration of hearing loss. OAEs were present in most with absent stapedial reflexes and ABR. The study also showed that individuals with ANSD do obtain benefit from hearing aids and it is relat...

BackgroundThe auditory brainstem response (ABR) is usually abnormal in individuals with auditory neuropathy spectrum disorder (ANSD). However, in some such individuals the ABR is preserved at low repetition rates. This study attempts to understand the speech perception abilities of ANSD individuals who have preserved temporal synchronicity.Material and MethodsThere were 149 individuals with ANSD in the study. They were classified into two groups based on preserved or absent ABR. Speech identification scores (SISs) in these individuals in quiet and in the presence of noise were compared.ResultsAt low repetition rates some 12.5% of subjects had preserved ABR with low amplitude wave V. Of these, 81% had an SIS of more than 50% in quiet. However, in patients with absent ABR, only 27% of individuals had an SIS of more than 50%. For subjects who had preserved ABR the mean SIS was 73.1% in quiet and 36.5% in noise compared to 35.9% in quiet and 20.2% in noise for individuals who had absent ABR.ConclusionsOne in eight of the patients with ANSD had preserved ABR. Speech understanding was also better in quiet and in the presence of noise in individuals with preserved ABR. We conclude that speech reception abilities depend upon neural synchronicity at the level of the auditory nerve.

Background: There are many studies reported in the literature that have summarized audiological findings and possible rehabilitation in individuals with auditory neuropathy spectrum disorder (ANSD). However, there are very few studies that have attempted to delineate the gender differences in audiological characteristics and hearing aid benefit in individuals with ANSD. Purpose: The study aimed to explore the differences between males and females in terms of demographic details, audiogram, speech identification scores, otoacoustic emissions, acoustic reflexes, long latency responses, and hearing aid benefit. Research Design: A retrospective study. Study Sample: A total of 255 individuals diagnosed with ANSD were selected for the study. The study included 137 females and 88 males. Data Collection and Analysis: The demographic details, results of diagnostic audiological testing, and hearing aid benefit were analyzed retrospectively. The differences in findings across gender were compared. Results: The study shows that females have a relatively higher degree of hearing loss and that the majority of females show a rising type of audiometric configuration. The study shows that females have poorer speech perception abilities and experience limited benefits from hearing aids compared to males. Conclusions: The results of the study show that there are gender differences in audiological findings and hearing aid benefits in individuals with ANSD. However, well-controlled prospective studies are essential to confirm the results obtained and to identify the possible mechanisms underlying the gender differences.