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  • Management of benign middle ear tumors: A series of 7 cases. Ear, nose, & throat journal Qian, Z. J., Coffey, A. M., O'Toole, K. M., Lalwani, A. K. ; 96 (10-11): 426?32

    Abstract

    Benign middle ear tumors represent a rare group of neoplasms that vary widely in their pathology, anatomy, and clinical findings. These factors have made it difficult to establish guidelines for the resection of such tumors. Here we present 7 unique cases of these rare and diverse tumors and draw from our experience to recommend optimal surgical management. Based on our experience, a postauricular incision is necessary in nearly all cases. Mastoidectomy is required for tumors that extend into the mastoid cavity. Whenever exposure or hemostasis is believed to be inadequate with simple mastoidectomy, canal-wall-down mastoidectomy should be performed. Finally, disarticulation of the ossicular chain greatly facilitates tumor excision and should be performed early in the procedure.

    View details for PubMedID 29121375

  • Association of Cardiovascular Comorbidities With Hearing Loss in the Older Old. JAMA otolaryngology-- head & neck surgery Wattamwar, K., Qian, Z. J., Otter, J., Leskowitz, M. J., Caruana, F. F., Siedlecki, B., Spitzer, J. B., Lalwani, A. K. 2018

    Abstract

    In the United States, the population of individuals older than 80 years is expected to double in the next 40 years. Cardiovascular comorbidities are prevalent in this older old population, and their relationship with hearing loss has not been well characterized.To investigate the association of cardiovascular disease (CVD)-related risk factors with auditory function among the older old (>80 years).Audiological data and medical records from 2001 through 2014 of 433 patients aged 80 to 106 years at an academic medical center were analyzed in 2017.The degree of low- and high-frequency hearing loss of participants with coronary artery disease, diabetes, hypertension, history of cerebrovascular accident, and smoking status was compared with that of disease-free individuals. Rate of hearing loss was also determined.Among the 433 patients (67% female; mean [SD] age, 89 [5.8] years), the presence of at least 1 cardiovascular morbidity was associated with elevated mean (SD) low-frequency pure-tone average (LFPTA) of 42.4 (1.6) vs 36.9 (3.5) decibels hearing loss (dB HL), a difference of 5.47 (95% CI, 4.15-9.49) dB HL. Among the 96 patients with 2 audiograms performed at age 80 years or older from which the rate of hearing loss could be calculated, 32 patients had CVD or related risk factors and 64 were healthy controls. Those with at least 1 disease had accelerated hearing loss. Patients with cardiovascular morbidity experienced a faster mean (SD) decline in LFPTA of 1.90 (0.27) vs 1.18 (0.42) dB HL/y, a difference of 0.72 (95% CI, 0.08-1.36) dB HL/y. Of the conditions studied, coronary artery disease had the highest association with audiometric thresholds and was associated with hearing loss at all frequencies tested and with poor word recognition score. Hearing loss was more strongly associated with CVD risk factors in men than in women.In this study of the older old, cardiovascular risk factors and disease were associated with worse hearing and a greater rate of hearing deterioration. Hearing loss in women was less associated with the presence of CVD, possibly owing to the cardioprotective effects of estrogen. The association of hearing with CVD severity and management remains to be determined.

    View details for DOI 10.1001/jamaoto.2018.0643

    View details for PubMedID 29902313

  • Increases in the Rate of Age-Related Hearing Loss in the Older Old JAMA OTOLARYNGOLOGY-HEAD & NECK SURGERY Wattamwar, K., Qian, Z. J., Otter, J., Leskowitz, M. J., Caruana, F. F., Siedlecki, B., Spitzer, J. B., Lalwani, A. K. 2017; 143 (1): 41-45

    Abstract

    There is a critical disparity in knowledge regarding the rate and nature of hearing loss in the older old (80 years and older).To determine if the rate of age-related hearing loss is constant in the older old.We performed a retrospective review that began on August 1, 2014, with audiometric evaluations at an academic medical center of 647 patients aged between 80 and 106 years, of whom 141 had multiple audiograms.From a population perspective, the degree of hearing loss was compared across the following age brackets: 80 to 84 years, 85 to 89 years, 90 to 94 years, and 95 years and older. From an individual perspective, the rate of hearing decrease between 2 audiograms was compared with age.Changes in hearing among age brackets were higher during the 10th decade of life than the 9th decade at all frequencies (5.4-11.9 dB hearing level [dB HL]) for the 647 patients (mean [SD] age, 90 [5.5] years). Correspondingly, the annual rate of low-frequency hearing loss was faster during the 10th decade by the 3.8 dB HL per year at 0.25 kHz, 3.8 dB HL per year at 0.5 kHz, and 3.2 dB HL per year at 1 kHz. Despite the universal presence of hearing loss in our sample, 382 patients (59%) used hearing aids.There is a significant increase in the rate of hearing loss in patients during the 10th decade of life compared with the 9th decade that represents a fundamental change in the mechanistic process of presbycusis. Despite the potential benefit of hearing aids, they remain underused in the older old. Use may be improved by changing the method of hearing rehabilitation counseling from a patient-initiated model to a chronic disease example.

    View details for DOI 10.1001/jamaoto.2016.2661

    View details for Web of Science ID 000394441000007

    View details for PubMedID 27632707

  • A novel method of quantifying brain atrophy associated with age-related hearing loss. NeuroImage. Clinical Qian, Z. J., Chang, P. D., Moonis, G., Lalwani, A. K. 2017; 16: 205?9

    Abstract

    A growing body of evidence has shown that a relationship between age-related hearing loss and structural brain changes exists. However, a method to measure brain atrophy associated with hearing loss from a single MRI study (i.e. without an interval study) that produces an independently interpretable output does not. Such a method would be beneficial for studying patterns of structural brain changes on a large scale. Here, we introduce our method for this. Audiometric evaluations and mini-mental state exams were obtained in 34 subjects over the age of 80 who have had brain MRIs in the past 6 years. CSF and parenchymal brain volumes (whole brain and by lobe) were obtained through a novel, fully automated algorithm. Atrophy was calculated by taking the ratio of CSF to parenchyma. High frequency hearing loss was associated with disproportional temporal lobe atrophy relative to whole brain atrophy independent of age (r = 0.471, p = 0.005). Mental state was associated with frontoparietal atrophy but not to temporal lobe atrophy, which is consistent with known results. Our method demonstrates that hearing loss is associated with temporal lobe atrophy and generalized whole brain atrophy. Our algorithm is efficient, fully automated, and able to detect significant associations in a small cohort.

    View details for DOI 10.1016/j.nicl.2017.07.021

    View details for PubMedID 28808617

    View details for PubMedCentralID PMC5544491

  • Prophages mediate defense against phage infection through diverse mechanisms ISME JOURNAL Bondy-Denomy, J., Qian, J., Westra, E. R., Buckling, A., Guttman, D. S., Davidson, A. R., Maxwell, K. L. 2016; 10 (12): 2854-2866

    Abstract

    The activity of bacteriophages poses a major threat to bacterial survival. Upon infection, a temperate phage can either kill the host cell or be maintained as a prophage. In this state, the bacteria carrying the prophage is at risk of superinfection, where another phage injects its genetic material and competes for host cell resources. To avoid this, many phages have evolved mechanisms that alter the bacteria and make it resistant to phage superinfection. The mechanisms underlying these phentoypic conversions and the fitness consequences for the host are poorly understood, and systematic studies of superinfection exclusion mechanisms are lacking. In this study, we examined a wide range of Pseudomonas aeruginosa phages and found that they mediate superinfection exclusion through a variety of mechanisms, some of which affected the type IV pilus and O-antigen, and others that functioned inside the cell. The strongest resistance mechanism was a surface modification that we showed is cost-free for the bacterial host in a natural soil environment and in a Caenorhabditis. elegans infection model. This study represents the first systematic approach to address how a population of prophages influences phage resistance and bacterial behavior in P. aeruginosa.

    View details for DOI 10.1038/ismej.2016.79

    View details for Web of Science ID 000394508000008

    View details for PubMedID 27258950

    View details for PubMedCentralID PMC5148200

  • Hearing Aid Use is Associated with Better Mini-Mental State Exam Performance. American journal of geriatric psychiatry Qian, Z. J., Wattamwar, K., Caruana, F. F., Otter, J., Leskowitz, M. J., Siedlecki, B., Spitzer, J. B., Lalwani, A. K. 2016; 24 (9): 694-702

    Abstract

    Hearing loss is associated with cognitive decline in the elderly. However, it is unknown if the use of hearing aids (HAs) is associated with enhanced cognitive function.In a cross-sectional study at an academic medical center, participants underwent audiometric evaluation, the Mini-Mental State Exam (MMSE), and the Trail Making Test, Part B (TMT-B). The impact of use versus disuse of HAs was assessed. Performance on cognitive tests was then compared with unaided hearing levels.HA users performed better on the MMSE (1.9 points; rank-sum, p?=?0.008) despite having worse hearing at both high frequencies (15.3-dB hearing level; t test, p?

    View details for DOI 10.1016/j.jagp.2016.03.005

    View details for PubMedID 27394684

  • Asymmetric Hearing Loss Is Common and Benign in Patients Aged 95 Years and Older LARYNGOSCOPE Leskowitz, M. J., Caruana, F. F., Siedlecki, B., Qian, Z. J., Spitzer, J. B., Lalwani, A. K. 2016; 126 (7): 1630-1632

    Abstract

    The objective of our study was to investigate age-specific auditory function in the patient population aged 95 years and older.Retrospective chart review at a tertiary medical center.Medical records of 51 patients older than 95 years (82% female, 18% male) who underwent audiologic testing were reviewed. The following information was collected: age at time of most recent audiogram and prior audiograms; results of pure tone, immittance, and speech audiometry; and findings on radiologic imaging.None of the subjects had hearing in the normal range. For the poorer hearing ear, average low-frequency, high-frequency, and overall pure tone averages (PTA) for the population were 67.9, 82.1, and 74.9 dB hearing level, respectively. Mean word recognition score (WRS) was 57.6% and deteriorated with increasing PTA (P?=?.0002). Asymmetry, defined by a 10-dB difference at two frequencies, was present in 39.2% of the sample, and WRS asymmetry, defined as a difference of 12% in WRS between ears, was present in 33.0% of the sample. Retrocochlear evaluation did not identify pathology in any of the cases tested. In the poorer hearing ear, average decline in PTA per year was 2.9 dB.In individuals >95 years of age, hearing loss was universal, moderately severe to profound in magnitude, and associated with substantial loss of speech recognition. Hearing loss progresses at a rate greater than for younger cohorts. In this "oldest old" population, asymmetry of loss and WRS was common and is not indicative of retrocochlear pathology.4 Laryngoscope, 126:1630-1632, 2016.

    View details for DOI 10.1002/lary.25503

    View details for Web of Science ID 000379983800032

    View details for PubMedID 27040356

  • Microperforations Significantly Enhance Diffusion Across Round Window Membrane OTOLOGY & NEUROTOLOGY Kelso, C. M., Watanabe, H., Wazen, J. M., Bucher, T., Qian, Z. J., Olson, E. S., Kysar, J. W., Lalwani, A. K. 2015; 36 (4): 694-700

    Abstract

    Introduction of microperforations in round window membrane (RWM) will allow reliable and predictable intracochlear delivery of pharmaceutical, molecular, or cellular therapeutic agents.Reliable delivery of medications into the inner ear remains a formidable challenge. The RWM is an attractive target for intracochlear delivery. However, simple diffusion across intact RWM is limited by what material can be delivered, size of material to be delivered, difficulty with precise dosing, timing, and precision of delivery over time. Further, absence of reliable methods for measuring diffusion across RWM in vitro is a significant experimental impediment.A novel model for measuring diffusion across guinea pig RWM, with and without microperforation, was developed and tested: cochleae, sparing the RWM, were embedded in 3D-printed acrylic holders using hybrid dental composite and light cured to adapt the round window niche to 3 ml Franz diffusion cells. Perforations were created with 12.5-?m-diameter needles and examined with light microscopy. Diffusion of 1 mM Rhodamine B across RWM in static diffusion cells was measured via fluorescence microscopy.The diffusion cell apparatus provided reliable and replicable measurements of diffusion across RWM. The permeability of Rhodamine B across intact RWM was 5.1 × 10(9-) m/s. Manual application of microperforation with a 12.5-?m-diameter tip produced an elliptical tear removing 0.22 ± 0.07% of the membrane and was associated with a 35× enhancement in diffusion (P < 0.05).Diffusion cells can be applied to the study of RWM permeability in vitro. Microperforation in RWM is an effective means of increasing diffusion across the RWM.

    View details for Web of Science ID 000351000600021

    View details for PubMedID 25310125

    View details for PubMedCentralID PMC4359065

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