Previous studies have shown that residual acoustic hearing supplements cochlear implant function to improve speech recognition in noise as well as perception of music. The current study had two primary objectives. First, we sought to determine how cochlear implantation and electrical stimulation over a time period of 14 to 21 months influence cochlear structures such as hair cells and spiral ganglion neurons. Second, we sought to investigate whether the structures that provide acoustic hearing also affect the perception of electrical stimulation. We compared psychophysical responses to cochlear implant stimulation in two groups of adult guinea pigs. Group I (11 animals) received a cochlear implant in a previously untreated ear, while group II (ten animals) received a cochlear implant in an ear that had been previously infused with neomycin to destroy hearing. Psychophysical thresholds were measured in response to pulse-train and sinusoidal stimuli. Histological analysis of all group I animals and a subset of group II animals was performed. Nine of the 11 group I animals showed survival of the organ of Corti and spiral ganglion neurons adjacent to the electrode array. All group I animals showed survival of these elements in regions apical to the electrode array. Group II animals that were examined histologically showed complete loss of the organ of Corti in regions adjacent and apical to the electrode array and severe spiral ganglion neuron loss, consistent with previous reports for neomycin-treated ears. Behaviorally, group II animals had significantly lower thresholds than group I animals in response to 100 Hz sinusoidal stimuli. However, group I animals had significantly lower thresholds than group II animals in response to pulse-train stimuli (0.02 ms/phase; 156 to 5,000 pps). Additionally, the two groups showed distinct threshold versus pulse rate functions. We hypothesize that the differences in detection thresholds between groups are caused by the electrical activation of the hair cells in group I animals and/or differences between groups in the condition of the spiral ganglion neurons.
BACKGROUND Exome and targeted sequencing studies have identified potential driver mutations for a variety of tumor types. Cutaneous squamous cell carcinoma (cSCC) is one of the most highly mutated cancers but is typically associated with low rates of metastasis and high survival rates. Nevertheless, metastatic cSCC is a significant health threat; up to 8800 individuals die yearly from this disease. METHODS As it is difficult to predict which cSCCs are more likely to metastasize, and because there are no targeted therapies specifically designated for metastatic cSCC, we performed exome and/or targeted sequencing of 18 metastatic and 10 primary cSCCs to identify mutations that were more frequent in metastatic tumors and might be targeted for therapeutic benefit. We compared our results to published sequencing results of an additional 223 primary tumors and 68 metastatic cSCCs. RESULTS We identified genes showing higher mutation frequencies in metastatic cSCC relative to primary tumors including the chromatin remodeling gene KMT2D and the classic skin tumor suppressor TP53 which was mutated in 54% of primary tumors relative to 85% of metastatic tumors (p <0.0001). CONCLUSIONS These studies uncover potential pathways important in metastatic cSCC that broaden our understanding of the biology contributing to aggressive tumor behavior and may lead to new therapeutic strategies.
Background The COVID-19 pandemic has required triage and delays in surgical care throughout the world. The impact of these surgical delays on survival for patients with head and neck squamous cell carcinoma (HNSCC) remains unknown. Methods A retrospective cohort study of 37 730 patients in the National Cancer Database with HNSCC who underwent primary surgical management from 2004 to 2016 was performed. Uni- and multivariate analyses were used to identify predictors of overall survival. Bootstrapping methods were used to identify optimal time-to-surgery (TTS) thresholds at which overall survival differences were greatest. Cox proportional hazard models with or without restricted cubic splines were used to determine the association between TTS and survival. Results The study identified TTS as an independent predictor of overall survival (OS). Bootstrapping the data to dichotomize the cohort identified the largest rise in hazard ratio (HR) at day 67, which was used as the optimal TTS cut-point in survival analysis. The patients who underwent surgical treatment longer than 67 days after diagnosis had a significantly increased risk of death (HR, 1.189; 95% confidence interval [CI], 1.122–1.261; P < 0.0001). For every 30-day delay in TTS, the hazard of death increased by 4.6%. Subsite analysis showed that the oropharynx subsite was most affected by surgical delays, followed by the oral cavity. Conclusions Increasing TTS is an independent predictor of survival for patients with HNSCC and should be performed within 67 days after diagnosis to achieve optimal survival outcomes. Electronic supplementary material The online version of this article (10.1245/s10434-020-09326-4) contains supplementary material, which is available to authorized users.
Perception of electrical stimuli varies widely across users of cochlear implants and across stimulation sites in individual users. It is commonly assumed that the ability of subjects to detect and discriminate electrical signals is dependent, in part, on conditions in the implanted cochlea, but evidence supporting that hypothesis is sparse. The objective of this study was to define specific relationships between the survival of tissues near the implanted electrodes and the functional responses to electrical stimulation of those electrodes. Psychophysical and neurophysiological procedures were used to assess stimulus detection as a function of pulse rate under the various degrees of cochlear pathology. Cochlear morphology, assessed post-mortem, ranged from near-normal numbers of hair cells, peripheral processes and spiral ganglion cells, to complete absence of hair cells and peripheral processes and small numbers of surviving spiral ganglion cells. The psychophysical and neurophysiological studies indicated that slopes and levels of the threshold versus pulse rate functions reflected multipulse integration throughout the 200 ms pulse train with an additional contribution of interactions between adjacent pulses at high pulse rates. The amount of multipulse integration was correlated with the health of the implanted cochlea with implications for perception of more complex prosthetic stimuli.
Objective To (1) determine the overall complication rate, wound healing, and wound infection complications and (2) identify preoperative, intraoperative, and postoperative predictors of these complications. Study Design Case series with chart review. Setting Tertiary academic cancer hospital. Subjects and Methods All head and neck free flap patients at The Ohio State University (2006-2012) were assessed. Multivariable logistic regression assessed the impact of patient factors, flap and wound factors, and intraoperative factors on the aforementioned quality metric outcomes. Results Of the 515 patients identified, 54% had a complication predicted by longer operating room (OR) time, higher comorbidity index, and oral cavity and pharyngeal tumor sites. Predictors of wound-healing complications (15%) were longer OR time, volume of crystalloid given intraoperatively, and oral cavity and pharyngeal tumor sites. Predictors of wound infection (12%) were younger age, diabetes mellitus, and malnutrition. Conclusions Wound healing and infectious complications account for most complications in patients with head and neck cancer undergoing free flap reconstruction. Clean contaminated wounds are a significant predictor of wound complications. Advanced OR time, advanced age, and comorbidity status, including diabetes mellitus and malnutrition, are other important predictors. Crystalloid administration is also an important predictor of wound-healing complications, and this warrants further study.
Independent predictors of survival are unique in patients with oropharyngeal SCC treated with primary surgery. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1794-E1802, 2016.
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