Large-scale annotated dataset for cochlear hair cell detection and classification.

Our sense of hearing is mediated by cochlear hair cells, of which there are two types organized in one row of inner hair cells and three rows of outer hair cells. Each cochlea contains 5-15 thousand terminally differentiated hair cells, and their survival is essential for hearing as they do not regenerate after insult. It is often desirable in hearing research to quantify the number of hair cells within cochlear samples, in both pathological conditions, and in response to treatment. Machine learning can be used to automate the quantification process but requires a vast and diverse dataset for effective training. In this study, we present a large collection of annotated cochlear hair-cell datasets, labeled with commonly used hair-cell markers and imaged using various fluorescence microscopy techniques. The collection includes samples from mouse, rat, guinea pig, pig, primate, and human cochlear tissue, from normal conditions and following in-vivo and in-vitro ototoxic drug application. The dataset includes over 107,000 hair cells which have been identified and annotated as either inner or outer hair cells. This dataset is the result of a collaborative effort from multiple laboratories and has been carefully curated to represent a variety of imaging techniques. With suggested usage parameters and a well-described annotation procedure, this collection can facilitate the development of generalizable cochlear hair-cell detection models or serve as a starting point for fine-tuning models for other analysis tasks. By providing this dataset, we aim to give other hearing research groups the opportunity to develop their own tools with which to analyze cochlear imaging data more fully, accurately, and with greater ease.

Large-scale annotated dataset for cochlear hair cell detection and classification.

Our sense of hearing is mediated by cochlear hair cells, localized within the sensory epithelium called the organ of Corti. There are two types of hair cells in the cochlea, which are organized in one row of inner hair cells and three rows of outer hair cells. Each cochlea contains a few thousands of hair cells, and their survival is essential for our perception of sound because they are terminally differentiated and do not regenerate after insult. It is often desirable in hearing research to quantify the number of hair cells within cochlear samples, in both pathological conditions, and in response to treatment. However, the sheer number of cells along the cochlea makes manual quantification impractical. Machine learning can be used to overcome this challenge by automating the quantification process but requires a vast and diverse dataset for effective training. In this study, we present a large collection of annotated cochlear hair-cell datasets, labeled with commonly used hair-cell markers and imaged using various fluorescence microscopy techniques. The collection includes samples from mouse, human, pig and guinea pig cochlear tissue, from normal conditions and following in-vivo and in-vitro ototoxic drug application. The dataset includes over 90'000 hair cells, all of which have been manually identified and annotated as one of two cell types: inner hair cells and outer hair cells. This dataset is the result of a collaborative effort from multiple laboratories and has been carefully curated to represent a variety of imaging techniques. With suggested usage parameters and a well-described annotation procedure, this collection can facilitate the development of generalizable cochlear hair cell detection models or serve as a starting point for fine-tuning models for other analysis tasks. By providing this dataset, we aim to supply other groups within the hearing research community with the opportunity to develop their own tools with which to analyze cochlear imaging data more fully, accurately, and with greater ease.

Functional Outcome After Simultaneous Vestibular Schwannoma Resection and Cochlear Implantation With Intraoperative Cochlear Nerve Monitoring.

OBJECTIVE: Electrically evoked auditory brainstem response audiometry has emerged as a suitable option to intraoperatively assess cochlear nerve function during vestibular schwannoma resection. This study aimed to analyze the functional outcome and implant usage of patients with preserved auditory nerve responses after simultaneous translabyrinthine schwannoma resection and cochlear implantation. STUDY DESIGN: Prospective study. SETTING: Tertiary referral center. METHODS: Patients with unilateral sporadic vestibular schwannoma underwent translabyrinthine tumor resection. Intraoperatively, electrically evoked auditory brainstem response audiometry was performed before and after tumor removal. Cochlear implantation was carried out if positive responses were detected after tumor removal indicating cochlear nerve function. Postoperatively, patients were biannually followed-up to assess aided sound field audiometry and word recognition as well as implant usage. RESULTS: Overall, 26 patients with vestibular schwannoma underwent translabyrinthine schwannoma resection. Out of these patients, 15 had positive cochlear nerve responses after tumor removal and concurrently received a cochlear implant. In 13 patients with histologically confirmed vestibular schwannoma, hearing improved by 23.7 ± 33.2 decibels and word recognition by 25.0 ± 42.4% over a mean follow-up period of 18 months. Overall, 12 included patients were regular cochlear implant users. CONCLUSION: Patients with vestibular schwannoma can benefit substantially from cochlear implantation. Intraoperative assessment of cochlear nerve function using electrically evoked auditory brainstem response audiometry can help to better identify individuals eligible for simultaneous vestibular schwannoma resection and cochlear implantation.

Investigation of inner ear drug delivery with a cochlear catheter in piglets as a representative model for human cochlear pharmacokinetics.

Hearing impairment is the most common sensory disorder in humans, and yet hardly any medications are licensed for the treatment of inner ear pathologies. Intricate pharmacokinetic examinations to better understand drug distribution within this complex organ could facilitate the development of novel therapeutics. For such translational research projects, animal models are indispensable, but differences in inner ear dimensions and other anatomical features complicate the transfer of experimental results to the clinic. The gap between rodents and humans may be bridged using larger animal models such as non-human primates. However, their use is challenging and impeded by administrative, regulatory, and financial hurdles. Other large animal models with more human-like inner ear dimensions are scarce. In this study, we analyzed the inner ears of piglets as a potential representative model for the human inner ear and established a surgical approach for intracochlear drug application and subsequent apical sampling. Further, controlled intracochlear delivery of fluorescein isothiocyanate-dextran (FITC-d) was carried out after the insertion of a novel, clinically applicable CE-marked cochlear catheter through the round window membrane. Two, six, and 24 hours after a single injection with this device, the intracochlear FITC-d distribution was determined in sequential perilymph samples. The fluorometrically assessed concentrations two hours after injection were compared to the FITC-d content in control groups, which either had been injected with a simple needle puncture through the round window membrane or the cochlear catheter in combination with a stapes vent hole. Our findings demonstrate not only significantly increased apical FITC-d concentrations when using the cochlear catheter but also higher total concentrations in all perilymph samples. Additionally, the concentration decreased after six and 24 hours and showed a more homogenous distribution compared to shorter observation times.

Surgical Anatomy of Temporalis Muscle Transfer with Fascia Lata Augmentation for the Reanimation of the Paralyzed Face: A Cadaveric Study.

Background The temporalis muscle flap transfer with fascia lata augmentation (FLA) is a promising method for smile reconstruction after facial palsy. International literature lacks a detailed anatomical analysis of the temporalis muscle (TPM) combined with fascia lata (FL) augmentation. This study aims to describe the muscle's properties and calculate the length of FL needed to perform the temporalis muscle flap transfer with FLA. Methods Twenty nonembalmed male (m) and female (f) hemifacial cadavers were dissected to investigate the temporalis muscle's anatomy. Results The calculated minimum length of FL needed is 7.03cm (f) and 5.99cm (m). The length of the harvested tendon is 3.16cm/± 1.32cm (f) and 3.18/± 0.73cm (m). The length of the anterior part of the temporalis muscle (aTPM) is 4.16/± 0.80cm (f) and 5.30/± 0.85cm (m). The length of the posterior part (pTPM) is 5.24/± 1.51cm (f) and 6.62/± 1.03cm (m). The length from the most anterior to the most posterior point (aTPMpTPM) is 8.60/± 0.98cm (f) and 10.18/± 0.79cm (m). The length from the most cranial point to the distal tendon (cTPMdT) is 7.90/± 0.43cm (f) and 9.79/± 1.11cm (m). Conclusions This study gives basic information about the temporalis muscle and its anatomy to support existing and future surgical procedures in their performance. The recommended minimum length of FL to perform a temporalis muscle transfer with FLA is 7.03cm for female and 5.99cm for male, and minimum width of 3 cm. We recommend harvesting some extra centimeters to allow adjusting afterward.

Interobserver variability of cochlear duct measurements in pediatric cochlear implant candidates.

PURPOSE: The objective of the study was to evaluate the proposed cochlear duct length estimation based on the cochlear 'A value'. Furthermore, we assessed the interobserver variability between radiology and otolaryngology attending physicians and otolaryngology trainees. METHODS: Thirteen pediatric cochlear implant candidates were retrospectively analyzed by three otolaryngology physicians (attending physician, second year, and fourth year trainees) and a radiology attending. The cochlear duct length was calculated based on the formula of Grover et al. The differences in acquired measurements between observers were compared using the Wilcoxon matched signed-rank test. RESULTS: The differences in measurements between the attending otolaryngologist and radiologist were not statistically different, while several significant differences were observed with regard to measurements of attending doctors compared to both residents. In particular, a significant difference between the second year otolaryngology resident and otolaryngology and radiology attending was observed for one side (right ear p = 0.034 and p = 0.012, respectively). Moreover, the fourth year resident calculated significantly different cochlear duct measurements when compared to the attending otolaryngologist (left ear p = 0.014) and radiologist (right ear p = 0.047). Interestingly, differently experienced otolaryngology residents provided significantly different measurements for both ears. CONCLUSIONS: Based on these results, cochlear duct length measurement according to the proposed method may be a reliable and cost-effective method. Indeed, otolaryngology training may be sufficient to provide measurements comparable to radiologists. On the other hand, additional efforts should be invested during otolaryngology training in terms of the evaluation of radiological imaging which may increase the capabilities of otolaryngology residents in this regard.

Intratympanic Substance Distribution After Injection of Liquid and Thermosensitive Drug Carriers: An Endoscopic Study.

OBJECTIVE: In the treatment of inner ear conditions, intratympanic injection emerges as an important drug delivery method. Novel compounds designed for intratympanic injection are routinely loaded in viscous drug carriers. To date, it is unclear if they can freely distribute in the middle ear. The aims of this study were to investigate the middle ear distribution of different drug carriers during intratympanic injection and to determine an optimal injection method for thermosensitive hydrogels. METHODS: Twenty-one human temporal bones were intratympanically injected with fluid drug carriers or poloxamer-407 hydrogels at different tympanic membrane injection sites (inferior, anterior-superior) using different needle types (Whitacre, Quincke). Fluid distribution was evaluated via an endoscopic view. Injection volume, duration, backflow, and overall safety were analyzed. RESULTS: Liquid drug carriers distribute effortlessly in the middle ear, whereas an additional ventilation hole is advantageous when applying thermosensitive hydrogels. The round window is coated with required volumes between 150 and 200 µl, irrespective of the injection position. Required volumes to also coat the stapedial footplate ranged from 310 to 440 µl. Use of the Whitacre-type needle reduced backflow to the ear canal and enabled longer tympanic membrane visibility when no additional ventilation hole was placed. CONCLUSION: Intratympanic injection is a safe and reliable method for the application of thermosensitive hydrogels. The round window niche is readily filled regardless of the injected formulation and injection position. Although fluid drug carriers distribute effortlessly in the middle ear, the placement of an additional ventilation hole might facilitate the application of viscous hydrogels.

Single-incision cochlear implantation and hearing evaluation in piglets and minipigs.

OBJECTIVES: Various animal models have been established and applied in hearing research. In the exploration of novel cochlear implant developments, mainly rodents have been used. Despite their important contribution to the understanding of auditory function, translation of experimental observations from rodents to humans is limited due to the size differences and genetic variability. Large animal models with better representation of the human cochlea are sparse. For this reason, we evaluated domestic piglets and Aachen minipigs for the suitability as a cochlear implantation animal model with commercially available cochlear implants. METHODS: Four domestic piglets (two male and two female) and six Aachen minipigs were implanted with either MED-EL Flex24 or Flex20 cochlear implants respectively, after a step-by-step surgical approach was trained with pig cadavers. Electrophysiological measurements were performed before, during and after implantation for as long as 56 days after surgery. Auditory brainstem responses, electrocochleography as well as electrically and acoustically evoked compound action potentials were recorded. Selected cochleae were further analyzed histologically or with micro-CT imaging. RESULTS: A surgical approach was established using a retroauricular single incision. Baseline auditory thresholds were 27 ± 3 dB sound pressure level (SPL; auditory brainstem click responses, mean ± standard error of the mean) and ranged between 30 and 80 dB SPL in frequency-specific responses (0.5 - 32 kHz). Follow-up measurements revealed deafness within the first two weeks after surgery, but some animals partially recovered to a hearing threshold of 80 dB SPL in certain frequencies as well as in click responses. Electrically evoked compound action potential thresholds increased within the first week after surgery, which led to lower stimulation responses or increase of necessary charge input. Immune reactions and consecutive scalar fibrosis following implantation were confirmed with histological analysis of implanted cochleae and may result in increased impedances. A three-dimensional minipig micro-CT segmentation revealed cochlear volumetric data similar to human inner ear dimensions. CONCLUSIONS: This study underlines the feasibility of cochlear implantation with clinically used cochlear implants in a large animal model with representative inner ear dimensions comparable to humans. To bridge the gap between small animal models and humans in translational research and to account for the structural and size differences, we recommend the minipig as a valuable animal model for hearing research. First insights into the induced trauma in minipigs after cochlear implant surgery and a partial hearing recovery present important data of the cochlear health changes in large animal cochleae.

Long-Term Swallowing Outcome and Dysphagia in Advanced Staged Head and Neck Squamous Cell Carcinomas after Radiotherapy.

Objective: To evaluate the impact of radiotherapy (RT) on dysphagia and long-term swallowing outcome in patients with stage III and IV head and neck squamous cell carcinomas (HNSCCs). Material and Methods: Between 2005 and 2008, 189 patients with HNSCCs underwent primary or adjuvant RT in a curative setting. Long-term swallowing outcome was evaluated in 50 patients. Among them, 26 were further eligible for prospective analysis of long-term swallowing and dysphagia outcome. Medical charts were retrospectively reviewed regarding pre- and post-treatment dysphagia (3 months after last irradiation setting) as well as persisting long-term dysphagia (2019−2021). Results: Pre-treatment dysphagia was observed in 24 (48%) of 50 patients, particularly in oropharyngeal or hypopharyngeal stage III−IV tumors (OR 9.3; p = 0.003). Conversely, 46 patients (92%) complained about post-treatment dysphagic symptoms, which were more commonly seen in patients with positive neck nodes (OR 10.5; p = 0.037). The post-treatment dysphagia rate dropped from 92% to 24% (p < 0.001) during surveillance, which was significantly linked to xerostomia (OR 5.77; p = 0.019), dysgeusia (OR 9.9; p = 0.036) and free flap reconstruction (OR 6.1; p = 0.022). Conclusion: Pretreatment dysphagia is common in advanced stage HNSCCs and almost all patients complain about dysphagia at the end of RT. Importantly, applied RT protocols did not affect long-term dysphagia, which improves significantly in the majority of patients over time. Meeting Information: Preliminary results have been presented at the 65th Annual Meeting of the Austrian Society of Otorhinolaryngology, 22−26 September 2021, Austria.

Feasibility of intraoperative motor evoked potential monitoring during tethered cord surgery in infants younger than 12 months.

PURPOSE: Feasibility, reliability, and safety assessment of transcranial motor evoked potentials (MEPs) in infants less than 12 months of age. METHODS: A total of 22 patients with a mean age of 33 (range 13-49) weeks that underwent neurosurgery for tethered cord were investigated. Data from intraoperative MEPs, anesthesia protocols, and clinical records were reviewed. Anesthesia during surgery was maintained by total intravenous anesthesia (TIVA). RESULTS: MEPs were present in all patients for the upper extremities and in 21 out of 22 infants for the lower extremities. Mean baseline stimulation intensity was 101 ± 20 mA. If MEPs were present at the end of surgery, no new motor deficit occurred. In the only case of MEP loss, preoperative paresis was present, and high baseline intensity thresholds were needed. MEP monitoring did not lead to any complications. TIVA was maintained with an average propofol infusion rate of 123.5 ± 38.2 µg/kg/min and 0.46 ± 0.17 µg/kg/min for remifentanil. CONCLUSION: In spinal cord release surgery, the use of intraoperative MEP monitoring is indicated regardless of the patient's age. We could demonstrate the feasibility and safety of MEP monitoring in infants if an adequate anesthetic regimen is applied. More data is needed to verify whether an irreversible loss of robust MEPs leads to motor deficits in this young age group.

BLS courses for refugees are feasible and induce commitment towards lay rescuer resuscitation.

BACKGROUND: High-quality Basic Life Support (BLS), the first step in the Utstein formula for survival, needs effective education for all kinds of population groups. The feasibility of BLS courses for refugees is not well investigated yet. METHODS: We conducted BLS courses including automated external defibrillator (AED) training for refugees in Austria from 2016 to 2019. Pre-course and after course attitudes and knowledge towards cardiopulmonary resuscitation (CPR) were assessed via questionnaires in the individuals' native languages, validated by native speaker interpreters. RESULTS: We included 147 participants (66% male; 22 [17-34] years; 28% <18 years) from 19 countries (74% from the Middle East). While the availability of BLS courses in the participants' home countries was low (37%), we noted increased awareness towards CPR and AED use after our courses. Willingness to perform CPR increased from 25% to 99%. A positive impact on the participants' perception of integration into their new environment was noted after CPR training. Higher level of education, male gender, age <18 years and past traumatizing experiences positively affected willingness or performance of CPR. CONCLUSION: BLS education for refugees is feasible and increases their willingness to perform CPR in emergency situations, with the potential to improve survival after cardiac arrest. Individuals with either past traumatizing experiences, higher education or those <18 years might be eligible for advanced life support education. Interestingly, these BLS courses bear the potential to foster resilience and integration. Therefore, CPR education for refuge should be generally offered and further evaluated.

[Vestibular schwannoma: Diagnosis-Therapy-Aftercare]. / Vestibularisschwannome: Diagnose ­ Therapie ­ Nachsorge.

Vestibular schwannomas can severely impair the quality of life of patients. Next to impaired hearing function, facial palsy is perceived as particularly disturbing in this context. Varying growth rates of these benign tumors complicate a prediction of functional impairment of cranial nerves. Therefore, a regular update on current therapeutic strategies and alternative treatment options is relevant for both physicians and patients.

Long-Term Outcome and Comparison of Treatment Modalities of Temporal Bone Paragangliomas.

INTRODUCTION: Temporal bone paragangliomas are rare tumors with high vascularization and usually benign entity. A variety of modalities, including gross total resection, subtotal resection, conventional or stereotactic radiotherapy including gamma-knife, embolization, and wait-and-scan strategy can be considered. The aim of this study was to compare long-term outcomes of different primary treatment modalities in temporal bone paragangliomas. MATERIALS AND METHODS: Patients with temporal bone paragangliomas treated between 1976 and 2018 at a tertiary referral center were retrospectively analyzed in this study. Collected patient data of 42 years were analyzed and long-term results including interdisciplinary management were assessed. Patient outcomes were compared within the different therapy modalities according to tumor control rate and complications. Clinical characteristics, radiological imaging, tumor extent and location (according to Fisch classification), symptoms, and follow-up were evaluated and a descriptive analysis for each treatment modality was performed. Tumor recurrence or growth progression and respective cranial nerve function before and after therapy were described. RESULTS: A total of 59 patients were treated with a single or combined treatment modality and clinical follow-up was 7 (13) years (median, interquartile range). Of the included patients 45 (76%) were female and 14 (24%) male (ratio 3:1) with a patient age range from 18 to 83 years. Total resection was performed on 31 patients, while 14 patients underwent subtotal resection. Eleven patients were treated with conventional primary radiotherapy or gamma-knife radiosurgery. Pulsatile tinnitus (n = 17, 29%) and hearing impairment (n = 16, 27%) were the most common symptoms in our patient group. Permanent lower cranial nerve deficits were observed only in patients with large tumors (Fisch C and D, n = 14, 24%). Among the 45 patients who were treated surgically, 88% of patients with Fisch A and B paragangliomas had no recurrent disease, while no tumor growth was perceived in 83% of patients with Fisch C and D paragangliomas. CONCLUSION: In conclusion, we propose surgery as a treatment option for patients with small tumors, due to a high control rate and less cranial nerve deficits compared to larger tumors. Although patients with Fisch C and D temporal bone paraganglioma can be treated surgically, only subtotal resections are possible in many cases. Additionally, frequent occurrence of cranial nerve deficits in those patients and tumor growth progression in long-term follow-up examinations make a combination of the therapy modalities or a primary radiotherapy more suitable in larger tumors.

A new nomogram to predict the need for tracheostomy in burned patients.

PURPOSE: To evaluate the impact of tracheostomy on complications, dysphagia and outcome in second and third degree burned patients. METHODS: Inpatient mortality, dysphagia, severity of burn injury (ABSI, TBSA) and complications in tracheotomized burn patients were compared to (I) non-tracheotomized burn patients and (II) matched tracheotomized non-burn patients. RESULTS: 134 (30.9%) out of 433 patients who underwent tracheostomy, had a significantly higher percentage of inhalation injury (26.1% vs. 7.0%; p < 0.001), higher ABSI (8.9 ± 2.1 vs. 6.0 ± 2.7; p < 0.001) and TBSA score (41.4 ± 19.7% vs. 18.6 ± 18.8%; p < 0.001) compared to 299 non-tracheotomized burn patients. However, complications occurred equally in tracheotomized burn patients and matched controls and tracheostomy was neither linked to dysphagia nor to inpatient mortality at multivariate analysis. In particular, dysphagia occurred in 6.2% of cases and was significantly linked to length of ICU stay (OR 6.2; p = 0.021), preexisting neurocognitive impairments (OR 5.2; p = 0.001) and patients' age (OR 3.4; p = 0.046). A nomogram was calculated based on age, TBSA and inhalation injury predicting the need for a tracheostomy in severely burned patients. CONCLUSION: Using the new nomogram we were able to predict with significantly higher accuracy the need for tracheostomy in severely burned patients. Moreover, tracheostomy is safe and is not associated with higher incidenc of complications, dysphagia or worse outcome.

WITHDRAWN: Subsegmental Thrombus in COVID-19 Pneumonia: Immuno-Thrombosis or Pulmonary Embolism? Data Analysis of Hospitalized Patients with Coronavirus Disease.

This article has been withdrawn at the request of the author(s). The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Can volumetric measurement be used in the selection of treatment for inguinoscrotal hernias?

OBJECTIVE: Inguinoscrotal hernias are often qualified subjectively as big, giant, scrotal, etc. In order to classify this type of hernia, objective criteria are needed. For this purpose, we aimed to introduce a scrotal volume measurement-based classification system and propose a corresponding surgical plan (open or laparoscopic surgery, anterior or posterior repair) based on volumetric data. MATERIAL AND METHODS: Between October 2012 and October 2013, 30 consecutive male patients with a mean age of 59.5 years (range: 36 to 82 years) presenting with unilateral ISH were included in this retrospective study. Physical measurements in the upright position and computerized tomography measurements using the Valsalva maneuver were obtained from all patients. RESULTS: Of the 30 patients, 26 patients had scrotal volumes less than 1000 mL, two patients had SVs between 1001 and 2000 mL, one patient had an SV between 2001 and 3000 mL, and one patient had an SV greater than 3000 mL. Laparoscopic total extraperitoneal repair was performed in patients with scrotal volumes inferior to 1000 mL. In three patients with scrotal volumes between 1000 and 3000 mL, an open posterior approach was used. In one patient with a scrotal volume superior to 3000 mL, no surgical intervention was performed due to the patient's cardiac comorbidity. CONCLUSION: By establishing a common language among surgeons, we believe that the volumetric measurement-based scrotal hernia classification system proposed in this study will lead to further studies on the subject.

A possible cause of epistaxis: increased masked hypertension prevalence in patients with epistaxis.

INTRODUCTION: Epistaxis and hypertension are frequent conditions in the adult population. Masked hypertension is defined as a clinical condition in which a patient's office blood pressure level is <140/90mmHg, but the ambulatory or home blood pressure readings are in the hypertensive range. Many studies have proved that hypertension is one of the most important causes of epistaxis. The prevalence of this condition in patients with epistaxis is not well defined. OBJECTIVE: This study aimed to evaluate the prevalence of masked hypertension using the results of office blood pressure measurement compared with the results of ambulatory blood pressure monitoring. METHODS: Sixty patients with epistaxis and 60 control subjects were enrolled in the study. All patients with epistaxis and controls without history of hypertension underwent physical examination, including office blood pressure measurement, ambulatory or home blood pressure, and measurement of anthropometric parameters. RESULTS: Mean age was similar between the epistaxis group and the controls - 21-68 years (mean 42.9) for the epistaxis group and 18-71 years (mean 42.2) for the control group. A total of 20 patients (33.3%) in the epistaxis group and 7 patients (11.7%) in the control group (p=0.004) had masked hypertension. Night-time systolic blood pressure was significantly higher in patients with epistaxis than in the control group (p<0.005). However, no significant difference was found in daytime systolic blood pressure between the control group and the patients with epistaxis (p=0.517). CONCLUSION: This study demonstrates increased masked hypertension prevalence in patients with epistaxis. We suggest that all patients with epistaxis should undergo ambulatory or home blood pressure to detect masked hypertension, which could be a possible cause of epistaxis.

Using intraoperative dynamic contrast-enhanced T1-weighted MRI to identify residual tumor in glioblastoma surgery.

OBJECT: The goal of surgery in high-grade gliomas is to maximize the resection of contrast-enhancing tumor without causing additional neurological deficits. Intraoperative MRI improves surgical results. However, when using contrast material intraoperatively, it may be difficult to differentiate between surgically induced enhancement and residual tumor. The purpose of this study was to assess the usefulness of intraoperative dynamic contrast-enhanced T1-weighted MRI to guide this differential diagnosis and test it against tissue histopathology. METHODS: Preoperative and intraoperative dynamic contrast-enhanced MRI was performed in 21 patients with histopathologically confirmed WHO Grade IV gliomas using intraoperative 3-T MRI. Standardized regions of interest (ROIs) were placed manually at 2 separate contrast-enhancing areas at the resection border for each patient. Time-intensity curves (TICs) were generated for each ROI. All ROIs were biopsied and the TIC types were compared with histopathological results. Pharmacokinetic modeling was performed in the last 10 patients to confirm nonparametric TIC analysis findings. RESULTS: Of the 42 manually selected ROIs in 21 patients, 25 (59.5%) contained solid tumor tissue and 17 (40.5%) retained the brain parenchymal architecture but contained infiltrating tumor cells. Time-intensity curves generated from residual contrast-enhancing tumor and their preoperative counterparts were comparable and showed a quick and persistently increasing slope ("climbing type"). All 17 TICs obtained from regions that did not contain solid tumor tissue were undulating and low in amplitude, compared with those obtained from residual tumors ("low-amplitude type"). Pharmacokinetic findings using the transfer constant, extravascular extracellular volume fraction, rate constant, and initial area under the curve parameters were significantly different for the tumor mass, nontumoral regions, and surgically induced contrast-enhancing areas. CONCLUSIONS: Intraoperative dynamic contrast-enhanced MRI provides quick, reproducible, high-quality, and simply interpreted dynamic MR images in the intraoperative setting and can aid in differentiating surgically induced enhancement from residual tumor.

Intraoperative magnetic resonance spectroscopy for identification of residual tumor during low-grade glioma surgery: clinical article.

OBJECT: The authors had previously shown that 3-T intraoperative MRI (ioMRI) detects residual tumor tissue during low-grade glioma and that it helps to increase the extent of resection. In a proportion of their cases, however, the ioMRI disclosed T2-hyperintense areas at the tumor resection border after the initial resection attempt and prompted a differential diagnosis between residual tumor and nontumoral changes. To guide this differential diagnosis the authors used intraoperative long-TE single-voxel proton MR spectroscopy (ioMRS) and tested the correlation of these findings with findings from pathological examination of resected tissue. METHODS: Patients who were undergoing surgery for hemispheric or insular WHO Grade II gliomas and were found to have T2 changes around the resection cavity at the initial ioMRI were prospectively examined with ioMRS and biopsies were taken from corresponding localizations. In 14 consecutive patients, the ioMRS diagnosis in 20 voxels of interest was tested against the histopathological diagnosis. Intraoperative diffusion-weighted imaging (ioDWI) was also performed, as a part of the routine imaging, to rule out surgically induced changes, which could also appear as T2 hyperintensity. RESULTS: Presence of tumor was documented in 14 (70%) of the 20 T2-hyperintense areas by histopathological examination. The sensitivity of ioMRS for identifying residual tumor was 85.7%, the specificity was 100%, the positive predictive value was 100%, and the negative predictive value was 75%. The specificity of ioDWI for surgically induced changes was high (100%), but the sensitivity was only 60%. CONCLUSIONS: This is the first clinical series to indicate that ioMRS can be used to differentiate residual tumor from nontumoral changes around the resection cavity, with high sensitivity and specificity.