American College of Medical Genetics and Genomics guideline for the clinical evaluation and etiologic diagnosis of hearing loss.

Hearing loss is a common and complex condition that can occur at any age, can be inherited or acquired, and is associated with a remarkably wide array of etiologies. The diverse causes of hearing loss, combined with the highly variable and often overlapping presentations of different forms of hearing loss, challenge the ability of traditional clinical evaluations to arrive at an etiologic diagnosis for many deaf and hard-of-hearing individuals. However, identifying the etiology of a hearing loss may affect clinical management, improve prognostic accuracy, and refine genetic counseling and assessment of the likelihood of recurrence for relatives of deaf and hard-of-hearing individuals. Linguistic and cultural identities associated with being deaf or hard of hearing can complicate access to and the effectiveness of clinical care. These concerns can be minimized when genetic and other health-care services are provided in a linguistically and culturally sensitive manner. This guideline offers information about the frequency, causes, and presentations of hearing loss and suggests approaches to the clinical evaluation of deaf and hard-of-hearing individuals aimed at identifying an etiologic diagnosis and providing informative and effective patient education and genetic counseling.

Chondroblastoma-like chondroma of soft tissue: report of the first case in the base of skull.

Chondroblastoma-like chondroma (CLC) of soft tissue is a rare benign neoplasm that usually involves the soft tissues of the hand. This report describes the first case of CLC of soft tissue arising in the base of the skull. A 33-year-old man was seen with a slow growing mass in the right parotid region of his face. The noncontrast computed tomographic scans showed an 8.5-cm mass with calcifications involving the right masticator space and extending through the bone into the middle cranial fossa. The radiologic differential diagnosis included osteosarcoma, leiomyosarcoma, chondrosarcoma, and giant cell tumor. During surgery, the large lateral skull base tumor appeared to involve the middle and infratemporal fossae and eroded the surrounding bone. Although the tumor was removed piecemeal, total excision was performed. On microscopic examination, the tumor displayed lobules of mature hyaline cartilage with numerous chondroblasts, coarse calcifications including chicken wire calcifications, and scattered osteoclasts. No atypia, mitoses, necrosis, or osteoid formation was seen. The tumor was diagnosed as chondroma with chondroblastoma features of the soft tissue. His postoperative clinical course was uneventful; however, after 7 months, he had a local recurrence identified on follow-up magnetic resonance imaging. He underwent repeat surgical excision of the tumor, which showed similar histology as the previous excision. This large skull based tumor eroding the bone, which clinically and radiologically mimicked a malignant process, was an unusual presentation of a benign cartilaginous neoplasm. Pathologists should be aware that CLC may occur in the base of the skull and this lesion should be differentiated from the other benign or malignant tumors arising in this area. These lesions have a potential for local recurrence; hence, a close follow-up is recommended.

Temporal Bone Fractures Caused by Ballistic Projectiles: A Systematic Review.

OBJECTIVE: Ballistic injuries to the temporal bone are uncommon but devastating injuries that damage critical neurovascular structures. This review describes outcomes after ballistic injuries to the temporal bone and offers initiatives for standardized high-quality future research. DATA SOURCES: A systematic search of PubMed, Embase, and Cochrane. REVIEW METHODS: Studies in the review included adults who experienced temporal bone fractures due to gunshot wounds and survived longer than 48 hours. Individual case reports were excluded. The various searches returned 139 results, of which 6 met inclusion criteria. RESULTS: Most of the included studies are case series with low-level evidence that report a wide range of outcomes and follow-up. Outcomes include demographic patient information, audiologic outcomes, vascular injuries, intracranial complications, facial nerve function, and surgical indications. CONCLUSION: This review is the first to characterize the nature and progression of patients who experienced gunshot wounds to the temporal bone. Although all patients share an etiology of injury, they often have vastly different hospital courses and outcomes. This review provides a basis for future studies to guide care for these injuries, as most of the existing literature includes small dated case series.

Trans-labyrinthine Infra-trigeminal Approach for Recurrent Pontomedullary Cavernoma: A Step-wise Technical Note.

Recurrent brainstem cavernoma is a challenging lesion due to the neurological risks associated with different surgical approaches. In this technical report, we present a 35-year-old female with a history of multiple brain cavernomas. She underwent midline suboccipital craniotomy and trans-fourth ventricle approach for resection of the brain stem cavernoma following two major bleeding episodes, one year prior to the presentation. Following the trans-labyrinthine infra-trigeminal approach, the patient recovered well postoperatively with a baseline neuro exam and was discharged to acute rehab on postoperative day 5 (POD5). The translabyrinthine approach is a safe and effective corridor for pontine or pontomedullary lesions in carefully selected patients. Appropriate selection of surgical approach (based on location), meticulous surgical technique, and intraoperative neuromonitoring help in maximizing surgical resection while minimizing neurological deficits.

Algorithm for reconstruction after endoscopic pituitary and skull base surgery.

INTRODUCTION: The expanding role of endoscopic skull base surgery necessitates a thorough understanding of the indications, techniques, and limitations of the various approaches to reconstruction. The technique and outcomes of endoscopic skull base reconstruction remain incompletely described in the literature. STUDY DESIGN AND METHODS: Patients undergoing endoscopic skull base surgery underwent an algorithmic approach to reconstruction based on tumor location, defect size, and presence of intraoperative cerebrospinal fluid (CSF) leak. A prospective database was reviewed to determine the overall efficacy of reconstruction and to identify risk factors for postoperative CSF leak. RESULTS: The diagnosis in the 127 patients in this series included pituitary tumor in 70 (55%) patients, encephalocele in 16 (12.6%) patients, meningioma in 11 (8.7%) patients, craniopharyngioma in 9 (7.1%) patients, and chordoma in 6 (4.7%) patients. Successful reconstruction was initially achieved in 91.3% of patients. Eleven (8.7%) patients experienced postoperative CSF leak, 10 of which resolved with lumbar drainage alone. One (0.8%) patient required revision surgery. Correlation between postoperative CSF leak and study variables revealed a statistically significant longer duration of surgery (243 vs. 178 min, P = .008) and hospitalization (12.1 vs. 4.5 days, P < .0001) and a trend toward larger tumors (mean, 3.2 vs. 2.3 cm; P = .058) in patients experiencing postoperative CSF leak. CONCLUSION: The algorithm for reconstruction after endoscopic surgery presented in this study is associated with excellent overall efficacy. A greater understanding of risk factors for postoperative CSF leak is imperative to achieve optimal results.

The role of oral fluid intake following adeno-tonsillectomy.

OBJECTIVE: To compare the incidence of complications following pediatric adeno-tonsillectomy (T&A) in patients who are encouraged to drink oral liquid versus patients who drink on a voluntary basis. METHODS: This is a prospective, randomized, non-blinded study performed in a tertiary care medical center. Ninety-three otherwise healthy pediatric patients aged 2-12 years undergoing ambulatory T&A by a single surgeon were included in the study. Forty four patients were encouraged to drink 240 ml of clear liquid prior to discharge while 49 patients drank on a voluntary basis. Patients were followed prospectively for the incidence of emesis, dehydration and other complications. RESULTS: Overall, emesis was experienced by 18% of patients in the post anesthesia care unit (PACU) and by 20% at home. Fifty percent of patients in the encouraged group versus 31% in the voluntary group reached the goal volume of oral liquids (p<0.05). The incidence of emesis was higher in both the encouraged (41% versus 14%) and voluntary group (40% versus 26%) when the goal volume of 240 ml was reached. There was no statistically significant difference between the two groups in terms of duration of PACU stay, incidence of emesis, number of episodes of emesis or volume of emesis. Further, there was no difference between the two groups in terms of post-operative complications including dehydration. CONCLUSIONS: The current practice of a mandatory trial of oral fluid intake in the post-operative period may not be a necessary requirement for discharge. Further, mandatory oral fluids may result in a higher incidence of emesis.

DNA sequence analysis and genotype-phenotype assessment in 71 patients with syndromic hearing loss or auditory neuropathy.

OBJECTIVES: Aetiological assessment of 71 probands whose clinical presentation suggested a genetic syndrome or auditory neuropathy. METHODS: Sanger sequencing was performed on DNA isolated from peripheral blood or lymphoblastoid cell lines. Genes were selected for sequencing based on each patient's clinical presentation and suspected diagnosis. Observed DNA sequence variations were assessed for pathogenicity by review of the scientific literature, and mutation and polymorphism databases, through the use of in silico tools including sorting intolerant from tolerant (SIFT) and polymorphism phenotyping (PolyPhen), and according to the recommendations of the American College of Medical Genetics and Genomics for the interpretation of DNA sequence variations. Novel DNA sequence variations were sought in controls. RESULTS: DNA sequencing of the coding and near-coding regions of genes relevant to each patient's clinical presentation revealed 37 sequence variations of known or uncertain pathogenicity in 9 genes from 25 patients. 14 novel sequence variations were discovered. Assessment of phenotypes revealed notable findings in 9 patients. CONCLUSIONS: DNA sequencing in patients whose clinical presentation suggested a genetic syndrome or auditory neuropathy provided opportunities for aetiological assessment and more precise genetic counselling of patients and families. The failure to identify a genetic aetiology in many patients in this study highlights the extreme heterogeneity of genetic hearing loss, the incompleteness of current knowledge of aetiologies of hearing loss, and the limitations of conventional DNA sequencing strategies that evaluate only coding and near-coding segments of genes.

Cochlear implant electrode misplacement: incidence, evaluation, and management.

OBJECTIVES/HYPOTHESIS: To review the presentation and management of improper electrode array placement, and to help guide clinical decision-making. STUDY DESIGN: Retrospective case series. METHODS: Pediatric and adult cochlear implant patients managed from January 2001 to present whose electrode arrays were not placed properly within the cochlea or extended beyond the cochlea into the internal auditory canal or adjacent structures. RESULTS: Four patients, three pediatric and one adult, were identified from over 824 cases (< 1%) managed over the study duration. All cases had normal cochlear anatomy. These cases were initially identified due to poor auditory skill development or absent behavioral responses following implantation, which prompted imaging. Two patients presented several years after surgery. Sites of improper placement included the eustachian tube, vestibule, internal carotid artery canal, and internal auditory canal (IAC). Intraoperative findings and management are reviewed. CONCLUSIONS: Electrode array malpositioning is a rare, but serious and correctable complication in cochlear implant surgery. A multidisciplinary approach, including prompt audiologic evaluation and imaging, is important, particularly when benefit from the implant is limited or absent. Management of electrode arrays in the IAC may be more challenging.

Comprehensive diagnostic battery for evaluating sensorineural hearing loss in children.

OBJECTIVE: Selection of diagnostic tests for children with sensorineural hearing loss (SNHL) is influenced by clinical suspicion. Testing results reported in the literature are similarly biased. We evaluate the usefulness of a comprehensive diagnostic battery for each child. STUDY DESIGN: Retrospective review. SETTING: Tertiary care university hospital. PATIENTS: A total of 270 children referred for severe to profound SNHL between January 2002 and June 2009. INTERVENTIONS: Results of the following were reviewed: magnetic resonance imaging, computed tomography, renal ultrasound, electrocardiography, fluorescent treponemal antibody absorption test, connexin 26 sequencing, genetic consultation, and ophthalmologic consultation. MAIN OUTCOME MEASURE: Diagnostic yield of each test was determined. RESULTS: Each diagnostic test or consultation was completed by at least 95% of patients for whom it was ordered. Magnetic resonance imaging revealed abnormalities explaining SNHL in 24% of patients. Computed tomography showed inner ear anomalies in 18% of patients. Biallelic connexin 26 mutations were found in 15%. Renal ultrasound found anomalies in 4% of patients. Electrocardiography found 1% of patients with prolonged QT intervals. Fluorescent treponemal antibody absorption test result was positive in 0.5%. Genetic consultation found a genetic cause for hearing loss in 25%. Ophthalmologic consultation found abnormalities associated with hearing loss in 8%. CONCLUSION: Diagnostic radiologic imaging is the highest yielding test for evaluating children with SNHL. Connexin 26 sequencing identifies a nearly nonoverlapping subset of children compared with imaging. Specialty consultations, particularly from a clinical geneticist, can improve diagnostic yield. Other tests, although of lower diagnostic yield for SNHL, can identify important diseases that significantly affect patient health.

Inner ear anomalies in congenital aural atresia.

OBJECTIVES: To define the prevalence of inner ear anomalies in aural atresia patients and to recognize patterns of developmental anomalies in aural atresia patients. STUDY DESIGN: Retrospective review. SETTING: Academic medical center. INTERVENTION: Physical exam, audiometry, and temporal bone CT in selected patients. PATIENTS: Pediatric patients with aural atresia. MAIN OUTCOME MEASURE: Prevalence of inner ear anomalies and coexisting facial paralysis or sensorineural hearing loss. RESULTS: In this series of 118 patients with aural atresia, associated facial palsy was seen in 13%, whereas inner ear anomalies were present in 22%, including all patients with facial palsy. Interestingly, the inner ear anomalies often did not display a significant sensorineural hearing loss. Bilateral inner ear anomalies were frequently encountered despite unilateral atresia. Most anomalies involved the semicircular canals including several uncommon variants of posterior semicircular canal anatomy. CONCLUSION: Inner ear anomalies are common in the presence of aural atresia, especially when there is concurrent congenital facial palsy. The presence of inner ear anomalies should be recognized as a common feature of craniofacial microsomia.

Characteristics of malfunctioning channels in pediatric cochlear implants.

OBJECTIVES/HYPOTHESIS: To examine the characteristics of pediatric cochlear implant channel malfunction preceding device failure. STUDY DESIGN: : Retrospective review. METHODS: All pediatric patients who underwent cochlear implantation at a tertiary academic medical center were reviewed regarding device type, reason for replacement, time to replacement, and timing and pattern of channel faults in failed versus nonfailed devices. RESULTS: Between 1993 and 2008, 264 pediatric cochlear implantations were performed. With an average 894-day follow-up, the replacement rate was 9.5% (25/264). Reasons for replacement were device failure (6.4%), medical/surgical failure (2.3%), and obsolescence (0.8%). Replacement rates were comparable among Advanced Bionics (13.3%), Cochlear Corporation (6.3%), and MED-EL (10.3%) devices. Fifty-two cochlear implants developed at least one channel fault, and 13 eventually progressed to failure requiring replacement. MED-EL devices comprised 12 of these 13 failures. At the 12-month follow-up interval, one, three, and five channel faults predicted 40%, 75%, and 100% probabilities of eventual electrode failure, respectively. Channels destined to fail demonstrated small, yet statistically significant, impedance elevations 12 months before failure and large elevations 3 months before failure. CONCLUSIONS: Replacement of cochlear implants in pediatric patients is common and is due to device malfunction about one half of the time. Earlier initial channel fault, earlier subsequent channel faults, adjacent channel faults, and a greater total number of channel faults were associated with the need for replacement surgery. Elevations in a channel's impedance should raise the concern for an impending failure. These predictors can help the cochlear implant team when considering surgery to replace the device.

Catheter- and antibiotic-related complications of ambulatory intravenous antibiotic therapy for chronic refractory rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis has several features of a prolonged bacterial infection including positive bacterial cultures and abnormal computed tomography findings such as mucosal thickening and hyperostotic bone. Recent studies have suggested that chronic rhinosinusitis may be treated successfully by outpatient parenteral antibiotic treatment (OPAT). In this setting, antibiotics are administered through a peripherally inserted central catheter (PICC). This study evaluates complications arising from OPAT for chronic rhinosinusitis. METHODS: A chart review was performed of 177 patients who underwent OPAT for chronic rhinosinusitis. RESULTS: PICC line-related infections (4/177, 2%)) included line thrombosis in three patients and septicemia in one patient. In the three patients with line thrombosis, the PICC lines were removed and replaced, allowing for completion of the antibiotic course. Antibiotic complications (29/177, 16%) included four patients with transient neutropenia and one patient with elevated liver function tests. Of the four patients with neutropenia, only one required a change in antibiotics. The patient with elevated liver function tests did not require a change in antibiotics. Minor complications from antimicrobial treatment such as rash, itchiness, flushing, and diarrhea were reported by 25 patients, 9 of these patients required a change in antibiotics. There were no permanent complications or deaths in this study. CONCLUSION: Intravenous antimicrobial treatment administered through a PICC line in an outpatient setting is well-tolerated for chronic rhinosinusitis. Although PICC line and antibiotic-related complications are relatively infrequent, the physician should be aware of these complications and consider them in selecting patients for OPAT.