Anatomy-Based Frequency Allocation in Cochlear Implantation: The Importance of Cochlear Coverage.

OBJECTIVES/HYPOTHESIS: This study aimed to compare the predicted anatomy-based frequency allocation of cochlear implant electrodes with the default standard frequencies. STUDY DESIGN: Retrospective study. METHODS: A retrospective analysis was performed using computed tomography (CT) images of patients who received cochlear implants at a tertiary referral center. Patients were excluded if they had any congenital or acquired cochlear anatomical anomalies. The CT images of the patients were uploaded to the surgical planning software. Two independent reviewers allocated the anatomical parameters of the cochlea. The software then used these parameters to calculate the frequency allocation for each electrode according to the type of electrode and the length of the organ of Corti (OC) in each patient. These anatomy-based frequency allocations were compared with the default frequency settings. MAIN OUTCOME MEASURE: Frequency-to-place mismatch in semitones. RESULTS: A total of 169 implanted ears in 102 patients were included in this study. The readings of the two reviewers were homogenous, with a Cronbach's alpha of 0.98. The mean anatomy-based frequency allocation was 487.3 ± 202.9 Hz in electrode 1; 9,298.6 ± 490.6 Hz in electrode 12. The anatomy-based frequency allocations were found to be significantly higher than the frequencies of the default frequencies for each corresponding electrode (one-sample t-test, P < .001). The frequency-to-place mismatch was negatively correlated with cochlear coverage and positively correlated with the cochlear duct length (Pearson correlation > 0.65, P < .003). CONCLUSIONS: The anatomy-based frequency allocation of each electrode is significantly different from the default frequency setting. This frequency-to-place mismatch was affected mainly by the cochlear coverage. LEVEL OF EVIDENCE: 3 Laryngoscope, 132:2224-2231, 2022.

Hydatid cyst of the heart with mitral valve stenosis; Case report.

Hydatid cyst of the heart is very rare, the left ventricle is the commonest site of myocardial involvement due to dominant left coronary vessels and thicker wall. Isolated cardiac involvement is extremely rare. Patients may be quite asymptomatic but the cyst may cause palpitation, dyspnea, chest pain, or when ruptured in to the cardiac or pericardial cavities may cause emergency presentations like anaphylactic reactions, sudden collapse due to pericardial tamponade or even sudden death. A middle age female presented with exertional shortness of breath for 2 years. Echocardiography showed mitral valve stenosis. Computerized tomography scan of the chest showed a big complicated hydatid cyst arising from the wall of the right ventricle. Median sternotomy was done with excision of the hydatid cyst, and repair of mitral stenosis by commissurotomy. The patient received three cycles of albendazole for three months. Surgery is the best options of treatment of cardiac hydatid disease, when the disease is affecting the pericardium complete excision may be possible, but when the myocardium is involved it may be difficult or even impossible to do complete excision, in this situation the cyst contents should be evacuated completely, preventing spillage is very mandatary to prevent recurrence. Care must be taken to avoid damage to the conductive system, the papillary muscles, the aortic and the mitral valves. Medical treatment with anthelminthic medications is used after surgery to reduce the recurrence rate.

Primary infected hydatid cyst of the thigh in a young lady; case report with literature review.

Hydatid disease present in certain parts of the world. Infection of the musculoskeletal system occur in less than 0.5%. A 24-year-old lady had a painful mass in the inner aspect of the right thigh. MRI of the thigh showed a mixed signal intensity lesion measured about 65*100 mm, the mass was related to the muscle and the superficial femoral artery and its cavity had multiple septations. During surgery an infected hydatid cyst of the muscle was found, evacuation was done with removal of the cyst. The patient was discharged next day and she received anthelminthic medications for 3 months. Hydatid cyst of the muscles present with gradually enlarging mass or complications such as nerve compression, infection or rupture. Treatment may be medical using anthelminthic medications. Complete surgical excision is the best surgical option; involvement of other organs should be excluded. Follow-up is recommended.