Konrad Schwager

Pulsatile tinnitus: imaging and differential diagnosis.

BACKGROUNDnPulsatile tinnitus, unlike idiopathic tinnitus, usually has a specific, identifiable cause. Nonetheless, uncertainty often arises in clinical practice about the findings to be sought and the strategy for work-up.nnnMETHODSnSelective literature review and evaluation of our own series of patients.nnnRESULTSnPulsatile tinnitus can have many causes. No prospective studies on this subject are available to date. Pulsatile tinnitus requires both a functional organ of hearing and a genuine, physical source of sound, which can, under certain conditions, even be objectified by an examiner. Pulsatile tinnitus can be classified by its site of generation as arterial, arteriovenous, or venous. Typical arterial causes are arteriosclerosis, dissection, and fibromuscular dysplasia. Common causes at the arteriovenous junction include arteriovenous fistulae and highly vascularized skull base tumors. Common venous causes are intracranial hypertension and, as predisposing factors, anomalies and normal variants of the basal veins and sinuses. In our own series of patients, pulsatile tinnitus was most often due to highly vascularized tumors of the temporal bone (16%), followed by venous normal variants and anomalies (14%) and vascular stenoses (9%). Dural arteriovenous fistulae, inflammatory hyperemia, and intracranial hypertension were tied for fourth place (8% each).nnnCONCLUSIONnThe clinical findings and imaging studies must always be evaluated together. Thorough history-taking and clinical examination are the basis for the efficient use of imaging studies to reveal the cause of pulsatile tinnitus.

Imaging of Cerebrospinal Fluid Leaks

The present article provides an overview of epidemiology, clinical signs and symptoms, imaging techniques and specific imaging findings in cerebrospinal fluid leaks. Imaging protocols are supplemented with practical hints for invasive techniques. Emphasis is on the full scope of imaging findings in traumatic and nontraumatic cranial and spinal leaks.ZusammenfassungDer vorliegende Artikel gibt einen Überblick über Epidemiologie, Klinik, Bildgebungstechniken und spezielle Befunde bei Liquorlecks. Untersuchungsprotokolle werden um praktische Hinweise für invasive Verfahren ergänzt. Schwerpunkt ist die ganze Breite der Bildgebung bei traumatischen und nichttraumatischen kranialen und spinalen Leckagen.

Postoperative Cochlear Obliteration after Retrosigmoid Approach in Patients with Vestibular Schwannoma

Objective Vestibular schwannomas (VSNs) account for the vast majority of lesions located in the cerebellopontine angle (CPA). The goals of VSN surgery are possible total tumor removal, intact facial nerve function, and preservation of cochlear nerve function. In cases of pre‐ or postoperative deafness, restoration of hearing with auditory brainstem implant (ABI) or cochlear implant (CI) is a promising treatment option with normally better results in CI than in ABI. The aim of this retrospective study is to evaluate cochlear ossification or obliteration secondary to a retrosigmoid approach, which is important for later CI, especially in single‐sided deafness. Materials and Methods We retrospectively reviewed data from our suboccipital retrosigmoid operation database for the period from January 2008 to February 2015. A total of 65 patients with VSN could be analyzed retrospectively. The patients data (age, gender, side of operation, tumor entities, and the duration of follow‐up) were evaluated. The most recent T2‐weigted MRI exams were taken into account for the evaluation of cochlea. To compare left and right sides, the coronal reformatted images were reconstructed in a symmetrical way. Results Twenty‐two out of 65 (33%) patients had cochlear obliteration in our survey. The cochlear obliteration was more common in females (44 vs. 20% in males). The median follow‐up was 28 months. The size and the intrameatal extension of tumors could not be considered as factors influencing the cochlear obliteration rate. According to our survey, 33% of suboccipital approaches manifested cochlear obliteration to some extent. It was more common in females. The intrameatal extension of tumors played statistically no role in the occurrence of postoperative cochlear obliteration. Whether the prohibition of cochlear ossification can be best achieved by retrosigmoid approaches, compared to other approaches to the CPA, or not could be a subject of future studies.