T2-images can be variable in ILH according to the haemorrhage stage but, like in our case, are useful to differentiate ILH from the rest of entities that appear typically hyperintense on T1-weighted images. Because this T1 hyperintensity could also be explained by the presence of fat seen in the uncommon intralabyrinthine lipoma, fat-suppressed T1-weighted images may be used to distinguish both entities, particularly in cases of atypical clinic presentation without abrupt onset of the symptoms. The typical precontrast T1-hyperintensity seen in ILH in the cochlea, vestibule and/or semicircular canals is due to the meta-haemoglobin found during subacute period within normally fluid-filled space of labyrinth. In T1-weighted images, the perilymph and the endolymph are normally isointense to the cerebrospinal fluid. MRI is a very helpful and initial diagnostic tool in the evaluation of SSNHL. Ĭlinical diagnosis of ILH is very difficult and has to rule out many differential diagnoses such as labyrinthine hydrops or Menière’s disease, non-haemorrhagic labyrinthitis, cochleovestibular neuritis and schwannoma, labyrinthine fistula and ischaemia of the internal auditory artery. In most cases, the aetiology of ILH remains unclear, but has been associated with anticoagulant therapy, hypertension, haematologic disorders (coagulopathies, sickle cell anaemia, pernicious anaemia, leukaemia), trauma (head trauma, barotrauma or local surgery) endolymphatic sac tumours and labyrinthitis (viral, bacterial, postoperative or autoimmune, the latter bilateral and often with other systemic involvement). Intralabyrinthine haemorrhage (ILH) is a rare cause of SSNHL. About 85% of the SSNHL are idiopathic and managed with empirical treatment. SSNL is typically unilateral and may be sudden or rapidly progressive, partial or complete and improves spontaneously in 65% of patients within two weeks. Sudden sensorial hearing loss (SSNHL) is defined as a sensorineural audiometric loss of 30 or more dB within not more than 72 hours and consecutively over three pure tone frequencies.
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