Imaging of the human cochlea using micro-computed tomography before and after cochlear implantation: comparison with cone-beam computed tomography.

PURPOSE: Analysis of cochlear structures and postoperative temporal bone (TB) imaging are gaining importance in the evaluation of cochlear implantation (CI°). Our aims were to explore the microarchitecture of human cochlea using micro-computed tomography (µCT), analyze electrode's placement inside cochlea after CI°, and compare pre-/post-implantation µCT scans with cone-beam CT (CBCT) scans of same TBs. METHODS: Cadaveric TBs were scanned using µCT and CBCT then underwent CI° using straight electrodes. Thereafter, they underwent again µCT and CBCT-imaging. RESULTS: Ten TBs were studied. µCT allowed visualization of scala tympani, scala vestibuli, basilar membrane, osseous spiral lamina, crista fenestrae, and spiral ligament. CBCT showed same structures except spiral ligament and crista fenestrae. After CI°, µCT and CBCT displayed the scalar location and course of electrode array within the cochlea. There were 7 cases of atraumatic electrode insertion and 3 cases of insertion trauma: basilar membrane elevation, electrode foldover with limited migration into scala vestibuli, and electrode kinking with limited migration into scala vestibuli. Insertion trauma was not correlated with cochlea's size or crista's maximal height but with round window membrane diameter. Resolution of µCT was higher than CBCT but electrode artifacts were similar. CONCLUSIONS: µCT was accurate in visualizing cochlear structures, and course and scalar position of electrode array inside cochlea with any possible trauma to cochlea or array. CBCT offers a good alternative to µCT in clinical practice for cochlear imaging and evaluation of CI°, with lower radiation and higher resolution than multi-slice CT. Difficulties related to non-traumatic CI° are multifactorial.

Cavernous Sinus Thrombosis Linked to COVID-19 Infection: a Case Report.

The severity of SARS-CoV-2 virus infection is mainly related to its respiratory complications. However, it can also lead to a large variety of thromboembolic events. Symptoms may include headache, fever, and neurological disorders. Since 2020, the clinical presentation of COVID-19 infection has become increasingly varied, leading in some cases to complex symptom associations, including numerous neurological symptoms. SARS-CoV-2 may lead to neurotropism which could reach the central nervous system and all cranial nerves. Cavernous sinus thrombosis is a rare condition and may occur as a complication of ear, nose, and throat (ENT) or facial infections. A 73-year-old man without personal or family history of thrombosis was referred to the emergency room for a sudden appearance of diplopia and ptosis, 3 days after testing positive for COVID-19 infection. An initial head CT-scan found no signs of stroke. He underwent a cerebral MRI 7 days later, which revealed a thrombosis of his right cavernous sinus. A brain CT scan 7 days later showed regression of the thrombosis with complete recanalization of the cavernous sinus. This was accompanied by a complete regression of diplopia and fever. He was discharged from the hospital 10 days after hospital admission. In this case report, we describe a rare event of cavernous thrombophlebitis following a COVID-19 infection.