Edward P Lindell | PubMed Health

PubMed2007

Scalar localization of the electrode array after cochlear implantation: a cadaveric validation study comparing 64-slice multidetector computed tomography with microcomputed tomography.

HYPOTHESIS: Improved resolution available with 64-slice multidetector computed tomography (MDCT) could potentially be used clinically to localize the cochlear implant (CI) electrode array within the basal turn. BACKGROUND: In CI surgery, the electrode array should be inserted into and remain within the scala tympani to avoid injury to Reissner's membrane and the scala media. Correlating the position of the electrode in the basal turn with surgical technique and implant design could be helpful in improving outcomes. METHODS: After a standard left mastoid exposure of the round window niche through the facial recess performed on a cadaver head, an electrode array from a Nucleus Softip Contour CI was fully inserted through a cochleostomy. The head was then scanned axially on a 64-slice MDCT with 0.4-mm slice thickness and reconstructed into the oblique axial, oblique coronal, and oblique sagittal planes of the cochlea. The temporal bone was then harvested and imaged on a microcomputed tomographic scanner using 20-microm slice thickness. Identical reconstructions were made and compared with the 64-slice images to confirm exact location of the electrode array. RESULTS: The 64-slice MDCT accurately localized the electrode array to the scala tympani. This was best demonstrated in the oblique sagittal plane, identifying the electrode array in the posterior inferior portion of the basal turn, posterior to the spiral lamina. CONCLUSION: This ex vivo validation study suggests that 64-slice MDCT has the potential to allow accurate localization of the CI electrode array within the basal turn of the cochlea.

Cadaver↗

PubMed2005

Gadolinium encephalopathy in a patient with renal failure.

Gadolinium chelates are extensively used in MRI studies. Neurotoxicity due to gadolinium chelates is minimal and uncommon. A 57-year-old woman in renal failure developed a subacute encephalopathy after inadvertent repetitive gadolinium contrast administration. An unusual MRI appearance with CSF hyperintensity due to gadolinium diffusion into the CSF is also shown.

Amnesia, Retrograde↗

PubMed2004

Acquired cerebral hemiatrophy: idiopathic?

The authors report the case of a young man with acquired cerebral hemiatrophy that was progressive initially but stabilized after a few months. He did not have any seizure throughout the course of his illness. No definite cause was evident despite extensive investigations. He did have a slight increase in white cell count on a cerebrospinal fluid study done during the progressive phase of his illness suggesting that an unidentified infective or inflammatory illness may have resulted in the cerebral hemiatrophy. The authors suggest that Rassmusen's encephalitis may in fact be a spectrum with the typical descriptions representing one end. The importance of multimodality imaging in evaluating patients with cerebral hemiatrophy is discussed.

Adult↗