Although most of the recent studies have been focused on the postgadolinium enhancement, the noncontrast portion of the MR studies can be helpful in diagnosing alternative causes such as stroke, superior semicircular dehiscence, and other IAC masses. Volumetric measure of inner ear structures has been shown to be useful [67]. Although often not specifically mentioned, a sequence (typically heavily T2-weighted) that shows both perilymph and endolymph to help determine the area of the entire labyrinth is needed, and this is performed without IV contrast. MRI Head With IV Contrast There is no relevant literature regarding the use of MRI head with IV contrast in the evaluation of suspected MD. MRI Head Without and With IV Contrast There is no relevant literature regarding the use of MRI head without and with IV contrast in the evaluation of suspected MD. MRI Head Without IV Contrast There is no relevant literature regarding the use of MRI head without IV contrast in the evaluation of suspected MD. CT Head With IV Contrast There is no relevant literature regarding the use of CT head with IV contrast in the evaluation of suspected VBI. Dizziness and Ataxia CT Head Without and With IV Contrast There is no relevant literature regarding the use of CT head without and with IV contrast in the evaluation of suspected VBI. CT Head Without IV Contrast CT head without IV contrast may be useful in the evaluation of suspected VBI, although brain MRI is expected to be more sensitive for the detection of posterior fossa infarcts. CT Temporal Bone With IV Contrast There is no relevant literature regarding the use of CT temporal bone with IV contrast in the evaluation of suspected VBI. CT Temporal Bone Without and With IV Contrast There is no relevant literature regarding the use of CT temporal bone without and with IV contrast in the evaluation of suspected VBI.
Dizziness and Ataxia. Although most of the recent studies have been focused on the postgadolinium enhancement, the noncontrast portion of the MR studies can be helpful in diagnosing alternative causes such as stroke, superior semicircular dehiscence, and other IAC masses. Volumetric measure of inner ear structures has been shown to be useful [67]. Although often not specifically mentioned, a sequence (typically heavily T2-weighted) that shows both perilymph and endolymph to help determine the area of the entire labyrinth is needed, and this is performed without IV contrast. MRI Head With IV Contrast There is no relevant literature regarding the use of MRI head with IV contrast in the evaluation of suspected MD. MRI Head Without and With IV Contrast There is no relevant literature regarding the use of MRI head without and with IV contrast in the evaluation of suspected MD. MRI Head Without IV Contrast There is no relevant literature regarding the use of MRI head without IV contrast in the evaluation of suspected MD. CT Head With IV Contrast There is no relevant literature regarding the use of CT head with IV contrast in the evaluation of suspected VBI. Dizziness and Ataxia CT Head Without and With IV Contrast There is no relevant literature regarding the use of CT head without and with IV contrast in the evaluation of suspected VBI. CT Head Without IV Contrast CT head without IV contrast may be useful in the evaluation of suspected VBI, although brain MRI is expected to be more sensitive for the detection of posterior fossa infarcts. CT Temporal Bone With IV Contrast There is no relevant literature regarding the use of CT temporal bone with IV contrast in the evaluation of suspected VBI. CT Temporal Bone Without and With IV Contrast There is no relevant literature regarding the use of CT temporal bone without and with IV contrast in the evaluation of suspected VBI.