Citations

Background and objectives: We report a comprehensive clinical, radiological, neuropsychometric and pathological evaluation of a woman with a clinical diagnosis of AD dementia (ADem), but whose autopsy demonstrated widespread demyelination, without Alzheimer disease (AD) pathology. Methods and results: Initial neuropsychometric evaluation suggested amnestic mild cognitive impairment (aMCI). Serial magnetic resonance images (MRI) images demonstrated the rate of increase in her ventricular volume was comparable to that of 46 subjects with aMCI who progressed to ADem, without accumulating white matter disease. Myelin immunohistochemistry at autopsy demonstrated extensive cortical subpial demyelination. Subpial lesions involved the upper cortical layers, and often extended through the entire width of the cortex. Conclusions: Multiple sclerosis (MS) can cause severe cortical dysfunction and mimic ADem. Cortical demyelination is not well detected by standard imaging modalities and may not be detected on autopsy without myelin immunohistochemistry.

ObjectiveTo determine the proportion of patients who would have an unsuccessful lumbar puncture (LP) due to commonly used LP needles being too short.MethodsThree hundred consecutive adults (age 16–99, mean age 56) who underwent abdominal CT over a 6‐month period were identified. The distance from the skin to the midpoint of the spinal canal was measured in the axial plane, at the level of the iliac crest. This was compared to the length of commonly used spinal needles (88 mm) to assess the number of patients who would have an unsuccessful LP due to this distance being greater than 88 mm from the skin.ResultsIn 72/300 (24%) patients, the midpoint of the spinal canal was greater than 88 mm from the skin. A total of 54/72 (75%) of those patients were female. Of the female participants, 54/159 (34%) had the midpoint of their spinal canal at a distance of greater than 88 mm from the skin. In the male patients, only 18/141 (13%) had a similar finding.ConclusionThis is the first high‐quality study to demonstrate that 24% of the population will have an unsuccessful LP procedure if commonly available spinal needles. We demonstrated that 34% of female patients would have an unsuccessful procedure while, in contrast, a successful LP should be possible in 87% of male patients.