Myelin imaging measures as predictors of cognitive impairment in MS patients: A hybrid PET-MRI study.

BACKGROUND: Cognitive impairment is one of the concerns of Multiple Sclerosis (MS) and has been related to myelin loss. Different neuroimaging methods have been used to quantify myelin and relate it to cognitive dysfunctions, among them Magnetization Transfer Ratio (MTR), Diffusion Tensor Imaging (DTI), and, more recently, Positron Emission Tomography (PET) with 11C-PIB. OBJECTIVE: To investigate different myelin imaging modalities as predictors of cognitive dysfunction. METHODS: Fifty-one MS patients and 24 healthy controls underwent clinical and neuropsychological assessment and MTR, DTI (Axial Diffusion-AD and Fractional Anisotropy-FA maps), and 11C-PIB PET images in a PET/MR hybrid system. RESULTS: MTR and DTI(FA) differed in patients with or without cognitive impairment. There was an association of DTI(FA) and DTI(AD) with cognition and psychomotor speed for progressive MS, and of 11C-PIB uptake and MTR for relapsing-remitting MS. MTR in the Thalamus (ß= -0.51, p = 0.021) and Corpus Callosum (ß= -0.24, p = 0.033) were predictive of cognitive impairment. DTI-FA in the Caudate (ß= -26.93, p = 0.006) presented abnormal predictive result. CONCLUSION: Lower myelin content by 11C-PIB uptake was associated with worse cognitive status. MTR was predictive of cognitive impairment in MS.

Clinical and radiographic evaluation of the shoulder of spinal cord injured patients undergoing rehabilitation program.

STUDY DESIGN: Clinical and radiographic evaluation of the shoulders of tetraplegic and paraplegic patients who attend rehabilitation program. OBJECTIVES: The objective of this study is to establish the usefulness of radiography as a trial exam for shoulder pain in spinal cord injured patients. SETTING: Hospital das Clinicas-UNICAMP. Campinas, Sao Paulo, Brazil. METHODS: Thirty-two shoulders of 16 patients were evaluated by clinical exam and radiography. Patients were divided into two groups: paraplegic and tetraplegic. A control group of 16 normal volunteer subjects was selected. RESULTS: Shoulder pain was reported in 88.89% of tetraplegic and 42.85% of paraplegic. The time of injury ranged from 1.5-22 years (mean 7.88 years); patients had a mean age of 34.68 years (range, 21-57 years). The acromioclavicular joint (ACJ) space ranged from 0.03-0.7 cm on the right side and 0.15-0.7 cm on the left side, with a mean of 0.37 and 0.41 cm, respectively. No correlation was found between shoulder pain and gender, age or time since injury. There was a trend to correlation between shoulder pain and type of injury with tetraplegic having a tendency to pain symptoms. On average, tetraplegic had smaller ACJ. CONCLUSIONS: The small number of patients in this study did not allow us to confirm the hypothesis that X-ray finding may indicate risk for shoulder pain in spinal cord injury patients. A work with a greater number of subjects could demonstrate association between shoulder pain and the reduced acromioclavicular distance, making plain radiography a trial exam for spinal cord-injured patients.