Crossed cerebellar diaschisis on 18F-FDG PET: Frequency across neurodegenerative syndromes and association with 11C-PIB and 18F-Flortaucipir

We used 18F-FDG-PET to investigate the frequency of crossed cerebellar diaschisis (CCD) in 197 patients with various syndromes associated with neurodegenerative diseases. In a subset of 117 patients, we studied relationships between CCD and cortical asymmetry of Alzheimer’s pathology (β-amyloid (11C-PIB) and tau (18F-Flortaucipir)). PET images were processed using MRIs to derive parametric SUVR images and define regions of interest. Indices of asymmetry were calculated in the cerebral cortex, basal ganglia and cerebellar cortex. Across all patients, cerebellar 18F-FDG asymmetry was associated with reverse asymmetry of 18F-FDG in the cerebral cortex (especially frontal and parietal areas) and basal ganglia. Based on our operational definition (cerebellar asymmetry >3% with contralateral supratentorial hypometabolism), significant CCD was present in 47/197 (24%) patients and was most frequent in corticobasal syndrome and semantic and logopenic variants of primary progressive aphasia. In β-amyloid-positive patients, mediation analyses showed that 18F-Flortaucipir cortical asymmetry was associated with cerebellar 18F-FDG asymmetry, but that cortical 18F-FDG asymmetry mediated this relationship. Analysis of 18F-FDG-SUVR values suggested that CCD might also occur in the absence of frank cerebellar 18F-FDG asymmetry due to symmetrical supratentorial degeneration resulting in a bilateral diaschisis process.

Persistence of Glenohumeral Subluxation is Correlated with Prolonged Existence of Crossed Cerebellar Diaschisis in a Hemiplegic Stroke Survivor: A Pilot Study

Glenohumeral Subluxation (GHS) is one cause of shoulder pain after stroke. The greater the distance of GHS, the higher is the chance of rotator tendonitis or tearing of the tendon, causing limited motions and excruciating pain. Cross Cerebellar Diaschisis (CCD), a reduction of blood flow in the contralateral cerebellum after the supratentorial stroke, is detectable by a brain perfusion scan, and it has marked impacts on functional outcomes after stroke. We presented here a case on hemiplegic stroke. CCD of the patient persisted for 7 months without improvements. The patient underwent measurement of GHS and Single Photon Emission Computed Tomography to confirm the characteristic relationship. The patient’s GHS persisted for a prolonged period of time during which the acromiohumeral distance was longer than those of the general CCD-free stroke. Together with persisted CCD, the persistence of GHS was correlated with a prolonged CCD, which is presumably one sign of motor deficits associated with CCD.

Crossed cerebellar diaschisis after stroke detected noninvasively by arterial spin-labeling MR imaging

Background As a noninvasive perfusion-weighted MRI technique, arterial spin-labeling (ASL) was becoming increasingly used to evaluate cerebral hemodynamics in many studies. The relation between ASL-MRI and crossed cerebellar diaschisis (CCD) was rarely discussed. In this study, the aim of our study was to assess the performance of ASL-MRI in the detection of crossed cerebellar diaschisis after stroke in compared with single-photon emission CT (SPECT). Results 17 of 51(33.3%) patients revealed CCD phenomenon by the SPECT method. In CCD-positive group, CBFASL of ipsilateral cerebellar were significantly increased compared with contralateral cerebellar (p < 0.0001) while no significant differences (p = 0.063, > 0.001) in the CCD-negative group. Positive correlation was detected between admission National institute of health stroke scale (NIHSS) and asymmetry index of SPECT (AISPECT) (r = 0.351, p = 0.011), AIASL (r = 0.372, p = 0.007); infract volume and AISPECT (r = 0.443, p = 0.001), AIASL (r = 0.426, p = 0.002). Significant correlation was also found between cerebral blood flow of SPECT (CBFSPECT) and CBFASL, AISPECT and AIASL (r = 0.204, p = 0.04; r = 0.467, p = 0.001, respectively). Furthermore, the area under the receiver operating characteristic (ROC) curve value of AIASL was 0.829. Conclusions CBF derived from ASL-MRI could be valuable for assessment of CCD in supratentorial stroke patients. Additionally, CCD was significantly associated with larger ischemic volume and higher initial NIHSS score.