Regional Cerebral Blood-Flow with 99mTc-ECD Brain Perfusion SPECT in Landau-Kleffner Syndrome: Report of Two Cases

Objective: Technetium-99m ethyl cysteinate dimer (99mTc ECD) single photon emission computed tomography (SPECT) of the brain was used to detect abnormal regional cerebral blood flow (rCBF) in patients with primary Sjögren's syndrome (pSS) and normal findings on brain magnetic resonance imaging (MRI). Methods: 99mTc ECD brain SPECT was performed to detect brain lesions showing hypoperfusion in 32 female patients with pSS and definite neuropsychiatric symptoms or signs. Seventeen female patients with pSS without neuropsychiatric symptoms and signs were included as a control group for comparison. All of the 49 patients with pSS had normal findings on brain MRI. Results: 99mTc ECD brain SPECT showed brain regions with hypoperfusion in 18 (56.3%) of the 32 patients, and parietal lobes were the most common areas with such lesions. By contrast, 99mTc ECD brain SPECT showed brain regions with hypoperfusion in only three (17.6%) of the 17 patients with pSS without neuropsychiatric symptoms or signs. Conclusion: This study suggests that 99mTc ECD SPECT is a sensitive tool for detecting regions of hypoperfusion in the brains of patients with pSS and neuropsychiatric symptoms or signs and normal findings on brain MRI. However, a review of the literature showed that the 99mTc ECD SPECT findings in patients with pSS were non-specific

Association of regional cerebral perfusion impairment with gait and balance performance in dizzy patients using brain perfusion spect: Voxel-based analysis of a pilot sample

Objective(s): The purpose of this study was to investigate regional cerebral blood flow (rCBF) reduction in patients with dizziness and perfusion-related clinical impairment using brain perfusion single photon emission tomography (SPECT). Methods: Thirty-four patients with subjective dizziness and 13 age-and sexmatched healthy controls were studied. Dizziness-related impairments were assessed using the Dizziness Handicap Inventory (DHI) and Short Physical Performance Battery (SPPB). Brain perfusion SPECT scan was acquired from all participants. The carotid intima-media thickness (CIMT) was also measured. Brain perfusion data were qualitatively interpreted in all cases. Voxel-wise analysis was also conducted in 11 patients compared to healthy controls. Results: Thirty-four patients (mean age=53.8±13.4 years, m/f: 19/15) and 13 ageand sex-matched controls (mean age=51.5±13.1, m/f: 7/6) were included. The dizziness severity was mild in 58.8% (n=20), moderate in 26.5% (n=9), and severe in 14.7% (n=5). Qualitative interpretation of SPECT images showed normal scans in 4 (11.2%) patients and abnormal scans in 30 (88.2%) patients. Patients with dizziness showed a significantly decreased brain perfusion in the precuneus, cuneus, occipital lobe (superior and inferior parts), frontal lobe (inferior and middle parts), temporal lobe, parietal lobe (inferior and superior parts), cerebellum, insula, and putamen nucleus. Based on both qualitative SPECT interpretation and voxel-wise analysis, perfusion defect had a significant association with the total SPPB score and the scores of two sub-domains (p[removed]0.05) score . Conclusion: The perfusion-and atherosclerosis-related impairments of gait and balance were largely independent of subjective dizziness and dizziness severity. Moreover, this study provided support for contribution of perfusion impairment to the disturbance of gait and balance in older populations along with other pathologic processes. © 2021 mums.ac.ir All rights reserved

Brain perfusion imaging with voxel-based analysis in secondary progressive multiple sclerosis patients with a moderate to severe stage of disease: a boon for the workforce

Background: The present study was carried out to evaluate cerebral perfusion in multiple sclerosis (MS) patients with a moderate to severe stage of disease. Some patients underwent hyperbaric oxygen therapy (HBOT) and brain perfusion between before and after that was compared. Methods: We retrospectively reviewed 25 secondary progressive (SP)-MS patients from the hospital database. Neurological disability evaluated by Expanded Disability Status Scale Score (EDSS). Brain perfusion was performed by (99 m) Tc-labeled bicisate (ECD) brain SPECT and the data were compared using statistical parametric mapping (SPM). In total, 16 patients underwent HBOT. Before HBOT and at the end of 20 sessions of oxygen treatment, 99mTc-ECD brain perfusion single photon emission computed tomography (SPECT) was performed again then the results were evaluated and compared. Brain perfusion was performed by (99 m) Tc-labeled bicisate (ECD) brain SPECT and the data were compared using statistical parametric mapping (SPM). Results: A total of 25 SP-MS patients, 14 females (56 %) and 11 males (44 %) with a mean age of 38.92 ± 11. 28 years included in the study. The mean disease duration was 8.70 ± 5.30 years. Of the 25 patients, 2 (8 %) had a normal SPECT and 23 (92 %) had abnormal brain perfusion SPECT studies. The study showed a significant association between severity of perfusion impairment with disease duration and also with EDSS (P <0.05). There was a significant improvement in pre- and post-treatment perfusion scans (P <0.05), but this did not demonstrate a significant improvement in the clinical subjective and objective evaluation of patients (P >0.05). Conclusions: This study depicted decreased cerebral perfusion in SP-MS patients with a moderate to severe disability score and its association with clinical parameters. Because of its accessibility, rather low price, practical ease, and being objective quantitative information, brain perfusion SPECT can be complementing to other diagnostic modalities such as MRI and clinical examinations in disease surveillance and monitoring. The literature on this important issue is extremely scarce, and follow up studies are required to assess these preliminary results

Automatic stent and catheter marker detection in X-ray fluoroscopy using adaptive thresholding and classification

In this study, we propose a method for marker detection in X-ray fluoroscopy sequences based on adaptive thresholding and classification. Adaptive thresholding yields multiple marker candidates. To remove non-marker areas, 24 specific features are extracted from each extracted patch and four supervised classifiers are trained to differentiate non-marker areas from marker areas. Quantitative evaluation was carried out to assess different classifier performance by calculating accuracy, sensitivity, specificity and precision. SVM outperforms other classifiers based on the mean value for accuracy, specificity and precision with 81.56, 91.94 and 84.21%, respectively

Self-calibration of C-arm imaging system using interventional instruments during an intracranial biplane angiography

PURPOSE: To create an accurate 3D reconstruction of the vascular trees, it is necessary to know the exact geometrical parameters of the angiographic imaging system. Many previous studies used vascular structures to estimate the system’s exact geometry. However, utilizing interventional devices and their relative features may be less challenging, as they are unique in different views. We present a semi-automatic self-calibration approach considering the markers attached to the interventional instruments to estimate the accurate geometry of a biplane X-ray angiography system for neuroradiologic use. METHODS: A novel approach is proposed to detect and segment the markers using machine learning classification, a combination of support vector machine and boosted tree. Then, these markers are considered as reference points to optimize the acquisition geometry iteratively. RESULTS: The method is evaluated on four clinical datasets and three pairs of phantom angiograms. The mean and standard deviation of backprojection error for the catheter or guidewire before and after self-calibration are [Formula: see text]  mm and [Formula: see text]  mm, respectively. The mean and standard deviation of the 3D root-mean-square error (RMSE) for some markers in the phantom reduced from [Formula: see text] to [Formula: see text]  mm. CONCLUSION: A semi-automatic approach to estimate the accurate geometry of the C-arm system was presented. Results show the reduction in the 2D backprojection error as well as the 3D RMSE after using our proposed self-calibration technique. This approach is essential for 3D reconstruction of the vascular trees or post-processing techniques of angiography systems that rely on accurate geometry parameters