ObjectiveTo conduct a meta-analysis comparing the accuracy of artificial intelligence (AI)-assisted diagnostic systems based on 18F-fluorodeoxyglucose PET/CT (18F-FDG PET/CT) and structural MRI (sMRI) in the diagnosis of Alzheimer's disease (AD). MethodsOriginal studies dedicated to the development or validation of AI-assisted diagnostic systems based on 18F-FDG PET/CT or sMRI for AD diagnosis were retrieved from the Web of Science, PubMed, and Embase databases. Studies meeting the inclusion criteria were collected, and the risk of bias and clinical applicability of the included studies were assessed using the PROBAST checklist. The pooled sensitivity, specificity, and area under the summary receiver operating characteristic (SROC) curve (AUC) were calculated using a bivariate random-effects model. ResultsTwenty-six studies met the inclusion criteria, yielding a total of 38 2×2 contingency tables related to diagnostic performance. Specifically, 24 contingency tables were based on 18F-FDG PET/CT to distinguish AD patients from normal cognitive (NC) controls, and 14 contingency tables were based on sMRI for the same purpose. The meta-analysis results showed that for 18F-FDG PET/CT, the AI-assisted diagnostic systems had a pooled sensitivity, specificity, and SROC-AUC of 89% (95%CI 88% to 91%), 93% (95%CI 91% to 94%), and 0.96 (95%CI 0.93 to 0.97), respectively. For sMRI, the AI-assisted diagnostic systems had a pooled sensitivity, specificity, and SROC-AUC of 88% (95%CI 85% to 90%), 90% (95%CI 87% to 92%), and 0.94 (95%CI 0.92 to 0.96), respectively. ConclusionAI-assisted diagnostic systems based on either 18F-FDG PET/CT or sMRI demonstrated similar performance in the diagnosis of AD, with both showing high accuracy.
Objective To investigate the relationships between the bony structures, nerve, and indentations of ligamentum flavum of the upper lumbar spine by using CT three-dimensional reconstruction technique, in order to guide the unilateral biportal endoscopy (UBE) technique via contralateral approach in the treatment of upper lumbar disc herniation (ULDH). Methods Twenty-one ULDH patients who were admitted between June 2019 and July 2021 and met the selection criteria were selected as the research subjects. There were 12 males and 9 females with an average age of 62.1 years (range, 55-72 years). The disease duration was 1-12 years (mean, 5.7 years). There was 1 case of L1, 2, 4 cases of L2, 3, and 16 cases of L3, 4. The CT myelography data of T12-S3 segment was saved in DICOM format and imported into Mimics21.0 software for three-dimensional reconstruction. The relationship between the intersection (point Q) of spinous process and the inferior margin of lamina, the indentation of superior margin of ligamentum flavum, the inferior margin of nerve root origin, intervertebral space, and foramen were observed. The Mimics21.0 software was used to create a 3-mm-diameter cylinder to simulate the UBE channel and measure its abduction angle (∠b1), as well as measure the following lumbar vertebra-related indicators: in L1,2-L3,4 segments, the vertical distance from the point Q to the inferior margin of the contralateral lumbar pedicle of the same lumbar vertebra (a1), the superior margin of the contralateral pedicle of the lower lumbar vertebra (a2), the lower endplate of the same lumbar vertebra (a3), the upper endplate of the lower lumbar vertebra (a4); the vertical distance from the lower endplate of lumbar vertebra to the inferior margin of the lumbar pedicle (c1), the vertical distance from the upper endplate of the lower lumbar vertebra to the superior margin of the lumbar pedicle (c2); the vertical distance from the inferior margin of the nerve root origin to the superior margin (d1) and the inferior margin (d2) of the lumbar pedicle, respectively; the vertical distance from the intersection (point P) of the indentation of superior margin of ligamentum flavum and the medial margin of the lumbar pedicle to the superior margin (e1) and the inferior margin (e2) of the lumbar pedicle, respectively; the horizontal distance from the lateral margin of the dural mater (f1) and the narrowest part of the lumbar isthmus (f2) to the facet joint space, respectively. Thirteen of the patients included in the study chose the UBE surgery via contralateral approach. There were 8 males and 5 females with an average age of 63.3 years (range, 55-71 years). The disease duration was 2-12 years, with an average of 6.2 years. There were 3 cases of L2, 3 and 10 cases of L3, 4. The perioperative complications and surgical decompression were recorded. And the effectiveness were evaluated by visual analogue scale (VAS) score, Oswestry disability index (ODI), and short form-36 health survey (SF-36) score. Results The imaging results showed that there was no significant difference in a1, a3, a4, e1, e2, f1, and f2 between segments (P>0.05), and there were significant differences (P<0.05) in a2 and c2 between L1, 2 and L3, 4 segments, in ∠b1 and d2 between L1, 2, L2, 3 segments and L3, 4 segments, and in c1 and d1 between L1, 2 and L2, 3, L3, 4 segments. The 87.30% (110/126) of point Q of L1, 2-L3, 4 segments corresponded to the inferior articular process, and 78.57% (99/126) of the lower endplate corresponded to the level of the isthmus. All 13 patients completed the UBE surgery via contralateral approach, and none were converted to open surgery. All patients were followed up 12-17 months (mean, 14.6) months. The VAS score of low back pain and leg pain, ODI, and SF-36 score at 6 and 12 months after operation significantly improved when compared with those before operation (P<0.05), and further improved at 12 months after operation when compared with 6 months after operation (P<0.05). The imaging review results showed that the herniated disc was removed and the dura mater was decompressed adequately. Conclusion The point Q, the superior margin of ligamentum flavum, and lumbar pedicle can be used as the markers for the treatment of ULBD with UBE surgery via contralateral approach, making the procedure safer, more precise, and more effective.