ABSTRACT
BACKGROUND:There is no consensus on the optimal bone tunnel position in the lateral clavicle,which guides coracoclavicular ligament reconstruction.Postoperative complications such as enlargement of the lateral clavicle bone tunnel,bone osteolysis,clavicle fracture,and failure of internal fixation are likely to occur.Bone mass density plays an important role in the strength and stability of endophytic fixation.Regional differences in the bone mass density of the distal clavicle should not be overlooked in the repair and reconstruction of acromioclavicular dislocation.Currently,there are no quantitative clinical studies in humans regarding the bone mass density of the distal clavicle. OBJECTIVE:To measure the magnitude of bone mass density in different regions of the distal clavicle by quantitative CT to provide a reference for surgeons to repair and reconstruct the coracoclavicular ligament. METHODS:101 patients undergoing quantitative CT checking in Fuyang People's Hospital Affiliated to Anhui Medical University from October to December 2022 were enrolled,from which 1 616 samples of subdivisional bone mass density of the distal clavicle were measured.For each of the quantitative CT samples,firstly,the distal clavicle was divided medially to laterally into the following four regions:conical nodal region(region A),inter-nodal region(region B),oblique crest region(region C)and distal clavicular region(region D).Secondly,each region was divided into the first half and the second half to determine eight subdivisions,then setting semiautomatic region of interest(ROI)in each subdivision:(ROI A1,A2,B1,B2,C1,C2,D1,and D2).Thirdly,each quantitative CT scan was transferred to the quantitative CT pro analysis workstation,and cancellous bone mass density was measured in the distal clavicle ROI.Finally,the clavicular cortex was avoided when measuring. RESULTS AND CONCLUSION:(1)There was no statistically significant difference in bone mineral density on the different sides of the shoulder(P＞0.05).(2)The analysis of bone mineral density in eight sub-areas of the distal clavicle A1,A2,B1,B2,C1,C2,D1,and D2 showed statistically significant differences(P＜0.05).It could be considered that there were differences in bone mineral density in different areas of the distal clavicle.After pairwise comparison,there was no statistically significant difference in bone mineral density between A1 and A2,D1 and D2,A2 and B1(P＞0.05),and there was a statistically significant difference in bone mineral density between the other sub-areas(P＜0.05).(3)The bone mineral density in the region A2 of the anatomical insertion of the conical ligament was significantly higher than that in the inter-nodular area(region B)(P＜0.05).The bone mineral density in the region A1 was higher than that in the region A2,but the difference was not statistically significant(P＞0.05).The bone mineral density in the region C1 of the anatomical insertion of the trapezium ligament was higher than that in regions C2,D1 and D2,and the bone mineral density in the inter-nodular area(region B)was significantly higher than that in regions C and D(P＜0.05).(4)These results have suggested that there are differences in bone mass density in different regions of the distal clavicle;regional differences in bone mass density in the distal clavicle during repair and reconstruction of acromioclavicular dislocation cannot be ignored.Consideration should be given not only to biomechanical factors but also to the placement of implants or bone tunnels in regions of higher bone mass density,which could improve the strength and stability of implant fixation and reduce the risk of complications such as bone tunnel enlargement,osteolysis,fracture and implant failure.
ABSTRACT
Objective:To explore the optimal acceleration factor and feasibility of the compressed SENSE (CS) technique in non-contrast MR coronary angiography (NMRCA) for clinical practice.Methods:The image data of completed coronary CTA and 3.0 T NMRCA sequence in 31 patients with suspected coronary heart disease were prospectively recruited at Fuyang People′s Hospital from August 2021 to November 2021. NMRCA sequences included conventional SENSE2 sequence and CS sequences with acceleration factors of 4, 5, and 6, respectively. The subjective scores of image quality and the objective scores, the contrast ratios between assessed coronaries and myocardium (CMCR) were compared among the 4 groups using the Friedman and Wilcoxon rank sum test.Results:Compared with the conventional SENSE2 [(343±46)s], the scan time of CS4 (269±36), CS5 (214±29) and CS6 (178±26) s were shortened by 21.5%, 37.5% and 48.0%, respectively. There was a good consistency between the subjective scores of the four groups (Kappa=0.769, 95% Cl 0.738-0.800). There was no significant difference in subjective score and CMCR value between CS4 and SENSE2 ( P>0.05). The coronary artery segments of CS5 and CS6 were significantly different from SENSE2 group ( P<0.05). Conclusions:For 3.0 T NMRCA, CS technology shows high feasibility. The CS4 can reduce imaging time while ensuring high-quality coronary arterial images, which has a well-established clinical application value for NMRCA.
ABSTRACT
Objective: To investigate the feasibility of three dimensional MRI (3D-MRI) based on compressed sensing (CS) in knee joint imaging and its value in assessing meniscal injuries. Methods: Knee MRI were performed on 26 patients with suspected knee injury (injured group) and 30 healthy volunteers (control group). Conventional fat saturation proton density-weighted imaging (fsPDWI) and CS-3D-MRI were collected. The results of arthroscopy of injured group were recorded. MRI of the right knee were obtained in control group, then CS-3D-MRI were reconstructed with 3 different denosing (DS) levels (CS-DSweak, CS-DSmedium, CS-DSstrong), and the sagittal image quality was evaluated subjectively and objectively. Patients in injured group received MRI before arthroscopy. CS-3D-MRI of injured group were reconstructed with CS-DSmedium, and the consistency of CS-3D-MRI diagnostic results with those of arthroscopy was analyzed. Results: For images of control group, there was no statistical difference of the quality scores of reconstructed CS images of different DS levels and fsPDWI (Z=0.35, P=0.32), while statistically significant differences of signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were found in images obtained with 4 different sequences (F=36.01, 9.62, both P0.05). CS-3D-MRI diagnosed meniscus injuries in all patients in injury group, highly consistent with results of arthroscopy (Kappa=0.94, P<0.01). Conclusion: Based on CS technique, 3D-MRI could be used for knee joint imaging, which was able to shorten scanning time on the premise of ensuring image quality, therefore had good value for evaluation on meniscus injuries.