Reduced Field of View APT Imaging of Rectum (RAPTOR) at 3T MRI Scanner / 生物化学与生物物理进展

ObjectiveThe chemical exchange saturation transfer (CEST) technique has become a valuable tool in diagnosing metabolic changes associated with cerebral and systemic diseases, leveraging the calculation of compounds with exchangeable protons in proximity to water molecules. Specifically, the amide proton transfer (APT) CEST technique has shown promise in diagnosing cerebral strokes and tumors by comparing altered endogenous proteins or peptides with normal tissues. Reduced field of view (rFOV) imaging technology has been widely used in the diagnosis of small organ lesions in the body. In this study, we aim to apply the rFOV imaging to identify CEST signals in the rectum, investigating the potential utility of rFOV technique in clinical diagnosis of rectal diseases and providing metabolic insights for chemoradiotherapy. MethodsMRI images of eleven healthy volunteers were acquired using transverse Full_FOV and rFOV CEST imaging on a 3T scanner. The resolution was set at 2.5×2.5×6 mm³ and 1.5×1.5×6 mm³ for Full_FOV or the rFOV method. Saturation powers of 0.7 μT and 2 μT were applied. For the 2 μT saturation, MTRasym at ±3.5 ppm was employed, while for 0.7 μT saturation, Lorentzian difference was used for CEST quantification of the contrast maps and curves. ResultsThe rFOV method has the advantage of halving the scan time while maintaining the same contrast as the Full_FOV method. When compared to Full_FOV methods, rFOV methods exhibited nearly identical Z_spec and very similar MTRasym curves. Additionally, rFOV with a 1.5 mm×1.5 mm in-plane resolution could be achieved in approximately 3 min. rFOV method displayed better structural details for the entire rectum, including CEST contrast maps and quantitative curves. ConclusionCEST MRI proves valuable in diagnosing rectal diseases, and employing the rFOV technique could provide higher spatial and temporal resolution. CEST MRI should be the preferred choice for offering improved diagnostic capabilities with its potential for rectal disease diagnosis.

Opinions about diagnosis and treatment of multilevel cervical spondylotic myelopathy / 中国骨伤

There should be confusion about diagnosis and treatment for multiple segments cervical myelopathy in some respects. The author reviewed the literature and combined with clinical experience, proposed a new classification for cervical myelopathy according to responsibility segment areas, which dividing into single segment,double segments (continues or jumping type), multi-segment (≥ three segments). The responsible segments determination is the premise of diagnosis and also a key to determine surgical decompression segment. Decompression only according to imaging was not desirable, surgical segment should mainly relies on clinical, imaging, electrophysiological and comprehensive analysis to avoid surgery range expansion. Surgical approach and procedures are still the focus and hotspot of cervical myelopathy treatment, and no treatment standards and corresponding guidelines to consult. The author proposes that surgical approach should advocate the individual, and surgical procedure should follow simple instead of complicate, anterior and posterior combined decompression is not necessary in most cases, and anterior and posterior fixation are not need.

An experimental study on the combination of chondroitin sulfate with glycerin for the cryopreservation of corneal graft / 中华实验眼科杂志

BackgroundChondroitin sulfate(CS) is a highly viscous and elastic acid mucopolysaccharide extracted from animal soft tissues,with a wide range of biological activity for use in clinical ophthalmology.Interim preservation solution containing CS has a significant protective effect on corneal endothelial cells (CECs).However,the protective effect played by CS in long-term glycerol cryopreservation of CECs remains to be studied.Objective This study is mainly attempted to investigate the protective effect of CS on graft CECs after cryopreservation by glycerin,and to compare the preserving outcome with that of sodium hyaluronate (SH).MethodsOne hundred and four eyes of fifty-two female Wistar rats were divided into four groups randomly.The cornea grafts were evenly anointed on the surface of the endothelium by 3％ CS and 1％ SH,respectively,and then cryopreserved in glycerol in the 3％ CS group and 1％ SH group,and the corneas cryopreserved only in glycerin were assigned to the glycerin only group.The fresh corneas of matched rats were used as the normal control group.Ninety-six female SD rats were appointed as recipients to receive allogeneic penetrating keratoplasty (PKP) 2 months after the graft cryopreservation.The viability of CECs on the corneas cryopreserved for 20 days and grafts of 14 days following surgery was assessed using trypan blue & alizarin red stain.The ultrastructure of cryopreserved corneas was examined under a transmission electron microscope.The rejection index (RI) and graft survival time were evaluated by inflammatory scoring under the slit lamp 1 day after operation,and regular pathological examination was performed after 7,14 or 30 days.The expression of transforming growth factor-β1 ( TGF-β1 ) and intercellular adhesion molecule-1 ( ICAM-1 ) in corneas and grafts were detected by immunochemistry.ResultsCECs morphology was normal in fresh cornea in normal control group,presenting no blue stained cells after trypan blue staining.In the 3％ CS group,few blue-stained cells were seen:however,the number of blue-stained cells noticeably increased in the 1％ SH group and glycerin only group.The viability and density of CECs were significantly lower in the 1％ SH group and glycerin only group,compared with the 3％ CS group (P＜0.05).Edema of the endoplasmic reticulum,inflammatory infiltration and neovascularization were more severe in the 1％ SH group and glycerin only group than the 3％ CS group 14 days after PKP.Compared with the 1％ SH group and glycerin only group,the R1 of the 3％ CS group was significantly reduced and the CECs survival time was delayed after PKP ( P＜0.05 ).Immunochemistry revealed that the expression of TGF-β1 in grafts (A value)was up-regulated and that of ICAM-1 was down-regulated in the 3％ CS group,compared with the 1％ SH group and glycerin only group ( P＜0.05).ConclusionsThe combination of 3％ CS with glycerol to cryopreserve corneal donor can maintain the viability of CECs for a longer duration and improve the effectiveness of PKP.