Medical imaging technology plays a crucial role in clinical diagnosis and treatment. Image compression technology provides robust technical support for the storage and transmission of massive medical imaging data, serving as an effective safeguard for hospital data backup and telemedicine. The technology holds broad application prospects in the medical field, enabling the processing of various imaging modalities, multidimensional imaging, and medical video imaging. This study elaborates on general image and video compression algorithms, the application of compression algorithms in the medical field, and the performance metrics of medical image compression, thereby providing critical technical support for enhancing clinical diagnostic efficiency and data management security.

Objective To achieve efficient compression of on-board radiotherapy projection images using dynamic video encoding algorithms.Methods The on-board radiotherapy imaging system primarily provides 2D X-ray projection images for patient positioning verification and 3D tomographic image reconstruction.Since multiple projection images acquired continuously exhibit strong spatiotemporal correlations,their similarities could be used to eliminate redundant information,thereby improving the image compression ratio.During image compression,the image sets obtained at different times were arranged into an image sequence which was input into a video encoder and output as a video file.During image decompression,the video file was input into a video decoder and output as an image sequence,and the images in the sequence were then assigned back to their original image sets.Three current dynamic video encoding algorithms(AVC,HEVC,and AV1)and the classic static image coding algorithm(JPEG 2000)were tested on a database of 2D projection images.The performance of various compression algorithms was evaluated using indicators such as compression ratio(CR),peak signal-to-noise ratio(PSNR),and structural similarity(SSIM).Moreover,visual comparison of projection images before and after compression was evaluated by clinical radiation oncologists.Results Dynamic video encoding algorithms achieved higher CR than the static image coding algorithm.The average CR of the 3 dynamic video encoding algorithms was as followed:CRAVC=11.50,CRHEVC=30.74,and CRAV1=27.10,while the average CR of the static image coding algorithm(JPEG 2000)was 5.28.For abdominal projection images,well-defined contours and textural details were preserved even when the CR reached 42.37.For head-neck projection images,although mild contour blurring emerged at a CR of 20.71,subsequent evaluation by clinical radiation oncologists confirmed that the reconstructed CBCT images still satisfied clinical requirements.Conclusion These dynamic video encoding algorithms effectively utilize the strong correlation information between multiple projection images,reduce the storage of redundant information,and greatly improve the image CR.

Objective To achieve efficient compression of on-board radiotherapy projection images using dynamic video encoding algorithms.Methods The on-board radiotherapy imaging system primarily provides 2D X-ray projection images for patient positioning verification and 3D tomographic image reconstruction.Since multiple projection images acquired continuously exhibit strong spatiotemporal correlations,their similarities could be used to eliminate redundant information,thereby improving the image compression ratio.During image compression,the image sets obtained at different times were arranged into an image sequence which was input into a video encoder and output as a video file.During image decompression,the video file was input into a video decoder and output as an image sequence,and the images in the sequence were then assigned back to their original image sets.Three current dynamic video encoding algorithms(AVC,HEVC,and AV1)and the classic static image coding algorithm(JPEG 2000)were tested on a database of 2D projection images.The performance of various compression algorithms was evaluated using indicators such as compression ratio(CR),peak signal-to-noise ratio(PSNR),and structural similarity(SSIM).Moreover,visual comparison of projection images before and after compression was evaluated by clinical radiation oncologists.Results Dynamic video encoding algorithms achieved higher CR than the static image coding algorithm.The average CR of the 3 dynamic video encoding algorithms was as followed:CRAVC=11.50,CRHEVC=30.74,and CRAV1=27.10,while the average CR of the static image coding algorithm(JPEG 2000)was 5.28.For abdominal projection images,well-defined contours and textural details were preserved even when the CR reached 42.37.For head-neck projection images,although mild contour blurring emerged at a CR of 20.71,subsequent evaluation by clinical radiation oncologists confirmed that the reconstructed CBCT images still satisfied clinical requirements.Conclusion These dynamic video encoding algorithms effectively utilize the strong correlation information between multiple projection images,reduce the storage of redundant information,and greatly improve the image CR.

Objective:To investigate the clinical and pathological features and improve the acknowledgement of intraductal tubulopapillary neoplasm (ITPN) of pancreas.Methods:Six cases with ITPN in the Shandong Provincial Hospital Affiliated to Shandong First Medical University combined with 40 cases from PubMed and CNKI were retrospectively analyzed. There were 25 males and 21 females, aged (58.6±16.0) years. The clinical manifestations, pathological features, treatment and so on were analyzed.Results:All cases were treated with surgery. The main clinical symptoms were upper abdominal pain and discomfort (23 cases, 50.0%), followed by jaundice (9 cases, 19.6%). Seven cases (15.2%) had no clinical symptoms. Three cases (6.5%) had low back discomfort, chills and other rare symptoms, and 4 cases (8.7%) had no clinical symptoms mentioned in the literature. Tumors of 27 cases (58.7%) located in the head of the pancreas, 9 cases (19.6%) in the body and tail, 4 cases (8.7%) in the whole pancreas, 3 cases (6.5%) in the body, 2 cases (4.3%) in ampulla and 1 case (2.2%) in head and body. Most of the tumors located in the main pancreatic duct. Microscopically, back-to-back tubular glands were densely arranged, parts of them with papillary structure, with obvious cell atypia and many mitoses. Twenty-two cases (47.8%) of ITPN were completely confined to the pancreatic duct, and 24 cases (52.2%) were with associated invasive carcinoma. Tumor cells were positive for cytokeratin 7 and mucin 1, but negative for cytokeratin 20, synaptophysin, chromogranin and trypsin. Mucin 2, mucin 5AC and mucin 6 were negative in most cases. Ki-67 ranged from 10% to 70%.Conclusion:Pancreatic ITPNs were mostly located in the pancreatic head, confined to the main pancreatic duct, and were mostly manifested as pain and discomfort in the upper abdomen. Surgery was the main treatment. Tumors cells of ITPN were arranged in tubular and papillary, with severe epithelial atypia and special immunophenotype, parts of cases accompanied with associated invasive carcinoma.

Objective:To observe the clinical and multimodal imaging features of eyes with acute macular neuroretinopathy (AMN) associated with the coronavirus disease 2019 (COVID-19).Methods:A retrospective study. From December 20, 2022 to January 17, 2023, a total of 29 patients (58 eyes) with COVID-19-associated AMN admitted to Department of Ophthalmology of Eye and ENT Hospital, Shanghai Medical College were included in the study. All the affected eyes underwent the best corrected visual acuity, color fundus photography, infrared fundus photography (IR), short-wavelength autofluorescence (SW-AF), near-infrared autofluorescence (NIL-AF), optical coherence tomography (OCT), and OCT angiography (OCTA). All patients were administered microcirculation-improving oral medication with 12 cases receiving adjunctive low-dose corticosteroid therapy. Follow-ups were conducted 1 to 3 months after the initial diagnosis, with a total of 19 cases (38 eyes) completing the one-month follow-up.Results:Out of the 29 cases, there were 9 males (18 eyes) and 20 females (40 eyes), all of whom experienced bilateral eye involvement. The age of the patients ranged from 12 to 47 years, with an average age of (29.9±9.5) years. The time from the onset of fever to the appearance of ocular symptoms was (2.52±2.01) days. Among the 58 affected eyes, there were 5 cases with retinal cotton wool spots, 2 cases with optic disc edema, and 1 case with parafoveal branch retinal vein occlusion. All affected eyes exhibited deep reddish-brown macular dark spots. IR revealed wedge-shaped, wedge-like, or "petaloid-like" dark areas involving the fovea and parafovea. SW-AF examination showed no obvious abnormality in 39 eyes. Weak autofluorescence dark area were consistent with IR in 19 eyes. NIR-AF examination showed spot-like or flaky self-fluorescent dark areas. OCT examination showed strong reflex lesions spreading vertically upward from the retinal pigment epithelium (RPE) layer in the macular area in the acute stage, showing typical "bean seedling" sign. OCTA revealed reduced blood flow density in the deep capillary plexus (DCP) of 50 eyes. Enface OCT displayed lesion areas that corresponded to the dark areas seen in IR. One month after the initial diagnosis, the condition improved in 18 eyes (47.4%, 18/38). Among the 5 eyes with cotton wool spots, regression of these spots was accompanied by loss of nerve fiber layer in 4 eyes. In cases with optic disc edema, the edema subsided. The "bean sprout" sign disappeared in all affected eyes, and the lesions became localized. The ellipsoid zone and/or interdigitation zone in the lesion areas were discontinuous.Conclusions:COVID-19-related AMN is characterized by distinctive features. IR fundus reveals wedge-shaped, wedge-like, or petaloid dark areas involving the fovea and parafovea. OCT displays strongly reflective lesions with vertical spread above the RPE. OCTA shows reduced blood flow density in the DCP of the retina.

Male guinea pigs were exposed to 750ppm or l000ppm or 1 500ppm toluene (8h/d, for 14d), and their hearing thresholds were tested by means of Madsen ERA 2250 system 3d and 14d after exposure. Hearing impairment was observed in all groups. The degree of impairment was related to the exposure concentration and had a tendency to further damage in two weeks. The results indicate that toluene can cause acute hearing impairment even if its concentration is as low as 750ppm and the impairment develops from bad to worse at least in two weeks.

Objective:[WT5BZ] The effects of exogenous vitamin C (VC) and glutathione (GSH) on ultraweak spontaneous luminescence of culturing pulmonary alveolus macrophages from rabbits were studiesd. [WT5FZ]Methods:[WT5BZ] In a special thermostat, which was passed through by airs with various concentrations of oxygen, the alveolar macrophages (AMs) were cultured in DMEM medium with VC or GSH, and the spontaneous luminescence of culturing AMs was examined by a luminometer. [WT5FZ]Results:[WT5BZ] when VC in medium was over 0.3 mmol/L, it could significantly enhance the oxidative luminescence of cells exposed to O 2 and cell death was resulted. However, when the cells were exposed to air without O 2 there was no significant effect. On the contrary,the lower concentration of VC (0.03 mmol/L) as well as GSH could reduce the spontaneous luminescence of cells exposed to a high concentration (99.1%) of O 2 in air. [WT5FZ]Conclusion:[WT5BZ] The results show that the spontaneous oxidation of culturing cells is an important reason for the ultraweak luminescence. High concentration of VC can promote cellular oxidative damage in vitro, but the exogenous GSH has a protective effect against oxidization in culturing cells.