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 investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application.Methods:This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis.Results:The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group ( χ2=5.560, P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group ( χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion:SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

Objective:To investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application.Methods:This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis.Results:The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group ( χ2=5.560, P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group ( χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion:SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

Purpose: This retrospective study aimed to evaluate the distribution pattern and prognostic value of 21-gene recurrence score (RS) in Chinese patients with mucinous breast cancer (MC) and compared with infiltrating ductal carcinoma (IDC). Materials and Methods: Patients diagnosed with MC or IDC from January 2010 to January 2017 were retrospectively recruited. Reverse transcriptase–polymerase chain reaction assay of 21 genes was conducted to calculate the RS. Univariate and multivariate analyses were performed to assess the association between RS and clinicopathological factors. Survival outcomes including disease-free survival (DFS) and overall survival (OS) were estimated by Kaplan-Meier method and compared by log-rank test. Results: The MC cohort included 128 patients and the IDC cohort included 707 patients. The proportions of patients with a low (RS < 18), intermediate (18-30), or high risk (RS > 30) were 32.0%, 48.4%, and 19.5% in MC cohort, and 26.9%, 46.8% and 26.3% in IDC cohort. The distribution of RS varied significantly according to different Ki-67 index and molecular subtype in both cohorts. Moreover, the receipt of chemotherapy was associated with RS in both cohorts. Among patients with MC, tumor stage was related to the DFS (p=0.040). No significant differences in DFS and OS were found among MC patients in different RS risk groups (OS, p=0.695; DFS, p=0.926). Conclusion RS was significantly related to Ki-67 index and molecular subtypes in MC patients, which is similar in IDC patients. However, RS was not able to predict DFS and OS in patients with MC.

Objective: To investigate the dosimetric characteristics of conventional two-dimensional radiotherapy of the chest wall, supra-and infra-clavicular regions, and the incidental irradiation dosage of the internal mammary region after modified mastectomy in breast cancer patients. Methods: Clinical data of 20 breast cancer patients including 10 left and 10 right cases who received radiotherapy after modified mastectomy between 2015 and 2016 were retrospectively analyzed. All patients received irradiation to the chest wall, supra-and infraclavicular regions at a prescription dose of 43.5 Gy in 15 fractions with conventional technique. One anterior-posterior (AP) photon field irradiation was delivered for the supra-and infra-clavicular regions, and one electron field for the chest wall. The supra-and infraclavicular regions were re-planned by using two AP/PA fields and the doses of organ at risk were evaluated. Results: With conventional radiotherapy, the D₉₀ of the supra-and infra-clavicular regions were more than 39.15 Gy (EQD₂≥45 Gy) in 17 patients (85%), and the median D₉₀ of the chest wall was 35.38 Gy. The median dose of incidental internal mammary region was 13.65 Gy. Patients with lower body mass index (BMI) received higher D₉₀ in both supra-and infra-clavicular and chest wall irradiation (P=0.039, 0.347). Conclusions Irradiation at D₉₀ of 39.15 Gy to the supra-and infra-clavicular regions with AP/PA fields can meet the prescription dose requirement of ≥90% in most cases and does not increase the irradiation dose to normal tissues. The dose distribution of one electron field of the chest wall is poor. Incidental internal mammary region can be irradiated at a limited dosage. BMI is an influencing factor for dose distribution.

Objective To evaluate the effect of the thickness and area of the cavity between bolus and skin upon the dose deposition in the shallow tissues.Methods The linear accelerator head model of 6 MV X ray was constructed using Geant4,which simulated the accelerator working condition of 10 cm× 10 cm field and recorded the information of emergent particles as phase space file.A water phantom of 30 × 30 × 30 cm3 was designed at the SAD level.A 30 cm × 30 cm × 1 cm water film was constructed adjacent to or with different cavities to the upper surface of the phantom.The phase space file was utilized as particle source to simulate the particle transport process.The axis depth dose distribution and lateral dose profiles in the center area of the field at a depth of 1 mm,5 mm,9 mm,15 mm and 21 mm of the phantom were obtained,respectively.The simulated data obtained from water film with different cavities were compared with those of adjacent to the water phantom.Results When the cavity was ≤ 5 mm,the cavity exerted slight effect.When the thickness was increased,the maximum dose depth (Dmax) was increased,the PDD at Dmax (PD Dmax) became less,the depth of influenced lateral dose profiles was increased and the dose in the center area was decreased.Along with the increase of cavity area,the Dmax was initially increased and then decreased,the PD Dmax was at first decreased and subsequently increased,the depth of influenced lateral dose profile was initially increased and then decreased,the dose in the center area was first decreased and subsequently increased.The lateral dose profile distant from the cavity or located at a depth ≥ 15 mm was almost not affected by the cavity.Conclusion The thickness of the cavity between bolus and skin should be less than 5 mm and the cavity area should be small as possible.

Objective To investigate the effect of cavity thickness, area and distance under the bolus upon the dose in the superficial tissues. Methods An accelerator model was constructed based on Geant4.The model accuracy was validated by the comparison of the calculated data with the measured data. A 30×30×30 cm3 water phantom with the upper surface located at the isocenter level and a 30×30×1 cm3 water film were constructed. Different models with the water film close to or different cavities with the water phantom were established. Under the 10×10 cm2 field with 6 MV X-ray beam,the central axis depth dose distribution and the lateral dose profiles at a depth of 0. 1 cm ( profile1) of the models with different cavities were calculated. The calculated data of different model with the water film close to or different cavities with the water phantom were statistically compared. Results When the cavity thickness was ≤ 0. 5 cm, the cavity exerted slight effect upon the depth of maximum dose ( Dmax ) and superficial dose. As the cavity thickness was increased,the Dmax was also increased,the PDD at 0. 1 cm ( PDD1) was decreased rapidly and the profile1 was increased from the cavity center to the edge. Along with the increase of cavity area,the Dmax was initially increased and then decreased,whereas the PDD1 was first decreased followed by an increase. When the cavity area was small,the profile1 was gradually increased from the cavity center to the edge. When the cavity area was large,the profile1 was initially decreased and subsequently increased. When the distance was ≥0. 2 cm,it was qualified for the clinical requirement and it exerted no effect when the distance was≥1. 0 cm. The profile1 distant from the cavity was not affected. Conclusion The cavity under the bolus should be minimized to reduce the cavity thickness,area and distance as possible.

Objective To investigate the mutations of IDH1,IDH2,p53 gene,and Ki-67 protein expression in different grade of gliomas and identify the association with its clinical relevance. Methods The mutations of IDH1,IDH2 and p53 gene were detected by direct DNA sequencing,and protein expression of Ki-67 was analyzed by immunohistochemistry. The correlations between gender,age,tumor site,differentiation degree and pathological type of patients were analyzed. Results R132H mutation of IDH1 gene was detected in 32.6% samples (14/46 cases),of which the proportion of WHO classification grade Ⅱ was 40.0%,and grade Ⅲ was 58.3%. IDH1 mutations were shown correlated with age,pathology level Ⅱ-Ⅲ,and Ki-67 low expression. p53 mutations were detected in 4 glioblastomas,with mutations located at exon 7,8. IDH1 gene mutation was negatively correlated with Ki-67 expression. Conclusions The proportion of IDH1 gene mutation in different pathological types of gliomas is different,which is the highest in gradeⅡ~Ⅲ. It is suggested that the subtypes should be listed independently by routine tests. Mutations in p53 gene are more common in primary glioblastomas and may be associated with adverse outcomes. The combined detection of DH1,p53 and Ki-67 is conducive to the diagnosis and prognosis of glioma.

Objective To explore a new gradient descent based optimization algorithm in order to improve the efficiency and unrepeatability of current VMAT planning systems.Methods Firstly,fast monotonic descent method was used to generate intensity maps of a simple IMRT plan consisting of few static fields.Then,leaf sequencing algorithm was employed to determine the best segments (aperture shape and weight) of these fields.The segments of the existing beams were fixed,and the new beams were continuously added to the plan and optimized until the maximal number of beams arrived.The performance of this algorithm was evaluated with clinical cases.Results For the head-and-neck case,the computation time was about 5 min while the time for those commercial planning systems was 10-20 min.Due to the nature of gradient-based algorithm,the repeatability of optimization result was guaranteed.The conformity and homogeneity of VMAT plan was better than that of IMRT plan.For most of critical organs,the dose sparing of VMAT plan was better than that of IMRT plan.Conclusions Compared to existing VMAT optimization algorithms,the computation time of our algorithm is significantly reduced and the optimization result is repeatable.

Objective To compare target dosimetric distribution and normal tissue radiation between different static intensity?modulated radiation therapy ( IMRT) plans and volumetric modulated arc therapy ( VMAT) and to identify the best IMRT plan for patients with primary mediastinal B?cell lymphoma ( PMBCL) . Methods A total of 16 patients ( 8 males and 8 females) with early?stage ( Ann?Arbor stageⅠ) PMBCL were enrolled in this study,with doses of 45 Gy for primary gross tumor volume ( PGTV) and 40 Gy for planning target volume (PTV).Four plans were designed for each patient,consisting of static IMRT (5F?IMRT,7F?IMRT,9F?IMRT) and VMAT,and the target dosimetric distribution,normal tissue radiation dose,and efficiency of each plan were evaluated. The difference of dose was analyzed by analysis of variance. Results The mean conformity index ( CI) and homogeneity index ( HI) for PGTV in 5F?,7F?,9F?IMRT and VMAT were 1. 01 and 1. 10, 1. 01 and 1. 10, 1. 01 and 1. 10, and 1. 01 and 1. 11 ( P= 0. 963 and 0. 843) ,respectively,while these two indices for PTV were 1. 04 and 1. 22,1. 03 and 1. 19,1. 03 and 1. 17, and 1. 08 and 1. 14( P=0. 964 and 0. 969) ,respectively. The parameters of volume and dose were similar on normal tissue ( P= 0. 192?1. 000 ) . The treatment time and number of monitor units in 9F?IMRT were significantly higher than those in other static IMRT plans and VMAT ( P=0. 000,0. 000) ,and among these plans,VMAT had the lowest number of monitor units ( 13 345. 0 MU) and the shortest treatment time ( 5. 9 min) . Conclusions The target volume coverage of 7F?and 9F?IMRT is better than that of 5F?IMRT and VMAT.For early?stage PMBCL,VMAT is not superior to IMRT in terms of dosimetry,especially with a larger area of low?dose radiation to the breast,but it is highly efficient in practice.