Super-pulse thulium fiber laser (hereinafter referred to as thulium laser) has shown broad application prospects in medical research, especially in the treatment of urinary tract stones.Thulium laser has a thin fiber diameter, which reduces the occupation of the working channel and increases the irrigation water flow.Currently, the peak power reaches up to 500 W, the single pulse energy to 6 J, and the frequency to 2000 Hz.The stone-breaking mechanism of thulium laser is photothermal and photomechanical.Different combinations of energy and frequency will significantly affect the volume of stone fragments. "High energy and low frequency" is more suitable for "fragmentation" stone breaking, while "low energy and high frequency" is more suitable for "powderization" stone breaking.Some in vitro experiments have confirmed that thulium laser has higher stone-breaking efficiency, less stone displacement, and more obvious thermal effects compared to holmium laser.Clinically, thulium laser has been applied to ureteroscopic lithotripsy and percutaneous nephrolithotomy., and the stone free rate and safety are relatively high.This article reviews the stone-breaking principles, in vitro experiments, and clinical applications of thulium laser, aiming to provide better theoretical support and practical experience for the development and application of super-pulse thulium fiber laser in the future.

【Objective】 The thermal effects of super-pulsed thulium fiber laser (TFL) at different powers,lithotripsy modes and irrigation rates were studied using a 3D kidney model to simulate ureteral lithotripsy in vivo. 【Methods】 A thermal effect model was established in vitro. Under the same conditions of laboratory temperature and equipment,the temperature around the optical fiber was measured and compared when different optical fiber diameters,powers,lithotripsy modes and irrigation rates were used to simulate lithotripsy by TFL. 【Results】 There was significant difference in the temperature around the optical fiber caused by two fibers with different diameters under the same conditions (P<0.05). Under the same conditions,different lithotripsic modes produced different temperatures,and the temperature of "high energy and low frequency" was lower than that of "low energy and high frequency" (P<0.05). When the power was 10 W and the minimum irrigation rate was 10 mL/min,the plateau temperature did not reach the safety threshold (43 ℃). When the power was 20 W and the minimum irrigation rate was 10 mL/min,the platform temperature exceeded the safety threshold. When the irrigation rate was 20 mL/min,the platform temperature did not reach the safety threshold. 【Conclusion】 In the study of ureteral lithotripsy in vitro,the power,mode,irrigation rate and optical fiber diameter are factors affecting the thermal effects of TFL. No matter what kind of lithotripsy mode and fiber diameter,the temperature around the fiber is safe when the lithotripsy power is ≤10 W and the irrigation rate is ≥10 mL/min;when the lithotripsy power is ≤20 W and the irrigation rate is ≥20 mL/min,the temperature around the fiber is safe.

Objective:To analyze the safety and efficacy of ultrasound-guided needle-perc assisted retrograde intrarenal surgery (RIRS) in the treatment of small but complex renal calculi, and summarize our clinical experience.Methods:The clinical data of 36 patients with small but complicated renal stones treated by ultrasound-guided needle-perc assisted RIRS in Beijing Tsinghua Changgung Hospital from January 2020 to April 2022, were retrospectively analyzed. There were 25 males and 11 females. The average age was (54.7±6.1) years, and the body mass index (BMI) was (26.3±3.1) kg/m 2. The maximum diameter of the calculi was (1.8±0.7) cm. There were 28 patients without renal hydronephrosis before operation, 8 patients with mild to moderate renal hydronephrosis, 4 patients with caliceal diverticular stones, 32 patients with lower pole stones, 10 patients with ureteral stones, 6 patients with previous surgical history of ipsilateral kidney stones, and 3 patients with stones in the solitary kidneys. Patients were placed in oblique supine lithotomy position or prone split leg position (female). For lower pole stones or diverticular stones that were difficult to be handled by flexible ureteroscope, the needle-perc was used to puncture the stones in target calyx under ultrasound guidance. Holmium laser was then used to pulverize or fragment the calculi, and the flexible ureteroscope was used to remove or further pulverize the stone fragments. Perioperative indexes and postoperative complications were recorded, and stone-free rate was analyzed. Results:All 36 cases were successfully operated. The median operation time was 61.5(59.0, 66.8)min, with a median decrease in hemoglobin on the first postoperative day of 1.6(0.8, 2.0)g/ L, a median postoperative hospital stay of 1.5(1.0, 2.0)days, and a median needle-perc tract of 1(1, 2). The complications were recorded in 4 patients (11.1%), all of which were Clavien-Dindo grade I, including postoperative fever in 2 patients and analgesic use in 2 patients. The primary stone-free rate was 83.3% (30/36). The 6 patients with residual stones were treated by external physical vibration lithecbole on the 3rd to 7th day after surgery. After 1 month follow-up, residual stone expulsion were seen in 3 patients. Three patients with residual stones were followed up regularly. The final stone-free rate was 91.7% (33/36).Conclusions:Ultrasound-guided needle-per assisted RIRS is safe and effective in the treatment of small but complex renal calculi, with high postoperative stone free rate and low complication rate.

Objective:To explore the clinical application value of MRI in quantitative evaluation of anterior cruciate ligament mucoid degeneration (ACL-MD).Methods:From March to July 2020, 40 patients who were scheduled to undergo arthroscopic treatment were prospectively collected in the First Affiliated Hospital of Kunming Medical University.The anterior cruciate ligament tissue from the lateral edge of the tibial end was taken during the operation. Based on the pathologicalre sults, the patients were divided into the ACL-MD group ( n=19) and the normal group ( n=21). The sagittal plane three-dimensional steady-state rapid precession (3D-FIESTA), T 1 mapping, T 2 mapping, and T 2* mapping were performed before the knee joint surgery, and the scanned images were post-processed and analyzed to measure the T 1, T 2, and T 2* values of the tibial end of the anterior cruciate ligament.The relaxation time of the ACL-MD group and the normal group was compared using independent sample t test. The ROC curve was drawn using each parameter and the areas under the curve (AUC) for the diagnosis of ACL-MD were obtained.DeLong test was used to compare the differences of AUCs. Results:The T 1 [(1 291.9±273.4) ms], T 2 [(54.8±10.6) ms], and T 2* values [(30.6±6.4) ms] of anterior cruciate ligaments in the ACL-MD group were significantly higher than those in the normal group [ (1 087.0±121.0), (44.8±7.1), (20.4±4.8) ms; t=3.011, 3.473, 5.658, all P<0.001]. The AUCs of T 1, T 2, T 2* were 0.747, 0.764, 0.912, sensitivity of 63.2%, 63.2%, 100%, and the specificity of 100%, 95.2%, 76.2% in diagnosing ACL-MD. The AUC of the T 2* value was higher than those of the T 1 and T 2 values, and the differences were statistically significant ( Z=1.734, 2.162, P=0.043, 0.031). Conclusion:T 1, T 2, T 2*values measured by MRI quantitative imaging have high performance in assessing knee joint ACL-MD, and T 2* value has the largest AUC and the highest diagnostic efficiency.

Liver cancer is a common type of malignant tumor in digestive system. At present, computed tomography (CT) plays an important role in the diagnosis and treatment of liver cancer. Segmentation of tumor lesions based on CT is thus critical in clinical diagnosis and treatment. Due to the limitations of manual segmentation, such as inefficiency and subjectivity, the automatic and accurate segmentation based on advanced computational techniques is becoming more and more popular. In this review, we summarize the research progress of automatic segmentation of liver cancer lesions based on CT scans. By comparing and analyzing the results of experiments, this review evaluate various methods objectively, so that researchers in related fields can better understand the current research progress of liver cancer segmentation based on CT scans.

Objective To establish a clinical scoring system for the prognosis of patients with single large hepatocellular carcinoma (HCC) after hepatectomy.Methods 268 patients with single large HCC who underwent hepatectomy in West China Hospital of Sichuan University from January 2009 to December 2013 were included in this prospective study. There were 227 males and 41 females, of which 198 cases aged≤60 years old, 70 aged>60 years old. The informed consents of all patients were obtained and the local ethical committee approval was received. The patients' survival were observed. The independent risk factors for postoperative prognosis of patients with single large HCC were selected by Cox proportional risk regression mode. Based on the risk factors, the prognostic scoring system for single large HCC wasestablished. The scoring system was tested through survival analysis by Kaplan-Meier and Log-rank test. Results The median overall postoperative survival was 45 months, and the tumor-free survival was 31 months. Platelet-to-lymphocyte ratio (PLR)≥107, tumor diameter≥6.8 cm and positive microvascular invasion (MVI) were the independent risk factors for postoperative overall survival and tumor-free survival in patients with single large HCC (HR=1.004, 1.092, 2.233 and 1.003, 1.062, 1.534; P<0.05). Every independent risk factor was assigned 1 point. All patients were divided into low risk group (0 point), moderate risk group (1-2 points) and high risk group (3 points). The 5-year survival rate of high risk group was 25.4％, and that of moderate and low risk group was 33.2％ and 52.1％ respectively, where significant difference was observed (χ2=23.1, P<0.05). Similar Results were observed when the scoring system was used in patients with or without cirrhosis.Conclusions PLR≥107, tumor diameter≥6.8 cm and positive MVI are the independent risk factors for the prognosis of patients with single large HCC after resection. The prognostic scoring system established in this study can be used to predict the postoperative long-term survival of patients.

Child and adolescent mental disorders are common disorders with various symptoms,and attracting more attention due to the increasing prevalence.Mental disorders,especially the attention-deficit hyperactivity disorder (ADHD) and the autism spectrum disorder (ASD),have great influence on the development of children and adolescents.Nowadays,the biomarkers from neuroimaging such as magnetic resonance imaging (MRI) have a great importance on the diagnosis of mental disorders,and machine learning has been proved to be very powerful in the processing for neuroimages.Nowadays,many researchers are focusing on the studies of computer-aided diagnosis (CAD) based on machine learning and neuroimaging.In this review,the technical details of machine learning based CAD of child and adolescent mental disorders are briefly introduced,and the research progress in CAD of ADHD and ASD based on machine learning and structural MRI are summarized.These studies showed that many machine learning methods have been used in the diagnosis of child and adolescent mental disorders,but the relevant methods cannot be applied to clinical diagnosis.Further studies should be conducted to improve the diagnostic ability of machine learning methods from multiple perspectives,and provide an objective and reliable tool for the clinical diagnosis of child and adolescent mental disorders.

Objective To investigate the diagnosis and treatment of primary presacral tumor. Methods The clinical data of 18 patients with primary presacral tumor were retrospectively analyzed. Results Preoperative diagnosis of primary presacral tumor depended on digital rectal examination, endorectal ultrasound, CT, MRI, et al. The surgical approaches of 18 cases included posterior approach (14 cases) and abdominoperineal approach (4 cases). All tumors were completely resected. Postoperative complications were rectal injury (1 case) and wound infection (2 cases), which were cured by symptomatic treatment. Postoperative pathological results showed that 15 cases had benign lesions and 3 cases had malignant lesions. Sixteen patients were followed up from 0.5 to 5.0 years, with recurrence in 2 cases and death in 2 cases. Conclusions Primary presacral tumor should be treated with operation. Sufficient preoperative examination, personalized operative planning, subtle manipulation operative procedures with an experienced multidisciplinary team, are the important points in preventing or reducing recurrence. Endorectal ultrasound plays an important role in the diagnosis and treatment of primary presacral tumor.

Objective To investigate the value of blood oxygenation level dependent(BOLD)fMRI in assessing the functional changes of the lumbar dorsal extensor muscles before and after exercise in healthy young people.Methods The changes of the R2*value of lumbar dorsal extensor group in 30 healthy young volunteers(15 males and 15 females)before and after exercise was prospectively studied.BOLD-fMRI scans were performed on healthy young volunteers before and after exercise, the exercise mode was to perform the upper body flexion and extension movement with a simple Rome stool.The scanned images were processed and analyzed, the cross-sectional area and R2* value of the lumbar dorsal extensor muscles (including the multifidus,the longissimus and the iliocostalis)were measured at the upper margin of the L3 and L4 vertebral body before and after exercise.The paired t test was used to compare CSA and R2*values of muscles before and after loading. The CSA and R2* value of different muscles in different sides were compared by independent sample t test. Pearson correlation analysis was used to analyze the relevance between CSA and R2* in muscle before and after exercise. Results After exercise, the R2* values of multifidus,longissimus and iliocostalis at the upper margin of the L4 vertebral body were[(39.2±8.6),(38.9± 7.7),(41.6±7.8)]Hz,significantly lower than before exercise[(46.1±6.9),(45.3±6.2),(46.0±6.7)]Hz(P<0.01);the changes of R2*values of the muscles between the left and right sides before and after the movements were not statistically significant(P>0.05).The R2*values of longissimus and iliocostalis at the upper margin of the L3 vertebral body were[(44.2±9.1),(46.6±9.3)]Hz,significantly lower than before exercise[(48.6±7.2),(49.7± 6.8)]Hz (P<0.01), but the R2* values of multifidus after loading was (43.9 ± 9.0)Hz, there was no statistical difference compared with before exercise (46.8 ± 6.6)Hz (P>0.05);there was a significant difference in the changes of R2*value before and after the movement between the left and right side of iliocostalis(P<0.05).A significant negative correlation between CSA and R2*value was found in the iliocostalis on the right side at the upper margin of L3 vertebral body and in the multifidus on the left side at the upper margin of L4 vertebral body,and the correlation coefficients were (-0.697,-0.616).Conclusion BOLD-fMRI can be a new way to assess the functional changes of the lumbar dorsal extensor group before and after exercise.

Objective To compare the efficacy and safety of duloxetine and gabapentin in the treatment of diabetic peripheral neuritis .Methods 135 patients with diabetic peripheral neuritis were divided into the observation group(71 cases) and the control group (64 cases) according to random number table method ,and all patients received hypoglycemic therapy based on diabetes treatment principle .Furthermore,the observation group received oral duloxe-tine,while the control group was given oral gabapentin .The pain scores of all patients were evaluated using visual ana-log scale(VAS) and medical outcomes study (SF-36),and the adverse reactions were recorded during treatment . Results (1) Compared with before treatment ,both VAS scores and SF-36 scores in observation group and control group declined significantly at the end of 1st,2nd,4th week after treatment(all P<0.05),while there were no statis-tically significant differences in VAS scores and SF-36 scores between the two groups at the same time point ( all P>0.05).(2)The incidence rates of dry mouth ,drowsiness,fatigue and dizziness in observation group were significantly lower than those in control group (18.31% vs.34.38%,4.23% vs.26.56%,0.00% vs.23.44%,0.00% vs. 15.63%,χ2 =4.059,13.308,4.059,4.059,all P<0.05),while there were no statistically significant differences in incidence rates of nausea ,diarrhea and flustered between the two groups (all P<0.05).Conclusion The duloxetine and gabapentin in the treatment of diabetic peripheral neuritis have similar efficacy , but the duloxetine has better security.