Objective To evaluate the efficacy of proximal percutaneous pedicle screw fixation combined with distal open osteotomy for sagittal plane imbalance of adult spinal deformity.Methods From January 2011 to June 2015,23 patients with diagnosis of adult spinal deformity were treated with proximal percutaneous pedicle screw fixation combined with distal open osteotomy,there were 8 males and 15 females,aged from 52 to 67 years old (average,62.1 years old).The operation time,blood loss,drainage and perioperative complications were recorded;standing anteroposterior and lateral radiographs of the whole spine were taken and the following parameters were measured:sagittal vertical axis (SVA),lumbar lordosis(LL),pelvic tilt (PT),sacral slope (SS),pelvic incidence/lumbar lordosis mismatch (PI-LL),the above parameters were compared between preoperation and postoperation.Oswestry disability index (ODI) was used to evaluate the clinical efficacy.Results The mean operation time was 253.9±52.1 min,the mean blood loss and drainage was 1 258.5±272.2 ml and 725.1 ± 135.2 ml.No patient got infected,died or had deep vein thrombosis.All patients were followed up for an average of 21.2 months (range,13-52 m).The SVA was restored from 12.6±1.4 cm to 3.5±0.7 cm.In addition,LL,SS,PT,and PL-LL were improved from 13.5°±2.3°,13.9°±2.3°,29.7°±9.6°,29.5°±13.7° to 38.8°±9.6°,25.5°±5.8°,18.9°±8.2°,7.1°±3.6°.The ODI score decreased from 40.3％±12.5％ to 13.6％±2.57％ at the time of the last follow-up compared with preoperation.Conclusion Proximal percutaneous pedicle screw fixation combined with distal open osteotomy for sagittal plane imbalance of adult spinal deformity could restore the sagittal balance and improve the quality of life.

Objective To analyze the volume and position of the gross tumor volumes (GTV) in primary esophageal cancer based on contrast-enhanced three-dimensional (3D),four-dimensional (4D) and cone beam (CB) computed tomography (CT).Methods A total of thirty-four patients underwent 3D-CT and 4D-CT simulation scans for computer treatment plan and contrast-enhanced CBCT scans were conducted prior to the first treatment.GTV3D,GTV4D50,internal GTVMIP (IGTVMIP) and internal GTVCBCT (IGTVCBCT) were delineated on 3D-CT,4D-CT50 (the end expiratory phase),4D-CTMIP (the maximum intensity projection),and CBCT datasets,respectively.The IGTV10 was defined as 10 respiratory phases GTVs in 4D-CT.To evaluate the difference in position,volume and the volumes encompassed characteristic.Results The significant difference was observed in the volumes [IGTV10 ＞ (IGTVCBCT or IGTVMIP) ＞ (GTV3D or GTV4D50)] regardless of the tumor location.Regarding IGTV10 as the standard volume,the underestimations or overestimations between IGTV10 and IGTVCBCT were larger than that of between IGTV10 and JGTVMIP (t =-8.294--3.192,P ＜ 0.05).However,there was no significant difference between the areas of IGTV10 which excluded in IGTVCBCT and IGTV3D (P ＞ 0.05).The GTV4D50/ IGTVCBCT ratio for upper esophageal tumors was negatively correlated to motion vector (r =-0.756,P ＜ 0.05).The centroid coordinates of IGTVCBCT in AP direction were significantly different from the test volumes (GTV3D,GTV4D50,IGTVMIP and IGTV10) (t =-3.559--2.435,P ＜ 0.05).The IGTV10/IGTVCBCT ratio was positively correlated to motion vector (r =0.695,P ＜ 0.05) for middle esophageal tumors.The centroid coordinates of IGTVCBCT were significantly different IGTV10 (t =2.201,P ＜0.05) in AP direction.For distal esophageal tumors,the significant difference was observed in the centroid coordinate between IGTVcBcT and IGTVMIP (t =-2.365,P ＜ 0.05) in LR direction.The percentage of IGTV10 excluded the IGTVcBcT were significantly correlated to the motion vector (r =0.540,0.678,P ＜ 0.05) for both middle and distal esophageal tumors.The mean MI value of IGTVCBCT to the other four test volumes ranged from 0.65 to 0.72.Conclusions CBCT has much motion information than 3D-CT but less than IGTV10.CBCT was similar to MIP images based on respiration motion.However,the target motion information encompassed in CBCT and MIP images cannot be exchanged to each other.

Objective To compare the normal thickness of the esophageal wall measured by contrast?enhanced three?dimensional ( 3DCT ) , four?dimensional ( 4DCT ) , and cone beam computed tomography ( CBCT) ,and to provide a basis for target volume delineation in esophageal cancer. Methods From 2009 to 2016,thoracic contrast?enhanced 3DCT and 4DCT simulations were performed in 50 patients with lung cancer or metastatic lung cancer. Contrast?enhanced CBCT scans were acquired during the first three?dimensional conformal radiotherapy. The normal esophageal wall was contoured on 3DCT images, the end?exhalation phase of 4DCT images ( 4DCT50 ) , the maximum intensity projection of 4DCT images (4DCTMIP),and CBCT images. The wall thickness was measured on each segment and the average thickness of esophageal wall was obtained. Comparison of the thickness of a fixed segment of esophageal wall between different CT images was made by paired t test. Comparison of thickness on the same type of CT images between different segments of esophageal wall was made by one?way analysis of variance. Results For the thoracic and intra?abdominal segments,there was no significant difference in the thickness of esophageal wall between 3DCT and 4DCT50 images ( P= 0?056?0?550 );however, the thickness of esophageal wall was significantly smaller on 3DCT images than on 4DCTMIP or CBCT images (P=0?000?0?004).For the upper and middle thoracic segments,the thickness of esophageal wall was significantly larger on CBCT images than on 4DCTMIP images ( P= 0?008, P= 0?001 ) . On 3DCT, 4DCT50 , and 4DCTMIP images, the thickness of esophageal wall was significantly larger in the lower thoracic segment than in the upper or middle thoracic segments ( P=0.008~0?041);the intra?abdominal segment had a significantly larger thickness of esophageal wall than the thoracic segments ( all P=0?000 ) . There was no significant difference in wall thickness on CBCT images between three thoracic segments ( P=0.088~0?945) . Conclusions A uniform criterion can be adopted to judge the normal thickness of esophageal wall in gross tumor volume ( GTV ) delineation on 3DCT and 4DCT50 images for thoracic esophageal cancer. However,caution should be taken when 5 mm is used as a criterion for normal thickness of esophageal wall in GTV delineation on 4DCTMIP and CBCT images.

Acute lung injury after thoracic surgery is the main cause of perioperative death.Acute lung injury is a complex pathophysiological process involving inflammation,characterized by non cardiogenic hypoxemia and acute exudation of the lungs in imaging.Intraoperative ventilation strategy is the most important factor of postoperative acute lung injury.The core of treatment for postoperative acute lung injury is symptomatic support,and prevention is still the most effective strategy for the management of acute lung injury.In this review,the diagnosis,pathogenesis,risk factors and treatment of post-thoracic acute lung injury are introduced,and the progress of prevention strategy and treatment are discussed and summarized.

Objective To assess the effects of axial spinous process-muscle-vascellum complex transplantation for posterior atlantoarial fusion.Methods Data of 27 cases with altantoarial disease who were treated by posterior atlantoarial fusion using axial spinous process-muscle-vascellum complex transplantation from June 2015 to June 2016 were retrospectively analyzed.There were 19 males and 8 females aged from 9 to 68 years old (mean,41.0±15.4 years old).Two cases were diagnosed with atlanto-axial instability.Fourteen cases were diagnosed with atlas fracture and eleven cases were diagnosed atlanto-axial fracture.All the 27 patients suffered from neck pain or limitations of cervical motion.All patients were assessed clinically by atlantoaxial reduction and bone graft fusion.The pre-operative and post-operative atlanto-dens interval (ADI),visual analogue scale (VAS),Japanese Orthopaedic Association scores (JOA),improvement rate of JOA score and axial symptoms were measured and statistically analyzed.Complications were recorded.Clinical outcome of latest follow-up was evaluated by X-ray and CT scan.Results The time of operation was 2.0-2.5 h and blood loss was 150-300 ml.All the patients were followed-up for 9 to 18 months (mean,11.5±2.1 months).The VAS of neck pain improved from 3.6±2.7 (range,2.0-5.0) pre-operatively to 1.4±0.2 (range,0-2.0) 12 months postoperatively (P=0.000).The JOA score improved from 11.7± 1.9 (range,10.0-15.0) pre-operatively to 15.3±0.6 (range,14.0-17.0)12 months post-operatively (P=0.000).The improvement rate of JOA score at the latest follow-up was 54.1％± 12.4％,including 23 cases (85.19％) excellent,and 4 cases (14.81％) good.The results of axial symptoms were no-symptom in 22 cases (81.48％) and mild symptoms in 5 cases (18.52％).Postoperative cervical spine X-ray and CT showed that the sagittal cervical spine alignment was restored.There was statistically significant difference between ADI of 4.3±1.1 mm (range,3.9-4.5 mm) pre-operatively to 2.5± 0.4 mm (range,2.1-2.6 mm) 12 months post-operatively,which was improved significantly (P=0.000).There were no complications found during the follow-up.Conclusion The application of axial spinous process-muscle-vascellum complex transplantation for posterior atlantoaxial fixation can preserve the dynamic function of muscles and reduce the postoperative pain,as well as avoid donor site morbidity.

Objective: To summarize our preliminary clinical experience of ultrasound-guided needle-perc combined with standard percutaneous nephrolithotomy (PCNL) in the treatment of staghorn stones, and to analyze its safety and efficacy. Methods: The clinical data of 65 patients with staghorn stones treated by ultrasound-guided needle-perc combined with standard PCNL under general anesthesia with the patient in prone position from December 2017 to June 2019 were retrospectively reviewed. A total of 41 males and 24 females were included. The mean age was (53.5+ 8.9) years. The mean body mass index (BMI) was (25.1±2.9) kg/m², and the mean stone diameter was (10.9±3.1) cm. Among them, there were 3 cases with bilateral staghorn stones, 38 cases with complete staghorn calculi, 36 cases with non- or mild preoperative hydronephrosis, 12 cases with previous ipsilateral renal surgery, and 9 cases with solitary kidneys. Ultrasound-guided renal access and tract dilation were used to establish F24 standard channel. Pneumatic combined with ultrasonic lithotripsy with suction system was used to treat staghorn stones under nephroscope. Needle-perc consists of F4.2 needle-like metal sheath connected with a three-way tube. A 0.6 mm diameter video fiber, 200 um holmium laser fiber and liquid perfusion device can be connected through the three-way tube respectively. The residual stone in the parallel calyx after standard PCNL were punctured by needle-perc under ultrasound guidance, and then the holmium laser fiber was used for lithotripsy. Results: In this study, a total of 68 renal units were included. The median operative time was 79.8 minutes, ranging 45-129 minutes. The median decrease of hemoglobin on postoperative day 1 was 10.6 g/L, ranging 0-25.9 g/L. The median length of postoperative hospital stay was 5.5 days, ranging 4-7 days and the median time of tract establishment was 4.8 minutes, ranging 2.5-9.6 minutes. The median number of standard tract established was 1.5, ranging 1-3 and the median number of needle-perc punctured was 1.0, ranging 1-3. The total complication rate was 10.3% (7 cases), including 5 cases of Clavien grade Ⅰ, 2 cases of postoperative fever, 3 cases of analgesic use. There were 2 cases of Clavien grade Ⅱ. All of them were blood transfusion. The initial stone free rate was 79.4%(54/68). Of the 14 patients with residual stones, 9 patients underwent second-stage operation, 7 patients were stone free, and the final stone free rate was 89.7%(61/68). Conclusions Ultrasound-guided needle-perc combined with standard PCNL is safe and effective in the treatment of staghorn stone.

Objective:To investigate the anatomical safety and feasibility ofposterior occipitocervical fixation with atlan-tooccipital-clivus screw.Methods:Data of 60 patients who treated in the spinal department of our hospital with upper cervical computed tomographic scans from February 2017 to November 2019 were retrospectively collected. Occipitocervical infection, injury, tumor and deformity were excluded. The Mimics software was used to reconstruct the occiput, atlas and measure the anatomical parameters, including the height and width of the anterior edge of the clivus, the height and width of the middle part of the clivus, the thinnest distance of the soft tissue in front of the clivus, the anteroposterior diameter, transverse diameter, the angle of inside tilting in coronary plane of the occipital condyle, the distance from the hypoglossal canal to the atlantooccipital articular surface, the anteroposterior diameter and transverse diameter of the superior joint of atlas, the height of the lateral mass, and the height and transverse diameter of the inferior articular process of the superior atlas joint. The three-dimensional digital modeling was performed and the screw diameter of 3.5mm was simulated. 3-Matic software were used to measure the screw placement parameters, including the inside tilting angle in coronary plane of screw, and the angle of upper tilting in sagittal plane and length of screw. The atlanto-occipital junction was exposed at the rear of 8 cadavers. According to the above parameters, the titanium alloy screws with a diameter of 3.5 mm were transferred from the inferior articular process and posterior arch of the atlas to the clivus through the atlantooccipital. Finally, the screw path was cut along the nail path with a pendulum saw, and the track of the screw was observed to confirm the safety and effectiveness of the screw.Results:The leading edge height and width of male clivus was 16.8±2.5 mm and 20.1±3.1 mm. The middle part of the clivus was 9.7±2.3 mm and 22.4±3.7 mm. The thinnest soft tissue in front of the clivus was 5.8±1.48 mm. The anteroposterior diameter of the occipital condyle was 19.1±1.9 mm, the transverse diameter was 12.6±2.0 mm, the inside tilting angle was 33.7°±4.5°, and the vertical distance from the lowest point of the neural tube to the articular surface of the occipital condyle was 9.6±1.1 mm. The height of the lateral mass of atlas was 12.9±2.4 mm, the anteroposterior diameter of the upper joint of atlas was 21.7±1.9 mm, and the transverse diameter was 11.7±1.4 mm. The width of the inferior facet was 14.9±1.4 mm and the height of the inferior facet was 5.7±0.85 mm. The distance from the screw entry point to the vertical line of the lateral mass migration midpoint was 2.5±0.6 mm; The distance from the screw entry point to the horizontal line of the midpoint was 2.3±0.7 mm.The inside titling angle of screw was 18.4°±1.6°, the upper tilting angle was 55.6°±3.1°, the length of the screw track was 53.0±2.8 mm, the adjustment range of upper tilting angle was 15.0±2.8 mm, the adjustment range of inside tilting angle was 10.4±2.4 mm. The anatomical parameters of females were slightly smaller than those of males, and the difference was statistically significant, but there was no significant difference between left and right parameters. The screws of 8 specimens could be inserted safely and effectively.Conclusion:Atlan-tooccipital-clivus screw can be implanted without damaging the nerve and vascular structure, and it can be used as a choice for occipitocervical fixation.

Objective To describe and introduce the initial clinical application of a novel instrument needle-perc for percutaneous nephrolithotomy (PCNL) in upper urinary tract stones.Methods 24 patients with upper urinary stone treated by PCNL were collected retrospectively between August 2017 and January 2018.Sixteen patients were male and 8 were female.Average age was 41.2 years,ranging 26-65 years.Eight cases had upper pole stones,6 cases had pelvic stones,8 cases had lower pole stones and 4 cases had the stone in UPJ.The mean calculus size was 1.2 cm,ranging 0.5-1.4 cm.All patients were punctured under total ultrasound with needle-perc.Six cases had upper calyceal puncture,10 cases had middle calyceal puncture and 8 cases had lower calyceal puncture.The needle-shaped nephroscope consists of a puncture sheath and a needle handle.The puncture sheath is a hollow metal sheath with an outer diameter of F4.2,an inner diameter of F3.6,and a length of 15 cm.The tip of the sheath is beveled to facilitate puncture.The outer end of sheath is connected to the needle handle through a screw interface.And the three interfaces of the three-way tube can be respectively connected with a liquid irrigation device,a video optical fiber and a 200 μm holmium laser fiber.The needle-perc integrated image system,the irrigation system,and the nephroscope channel are integrated.The tissue passing through the needle can be simultaneously observed through video optical fiber during puncturing.After the tip of the sheath is inserted into the target calyx,the holmium laser fiber is connected for fragmenting or dusting.Results Needle-perc was successful in 22 cases,2 patients were converted to larger tract(F16).The mean opeartive time was 49.2 min,ranging 22-75 min and the mean hemoglobin loss was 5.2 g/L,ranging 0-13.8 g/L.Mean postoperative hospital stay was 3 days,ranging 1 to 6 days.No Double-J stents or nephrostomy tube was placed in the 22 patients.Complications (Clavien Ⅱ) occurred in 4 cases,including fever in 2 cases and renal colic in 2 cases.Plain film of KUB or CT scan was done and stone free rate at 1 month was 90.9％ (20/22),2 patients needed ESWL to remove the residual stones.Conclusions Needle-perc is efficient and safe for small renal stones (size ＜ 1.5 cm) from our initial experience,with high stone-free rate and low complication rate in early follow-up.

Objective:To investigate the clinical significance of a new classification system for atlas fractures based on pre- and post-treatment CT features, with a focus on diagnosis and treatment.Methods:A retrospective analysis was conducted on 75 cases of cervical vertebra fractures treated at the Sixth Hospital of Ningbo City between January 2015 and December 2020. The study included 44 males and 31 females, with an average age of 53.3±13.0 years (range: 27-81 years). The fractures were classified according to the Landells classification, resulting in 12 cases of type I, 13 cases of type II, 33 cases of type III, 9 cases that were difficult to classify due to fracture lines located at anatomical junctions, and 8 cases that could not be classified using the Landells classification due to diverse injury mechanisms. To establish a new preliminary classification for cervical vertebra fractures, the researchers considered whether the fracture line in the CT images involved the facet joint surface of the atlas, the impact on bilateral half-rings, and the displacement distance of the fracture ends. Five spinal surgeons were randomly selected to classify the CT images of the 75 patients using the new classification method. After one month, the imaging data of the 75 cases of cervical vertebra fractures were randomized and reclassified to assess the reliability and repeatability of the classification.Results:The new cervical vertebra fracture classification method comprised three types based on whether the fracture line involved the facet joint surface of the atlas: type A (no involvement of the facet joint surface of the atlas), type B (involvement of one side of the facet joint surface with intact contralateral half-ring), and type C (involvement of one side of the facet joint surface with fractured contralateral half-ring). Additionally, based on the maximum displacement distance between the fracture ends (>4 mm), six subtypes were identified: subtype 1 (≤4 mm displacement) and subtype 2 (>4 mm displacement). Consequently, the subtypes were classified as A1, A2, B1, B2, C1, and C2. According to the new classification method, the 75 patients included 17 cases of A1, 12 cases of A2, 7 cases of B1, 13 cases of B2, 12 cases of C1, and 14 cases of C2. The classification demonstrated excellent consistency, as assessed by the five doctors, with Kappa values of 0.85 and 0.91 for reliability and repeatability, respectively. At the final follow-up, all conservatively treated patients achieved bone healing, while four surgically treated patients experienced non-union of the fracture ends but exhibited good fusion between the atlas and axis. The remaining surgically treated patients achieved bony union without complications such as loosening or fracture of internal fixation.Conclusion:The new cervical vertebra fracture classification method, based on CT imaging features, comprehensively covers common clinical cases of cervical vertebra fractures and demonstrates excellent consistency. It provides valuable clinical guidance for the diagnosis and treatment of cervical vertebra fractures.

Objective:To summarize the preliminary clinical experience of utilizing ureteral balloon dilation catheter in the treatment of "difficult ureter" during ureteroscopic lithotripsy, and to discuss the efficacy and safety of the technique.Methods:Clinical data of 28 patients (30 sides) with upper urinary tract calculi admitted to Beijing Tsinghua Changgung Hospital Affiliated to Tsinghua University from April 2021 to July 2022 were retrospectively analyzed. There were 23 males (82.1%) and 5 females (17.9%), with age of (51.5±13.6) years. Among the 30 sides, 20 (66.7%) on the left and 10(33.3%) were on the right. Calculi were either located in the renal pelvis or calyxes in 7 sides (23.3%), upper ureter in 17 sides (56.7%), and lower ureter in 6 sides (20.0%). The maximum diameter of the stones was (9.4±4.2)mm, and 23 sides (76.7%) were combined with hydronephrosis before surgery. When "difficult ureter" was encountered during the procedure, that is, it was difficult to insert ureteroscope or ureteral access sheath (UAS) due to small ureteral lumen, balloon catheter was used for dilation in the first stage, in which the balloon diameter was 4 mm on 22 sides and 5mm on 8 sides. The instrument was retrogradely inserted through the working channel of F8 semi-rigid ureteroscope, and the small site of the ureteral lumen was dilated under direct endoscopic view. After a single dilation, the balloon catheter was withdrawn, and the effect of dilation was evaluated by semi-rigid ureteroscopy to determine whether to proceed with the following procedures. The intraoperative data were recorded, including surgical method, stage of "difficult ureter" occurred, site of the small part of the ureter, related data of utilizing ureteral dilatation balloon catheter, grade of ureteral injury after dilatation (according to the 0-4 grading classification of endoscopic ureteral injuries), total operation time, balloon catheter-related adverse events, stone-free rate, and time of removing ureteral stents.Results:Among the 30 sides, 29 (96.7%) had difficulty in the stage of ureteroscope insertion, and 1(3.3%) had difficulty in the stage of UAS insertion. A total of 37 small sites of ureter were involved, including 18 in the intramural segment, 10 in the lower part, 2 in the middle part, and 7 in the upper part. Each site was dilated once with a median time of 3 (0.5, 5.0) minutes and a median maximum balloon pressure of 1 215.9(1 215.9, 1 443.9)kPa[12.0(12.0, 14.3)atm]. There were 28 sites of grade Ⅰ injury, 8 sites of grade Ⅱinjury, and 1 site of grade Ⅲinjury. The total duration of unilateral procedure was (73.4±30.3) min. Ureteroscope or UAS insertion was successful in 28 sides(93.3%) after balloon dilation, and failed in 2 sides(6.7%), both of which were in the stage of inserting ureteroscope and ureteral stent was indwelled for the second-stage procedures. On the first day after surgery, the hemoglobin level was (134.1±12.9)g/L, which was significantly different from the preoperative parameters ( P<0.01), and serum creatinine level was (86.7±23.2)μmol/L, which showed no significant difference from the preoperative one ( P=0.263). The primary stone-free rate was 92.9% (26/28), and the total postoperative complication rate was 13.3% (4/30), including 3 of grade Ⅰ (lateral lower abdominal pain requiring additional analgesic drugs) and 1 of grade Ⅱ (postoperative hematuria requiring intravenous hemostatic drugs). Follow-up was conducted for 3 months. All of the 28 successful sides had their ureteral stents removed before the last follow-up, and the time of removal was (36.9±11.5) days. No hydronephrosis was found in the ipsilateral kidney by ultrasound 3 months after operation. Conclusions:Balloon dilation technique showed good efficacy and safety in the treatment of "difficult ureter" during ureteroscopic lithotripsy.