Objective:To develop a robotic digestive endoscope system (RDES) and to evaluate its feasibility, safety and control performance by experiments.Methods:The RDES was designed based on the master-slave control system, which consisted of 3 parts: the integrated endoscope, including a knob and button robotic control system integrated with a gastroscope; the robotic mechanical arm system, including the base and arm, as well as the endoscopic advance-retreat control device (force-feedback function was designed) and the endoscopic axial rotation control device; the control console, including a master manipulator and an image monitor. The operator sit far away from the endoscope and controlled the master manipulator to bend the end of the endoscope and to control advance, retract and rotation of the endoscope. The air supply, water supply, suction, figure fixing and motion scaling switching was realized by pressing buttons on the master manipulator. In the endoscopy experiments performed on live pigs, 5 physicians each were in the beginner and advanced groups. Each operator operated RDES and traditional endoscope (2 weeks interval) to perform porcine gastroscopy 6 times, comparing the examination time. In the experiment of endoscopic circle drawing on the inner wall of the simulated stomach model, each operator in the two groups operated RDES 1∶1 motion scaling, 5∶1 motion scaling and ordinary endoscope to complete endoscopic circle drawing 6 times, comparing the completion time, accuracy (i.e. trajectory deviation) and workload.Results:RDES was operated normally with good force feedback function. All porcine in vivo gastroscopies were successful, without mucosal injury, bleeding or perforation. In beginner and advanced groups, the examination time of both RDES and ordinary endoscopy tended to decrease as the number of operations increased, but the decrease in time was greater for operating RDES than for operating ordinary endoscope (beginner group P=0.033; advanced group P=0.023). In the beginner group, the operators operating RDES with 1∶1 motion scaling or 5∶1 motion scaling to complete endoscopic circle drawing had shorter completion time [1.68 (1.40, 2.17) min, 1.73 (1.47, 2.37) min VS 4.13 (2.27, 5.16) min, H=32.506, P<0.001], better trajectory deviation (0.50±0.11 mm, 0.46±0.11 mm VS 0.82±0.26 mm, F=38.999, P<0.001], and less workload [42.00 (30.00, 50.33) points, 43.33 (35.33, 54.00) points VS 52.67 (48.67, 63.33) points, H=20.056, P<0.001] than operating ordinary endoscope. In the advanced group, the operators operating RDES with 1∶1 or 5∶1 motion scaling to complete endoscopic circle drawing had longer completion time than operating ordinary endoscope [1.72 (1.37, 2.53) min, 1.57 (1.25, 2.58) min VS 1.15 (0.86, 1.58) min, H=13.233, P=0.001], but trajectory deviation [0.47 (0.13, 0.57) mm, 0.44 (0.39, 0.58) mm VS 0.52 (0.42, 0.59) mm, H=3.202, P=0.202] and workload (44.62±21.77 points, 41.24±12.57 points VS 44.71±17.92 points, F=0.369, P=0.693) were not different from those of the ordinary endoscope. Conclusion:The RDES enables remote control, greatly reducing the endoscopists' workload. Additionally, it gives full play to the cooperative motion function of the large and small endoscopic knobs, making the control more flexible. Finally, it increases motion scaling switching function to make the control of endoscope more flexible and more accurate. It is also easy for beginners to learn and master, and can shorten the training period. So it can provide the possibility of remote endoscopic control and fully automated robotic endoscope.

Objective:To investigate the risk factors of bronchopulmonary dysplasia (BPD) in very low birth weight (VLBW) infants with gestational age ≤32 weeks within 28 days after birth and to establish and validate the nomogram model for BPD prediction.Methods:We retrospectively chose VLBW infants with gestational age ≤32 weeks who survived to postmenstrual age (PMA) 36 weeks and were admitted to the neonatal intensive care unit of Peking University Third Hospital from January 2016 to April 2020 as the training cohort. BPD was diagnosed in accordance with the 2018 criteria. The clinical data of these infants were collected, and the risk factors of BPD were analyzed by Chi-square test, Mann-Whitney U test, and multivariate logistic regression, and a nomogram model was established. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was used to assess the predictive performance. Decision curve analysis (DCA) was constructed for differentiation evaluation, and the calibration chart and Hosmer-Lemeshow goodness of fit test were used for the calibration evaluation. Bootstrap was used for internal validation. VLBW infants with gestational age ≤32 weeks survived to PMA 36 weeks and admitted to Hebei Chengde Maternal and Child Health Hospital from October 2017 to February 2022 were included as the validation cohort. ROC curve and calibration plot were conducted in the validation cohort for external validation. Results:Of the 467 premature infants included in the training cohort, 104 were in the BPD group; of the 101 patients in the external validation cohort, 16 were in the BPD group. Multivariate logistic regression analysis showed that low birth weight ( OR=0.03, 95% CI: 0.01-0.13), nosocomial pneumonia ( OR=2.40, 95% CI: 1.41-4.09), late-onset sepsis ( OR=2.18, 95% CI: 1.18-4.02), and prolonged duration of endotracheal intubation ( OR=1.61, 95% CI: 1.26-2.04) were risk factors for BPD in these groups of infants (all P<0.05). According to the multivariate logistic regression analysis results, a nomogram model for predicting BPD risk was established. The AUC of the training cohort was 0.827 (95% CI: 0.783-0.872), and the ideal cut-off value for predicted probability was 0.206, with a sensitivity of 0.788 (95% CI: 0.697-0.862) and specificity of 0.744 (95% CI: 0.696-0.788). The AUC of the validation cohort was 0.951 (95% CI:0.904-0.999). Taking the prediction probability of 0.206 as the high-risk threshold, the sensitivity and specificity corresponding to this value were 0.812 (95% CI: 0.537-0.950) and 0.882 (95% CI: 0.790-0.939). The Hosmer-Lemeshow goodness-of-fit test in the training and validation cohort showed a good fit ( P>0.05). DCA results showed a high net benefit of clinical intervention in very preterm infants when the threshold probability was 5%~80% for the training cohort. Conclusion:Low birth weight, nosocomial pneumonia, late-onset sepsis, and prolonged tracheal intubation duration are risk factors for BPD. The established nomogram model has a certain value in predicting the risk of BPD in VLBW less than 32 weeks.

Objective:To summarize the clinical features, treatment and prognosis of asparaginase (ASP) related cerebral venous sinus thrombosis (CVST).Methods:Clinical profiles including age, sex, first symptoms, coagulation function, imaging findings, ASP type, treatment and prognosis of eight acute lymphoblastic leukemia (ALL) or lymphoblastic lymphoma (LBL) children with ASP related CVST at the Department of Pediatrics, First Affiliated Hospital of Zhengzhou University from November 2016 to October 2021 were analyzed retrospectively.Results:Eight CVST children were all male, including 6 ALL and 2 LBL, with the onset age ranged from 5 to 15 years, 6 cases occurred in the stage of first induction remission, and the initial symptom were mainly epileptic seizures (7 cases). Magnetic resonance imaging combined magnetic resonance venography (MRV) showed the most common site of venous sinus enlargement was superior sagittal sinus (8 cases). Secondary cerebral hemorrhage was found in 5 cases. D-dimer elevated on the day of onset in all cases. Three patients were treated with intravascular mechanical thrombectomy and thrombolysis combined with anticoagulant therapy, 3 patients were treated with continuous anticoagulant therapy only, 2 patients were not treated with anticoagulant therapy. MRV follow-up for 3 months showed that the thrombi in patients were almost completely absorbed except in 2 patients who were not treated with anticoagulant therapy. Thrombolysis combined with anticoagulant therapy was the fastest way for thrombosis absorption. Among 8 patients, 1 died of early recurrence of ALL, and 7 patients accepted further asparaginase and no CVST recurrence or progression was found. There were no sequelae of nervous system except 1 patient with left upper limb muscle strength impairment.Conclusions:ASP related CVST is more common in older male children and the prognosis is good. ASP related CVST occurred mostly in the stage of first induction remission, and most initial manifestation is epileptic seizure. The superior sagittal region is a common site of thrombus, magnetic resonance imaging combined with MRV is helpful for accurately diagnosis. Timely anticoagulant treatment can improve the prognosis, and mechanical thrombectomy and thrombolysis can quickly recanalize the vessel.

Objective To evaluate the early clinical outcomes and complications of oblique lateral interbody fusion (OLIF) in the treatment of degenerative lumbar diseases.Methods All of 83 patients,29 males and 54 females with ages from 32 to 83 (average 60.8± 13.7 y),underwent OLIF with or without posterior pedicle screw-rod instrumentations from October 2014 to February 2017.The index diagnosis was discogenic back pain in 17 cases,spondylolisthesis in 23,lumbar spinal canal stenosis in 25,and degenerative lumbar spinal kyphoscoliosis in 18 cases.The distribution of operative level was 5 at L1,2,13 at L2,3,38 at L3,4,and 69 at L4,5.The mean number of fusion level for each case was 1.5 segments.The operative duration,blood loss during operation,intra-operative and post-operative complications,the length of post-operative hospital stay were recorded.Clinical outcomes were evaluated using visual analogue scale (VAS) and Oswestry disability index (ODI).All patients were followed up for at least 3 months.Lumbar X-ray and CT scans were taken and the clinical outcomes were re-assessed during follow-up.Results Fifty-one in the 83 patients underwent supplementary posterior pedicle screw-rod instrumentation with OLIF procedures.The operation lasted for 43-295 min,with a mean duration of (153 ± 72) min.Mean operation time for each OLIF segment was 43± 12 min.Blood loss during the operation was 30-800 ml,with a mean of 125±74 ml.Mean blood loss for each OLIF segment was 27±13 min.Average length of stay was 5.6 ± 3.2 d,ranging from 3-15 d.The VAS for back pain and leg pain and ODI scores were decreased apparently for each patient.The total incidence of complications was 22.9％ (19/83),including 6.0％ (5/83) of intra-operative complications (4 cases of cage subsidence,1 case of segmental artery injury) and 16.9％ (14/83) of post-operative ones.The latter consisted of ipsilateral hip flexor weakness in 6,ipsilateral anterolateral thigh pain in 2,ipsilateral lateral thigh numbness in 1,contralateral pain in flexion of hip in 1,ipsilateral sympathetic chain injury in 2,and pain in area of iliac bone donor site in 2.All symptoms were released or disappeared during follow-up.Conclusion OLIF as a novel minimally invasive technique can act as a safe and effective treatment for degenerative lumbar diseases,which can also reduce approach-related complications.

Objective To investigate the indirect decompression effect of oblique lateral interbody fusion (OLIF) in the treatment of mild to moderate degenerative lumbar stenosis.Methods From October 2014 to November 2016,23 patients with mild to moderate lumbar spinal stenosis underwent OLIF combined with or without posterior pedicle screw fixation;9 males and 14 females with average age of 59.2±11.6 years old;8 cases at L3,4 segment and 15 cases at L4,5 segment.All cases were followed up for more than 6 months.Thin layer scanning of CT and two-dimensional reconstruction images were used to measure the vertical diameter and area of intervertebral foramen.Intervertebral disc height and spinal canal anteroposterior diameter were measured on median sagittal MRI sequence,and the anteroposterior diameter and the cross-sectional area of the spinal canal were measured on cross-sectional MRI sequence.The clinical effects were assessed by the visual analogue score (VAS) and the Oswestry disability index (ODI) for low back pain,lower limb pain and lower limb numbness.Results Compared with those measurements pre-operatively,the post-operative intervertebral disc height increased by 78.6％±13.4％.The post-operative left vertical diameter of intervertebral foramen increased by 36.7％±7.8％,and the post-operative left area of intervertebral foramen increased by 36.6％± 8.7％,and the post-operative right vertical diameter of intervertebral foramen increased by 40.7％±9.6％,and the post-operative right area of intervertebral foramen increased by 40.0％±8.9％.The post-operative anteroposterior diameter of sagittal spinal canal were increased 32.6％ ± 5.9％,and the post-operative anteroposterior diameter of cross-sectional spinal canal were increased 34.4％±6.8％,and the post-operative cross-sectional area of the spinal canal were increased 47.5％±7.2％.All of the differences were statistically significant between pre-operative and post-operative measurements.The VAS score for low back pain was 6.2± 1.7 pre-operatively,and 1.1±0.5 post-operatively.The ODI for low back pain was 81.2％± 18.2％ pre-operatively,and 6.1％±2.0％ post-operatively.The VAS score for lower limb pain was 5.6±1.4 pre-operatively,and 0.8±0.3 post-operatively.And the VAS score for lower limb numbness was 6.6±2.0 pre-operatively,and 3.4± 1.2 post-operatively.All of the differences were statistically significant between pre-operative and post-operative evaluations.Conclusion There were obvious radiological evidences and remarkable clinical effect of indirect decompression using OLIF technique in treatment of mild to moderate lumbar spinal stenosis at early post-operative stage.However further long-term follow-up studies with multicenter large sample were still needed.

Objective To evaluate the clinical outcomes of oblique lateral interbody fusion (OLIF) in the treatment of adult degenerative scoliosis (ADS).Methods From January 2015 to May 2016,17 ADS patients,4 males and 13 females were enrolled with ages from 46 to 80 (average 69.5±9.2 years).The Cobb angle of all was greater than 10°.According to Lenke-Silva classification systems:Ⅰ level,2 cases,decompression alone;Ⅱ level,2 cases,decompression and limited instrumented spinal fusion;Ⅲ levels,4 cases,decompression and lumbar curve instrumented fusion;Ⅳ levels,5 cases,decompression with anterior and posterior spinal instrumented fusion;Ⅴ level,4 cases,thoracic instrumentation and fusion extension.The operation time,blood loss,blood transfusion,and preoperative and postoperative complications were recorded.Clinical and radiological outcomes were evaluated using visual analogue scale (VAS),Oswestry disability questionnaire (ODI) scores,sagittal vertical axis (SVA) and coronal Cobb.All cases were followed up in 3,6,12 and 24 months.Results All of 17 cases underwent OLIF,one level 4 cases,two levels 2 cases,three levels 7 cases and four levels 4 cases.Alone OLIF was 5 cases (2 case of Ⅰ level,1 case of Ⅱ level,1 case of Ⅲ level and 1 case of Ⅳ level).OLIF combined with posterior approach was 12 cases and the interval time were 1-2 weeks,the mean were 1.7±0.5 weeks.Among these 12 cases,posterior fixation was 6 cases,posterior fixation and decompression was 2 cases,and L5/S1 interbody fusion was 4 cases.The operation lasted for 50-460 min,with a mean duration of 230.6± 132.0 min.Blood loss during the operation was 30-640 ml,with a mean of 306.5±213.8 ml.No patient had blood transfusion.The follow-up was 12-28 months and the mean was 17.9±4.5 months.The preoperative Cobb angles were 16.2°-37.7°,the mean was 29.1°±6.4°.The postoperative Cobb angle were 1.5°-10.2°,and the mean were 5.6°±2.4°.The Cobb of all cases improved significantly.The SVA was returned to the normal level in 4 cases of Lenke-Silva V level.The VAS and ODI score decreased from 7.1 ±0.7 preoperatively to 2.4±0.9 at last follow-up,and from 37.9±2.5 to 10.9±3.0,respectively,and both of them were improved significantly.2 cases of OLIF had cage malposition.Left hip flexor weakness occurred in 5 cases and recovered completely within 2 weeks.Left anterior thigh pain occurred in 1 case and disappeared within 2 weeks.Left sympathetic chain injury happened in 1 case and recovered at last follow-up.Conclusion OLIF as a management of ADS showed excellent short-term outcomes.Clinical and radiological results,such as VAS,ODI and Cobb angle,were improved in all cases.OLIF will be a good choice for the treatment of ADS.

Objective To assess the effects of the risk factors of grafts from donors after cardiac death (DCD) on the prognosis of liver transplantation (LT).Methods In this retrospectively study,215 cases of LT using DCD donor grafts were performed at our institution from September 2013 to January 2017.Due to the loss to follow-up in 4 cases,211 cases were enrolled in the study.The following DCD donor data were collected:gender,age,primary disease,ABO blood type,body mass index (BMI),medical history (fatty liver,hypertension),ICU hospitalization time,mechanical ventilation time,warm ischemia time,cold ischemia time,and indexes of routine laboratory test before donation.Statistical analyses using the Kaplan-Meier method,log-rank test,multivariate step-wise Cox regression were performed.Results Of the 211 donors,univariate analysis showed that the overall 6-month,1-,and 3-year survival rate after DCD LT was 88％,84％,and 82％,respectively.Univariate analysis showed that donor serum sodium level ＜136 mmol/L (P =0.018) and cold ischemia time ＞9 h (P =0.013) were all significant risk factors affecting overall survival after DCD LT.Additionally,donor BMI ＞30 kg/m2 (P =0.011) and donor age ＞60 years (P =0.025) were significantly associated with postoperative complications.Multivariate analysis showed that donor serum sodium level (P=0.025) was an independent risk factor of survival after DCD LT.Conclusion To select suitable DCD liver allografts and control risk factors of donor can help to improve outcomes of recipients.

Objective To evaluate and discuss the clinical outcomes and advantages of midline lumbar fusion (MIDLF) with cortical bone trajectory (CBT) screw in the reoperation of lumbar disease. Methods From June 2014 to August 2015, a total of 12 patients, 5 male and 7 female with an average age of 68.5±5.6 years old (ranged from 56-76 years). The indications of reoper-ation including:5 cases of adjacent segment disease, 2 cases of discogenic back pain after lumbar dynamic stabilization, 5 cases of recurrent disc herniation. The interval time from primary surgery to second surgery was 3-9.5 years (average 6.0±2.0 years). Dis-ease level:L2/31 case, L3/42 cases, L4/57 cases, L5/S12 cases. All cases were got the X-ray, CT scan and MRI examination before surgery. The operative duration, blood loss, complications were all evaluated. Back and leg pain were recorded by visual analogue scale (VAS) scores. Functional recovery was evaluated by Oswestry disability index (ODI). Results Operative time was 110-210 min, and mean duration was (158.3±36.4) min. Blood loss was 150-310 ml, and mean loss was (231.7±51.0) ml. There was 1 case of cerebrospinal fluid leakage which treated with pillow supine for 1 week after surgery, and strengthened the prevention of antibi-otics, incision healing, with no headache and other low intracranial pressure of dizziness, the remaining patients had no intraopera-tive and postoperative complications. The time of follow-up was 12-25 months, with an average of (17.9 ± 4.6) months. The back pain of VAS score of preoperative was 3.9±1.4, and the last follow-up was 1.9±0.5, the difference was statistically significant (t=4.506, P=0.001). The VAS score of preoperative leg pain (4.9±1.4) was significant higher than the last follow-up (1.2±0.6, t=9.134, P=0.000). The preoperative ODI was 32.9±3.4, and last follow-up was 13.3±3.2, and the difference was statistically significant (t=15.002, P=0.000). Conclusion MIDLF was applicable with good clinical outcome and technical advantages in current cases, and it might be a choice of reoperation for lumbar disease.

Objective To compare the clinical and radiographic outcomes of 3 kinds of lumbar interbody fusion (ALIF,PLIF,TLIF) for adult low-grade isthmic spondylolisthesis at L4.5 and L5S1 levels.Methods Data of seventy patients with lowgrade isthmic spondylolisthesis who had undergone different lumbar interbody fusion (LIF) procedures according to the assessment of the clinical manifestation,neurological symptoms,plane of the common iliac vessels and the width of vascular window by three-dimensional computed tomography angiography between May 2004 and May 2014 were retrospectively reviewed.21 patients had undergone anterior LIF (ALIF)(13 males and 8 females with an average of 43.29±8.15 years old (range,29-53 years old);L4,5 in ten,L5S1 in 11;Meyerding grade Ⅰ 10 cases,grade Ⅱ 11 cases);25 patients had undergone posterior LIF (PLIF) (12 males and 13 females,with an average of 44.04±12.71 years old (range,25-64 years old);L4.5 in 12,L5S1 in 13;Meyerding grade Ⅰ 15 cases,grade Ⅱ 10 cases) and 24 patients had undergone transforaminal LIF (TLIF) (12 males and 12 females with an average of 45.00± 9.36 years old (range,34-62 years old);L4,5 in 12,L5S1 in 12;Meyerding grade Ⅰ 11 cases,grade Ⅱ 13 cases).Results All patients were followed up for 24-37 months (average,25.6±8.7 months).The visual analogue scale (VAS) in all groups were decreased from 7.05±0.87 (ALIF),6.60±1.39 (PLIF),6.75±1.11 (TLIF) pre-operation to 0.90±0.70,0.96±0.68,1.04±0.62 24 months after operation.Oswestry disability index (ODI) scores were decreased from 78.53％±6.25％,79.80％±6.55％,79.92％±8.10％ preoperation to 17.14％±3.01％,21.32％±4.40％,22.46％±3.87％.Perioperative data including operation time,blood loss,postoperative blood drainage,length of stay showed no significant difference between ALIF group and TLIF group,but showing significant difference comparing with PLIF group.The imageological results showed that ALIF procedure increased whole lumbar lordosis (WL) and disc height (DH),showing no significant difference comparing with PLIF group,but showing significant difference comparing with TLIF group.The ALIF procedure increased segmental lordosis angle (SL),showing significant difference comparing with PLIF group and TLIF group.The PLIF procedure decreased spondylolisthesis index (SI),showing significant difference comparing with A/TLIF group,but showing no significant difference between ALIF group and TLIF group.There was no significant difference showed comparing the L1 axis S1 distance (LASD) and sacral slope (SS),in three groups.The graft fusion was achieved in all patients after 6-8 months postoperatively without instrument failure or displacement.Conclusion Three surgical procedures of lumbar interbody fusion for adult low-grade isthmic spondylolisthesis showed silimar clinical efficacy.The ALIF procedure is superior in its capacity to restore WL,DH,and SL,and the P/TLIF procedure are superior in correcting the vertebral slippage and spinal cord decompression.

Objective To investigate a reliable and practicable model of intraoperative neurophysiological monitoring (IONM) in oblique lateral interbody fusion (OLIF) combined with posterior transpedicle internal fixation.Methods A total of 34 consecutive patients who underwent OLIF combined with posterior transpedicle internal fixation with IONM at the SRRSH from November 2014 to July 2016 were collected and follow-up at least for 3 months postoperative.The intraoperative somatosensory evoked potentials (SEP),motor evoked potentials (MEP),dermatomal somatosensory evoked potential (DSEP) and spontaneous electromyography (sEMG) were used and evaluated,besides,triggered electromyography (tEMG) was used to monitor the implantation of pedicle screws,the possible reasons and treating procedures of monitoring alerts were summarized.Results A total of 34 cases of patients were effectively monitored during OLIF combined with posterior transpedicle internal fixation.SEP monitoring was successful in all patients,and no abnormal SEPs were observed in all cases.DSEP monitoring was successful in 20 cases (58.8％),and no abnormal DSEPs were observed in these patients.MEP was successfully monitored in all cases,eliminating the anesthesia factor,no abnormal MEPs were observed in all cases.The sensitivity and positive predictive value of SEP,MEP,DSEP were 0％.3 cases had abnormal sEMG reactions during the channel establishment which disappeared after adjustment of channel,and 2 cases which appeared abnormal wave recovered after brief observation.Among the 5 patients with abnormal wave,one case got numbness,one patient felt pain in front of the thigh postoperative.Among the other 29 patients without abnormal wave during channel establishment,one case appeared numbness.These 3 patients with neurologic symptoms recovered in 3 months after conservative treatment.The sensitivity and specificity of sEMG was 66.7％ and 90.3％ respectively,negative predictive value and positive predictive value were 96.6％ and 40％ respectively.6 screws got tEMG response after tapping even the intensity was less than 10mA,which showed broken codex of pedicle according to postoperative CT scan.Cornclusion Intraoperative application of sEMG monitoring in OLIF can obviously reduce the incidence of the neurological deficit,which was an effective method,tEMG monitoring during lumbar pedicle screw fixation can detect the mal-positioned screws and protect the nerve roots.SEP,MEP and DSEP did not seem well suited for OLIF.