The gradient field, one of the core magnetic fields in magnetic resonance imaging (MRI) systems, is generated by gradient coils and plays a critical role in spatial encoding and the generation of echo signals. The uniformity or linearity of the gradient field directly impacts the quality and distortion level of MRI images. However, traditional point measurement methods lack accuracy in assessing the linearity of gradient fields, making it difficult to provide effective parameters for image distortion correction. This paper introduced a spherical measurement-based method that involved measuring the magnetic field distribution on a sphere, followed by detailed magnetic field calculations and linearity analysis. This study, applied to assess the nonlinearity of asymmetric head gradient coils, demonstrated more comprehensive and precise results compared to point measurement methods. This advancement not only strengthens the scientific basis for the design of gradient coils but also provides more reliable parameters and methods for the accurate correction of MRI image distortions.
Magnetic Resonance Imaging/instrumentation* ; Humans ; Image Processing, Computer-Assisted/methods* ; Nonlinear Dynamics ; Magnetic Fields ; Algorithms ; Phantoms, Imaging

Nonunion of osteoporotic vertebral fractures (OVF), predominantly affecting the elderly, can lead to intractable pain, vertebral collapse, progressive kyphotic deformity, and neurological impairment, significantly compromising patients′ quality of life. There exists considerable debate on diagnosis and management of OVF, encompassing key issues such as clinical diagnosis and staging criteria for nonunion, surgical indications and procedure selection, and postoperative rehabilitation planning. Currently, there lacks standardized clinical guideline and expert consensus on the diagnosis and management of OVF nonunion in China. To address this gap, Minimally Invasive Surgery Group of Chinese Orthopedic Association, Osteoporosis Committee of Chinese Association of Orthopedic Surgeons, Prevention and Rehabilitation Committee for Osteoporosis of Chinese Association of Rehabilitation Medicine and Minimally Invasive Orthopedic Surgery Branch of China Association for Geriatric Care jointly organized domestic experts in spinal surgery, endocrinology, and rehabilitation to formulate the Clinical guideline for the diagnosis and treatment for nonunion of osteoporotic vertebral fractures ( version 2025), based on existing literature and clinical experience and adhering to principles of scientific rigor and practicality. The guideline provided 13 evidence-based recommendations encompassing diagnosis and treatment of OVF nonunion, aiming to standardize its clinical management.

Objective To observe the analgesic and rehabilitation effects of non μ-opioids anesthesia/analgesia(NΜOA)based on quadratus lumborum block(QLB)in emergency cesarean section under general anesthesia.Methods The retrospective study method was adopted,50 pregnant women undergoing hysterectomy under emergency general anesthesia in Langfang People's Hospital from January 2023 to December 2024 were selected as the study objects.The patients were divided into μ-opioids anesthesia/analgesia(ΜOA)group and NΜOA group according to different anesthesia/analgesia methods,25 cases in each group.ΜOA group received ΜOA;NΜOA group received NΜOA+QLB.Incisional pain and uterine contraction pain numerical rating scale(NRS)at out of the post-anesthesia care unit(T1),intravenous injection of oxytocin(T2),press the palace bottom 24 hours(T3),out of bed activity after operation(T4)and first analgesic time of incision pain,first analgesic time of uterine contraction pain,first no vomiting eating time,first exhaust time was observed and recorded.The incidence of vasoactive agents during the anesthetic period,rescue analgesia,rescue antiemetic,constipation,sleep disturbance after operation within 48 hours after operation were also recorded.Results The NRS scores at T1,T2,T3 and T4 in ΜOA group were significantly higher than those in NΜOA group(incisional pain 3.36±1.25 vs.1.12±0.97,3.68±1.18 vs.2.00±0.91,5.76±1.67 vs.4.20±1.00,4.48±1.29 vs.3.32±0.95;uterine contraction pain 3.72±1.49 vs.1.24±1.05,4.64±1.60 vs.3.04±1.27,7.56±1.71 vs.5.16±1.37,3.56±0.22 vs.2.56±0.16,all P<0.05).The first analgesic time of incision pain,first analgesic time of uterine contraction pain in ΜOA group were significantly less than that in NΜOA group(hours:3.06±2.02 vs.17.48±10.93,2.68±2.22 vs.15.80±11.39,both P<0.05),the first no vomiting eating time,first exhaust time in ΜOA group were significantly longer than those in NΜOA group(hours:8.56±0.57 vs.6.32±0.14,15.44±1.42 vs.10.16±1.14,both P<0.05),the incidence of vasoactive agents,rescue analgesia,rescue antiemetic,constipation,sleep disturbance after operation within 48 hours in ΜOA group were significantly higher than those in NΜOA group[64.0%(16/25)vs.32.0%(8/25),48.0%(12/25)vs.20.0%(5/25),44.0%(11/25)vs.16.0%(4/25),64.0%(16/25)vs.36.0%(9/25),60.0%(15/25)vs.32.0%(8/25),all P<0.05].Conclusion NΜOA based on QLB safely and effectively reduced side effects of μ-opioids and enhanced recovery compared to ΜOA on emergency cesarean section patients undergoing general anesthesia.

Objective:To investigate the application effect of quadratus lumborum block (QLB) combined with less opioid anesthesia analgesia in laparoscopic total hysterectomy (LTH) in elderly patients with uterine prolapse.Methods:A total of 86 elderly patients with uterine prolapse who received LTH in the Langfang People’s Hospital from Jan. 2021 to Oct. 2023 were prospectively selected and divided into group A ( n=42) and group B ( n=44) according to the random number table method. Group A received transversus abdominis block (TAPB) + general anesthesia, and group B received QLB combined with less opioid anesthesia + general anesthesia. The pain duration at different time points after operation [Numeric Rating Scale (NRS) method to evaluate resting incision and visceral pain] was compared between the two groups. The dosage of opioids and the additional analgesia rate were compared between the two groups. The sleep quality of the two groups before and 72 hours after operation was compared, and the adverse reactions of anesthesia were counted. Results:Compared with 6 h after operation, NRS scores of resting incision pain and visceral pain in the two groups decreased gradually at 12, 24 and 48 h after operation, and it was lower in group B than in group A. There were statistically significant differences between groups ( P<0.05) . Dosage of sufentanil and remifentanil in group B was lower than that in group A, and the postoperative additional analgesia rate in group B (9.09%) was lower than that in group A (28.57%) ( P<0.05) . 72 hours after surgery, the sleep efficiency and total sleep time of patients in both groups were lower than those before surgery, and they were higher in group B than in group A; The awakening time and number of awakenings in both groups were higher than those before surgery, while they were lower in group B than in group A ( P<0.05) . The total incidence of adverse reactions in group B was 4.76% (2/44) , lower than 23.81% (10/42) of group A ( P<0.05) . Conclusion:QLB combined with less opioid anesthesia analgesia can effectively reduce the degree of incision and visceral pain after LTH in elderly patients with uterine prolapse, reduce the amount of opioids used during operation and the rate of additional analgesia, and reduce the incidence of adverse reactions of anesthesia.

Objective:To investigate the application effect of quadratus lumborum block (QLB) combined with less opioid anesthesia analgesia in laparoscopic total hysterectomy (LTH) in elderly patients with uterine prolapse.Methods:A total of 86 elderly patients with uterine prolapse who received LTH in the Langfang People’s Hospital from Jan. 2021 to Oct. 2023 were prospectively selected and divided into group A ( n=42) and group B ( n=44) according to the random number table method. Group A received transversus abdominis block (TAPB) + general anesthesia, and group B received QLB combined with less opioid anesthesia + general anesthesia. The pain duration at different time points after operation [Numeric Rating Scale (NRS) method to evaluate resting incision and visceral pain] was compared between the two groups. The dosage of opioids and the additional analgesia rate were compared between the two groups. The sleep quality of the two groups before and 72 hours after operation was compared, and the adverse reactions of anesthesia were counted. Results:Compared with 6 h after operation, NRS scores of resting incision pain and visceral pain in the two groups decreased gradually at 12, 24 and 48 h after operation, and it was lower in group B than in group A. There were statistically significant differences between groups ( P<0.05) . Dosage of sufentanil and remifentanil in group B was lower than that in group A, and the postoperative additional analgesia rate in group B (9.09%) was lower than that in group A (28.57%) ( P<0.05) . 72 hours after surgery, the sleep efficiency and total sleep time of patients in both groups were lower than those before surgery, and they were higher in group B than in group A; The awakening time and number of awakenings in both groups were higher than those before surgery, while they were lower in group B than in group A ( P<0.05) . The total incidence of adverse reactions in group B was 4.76% (2/44) , lower than 23.81% (10/42) of group A ( P<0.05) . Conclusion:QLB combined with less opioid anesthesia analgesia can effectively reduce the degree of incision and visceral pain after LTH in elderly patients with uterine prolapse, reduce the amount of opioids used during operation and the rate of additional analgesia, and reduce the incidence of adverse reactions of anesthesia.

Objective To observe the analgesic and rehabilitation effects of non μ-opioids anesthesia/analgesia(NΜOA)based on quadratus lumborum block(QLB)in emergency cesarean section under general anesthesia.Methods The retrospective study method was adopted,50 pregnant women undergoing hysterectomy under emergency general anesthesia in Langfang People's Hospital from January 2023 to December 2024 were selected as the study objects.The patients were divided into μ-opioids anesthesia/analgesia(ΜOA)group and NΜOA group according to different anesthesia/analgesia methods,25 cases in each group.ΜOA group received ΜOA;NΜOA group received NΜOA+QLB.Incisional pain and uterine contraction pain numerical rating scale(NRS)at out of the post-anesthesia care unit(T1),intravenous injection of oxytocin(T2),press the palace bottom 24 hours(T3),out of bed activity after operation(T4)and first analgesic time of incision pain,first analgesic time of uterine contraction pain,first no vomiting eating time,first exhaust time was observed and recorded.The incidence of vasoactive agents during the anesthetic period,rescue analgesia,rescue antiemetic,constipation,sleep disturbance after operation within 48 hours after operation were also recorded.Results The NRS scores at T1,T2,T3 and T4 in ΜOA group were significantly higher than those in NΜOA group(incisional pain 3.36±1.25 vs.1.12±0.97,3.68±1.18 vs.2.00±0.91,5.76±1.67 vs.4.20±1.00,4.48±1.29 vs.3.32±0.95;uterine contraction pain 3.72±1.49 vs.1.24±1.05,4.64±1.60 vs.3.04±1.27,7.56±1.71 vs.5.16±1.37,3.56±0.22 vs.2.56±0.16,all P<0.05).The first analgesic time of incision pain,first analgesic time of uterine contraction pain in ΜOA group were significantly less than that in NΜOA group(hours:3.06±2.02 vs.17.48±10.93,2.68±2.22 vs.15.80±11.39,both P<0.05),the first no vomiting eating time,first exhaust time in ΜOA group were significantly longer than those in NΜOA group(hours:8.56±0.57 vs.6.32±0.14,15.44±1.42 vs.10.16±1.14,both P<0.05),the incidence of vasoactive agents,rescue analgesia,rescue antiemetic,constipation,sleep disturbance after operation within 48 hours in ΜOA group were significantly higher than those in NΜOA group[64.0%(16/25)vs.32.0%(8/25),48.0%(12/25)vs.20.0%(5/25),44.0%(11/25)vs.16.0%(4/25),64.0%(16/25)vs.36.0%(9/25),60.0%(15/25)vs.32.0%(8/25),all P<0.05].Conclusion NΜOA based on QLB safely and effectively reduced side effects of μ-opioids and enhanced recovery compared to ΜOA on emergency cesarean section patients undergoing general anesthesia.

Nonunion of osteoporotic vertebral fractures (OVF), predominantly affecting the elderly, can lead to intractable pain, vertebral collapse, progressive kyphotic deformity, and neurological impairment, significantly compromising patients′ quality of life. There exists considerable debate on diagnosis and management of OVF, encompassing key issues such as clinical diagnosis and staging criteria for nonunion, surgical indications and procedure selection, and postoperative rehabilitation planning. Currently, there lacks standardized clinical guideline and expert consensus on the diagnosis and management of OVF nonunion in China. To address this gap, Minimally Invasive Surgery Group of Chinese Orthopedic Association, Osteoporosis Committee of Chinese Association of Orthopedic Surgeons, Prevention and Rehabilitation Committee for Osteoporosis of Chinese Association of Rehabilitation Medicine and Minimally Invasive Orthopedic Surgery Branch of China Association for Geriatric Care jointly organized domestic experts in spinal surgery, endocrinology, and rehabilitation to formulate the Clinical guideline for the diagnosis and treatment for nonunion of osteoporotic vertebral fractures ( version 2025), based on existing literature and clinical experience and adhering to principles of scientific rigor and practicality. The guideline provided 13 evidence-based recommendations encompassing diagnosis and treatment of OVF nonunion, aiming to standardize its clinical management.

Objective:To investigate the application value of antegrade splenic superior region dissection first in laparoscopic total gastrectomy of obesity gastric cancer.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 21 obesity patients with gastric cancer who underwent laparoscopic total gastrectomy in Renji Hospital of Shanghai Jiaotong University School of Medicine from July 2018 to October 2023 were collected. There were 16 males and 5 females, aged (58±13)years. All 21 patients underwent laparoscopic total gastrec-tomy with antegrade splenic superior region dissection first. Observation indicators: operation time, volume of intraoperative blood loss, laparotomy conversion, intraoperative splenic hemorrhage or gastric hemorrhage, lymph node dissection, time to postoperative first flatus, time to postoperative initial liquid food intake, duration of postoperative hospital stay, postoperative complication. Measure-ment data with normal distribution were represented as Mean± SD, and count data were expressed as absolute numbers. Results:All 21 patients underwent laparoscopic total gastrectomy success-fully, with the operation time of (283±47)minutes, time for splenogastric ligament and vascular manage-ment of (34±12)minutes, volume of intraoperative blood loss of (143±86)mL, and no laparotomy conversion. There was no intraoperative splenic hemorrhage or gastric haemorrhage. The total number of lymph node dissected in 21 patients was 375, with the number of lymph node dissected as (21±9)per case. Time to postoperative first flatus, time to postoperative initial liquid food intake and duration of postoperative hospital stay in 21 patients were (3.1±0.7)days, (4.0±0.8)days and (10.1±3.0)days, respectively. There were 2 patients with postoperative complications, including 1 case of incision infection and 1 case of lung infection. The 2 patients with postoperative com-plications were recovered and discharged after conservative treatment. There was no death during the postoperative 30 days.Conclusion:The application of antegrade splenic superior region dissec-tion first in laparoscopic total gastrectomy is safe and feasible, which can reduce surgical difficulty.

Objective To study the effects of ultrasound-guided quadratus lumborum block(QLB)on intraoperative hemodynamics and opioid dosage in emergency patients with ectopic pregnancy.Methods A total of 70 patients with ectopic pregnancy undergoing laparoscopic surgery in Langfang People's Hospital from January 2021 to February 2024 were selected as subjects.According to the different anesthesia methods,the patients were divided into the control group and the study group,with 35 cases in each group.The control group was given general anesthesia,while the study group additionally added ultrasound-guided QLB.The intraoperative sedation effect,hemodynamics,postoperative pain,incidence of adverse reactions and opioid use at different times(admission,entry,intubation,skin incision,extubation,and discharge)were observed in the two groups.Results There were no statistically significant differences in the onset time of sedation,the rate of salvage sedation,the incidence of intraoperative body movements,the modified observer's assessment of alert/sedation(MOAA/S)at each time,and the hemodynamics at the time of admission,entry and intubation between the two groups.The mean arterial pressure(MAP),systolic blood pressure(SBP)and heart rate(HR)in the study group were significantly lower than those in the control group during skin incision,extubation and discharge[skin incision:MAP(mmHg,1 mmHg≈0.133 kPa)was 85.24±4.59 vs.96.95±4.68,SBP(mmHg)was 92.24±4.85 vs.99.49±5.13,HR(times/min)was 85.33±2.96 vs.94.51±2.92;extubation:MAP(mmHg)was 94.84±5.02 vs.102.05±5.13,SBP(mmHg)was 96.48±4.72 vs.105.03±5.07,HR(times/min)was 95.51±4.95 vs.102.49±5.87;discharge:MAP(mmHg)was 86.14±4.99 vs.93.71±5.25,SBP(mmHg)was 96.48±4.69 vs.104.37±5.02,HR(times/min)was 84.05±4.57 vs.90.51±4.86,all P<0.05]and pulse oxygen saturation(SpO2)was higher than those in the control group(skin incision:0.988 5±0.012 2 vs.0.965 4±0.012 3,extubation:0.974 7±0.012 4 vs.0.963 2±0.012 1,discharge:0.981 1±0.012 4 vs.0.970 3±0.012 3,all P<0.05).The resting numeric rating scale(NRS)scores and active NRS scores in the study group were lower than those in the control group at 3,6,12,and 24 hours after surgery,the random time was prolonged,the resting NRS and active NRS in the two groups gradually increased,reaching a peak at 24 hours after surgery,and the resting NRS and active NRS in the study group were significantly lower than those in the control group(resting NRS:3.86±0.82 vs.4.53±1.04,active NRS:4.26±1.05 vs.4.85±1.13,all P<0.05).The incidence of adverse reactions in the study group was lower than that in the control group[11.43%(4/35)vs.34.29%(12/35),P<0.05].The dosage of Sufentanil in 24 hours and 48 hours,the number of analgesic pump in 48 hours and the number of relief analgesia cases in the study group were lower than those in the control group[the dosage of Sufentanil in 24 hours(μg):23.28±4.02 vs.36.14±4.57,the dosage of Sufentanil in 48 hours(μg):41.61±4.82 vs.59.33±6.25,the number of analgesic pump in 48 hours(times):2.94±1.22 vs.6.15±1.71,the proportion of relief analgesia:8.57%(3/35)vs.28.57%(10/35),all P<0.05].Conclusion Ultrasound-guided QLB can reduce hemodynamic fluctuations,relieve postoperative pain,reduce adverse reactions and opioid use in emergency patients with ectopic pregnancy,demonstrating a positive impact.

Objective To observe the effect of quadratus lumborum block(QLB)anesthesia on intraoperative blood gas indexes and postoperative recovery in female uremic patients with peritoneal dialysis catheterization.Methods A total of 70 female uremic patients with peritoneal dialysis catheterization admitted to Langfang People's Hospital from January 2021 to December 2023 were selected as the research objects.According to the random number table method,they were divided into the control group and the study group,with 35 cases in each group.The control group was given conventional local infiltration anesthesia,whereas the study group was given QLB anesthesia.The changes of mean arterial pressure(MAP),heart rate(HR),blood gas indexes[pulse oxygen saturation(SpO2),arterial partial pressure of carbon dioxide(PaCO2)]and numeric rating scale(NRS)score,at different points pain factors[5-hydroxytryptamine(5-HT),substance P(SP),norepinephrine(NE)]before operation and 24 hours after operation,postoperative recovery(time to get out of bed for the first time,exhaust time,length of hospital stay)and adverse reactions were observed in the two groups.Results There was no significant difference in MAP,HR,blood gas index and NRS score between the two groups at the admission.The MAP,HR,PaCO2 in the study group were significantly lower than those in the control group during skin incision,rectus abdominis separation,catheterization,suture,and leaving the room,and SpO2 was significantly higher than that in the control group,and NRS score in the study group were significantly lower than those in the control group during skin incision,rectus abdominis separation,catheterization,suture(all P<0.05).There was no significant difference in the levels of 5-HT,SP and NE between the two groups before operation,but the levels of 5-HT,SP and NE at 24 hours after operation were significantly higher than those before operation,but the levels of 5-HT,SP and NE in the study group were lower than those in the control group.The first ambulation time,exhaust time and hospitalization time in the study group were significantly shorter than those in the control group(all P<0.05).The incidence of nausea and vomiting,constipation,pruritus,dizziness and other adverse reactions in the study group was significantly lower than that in the control group(all P<0.05).Conclusion QLB can reduce the fluctuation of intraoperative blood gas indexes in female uremic patients with peritoneal dialysis catheter,relieve postoperative pain,reduce the level of pain factors and reduce the occurrence of adverse reactions,and has a good effect on promoting postoperative recovery of patients.