Objective To employ spinal virtual surgery system (SVSS) for preoperative planning of thoracolumbar pedicle screw fixation, and to establ ish the measurement method for pedicle screw-related parameters. Methods Eight thoracicand lumbar spine specimens (T11-L3) were selected. First of all, SVSS was used for the preoperative planning of pedicle screw and the parameters of both sides of pedicle were measured in every vertebral segment, including angle of axial view (Aa), angle of sagittal view (As), x-direction entrance (XE), total pedicle length of axial view (TLa), total pedicle length of sagittal view (TLs), pedicle height (PH), pedicle width (PW), and pedicle spongy width (PSW). Then the corresponding parameters of the right and left pedicle screws of the specimens were measured actually. Finally, its accuracy was verified by comparing the data by virtual measurement and actual measurement. Results There was no significant difference in the parameters of virtual measurement (Aa, As, TLa, TLs, XE, PW, PSW, and PH) and actual measurement (Aa, As, TLa, XE, PW, PSW, and PH) between the right and left sides (P gt; 0.05). Except XE of the L3 vertebral segment and PSW of T11 and T12 vertebral segments (P lt; 0.05), the differences in other parameters of other segments were not significant (P gt; 0.05). Conclusion After statistical analysis and comparison, the feasibil ity of preoperative planning of thoracolumbar pedicle screw fixation and the accuracy of the measurement of the SVSS is verified.
Objective To discuss the diagnosis and treatment of posterolateral corner injury of the knee joint, and to evaluate the clinical results after anatomical reconstruction. Methods Sixteen cases of posterolateral cornerinjury of the knee were treated, being accompanied with grade Ⅲ or above existing serious varus or external rotation. At a mean follow-up of 13 months(7 to 18 months),weevaluate the clinical results using Lysholm and IKDC(international knee documentation committee) scoring systems. Among them,there were 14 males and 2 females aging 19-46 years (mean 38 years). It was 4-12 d from injury to operation. On conditions of anesthesia, varus stresstest(VST) showed that instability of varus was more than 10° under the 30° and 0° of genuflexion respectively and external rotation test showed that instability of external rotation was more than 10° when compared with normal side. Five cases complicated by rupture of anterior cruciate ligament,8 cases by rupture of posterior cruciate ligament and 3 cases by rupture of both ligaments. Results All patients were followed 7 to 18 months and no patients had instability of the knee. The VST showed that no abnormal lateral instability was found at 0° of flexion except 3 cases at 30° with less than 5°. Cooper test showed that no rotational instability at 90° except 1 cases at 30° with less than 5°. The range of motion of the knee was from 75° to 130° of flexion(mean 118°)and from 0° to 5° of extension. Posteroperative scores were from 54 to 96 according to Lysholm scoring systems and from 46 to 94 according to IKDC scoring systems. Conclusion Although the overall incidence of posterolateral corner injury is less than that of other ligament injuries of the knee, we should pay much attention to posterolateral corner injury because of its important role in resisting posterior tibia translation,external rotation and varus of knee. This injury can result in a significant degree of disability for patients.
We have tried to explore the energy loss (EL) within the left ventricle in hypertension by using vector flow mapping (VFM) to detect left ventricular hemodynamic changes in hypertensive patients as early as possible and reflect changes of left ventricular function in hypertension by using EL. Twenty-one hypertensive patients with increased left ventricle mass index (LVMI), 14 hypertensive patients with normal LVMI and 22 control subjects were enrolled in this study. Systolic and diastolic EL derived from VFM within the left ventricle and E/e' by dual Doppler were recorded and analyzed. Compared with those of the controls, diastolic and systolic EL were significantly increased in hypertensive group (P<0.05). In diastole, EL=0.439×SBP (systolic blood pressure)–8.349; in systole, EL=0.385×SBP+0.644×LVMI–10.854. And the EL was positively correlated with E/e', but there was no significant correlation between EL and ejection fraction (EF) in the pooled population. The study shows that the increased EL can help us detect changes of left ventricular hemodynamic in hypertensive patients. It needs further investigation to prove whether EL within the left ventricle could be a new parameter to evaluate diastolic function. SBP and LVMI are the independent predictors for systolic EL, while SBP is the independent predictor for diastolic EL.
ObjectiveTo compare the X-ray projection doses during leadless pacemaker implantation and conventional single chamber ventricular pacemaker (VVI) implantation. MethodsThis study included all patients who underwent leadless pacemaker implantation and VVI pacemaker implantation performed by the same principal investigator team using the same digital subtraction angiography (DSA) machine in the West China Hospital of Sichuan University from August 3rd, 2018 to February 18th, 2020. Among the enrolled patients, 27 who underwent leadless pacemaker implantation were included in the case group, whereas 38 who underwent conventional VVI implantation were included in the control group. Data regarding the intraoperative dose area product (DAP), air kerma (AK), duration of X-ray fluoroscopy, number of exposed sequences on the film, total number of frames on the film, operation time, and BMI were collected to investigate the causes of the differences. ResultsThe case group received a higher X-ray projection dose than the control group, and there were statistically significant differences between the two groups in terms of DAP, AK, duration of X-ray fluoroscopy, the number of exposed sequences on the film, the total number of frames on the film, and operation time (P<0.05). ConclusionPatients who underwent leadless pacemaker implantation are exposed to more radiation than those who underwent conventional VVI implantation.
We tried to explore the value of contrast echocardiography (CEcho) on evaluating hypertrophic cardiomyopathy (HCM) with the inferior wall hypertrophy. A total of 114 patients with HCM were investigated. All the patients received CEcho and routine echocardiography (Echo), and 45 of them received cardiac magnetic resonance (CMR) and 47 of them received Holter. The frequency and percentage of inferior wall hypertrophy were analyzed in HCM patients, as well as the structure and function. The results showed that: (1) Inferior wall hypertrophy was detected in 55 patients (48%) by Echo, while 68 patients (60%) by CEcho. (2) There was no significant difference between CMR and CEcho in the measurement of inferior wall at end-diastole and end-systole. Thickness of inferior wall by CEcho tended to be higher than CMR. However, the inferior wall thickness measured by Echo was obviously lower than that by CMR (P < 0.05) and CEcho ( P < 0.05). (3) Bland-Altman plot suggested good consistency between CEcho and CMR in measuring inferior wall thickness. 95% CI of mean differences in inferior wall thickness between CEcho and CMR were smaller in HCM patients as compared with that between Echo and CMR. Unary linear regression analysis showed good degree of fitting between CEcho and CMR. (4) Holter showed that HCM patients with inferior wall hypertrophy were likely to have higher incidence of premature ventricular complexes (PVC) ≥ 500/24 h. We demonstrate that CEcho is rather sensitive in detecting inferior wall hypertrophy. Echo may underestimate the inferior wall thickness. The risk of ventricular premature beats may increase in HCM patients with inferior hypertrophy.
This study aims to explore the intraventricular pressure difference (IVPD) within left ventricle in patients with paroxysmal atrial fibrillation (PAF) by using the relative pressure imaging (RPI) of vector flow mapping (VFM). Twenty patients with paroxysmal atrial fibrillation (PAF) and thirty control subjects were enrolled in the study. Systolic and diastolic IVPD derived from VFM within left ventricle and conventional echocardiographic parameters were analyzed. It was found that the B-A IVPD of left ventricle in PAF patients showed the same pattern as controls—single peak and single valley during systole and double peaks and double valleys during diastole. Basal IVPD was the main component of base to apex IVPD (B-A IVPD). The isovolumetric systolic IVPD was associated with early systolic IVPD, early systolic IVPD was associated with late systolic IVPD, and late systolic IVPD was associated with isovolumic diastolic IVPD (all P < 0.05). The B-A IVPD and basal IVPD during isovolumetric systole, early systole, late systole and isovolumetric diastole in PAF patients significantly decreased (all P < 0.05). The study shows that the B-A IVPD pattern of the PAF group is the same as controls, but systolic B-A IVPD and basal IVPD are significantly reduced in PAF patients. VFM-derived RPI can evaluate left ventricular IVPD in PAF patients, providing a visually quantitative method for evaluating left ventricular hemodynamic mechanics in the patients with PAF.
Objective To investigate the correlation between dynamic intrinsic positive endexpiratory pressure ( PEEPidyn) and volume dependence of elastance and resistance of respiratory system ( Evd/Rvd) derived from nonlinear analysis of respiratory mechanics in COPD patients during pressure support ventilation ( PSV) . Methods Twenty-five COPD patients mechanically ventilated using mode of PSV were ventilated at a PSV level of no less than 20 cm H2O in a period of 15 minutes to attain so-callednear-relaxation state. The pressure( P) , flow( V′) and volume( V) data were analyzed by nonlinear mode of respiratory motion. PEEPidyn was determined by esophageal balloon-tipped catheter technique. The correlations between PEEPidyn and Evd, Rvd as well as Evd ×Rvd were analyzed. Results The correlation coefficients between PEEPidyn and Evd, Rvd as well as Evd ×Rvd were 0. 85,0. 80, and 0. 90, respectively. Conclusions Nonlinear mode of respiratory motion is suitable to analyze respiratory mechanics of COPD patients mechanically ventilated using mode of PSV. There are good correlations between PEEPidyn and Evd,Rvd as well as Evd ×Rvd which may be used to noninvasively monitor PEEPidyn in mechanically ventilated COPD patients using mode of PSV.
Objective Methylprednisolone (MP) is the only active drug for acute spinal cord injury (SCI), but the molecular mechanism is still further studied. To investigate the pathophysiology of SCI and the molecular mechanism of MP in treating SCI. Methods Nine rabbits were randomly divided into 3 groups, weighing (3 100 ± 140) g: sham operation group(group A, n=3), model group (group B, n=3), and drug treatment group (group C, n=3). After laminectomy was performed in3 groups, no treatment was given in group A, and the model of SCI was establ ished with modified Allen’s fall ing strike method in groups B and C at L4; then high-dose MP equivalent with human dose was adopted in group C at 2 hours after SCI and the normal sal ine in group B. All rabbits were sacrificed at 8 hours after SCI, and then the spinal cord tissues about 8 mm long which included the injuried site were obtained. Total RNA was isolated with Trizol one-step method to examine the gene expression profile by using Ogl io technologies with standard operating procedures and qual ity control as recently described respectively. GeneSpring11.0 analyzer software was used to filter potential candidate genes for statistical significance using Welch’s t test, and only genes with P lt; 0.05 and fold change (FC) ≥ 2 were retained for further analysis. Some differentially expressed genes were also verified by RT-PCR to ensure the rel iabil ity of microarray results. Results The SCI model was set up and the samples of spinal cord tissues were acquired successfully at 8 hours after SCI. The qual ify of total RNA from each group met the requirement for the microarray examination and data analysis. These differentially expressed genes involved inflammation, immunity, ion transportation, transcription factors, and so on. The results of genes IL-1α, IL-1β, and defensin 4 (NP-4) by RTPCR were consistent with that of gene-chips. The immuno-related genes included NP-3, NP-4, corticostatin 6, CAP-18, and antimicrobial peptide, which displayed obvious differential expression. Conclusion High-dose MP has protective effects on nervous function by the immunity mechanism, and the main effector may be neutrophil.
Objective To assess the cl inical significance of transpedicular screw insertion in lower cervical vertebra assisted by multi-spiral CT (MSCT) three dimentional (3D) image reconstruction techniques. Methods Eight cervical vertebra specimens were examined by MSCT, and the messages were sent to SGI02 Workstation; according to the parameter requirements of lower cervical pedicle fixation, by using post-process of volume rendering (VR) the condition was judged and multi-plannar reformation (MPR) was used to do individual analysis; and the ideal path of screw insertion was obtained andthe related parameters were measured. After preoperative plan being finished, referring to these measured parameters, 3.5 mm screws were inserted into C3-7 pedicles of these 8 specimens. After insertion of screws, MSCT scanning and 3D reconstruction were performed again to evaluate the accuracy of lower cervical pedicle screw inserting. From May 2007 to November 2009, 28 patients who received screw insertion in lower cervical spines were given MSCT scanning and 3D reconstruction to evaluate the illness situation, to confirm shortest fixation volumes, and to collect the parameters of aim pedicle screw insertion. Results The time of insertion for each screw was (392 ± 62) seconds. It was found that one pedicle was clausura (1.25%, 1/80) and five pedicle diameters in coronal view were less than 3 mm (6.25%, 5/80), which all were not fit for screw insertion. A total of 74 screws were placed successfully. One-time success rate of screw insertion was 95.95% (71/74). The total accuracy rate was 91.89% (68/74). Six screws penetrated (8.11%). According to the Richter penetrating classification: grade one was 6.76% (5/74) and grade two was 1.35% (1/74). There were significant differences (P lt; 0.05) in penetrated rate between our study and anatomic landmark local ization (47.37%), Miller methods (25.00%), and there was no significant difference (P gt; 0.05) when compared with Abumi method (6.70%), hopper method (7.10%), pipel ine deoppilation method (5.20%) and navigation technique (11.30%). In cl inical 28 cases, 121 screws were inserted; one pedicle was clausura and one was fissure fracture, which all were unfit for insert screw in preoperative plan, the surgery project was adjusted. After operation, 17 patients (76 screws) were given MSCT scanning again. A total of 67 screws (88.16%) were placed successfully. Nine screws (11.84%) penetrated, grade one was 7.89% (6/76) and grade two was 3.95% (3/76). Conclusion It is accurate to apply MSCT 3D reconstruction techniques to measure the ideal screw canal in preoperative individual ized plan. Strictly following individual quantitative data, the safety and accuracy of the surgery can be improved. And it is feasible and available to use MSCT MPR imaging to evaluate the accuracy of pedicle screw insertion.
ObjectiveTo analyze systematic reviews (SRs) and meta-analyses on the efficacy of pharmacological interventions in the prevention of contrast-induced acute kidney injury (CI-AKI) after percutaneous coronary intervention (PCI). MethodsWe searched the PubMed, The Cochrane Library, EMbase, CNKI, CBM, WanFang Data, and VIP databases to identify SRs and meta-analyses on the pharmacological interventions aimed at preventing CI-AKI after PCI from inception of the databases to February 2022. Two researchers independently screened the literature and extracted data. The PRISMA statement, AMSTAR 2 tool, and GRADE system were adopted to evaluate the reporting quality, methodological quality, and evidence quality of the findings of the included SRs and meta-analyses. ResultsA total of 14 SRs and meta-analyses were identified. Among the drugs used were statins, N-acetylcysteine, sodium bicarbonate, Dan-hong injection, vitamins, salvianolate, adenosine antagonists, nicorandil, allopurinol, alprostadil, furosemide, trimetazidine, probucol, and brain natriuretic peptide. Most of the studies had relatively comprehensive coverage of the items, with the PRISMA scores ranging from 18 to 24.5. The main issues of reporting quality were protocol and registration, search, and funding. The methodological quality of the SRs and meta-analyses was generally low. Items 2 and 7 were the key items with poor scores, and the non-critical items with poor scores were items 3, 10, and 16. All drugs, except furosemide, decreased the incidence of CI-AKI. The quality of evidence ranged from medium to very low according to GRADE. Conclusion Most of the single drugs or drugs combined with hydration show the potential to prevent CI-AKI, however, the overall methodological quality of the included studies is relatively low, and the strength of evidence is generally low.