[The clinical effect and imaging features of accordion maneuver in promoting bone healing at the docking site after tibial transport under ultrasonic monitoring].

Objective: To explore the imaging features and clinical effect of accordion maneuver in promoting the bone healing at the docking site after tibial transport under ultrasonic monitoring. Methods: Retrospective analysis was conducted on the clinical data of 16 patients with tibial bone transport who were admitted to the Department of Orthopedics, the second Hospital of Shanxi Medical University from May 2018 to October 2019. All the patients were treated with accordion maneuver to promote bone healing at the docking site under ultrasound monitoring. There were 14 males and 2 females, aged (45.3±14.3) years (range: 6 to 61 years). Before tibial bone transport, the length of the tibial defect of 16 patients was (6.0±2.6) cm (range: 2.0 to 12.1 cm). The operation steps of accordion maneuver were as follows: pressurization for 2 weeks, suspension for 12 days, distraction for 2 weeks, retraction for 2 weeks, and then stop the operation to consolidate the bone mineralization. During accordion treatment, ultrasound was used to monitor the size of hematoma, Adler grade of blood flow signal and the changes of new callus in and around the docking site. X-ray was performed to monitor bone healing at the docking site. Pearson correlation coefficient was used to analyze the correlation between the size of hematoma, the resistance index of blood flow signal and the bone healing time of the docking site. Paley healing criterion was used to evaluate the bone healing and functional recovery of the patients. Results: During accordion maneuver, ultrasound examination showed that the Adler grade of blood flow signals around the docking site increased gradually before retraction and then decreased gradually, but the degree of callus mineralization continued to increase gradually. After 2 weeks of pressure on the docking site, hematoma was observed in 14 patients by ultrasound examination. X-ray showed that all docking sites had bony healing, with the healing time of (30.8±4.9) weeks (range: 23 to 40 weeks).The size of the hematoma was negatively correlated with the healing time of the docking site (r=-0.819,P<0.01). No hematoma was found in 2 patients, and after continuous observation for 20 weeks, there was still no obvious callus connection at the docking site. After bone cortical removal, ultrasound examination showed hematoma formed at the docking site. Accordion maneuver was continued, and the docking site healed at 30 and 32 weeks after surgery, respectively. There was a negative linear correlation between hematoma size at 2 weeks of compression and the blood flow resistance index at 2 weeks of retraction in 16 patients (r=-0.801, P<0.01). The patients were followed-up for (14.5±3.2) months (range: 10.6 to 20.2 months). At the last follow-up, 12 patients were evaluated as excellent and 4 were evaluated as good by Paley healing criteria. Conclusion: The distraction and compression stress applied in accordion maneuver can promote bone healing at the docking site, and ultrasound can monitor early signs of bone healing at the docking site to help determine the tendency of bone healing.

[Correlation between total cerebral small vessel disease score and retinal vessel diameters in patients with mild stroke].

Objective: To explore the relationship between the total cerebral small vessel disease (CSVD) score and retinal vessel diameters in patients with mild stroke. Methods: The patients with mild stroke who were hospitalized in the Second People's Hospital of Changzhou, Nanjing Medical University from March to December 2019 were continuously collected (National Institutes of Health Stroke Scale score≤3 points). All patients completed the head magnetic resonance imaging and retinal fundus photography examination, and then the retinal arteriovenous diameter was measured semi-automatically based on the pictures. According to the total CSVD score (0-4 points), the patients were divided into 5 groups. The baseline characteristics of the patients were compared. Moreover, the correlation of total CSVD with retinal blood vessel diameters were analyzed by spearman and linear regression. Results: A total of 206 patients were enrolled. There were 69, 51, 41, 30, and 15 patients with 0, 1, 2, 3, and 4 points, respectively. In CSVD subgroups, there were significant differences in age, duration of hypertension and diabetes (all P<0.05). The central retinal artery equivalent (CRAE), (CSVD scores 0-4 were (126±12) µm, (118±11) µm, (108±11) µm, (99±8) µm, (90±7) µm, P<0.001) and arteriole-to-venule ratio (AVR) (CSVD scores 0-4 were 0.65±0.05, 0.60±0.04, 0.56±0.04, 0.49±0.03, 0.44±0.02, P<0.001) were different in CSVD subgroups. With the increase of CSVD score, the diameter of artery and AVR became smaller. The total CSVD was significantly correlated with AVR by Spearman correlation analysis (r= 0.818, P<0.001). By constructing a linear regression equation model, the coefficient of determination of the total CSVD score (R2=0.694) was higher than that of lacunes, white matter hyperintensities, cerebral microbleeds and enlarged perivascular space. After adjusting for age, course of hypertension and diabetes, and different types of CSVD, further multiple linear regression analysis revealed that the total CSVD score was still an independent related factor of AVR (ß=-0.039, P<0.001, 95%CI=-0.051--0.028). Conclusions: Total CSVD score is negatively correlated with retinal artery diameters and AVR. Additionally, the total CSVD score can better reflect the degree of cerebral microvascular lesions than single type CSVD.

Salient space detection algorithm for signal extraction from contaminated and distorted spectrum.

An algorithm for signal extraction from a contaminated and distorted spectrum is proposed. First, this algorithm combines the salient space of the spectrum and the statistical characteristics of the noise to detect signal regions at different scales. Second, it extracts signals by subtracting the baseline from the spectrum in the signal regions. The baseline is fitted by segmented polynomial functions. This algorithm has been applied to simulated and experimental data, and the results show that this algorithm can accurately and automatically extract signals with varying widths from a contaminated spectrum. This method minimizes the influence of baseline distortion and exhibits good anti-noise capability and high real-time performance.

[Clinical outcomes of single-level lumbar spondylolisthesis by minimally invasive transforaminal lumbar interbody fusion with bilateral tubular channels].

Objective: To evaluate the clinical effectiveness of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for single-level lumbar spondylolisthesis treatment with bilateral Spotlight tubular channels. Methods: A total of 21 patients with lumbar spondylolisthesis whom underwent MIS-TLIF via bilateral Spotlight tubular channels were retrospectively analyzed from October 2014 to November 2015. The 21 patients included 11 males and 10 females ranged from 35 to 82 years (average aged 60.7 years). In term of spondylolisthesis category, there were 18 cases of degenerative spondylolisthesis and 3 cases of isthmic spondylolisthesis. With respect to spondylolisthesis degree, 17 cases were grade Ⅰ° and 4 cases were grade Ⅱ°. Besides, 17 cases at L(4-5) and 4 cases at L(5)-S(1)were categorized by spondylolisthesis levels. Operation duration, blood loss, postoperative drainage and intraoperative exposure time were recorded, functional improvement was defined as an improvement in the Oswestry Disability Index (ODI), Visual Analog Scale (VAS) was also employed at pre and post-operation (3 months and the last follow-up), to evaluate low back and leg pain. Furthermore, to evaluate the recovery of the intervertebral foramen and of lumbar sagittal curvature, average height of intervertebral space, Cobb angles of lumbar vertebrae and operative segments, spondylolisthesis index were measured. At the last follow-up, intervertebral fusion was assessed using Siepe evaluation criteria and the clinical outcome was assessed using the MacNab scale. Radiographic and functional outcomes were compared pre- and post-operation using the paired T test to determine the effectiveness of MIS-TLIF. Statistical significance was defined as P<0.05. Results: All patients underwent a successful MIS-TLIF surgery. The operation time (235.2±30.2) mins, intraoperative blood loss (238.1±130.3) ml, postoperative drainage (95.7±57.1) ml and intraoperative radiation exposure (47.1±8.8) were recorded. Different significance between 3 months post-operative follow-up and pre-operation was exhibited (P<0.01) in respects of lumbar VAS (t=11.1, P<0.01) and leg VAS (t=17.8, P<0.01). Moreover, final follow-up compared with pre-operation, and final follow-up compared with 3 months post-operative follow-up, VAS scores were also statistical difference (P<0.01). At the final follow-up, there were significant differences compared with pre-operation in ODI scores (t=30.1, P<0.01). Comparison between 3 months post-operative follow-up and pre-operation, statistical distinctions were demonstrated (P<0.05) in terms of mean height of intervertebral space (t=-10.9, P<0.01), the Cobb angles of lumbar vertebrae (t=-2.4, P<0.05), operative segments Cobb angles (t=-5.2, P<0.01) and Lumbar spondylolisthesis incidence (t=17.1, P<0.01). In addition, there was statistical difference between final follow-up and pre-operation (P<0.05) as well. For instance, mean height of intervertebral space (t=-10.5, P<0.01), the Cobb angles of lumbar vertebrae (t=-2.7, P<0.05), operative segments Cobb angles (t=-4.2, P<0.01) and Lumbar spondylolisthesis incidence (t=18.6, P<0.01) were involved. All spondylolisthesis vertebrae were restored completely. Lastly, at the last follow-up, 12 cases of grade 1 and 7 cases of grade 2 fusion were present as determined by the Siepe evaluation criteria. McNab scale assessment classified 17 patients having excellent clinical outcome, 3 patients in good and 1 patient having a better clinical outcome. Conclusion: MIS-TLIF with bilateral Spotlight tubular channels is a safe and effective approach for single segment lumbar spondylolisthesis.

The correlation between vertebral wedge-shaped changes in X-ray imaging at supine and standing positions and the efficacy of operative treatment of thoracolumbar spinal fracture in the elderly.

STUDY DESIGN: By analyzing a large number of surgical patients, we identified the roles of wedge-shaped changes in related surgeries. OBJECTIVES: To illustrate the relevance of vertebral wedge-shaped changes in X-ray imaging at supine and standing positions in patients with percutaneous kyphoplasty as well as the postoperative effect. SETTING: All patient data were collected from a hospital in China. METHODS: Between June 2006 and May 2010, 77 surgical patients (9 men and 68 women) with wedge-shaped compression fractures were retrospectively analyzed. Patients were divided into group A (ΔWR2.5%) and group B (ΔWR<2.5%) according to the dynamic changes in the percentage of vertebral body wedge-shaped variable ratio (WR) at supine and standing positions. The intensity of back pain in different positions pre- and postoperatively was evaluated with a visual analog pain scale (VAS). RESULTS: The WRs in both standing and supine positions were significantly reduced by kyphoplasty in both groups A and B. In agreement with the improvement in WRs, the VAS was significantly decreased in three positions for patients in group A and in turning over and standing position for patients in group B. With respect to ΔWR changes, group B revealed significantly lower values compared with group A preoperatively (P<0.001), but there was no significant difference between groups A and B postoperatively and at 1-month follow-up (P=0.179 and P=0.558, respectively). CONCLUSIONS: Improvement in symptoms after kyphoplasty is better in patients with wedge-shaped changes in supine and standing positions, and the efficacy of height restoration of the spine would be better in unstable vertebrae by balloon dilatation.

Intestinal absorption mechanisms of ginsenoside Rh2: stereoselectivity and involvement of ABC transporters.

This study investigated the absorption mechanism of ginsenoside Rh2 to clarify the reasons for its poor absorption. Transepithelial transport across Caco-2 cell monolayers, cellular uptake, and in situ rat intestinal perfusion were examined. Cellular uptake of Rh2 was linear from 1 to 50 µM at 4°C, whereas it was saturated when the concentration exceeded 10 µM at 37°C. At 37°C, the uptake at 10 µM was linear in 60 min. Intracellular exposure in 240 min was 2173.70 and 979.38 ng·min/µg for S and R isomers, respectively. Transepithelial permeability of Rh2 was about 10⁻8 to 10⁻7 cm/s. Efflux ratios were above 1.5. Sodium dodecyl sulfate, sodium citrate, and sodium deoxycholate had no effect on Rh2 permeability. After intestinal perfusion for 3 h, 9.1% of 20(R)-Rh2 and 15.7% of 20(S)-Rh2 were absorbed. Cyclosporine, quercetin, and probenecid could improve the cellular uptake, absorptive permeability, and intestinal absorption. Carrier-mediated transport was the major absorption mechanism. Rh2 was a substrate of ABC transporters. The ABC-transporter-mediated efflux and the poor permeability were the major reasons for Rh2 poor absorption. The stereoselective absorption was significant. R isomer exhibited lower absorption profiles in all the experiments, possibly due to more potent efflux.