BACKGROUND:The existing bone grafting apparatus are al long tubular-shape, antegrade bone grafting; however, the bone grains within the tube were difficult to put through, along with large bone loss. OBJECTIVE:To design a new concept of minimaly invasive bone grafting apparatus, so as to achieve the minimaly invasive bone grafting in vertebral body and intervertebral space. METHODS: On Solidworks 2012 software platform, the 3D three-dimensional solid modeling technology was employed to design a new concept of gun-shape bone grafting device with the characteristics of headend reversely placing at the grafting position and antegrade pushout, against the problems such as antegrade bone grafting, long bone grafting path and difficulty in bone grafting existing in precious percutaneous or/and transpedicular bone graft apparatus. The virtual assembly and simulative bone grafting surgery were performed with the bone grafting apparatus for observation of the instrument matching degree and grafting surgical procedures. RESULTS AND CONCLUSION: A set of minimaly invasive gun-shape bone grafting apparatus was successfuly designed; its length was 20 cm in total; the length of the front semi-closed bone tube was 2.5 cm. There are two kinds of diameter specifications: inner diameter of 3.5 mm/outer diameter of 4 mm, and inner diameter of 5 mm/outer diameter of 6 mm. Virtual assembly revealed that the grafting apparatus were wel matched. Stimulative surgery displayed that the bone grain loading and launch were simple. The gun-shape bone grafting device is reasonable in design, avoiding pushing too long distance, bone pushing difficulties, bone loss and other problems in previous tubular bone grafting apparatus. Percutaneous, endoscopic vertebrae or intervertebral space minimaly invasive bone grafting can be performed with this apparatus.

Objective To observe left ventricular transmural peak radial strain and strain time-to-peak of peri-infarct different layers myocardium using tissue Doppler strain imaging, to assess its mechanical pattern during acute myocardial ischemia.Methods Left anterior descending coronary artery (LAD) were ligated in experimental open-chest Beagle dog models (n = 9),the two-dimensional apical short-axis views of left ventricle in three complete cardiac cycles were acquired and stored in TDI-Q workstation at baseline(the control group of peri-infarc myocardium) and during acute myocardial ischemia respectively.Sampling volume was uesd to measure the peak radial strain and the strain time-to-peak consesquently on the derived M -mode tissue Doppler velocity images at peri-infarct myocardium before and after ischemic segments and different layers(subendocardium, medium, subepicardium).Statistical analies was performed using student's t- test or Pearson's correlations.Results Peak radial strain decreased at peri-infarct subendoeardium (P<0.05) with no significant difference between those at baseline and at peri-infarct medium (P >0.05), the peak radial strain increasd at peri-infarct subepieardium (P < 0.05) ,and the strain time-to-peak at different layers of peri-infarct myoeardium was significantly postponed (P< 0.05).There was a good correlationship of peak radial strain between subendocardium and segment as well as between the medium and segment (r = 0.617, P<0.01 ; r = 0.556, P<0.01).This correlationship disappeared at peri-infarct myocardial segment (r = 0.287, P > 0.05, r = 0.243, P > 0.05).Conclusions The left ventricular transmural mechanical remodeling at peri-infarct myocardium is the integrant of result of mechanical interactions between ischemic and nonischemic myocardium,which might be one of the trigger the structural and fundational remodeling processes involving in the pathophysiological foundation of ischemie cardiomyopathy.

Objeetive To analyze the causes and to explore prevention and management of bile leakage after laparoscopic common bile duct exploration with choledochoscopy followed by primary suturing of choledochal incision.Methods The clinical data of 52 patients with bile leakage after laparoscopic common bile duct exploration choledochoscopy and primary suturing of choledochal incision carried out for choledocholithiasis between June 2011 to June 2013 were retrospectively studied.Results All the 52 patients successfully underwent the laparoscopic surgery and left hospital.The operation time was (101 ± 26) minutes (range 55～ 145 minutes).The intraoperative blood loss was (36±28) ml (range 10～ 100 ml).All the patients were ambulatory after the first postoperative day.The recovery time of postoperative gastrointestinal function was (49.8 ± 12.5) hours (range 37 ～ 74 h).The total hospitalization time was (10.8 ± 2.5) days (range 7 ～ 15 days).The average hospitalization days after surgery was (5.7 ± 1.7) days.The average hospitalization cost was (24 827 ± 3 776) yuan.There were two patients who developed intraoperative bile leakage which was treated with further suturing.Five patients developed postoperative bile leakage and they were cured after unobstructed drainage for 5 days through conservative treatment.After a follow-up of 1 ～ 2years,there was no recurrent lithiasis.The stone clearance rate was 100％.There was no bile duct stricture or other complications.Conclusion In expert hands and with proper selection of patients,laparoscopic common bile duct exploration,choledochoscopy and primary suturing of choledochal incision were safe,effective and feasible for choledocholithiasis.

Objective:To compare the efficacy and safety between cryoablation(Cryo)and radiofrequency (RF)ablation in patients with atrioventricular nodal reentrant tachycardia(AVNRT). Methods: A total of 83 patients with AVNRT underwent electrophysiological treatment in our hospital from October 2006 to March 2009 were studied. Patients were divided into two groups according to their own choices. Cryo group (n=41) and RF group (n=42). The clinical characteristics,success rate,procedural time and ablative time were compared between two groups. Results:The procedural time and ablative time in Cryo group was significantly longer than those in RF group (119.14±40.16 min vs.85.86±28.24 min,P=0.001; 1118.91±620.62 s vs.370.97±279.23 s,P<0.001). The acute success rate was achieved in 40/41(97.6%)patients in Cryo group,and 42/42(100.0%) in RF group. Transient AV-block was encountered in 6 (15%) patients in the Cryo group and 5 (11.9%) in RF group (P=0.681). There was no complete atrial-ventricular(AV)conduction block at the end of procedures. There was no recurrence of AVNRT in either Cryo group nor in RF group during 11.6±5.5 months of follow up period.Conclusion:Cryoablation was as effective and safe as RF ablation for AVNRT. Cryo-energy was one kind of alternative ablation energy for AVNRT.

Objective To assess subendocardial systolic circumferential strain(CS),radial strain(RS)and radial displacement(RD)of left ventricle(LV)in short-axis view and LV global systolic function in open-chest canine model with acute myocardial ischemia using velocity vector imaging(VVI),and to establish their spatial correlationships.Methods Left anterior descending coronary artery(LAD)was ligated for 20 minutes to induce acute myocardial ischemia in 12 open-chest canine model.At baseline and 20 minutes after ischemia,two-dimensional dynamic gray-scale images of three standard left ventricular short-axis views at the levels of mitral annulus,papillary muscle and apex and the images of LV apical fourchamber and two-chamber view were acquired and transfefred to VVI workstation for off-line analysis.Peak systolic CS,RS and RD of eighteen segments and of three global short-axis sections of LV were measured at subendocardium.and LV ejection fraction(LVEF)and stroke volume(SV)were calculated using Simpson's method.The differences and correlationships were analyzed between them.Resuls Compared with the value at baseline,LVEF decreased significantly(P＜0.05)after ischemia.The peak systolic subendocardial CS,RS and RD of the affected segments,global CS,RD at papillary muscle and apex views and global RS at apex view were significantly lower than those at baseline after ischemia(P＜0.05).There was a good linear correlationship between the peak systolic CS and RD of 17 segments(except the middle segment of LV lateral wall after ischemia)and each global short-axis level before and after ischemia(r=0.662-0.995,P＜0.05,P＜0.01 or P＜0.001),The peak systolic RS of six segments and each global short-axis level(except the apex level at baseline)was correlated with RD(r=0.580-0.916,P＜0.05,P＜0.01 or P＜0.001);There was not statistical correlationship between global RDs and SV as well as LVEF.Conclusions Subendocardial circumferential strain and radial displacement may sensitively reflect the changes of regional and global myocardial systolic function induced by acute myocardial ischemia.The significant correlationship between subendocardial circumferential systolic strain and radial displacement might indicate that circumferential deformation of myocardium result in the changes of the radial displacement mainly.

Objective To investigate the value of the Changsha version of the Montreal Cognitive Assessment Scale (MoCA) in the assessment of vascular cognitive impairment after cerebral infarction .Methods 112 cases of clinically diagnosed cerebral infarc-tion were selected and divided into the normal cognition (NC) group and vascular cognitive impairment(VCI) group .The Changsha version of MoCA and the mini-mental state examination(MMSE) were adopted to detect the cognitive function ,the correlation of two scales was analyzed and the cutoff values of the Changsha version of MoCA were preliminarily studied .Results The total scores of the Changsha version of MoCA and MMSE in the VCI group were 15 .12 ± 4 .60 and 20 .44 ± 3 .22 respectively ,which were lower than 22 .75 ± 1 .79 and 25 .21 ± 1 .74 in the NC group ,the difference had statistical significance (P< 0 .05);the total scores of the Changsha version of MoCA was positively correlated with the total scores of MMSE (r=0 .84 ,P<0 .01);the best cut-off value of the Changsha version of MoCA was 20/21 ,the sensitivity and specificity were 92% and 95% respectively .Conclusion The Changsha version of MoCA can screen VCI well and has a high screening value ,and its optimal cutoff value is 20/21 .

ObjectiveTo evaluate the myocardium damage of myocardial contrast echocardiography (MCE) and the impact on regional left ventricular mechanics by imaging and pathology techniques.Methods Eleven open-chest animal models of Beagle were employed to collect the short-axis views of mitral annular,papillary muscle and apical level of three complete cardiac cycles using gray-scale imaging at the baseline and blank irradiation 5 min later(transmitting frequency 1.7/3.4 M Hz,mechanical index 1.0).After that,5 ml of SonoVue was gotten a shot by intravenous bolus injection,the heart was exposed by ultrasonic wave for 5 min continuously,and then the same images collected were at the point-in-time irradiation immediately,20 min,40 min and 60 min later.The short-axis circumferential strain and strain rate,radial strain and strain rate were measured and calculated by EchoPAC multi-parameter workstation,meanwhile including conventional of cardiac function.All the dogs were killed after the experiments and the myocardium was harvested for HE staining and observed with transmission electron microscope for the tissue microstructure.Results①Conventional parameters of cardiac function:there was no significant difference before and after MCE in the heart rate,blood pressure,ejection fraction,left ventricular end-systolic volume and end-diastolic volume,stroke volume,cardiac output,mitral flow spectrum prior to the E/A,tissue Doppler mitral annular e/a and E/e ( P ＞0.05).During the whole process of experiment,the dogs’ vital signs were stable.②Compared the segmental circumferential strain and strain rate,radial strain and strain rate between baseline and each treatment groups,these parameters had a trend of increase in most segments,but the difference was not statistically significant in most segments (P ＞0.05).③HE staining at the light microscope demonstrated a small amount of myocardial cell infiltration of inflammatory cells near the outer membrane (21.2％),and very few part of the muscle fibers dissolved and fractured (6.1％).④The section of transmission electron microscope showed all the structures were normal except that a small amount of endothelial cells were mild swelling,some red blood cells were leaked,some myofilaments were regional dissolved,the relevance ratio were 28.6 ％,42.9 ％ and 21.4 ％ respectively,and the abnormal area was less than 10％ of the entire field of vision.ConclusionsMCE has no significant impact for the global function of heart and the regional mechanical state,and furthermore there is no serious pathological damage on the myocardium.

Objective To evaluate the mechanical characteristics of systolic left ventricular(LV) transmural torsion in different LV electro-mechanical patterns using speckle tracking imaging. Methods Five open-chest canine models were employed for the acquirement of the basal, apical short-axis and four-chamber views of LV during baseline(BASE) and right atrial appendage(RAA), right ventricular apical (RVA), left ventricular lateral wall (LVL) and left ventrieular apical (LVA) pacing. Subendocardial (subend),subepicardial(subepi) and bulk rotation angle(RA) and segmental angle excursion(AE) at basal and apical level were analyzed using a dedicated workstation. LV torsion at different layers and bulk and global LV ejection fraction (EF) were calculated. Results ① There were no significant difference of transmural torsion and RA at basal and apical level between BASE and RAA pacing (P>0.05);② LV torsion of subend, subepi and bulk during RVA pacing were lower than those during RAA pacing(P0.05);LV torsion of subend and bulk during LVA pacing were lower than those during RAA pacing(P0.05);LV RA of subend,subepi and bulk at basal level during RVA and LVA pacing were lower than those during RAA pacing (P<0.05); ③ For normal electro-mechanical pattern, LV torsion of subend were significant higher than that of subepi(P<0.05), there only were a higher tendency for all pacing models (P>0.05); ④AE of segments near the pacing site decreased during different ventricle paeings (P<0.05); ⑤At BASE and during RAA pacing, LV bulk and subepi torsion were positively correlated to EF; RA of subend,subepi and bulk at basal level were positively correlated to EF. Conclusions LV transmual torsion are significantly depressed during RVA and LVA pacing. There is a spatial co-relationship between LV EF and torsion and rotation of bulk and subepi at basal level in normal LV electro-mechanical patterns.

Objeetive To evaluate the changes of left ventricular(LV) global and segmental volume, LV outlet pressure and their co-relationship, and to access LV global and segmental systolic function and mechanical asynchrony in different LV electro-mechanical patterns using full volume three-dimensional echocardiography(3DE). Methods Nineteen open-chest canine models were employed for the acquirement of LV full volume dynamic 3DE imaging during right atrial appendage (RAA), right ventricular apical (RVA), LV lateral wall(LVL) and LV apical(LVA). LV outlet end-systolic pressure(ESP) was recorded simultaneously. End-systolic volume (ESV), end-diastolic volume (EDV), global and segmental ejection fraction(EF) and systolic dyssynchrony index(SDI) of LV were measured and calculated using a dedicated workstation. The average ascending rate of LV pressure during systole(+ dp/dt) and the average descending systolic pressure(ESP), + dp/dt and - dp/dt during RVA pacing were lower than those during RAA pacing (P <0.05). SDI during RVA pacing was higher than that during RAA pacing(P<0.05). ESP, + dp/dtand - dp/dt during LVL and LVA pacing were lower than those during RAA pacing (P <0.05). There and LVA pacing was higher than that during RVA pacing (P <0.05),SD1 during LVL pacing was lower than that during RVA pacing (P <0.05), there was no significant difference of SDI between RVA and LVA and LVL pacing. Segmental EF of septum and apex during LVI. pacing were higher than those during LVA pacing (P <0.05). @Segmental EF of anterior and post septum and all apical segments (except lateral wall) during RVA pacing were lower than those during RAA pacing (P <0.05). Segmental EF of lateral and anterior wall during I.VI. pacing were lower than those during RAA pacing (P <0.05). Segmental EF of anterior wall and anterior septum during LVA pacing were lower than those during RAA parameters. Conclusions The global and minority segmental systolic function of LV during RAA pacing could be reduced compared with normal sinus rhythm. All the ventricular pacing worsen LV systolic and diastolic function compared with RAA pacing. LV systolic function during LVL pacing was superior to RVA pacing. During ventricular pacing,the systolic function at nearby segments of the pacing site was depressed.

Objective To explore the bioeffects of canine myocardium under microbubble destruction via diversity of ultrasonic intension, in order to optimize ultrasonic intension for experiments. Methods Nine mongrel dogs were randomly divided into 3 groups. Ultrasound (1 MHz) in diversity of different intension (0.5 W/cm~2, 1.0 W/cm~2, 2.0 W/cm~2) was applied to expose canine myocardium after intravenous injection microbubbles of 2.0 ml. All the dogs were killed after being exposed for 5 min. The myocardium was harvested for HE staining and observed with transmission electron microscope for the tissue microstructures. Results The myocardium of hyperemia, disfiguration and necrosis wer observed in all groups. Myocardial edema but not hemorrhage appeared with 0.5 W/cm~2 , mild myocardial hemorrhage and slight inflammatory cell infiltration happened with 1.0 W/cm~2, whereas obvious hemorrhage and certain degree of inflammatory cell infiltration occurred with intension of 2.0 W/cm~2. With the augmentation of ultrasonic intension, myocardium trend to aggravate. Conclusion Ultrasound of diversity intension can induce different bioeffects of canine myocardium. Ultrasound mediated microbubble destruction with the intensity of 1.0-2.0 W/cm~2 can provoke a certain degree of inflammatory reaction with mild myocardial damage.