Objective To investigate the pathologic bases of MRI manifestations of rabbit VX2 hepatic carcinoma.Methods 32 foci of hepatic carcinoma models in 20 rabbits VX2 were set up by implantation.Plain MR examinations in all rabbits and contrast-enhanced MR scan in 10 rabbits(15 foci) were performed 2~4 weeks after implantation.The largest transverse section specimens of all the tumors were obtained for imaging-pathology comparative study after MR scan.Results All the 32 tumors were detectable on both T1WI and T2WI.The size of the tumors ranged from 0.5 to 3.5 cm in diameter.6 foci showed homogeneous slight hyperintense on T2WI,the other 26 showed characteristic intratumoral signal intensity on T2WI,including "nodule in nodule"sign in 5 foci,"target"sign in 7 foci,and "dot and color"sign in 14 foci.The characteristic intratumoral signal showed on T2WI were pathologically testified as necrotic tumor tissue of different structures.All the 15 tumors with contrast-enhanced scan appeared annular enhancement in different degrees,slight enhancement in 6,medium enhancement in 7 and obvious enhancement in 2.The sinusoidlike vascular space between tumor cells were significantly dilated in the obvious enhancement cases,and there were many spots of necrosis in the slight enhancement tumors under microscope.Conclusion The tectology of intratumoral necrosis can be evaluated by T2WI.Enhanced degree after administration of contrast agent in the hepatic cancer in rabbit model is associated with dilating degrees of sinusoidlike vascular space and number of dotted necrosis of tumors.

OBJECTIVETo investigate the clinical efficacy of ligation of intersphincteric fistula tract (LIFT) in the treatment of simple anal fistula, including transphincteric anal fistula and insphincteric anal fistula.

METHODSClinical data of 52 patients with anal fistula receiving surgery treatment in Beijing Anorectal Hospital from January to October 2014 were analyzed retrospectively. Adoption of surgical procedure was based on rectal endoluminal ultrasound and patients' decision. Patients were divided into LIFT group and seton group. The two groups were compared in terms of operation time, blood loss, postoperative pain score, incidence of urinary retention, wound healing time, cure rate, recurrence, and the anal incontinence score.

RESULTSThere were 52 patients in the entire cohort including 28 cases of transphincteric anal fistula (14 cases of LIFT and seton placement groups) and 24 cases of intersphincteric anal fistula (12 case of LIFT and seton placement). The operation time was shorter in seton placement group in patients with two simple anal fistula [(23.9±5.0) min vs. (46.3±7.7) min, P<0.05]. LIFT postoperative pain score [(1.6±0.6) vs. (6.1±1.3)], wound healing time [(7.9±2.0) days vs. (30.0±5.1) days], postoperative hospital stay [(10.3±3.1) days vs. (20.7±7.1) days], and anal incontinence scores [(1.1±0.4) vs. (4.9±1.1)] were better than that of anal fistula seton (all P<0.05). There was no statistically significant difference in intraoperatie blood loss [(23.1±4.7) ml vs. (23.3±4.7) ml, P>0.05]. The cure rate of intersphincteric anal fistula was 83.3%(10/12) in LIFT group, and 100%(12/12) in the seton group. The cure rate of transphincteric anal fistula was 78.6% (11/14) in LIFT and 92.9%(13/14) in anal fistula seton group. There was no statistically significant difference (P>0.05).

CONCLUSIONIn the treatment of transphincteric fistula tract and intersphincteric fistula tract, LIFT procedures should be considered.

Digestive System Surgical Procedures ; Fecal Incontinence ; Humans ; Length of Stay ; Ligation ; Operative Time ; Pain, Postoperative ; Postoperative Period ; Rectal Fistula ; Recurrence ; Retrospective Studies ; Wound Healing