Objective To find the clinical and histopathological predictive factors for lateral lymph node ( LN ) metastasis in thyroid papillary microcarcinoma( PTMC ).Methods From January 2007 to December 2010,141 patients with PTMC underwent central and lateral LN dissections were enrolled in the study.The data from the cases were analyzed retrospectively to determine the predictive factors for lateral LN metastasis.Results Among the aforementioned cases,37 cases ( 26.2％ ) were PTMC with the presence of multifocality,24 ( 16.9％ ) Hashimoto thyroiditis,84 ( 59.6％ ) central LN metastasis,56 ( 39.7％ ) lateral LN metastasis.Multifocality,central LN metastasis,underlying Hashimoto thyroiditis,and upper pole location were significantly related to lateral LN metastasis in univariate analysis( P＜0.05 ).These four factors were also found to be independent predictive factors for lateral LN metastasis in multivariate analysis( P＜0.05 ).9(6.4％ ) of there patients were found to show skip metastasis in which there was lateral LN metastasis but no central LN metastasis.The upper pole location was statistically significantly associated with skip metastasis.Conclusions Patients with multifocality,central LN metastasis,underlying Hashimoto thyroiditis,and upper pole location should be paid more attention to the status of lateral LN.Skip metastasis occurs in a minority of patients with PTMC.Even if there is no central LN metastasis,patients with upper pole lesion should be searched carefully for the lateral cervical LN metastasis.

Objective:To explore the application value of three-dimensional visualization technique based on CT data in the analysis of renal vascular anatomical variation.Methods:The clinical data of 210 patients with renal tumors, adrenal tumors and renal cysts who underwent renal enhanced CT from October 2020 to June 2021 were retrospectively analyzed. Among the patients, there were 114 males and 96 females with an average age of (56.5±13.2) years. The CT data were reconstructed by 3D slicer software. According to the three-dimensional visualization model, the renal vascular anatomy was analyzed from the perspective of whether it needs to be treated during laparoscopic radical nephrectomy and laparoscopic partial nephrectomy. The variation of renal artery can be divided into multiple renal arteries, premature branches of renal artery and the mixed type with the above two variations. Renal vein variation can be divided into multiple renal veins, late confluence of renal veins and mixed type with the above two variations.Results:Among the 210 patients in this study, there were no statistically significant differences in anatomical variations of renal arteries and veins between males and females ( P=0.914 and P=0.121). Among 420 kidneys, renal artery variation (174/420, 41.4%) was more common than renal vein variation (121/420, 28.8%) ( P<0.01). 32 (7.6%) right kidneys and 38 (9.0%) left kidneys have multiple renal arteries ( P=0.432). Eighty-nine cases (42.4%) had premature branches in the right renal artery, while 37 cases (17.6%) in the left kidney ( P<0.01). 24 kidneys (5.7%) showed mixed renal artery variation. 53 (12.6%) right kidneys and 3 (0.7%) left kidneys had multiple renal veins ( P<0.01). Late confluence of renal veins was found in 41 right kidneys (9.8%) and 33 left kidneys (7.9%), respectively ( P=0.306). 8 (1.9%) mixed renal vein variants were all right kidneys.. From the perspective of laparoscopic renal surgery, there were 71 cases (33.8%) of the left kidney to deal with ≥ 2 renal arteries, as well as 103 cases (49.1%) of the right kidney ( P<0.01). There were 44 cases (21.0%) of the left kidney to deal with ≥ 2 renal veins, as well as 78 cases (37.1%) of the right kidney ( P<0.01). Conclusions:The three-dimensional visualization technique based on renal CT data is helpful to accurately evaluate the renal vascular anatomy before operation. Right renal vascular variants are more common.