ORIGINAL ARTICLE Eur. J. Anat. 21 (3): 211-217 (2017) Anatomo-radiological mapping of the arrangement of ascending lumbar veins in relation to renal veins: is there a way to predict the risk of intraoperative lesions? Marcos O. Siebra-Coelho1, Rachel Carvalho2, Gilberto R. Oliveira1, Barbara Weberling2, Gustavo Carvalho-da-Silva1, Allan C. Feitosa2, Ludmilla Gomes2, Diogo P. Tavares1, André L. Saud2, João A. Pereira-Correia1,2, Valter J. Mul- ler1 1Department of Urology, Servidores do Estado Federal Hospital, 2Department of Anatomy, Faculty of Medicine, Estácio de Sá University SUMMARY sion, on the right side, respectively, and 34 (17%), 86 (42%) and 85 (41%) lumbar veins, on the left The aim of our study was to describe the critical side, respectively. The correlation between the area for iatrogenic lesions of the lumbar veins dur- size of the renal veins and the first lumbar vein- ing the intraoperative manipulation of the renal renal vein distance found a statistically significant veins and propose predictive indications for identi- difference, only on the left side (p=0.02). We de- fying those veins found in potential risk for iatro- scribe the arrangement of the lumbar veins in rela- genic lesions. Adult human cadavers were dissect- tion to the renal veins, proposing a way to predict ed and contrast enhanced images of CT and MR the existence of a "risk zone" for inadvertent, in- scans were randomly selected and analyzed. The traoperative vascular lesions. distances from the first lumbar veins to the right and left renal veins were measured, respectively. Key words: Iatrogenic disease – Kidney neo- The diameter of the renal veins and of the inferior plasms – Renal transplantation – Renal veins – vena cava was calculated. Correlation of the dis- Anatomy tances between the first lumbar veins and the cor- responding renal veins, as well as the diameter of INTRODUCTION the renal veins and the inferior vena cava was per- formed. Kidney surgeries, especially those related to kid- We obtained 205 specimens. The average dis- ney transplants (Li et al., 2011) and the resection tances between the right and left first lumbar veins of tumors that invade the inferior vena cava and their respective renal veins was 3,5cm and (Abbasi et al., 2012), can lead to various complica- 3,8cm, respectively (p<0.0001). We found 40 tions, but iatrogenic lesions of a lumbar vein, alt- (20%), 96 (46%) and 69 (34%) lumbar veins at hough uncommon, during the manipulation of the high, moderate and low risk for intraoperative le- renal vein and/or the inferior vena cava are per- haps the most dramatic ones for the urologist. As they are short and relatively small, when lesioned, Corresponding author: João A. Pereira-Correia. Rua Paulo they may retract into the adjacent adipose tissue, Barreto 28/701, Botafogo, Rio de Janeiro, RJ, Brazil 22280- 010. Phone: 55 21 9 64352027; Fax: 55 21 2595 4976. E-mail: [email protected] Submitted: 22 January, 2017. Accepted: 28 April, 2017. 211 Lumbar veins in relation to renal veins making them almost impossible to repair, and thus Cadavers and radiological examinations from evolving to intense local bleeding that is difficult to patients with retroperitoneal or macroscopic perito- control (Lawindy et al., 2012). Other specialists neal changes, such as aneurisms and tumors, and who work in this pre-vertebral area, such as vascu- those with a history of any kind of abdominal sur- lar surgeons and orthopedists specializing in the gery, either on the death certificate (cadavers) or spine, can also face difficulties when they do not on the clinical docket (radiological examinations) take into consideration the anatomical arrange- were excluded. ment of the lumbar veins (Costa et al., 2005; Flou- An experienced radiologist was invited to analyze zat-Lachaniette et al., 2013; Marchi et al., 2015). the CT and MR images. These examinations According to the classic anatomy texts, lumbar measured the distances from the upper edge of veins are responsible for the drainage of the mus- the first lumbar vein, right and left, to the lower cles of the abdomen’s posterior wall and have di- edge of the right and left renal veins, respectively. rect communication with the veins of the vertebral The distance was obtained by adding up the num- venous plexus, without the presence of valves, ber of tomographic slices between the limits of the thereby allowing for the free circulation of blood vascular structures noted above. The diameter of flow in both directions (Hollinshead, 1971; Hollins- the renal veins, bilaterally, and of the inferior vena head, 1974; Williams et al., 1989a, b). Although cava were calculated in the same way. some studies have demonstrated that these veins The cadavers were dissected through a xy- are tributaries from the posterior area of the inferi- phopubic median incision, in the subcostal and or vena cava and, eventually, of the left renal vein, bilateral inguinal section. Next, the abdominal wall the exact arrangement of these veins -especially in was pulled back, with visualization and lateral re- relation to the renal vein- has not been described moval of the abdominal organs to allow for visuali- in a precise way (Anson, 1948; Anson and Kurth, zation of the inferior vena cava. Once identified, a 1955; Davis, 1958; Monkhouse and Khalique, dissection of the renal and lumbar veins was con- 1986). These findings are generally based on dis- ducted. Anatomical specimens dissected were sections of cadavers and radiological examinations photographed using a high-resolution digital cam- involving a small number of specimens. era. The Image Pro PlusÔ software, version 4.5, Our study carefully analyzed the critical area for from Media CyberneticsÔ (Bethesda, MD, USA) iatrogenic lesions of the lumbar veins during the was used for the analysis of the distance between intraoperative manipulation of the renal veins, bas- the upper edge of the right first lumbar vein and ing ourselves on the distance from the lumbar the lower edge of the right renal vein, as well as veins to the renal veins through cadaver dissec- the distance between the upper edge of the left tions and imaging examinations. As a conse- first lumbar vein and the lower edge of the left re- quence, we propose predictive indications for iden- nal vein (Fig. 1), and also the diameter of the renal tifying those veins found in the potential risk area veins and the inferior vena cava. Each measure- for iatrogenic lesions. ment was carried out 3 times and the average among these measures was adopted by us. MATERIALS AND METHODS Next, a correlation of the distances between the first lumbar veins and the corresponding renal Adult human cadavers preserved in a 5% formal- veins was obtained, as well as the diameter of the dehyde solution and contrast enhanced images of renal veins and the inferior vena cava. CT and MR scans were selected. The cadavers The statistical analysis was performed using a were randomly obtained from the anatomy labora- commercially available data analysis program, tory of the Faculty of Medicine at the Estácio de Sá GraphPad PrismÔ, version 5 (La Jolla, CA, USA), University (Rio de Janeiro, Brazil) after study ap- applying the Kolmogorv-Smirnov´s test for the proval from the institutional Research and Ethics analysis of normality. For data with a Gaussian Committee. Epidemiological data for each cadaver distribution, a comparative inter-group evaluation from the respective death certificates were ob- using Student’s t-test was used. For data with a tained. non-Gaussian distribution, the Mann Whitney test The imaging examinations were obtained via a was used, adopting the standard significance val- random, computerized selection using the archive ue of p < 0.05. of the Radiology Department of the Servidores do Estado Federal Hospital (Rio de Janeiro, Brazil) of RESULTS examinations performed from January to July 2015. The images from computed tomography We analyzed 205 specimens, 15 from cadavers (CT) and magnetic resonance (MR) scans were and 190 from imaging examinations, divided into analyzed by OsiriX MD™ (Pixmeo, Geneva- 120 computed tomography images and 70 mag- Switzerland) workstation performing with 1.25 colli- netic resonance images of the abdomen. In terms mation/1mm reconstruction, and 1mm width, in the of gender, 90 examinations and 5 cadavers from arterial and venous phases with a fixed scan delay women and 100 examinations and 10 cadavers of 30 and 70 seconds. from men were obtained. 212 M.O. Siebra-Coelho. et al. Fig 1. Digital picture of one cadaver with the inferior vena cava exposed. We measured the distance between the upper edge of the right first lumbar vein (blue pin) and the lower edge of the right renal vein (black pin), as well as the distance between the upper edge of the left first lumbar vein (red pin) and the lower edge of the left renal vein (green pin). 213 Lumbar veins in relation to renal veins Table 1 shows the distances between the right ones most exposed to iatrogenic lesion during sur- and left first lumbar veins and their respective re- gical manipulation of the kidneys and the inferior nal veins. In table 2, the distances are divided into vena cava, in order to develop a way to predict the groups, stratified by the risk of intraoperative iatro- veins at greatest risk. genic lesion. The correlation between the size of the renal Descriptive anatomy of the lumbar veins and veins and the first lumbar vein-renal vein distance their variations found a statistically significant difference, as table General surgery, surgical oncology, liver trans- 3 shows (p=0.02). There was no statistically signifi- plantation and urology texts (Woodeburne and cant correlation between the distance from the Burkel, 1988; Standing, 2005; Gaujoux et al., right first lumbar vein to the ipsilateral renal vein 2006) describe lumbar veins, four in number on and the diameter of the right renal (p=0.054).