A digital anatomical study of the corona mortis in females

The anatomical variability of obturator vessels: Systematic review of literature

OBJECTIVE

To systematically assess available information about all variations of obturator vessels and to present the most surgically relevant types, their prevalence and calibre in order to provide a comprehensive overview for both anatomists and clinicians.

MATERIALS AND METHODS

A total of 2689 studies were found via searching the online databases. After applying exclusion criteria 44 studies were assessed. The cadaveric studies, CT angiographies, and clinical studies were included. Number of hemipelves, prevalence of each variation and calibre of identified vessels were studied. Each variation was classified as aberrant obturator artery/vein, aberrant accessory obturator artery/vein or anastomosis.

RESULTS

In included studies the average incidence of the variant obturator artery was 26% with the aberrant obturator artery being the most frequent type (with the mean calibre 2.10 mm, SD = 0.35 mm), while the overall incidence of the variant obturator vein was 55%. Presented venous structures had the mean calibre of 2.98 mm (SD = 0.56 mm).

CONCLUSIONS

According to reviewed studies, variant obturator vessels are present in a great number of patients. Due to their possible calibre larger than 3 mm they represent a structure of high clinical importance. It is important to unify the terminology and to stress out the significance to all clinicians.

Three-Dimensional in Vivo Anatomical Study of Female Iliac Vein Variations

OBJECTIVE

To investigate female iliac vein variations by using the computed tomography angiography (CTA) three-dimensional (3 D) reconstruction technique.

METHODS

We retrospectively studied 1623 patients undergoing abdominal and pelvic CTA scanning for gynecological diseases from December 2009 to December 2018. Accurate digital 3 D models of the iliac vein were constructed using Mimics 19.0 software and used to study the morphology and variations. Variations in the common iliac vein (CIV), external iliac vein (EIV) and internal iliac vein (IIV) were classified as type I, abnormal number of veins; type II, abnormal communicating branches; or type III, other variations.

RESULTS

The overall variation rates of the iliac vein and CIV were 51.57% (837/1623) and 20.33% (330/1623), respectively. The main type of CIV variation was type II. The main type I CIV variation was the absence of the CIV (98.15%), which mostly occurred on the right side (64.81%, 35/54). Type II CIV variation was the most common, with abnormal communicating branches between the left CIV and right IIV (81.78%, 211/258). The overall variation rates of the EIV and IIV were 36.66% (595/1623) and 49.60% (805/1623), respectively, mainly on the right side. The main type of variation was type I. Among them, the division of the IIV into two branches plus convergence with the ipsilateral EIV was the most common (22.98%, 373/1623).

CONCLUSION

In this study, approximately half of the patients had iliac vein variations. The preoperative identification of iliac vein variation may reduce vascular injury in pelvic surgery.

Corona Mortis: A Systematic Review of Literature

Our systematic review evaluates surgically relevant information about corona mortis (CM), such as anatomical structure, size, laterality, incidence, and anthropometric correlations. This study aimed to provide data about anastomosis in an attempt to avoid iatrogenic damage during surgery. Articles were searched online using the descriptor "Corona Mortis" in PubMed, Biblioteca Virtual em Saúde (BVS) (Literatura Latino-Americana e do Caribe em Saúde [LILACS], MEDLINE, indice bibliografico espaãol en ciencias de la salud [IBECS]), and SciELO database. The time range was set between 1995 and 2020. The articles were selected according to their titles and later the abstracts' relation to our research purpose. All the selected articles were read entirely. A manual search based of the references cited in these articles was also conducted to identify other articles or books of interest. Forty references fulfilled the criteria for this review. The mean incidence of CM was 63% (the majority venous) among 3,107 hemipelvises. The incidence of bilateral CM was lower than that of unilateral variations based on the analysis of 831 pelvises. The mean caliber of the anastomosis was 2.8 mm among 1,608 hemipelvises. There is no consensus concerning the anthropometric influences in CM. Finally, we concluded that CM is not an unusual anatomical variation and that we must not underestimate the risk of encountering the anastomosis during surgery. Anatomical knowledge of CM is, therefore, essential in preventing accidents for surgeons who approach the inguinal and retropubic regions.

"Crown of Death"; Corona Mortis, a Common Vascular Variant in Pelvis: Identification at Routine 64-Slice CT-Angiography

Objective:

To establish the incidence of arterial corona mortis variant in angiographic studies being performed using a 64 slice CT scan machine in a series of patients.

Methods:

This was a prospective cross-sectional study including 100 consecutive patients undergoing routine clinically indicated, standard protocol, CT-angiography for the abdominal aorta and/or lower limbs using a 64 slice CT scanner. Patients having severe arterial insufficiency (Grade 4 stenosis on CT angiography), pelvic infections and tumours, patients with past pelvic trauma and those who had previous pelvic surgery were excluded from the study. In total 200 hemi-pelvises were evaluated for the presence or absence of corona morti.

Results:

Overall, we included 100 patients in this series including 67 men and 33 women with mean age of 40.1±2.3 (ranging from 22-74) years. The arterial variant was identified on thin, 0.625-mm-thick images in 24 out of 100 patients studied (unilateral in 20 patients and bilateral in 4 patients; 28 out of 200 hemipelvises evaluated, having an incidence of 14%). We found that the distance of corona mortis artery from the symphysis was significantly greater for women compared to men, both on right (p=0.034) and left sides (p=0.046).

Conclusion:

Corona mortis may be prospectively identified at contrast-enhanced multidetector CT especially in pelvic trauma patients and help guide subsequent endovascular embolization or surgical interventions.

Digital anatomic study of the ureter relative to bifurcation of the common iliac artery in females

INTRODUCTION

Laparoscopic salpingo-oophorectomy and pelvic lymphadenectomy place the ureter at risk. Although traditional anatomic studies indicate that ureters generally cross over the common iliac artery in the pelvic inlet, the view is often different during surgery. Hence, digital three-dimensional models have been utilized to solve this conundrum. Our study aimed to evaluate the anatomic relation between the iliac artery and the ureter in the pelvic inlet.

MATERIAL AND METHODS

A medical image processing system processed data collected from 129 female patients, and digital 3D models of the iliac artery and ureter were used to study their anatomic relation. Left- and right-side data were compared using Pearson's χ² analysis.

RESULTS

Two different anatomic relations were found immediately posterior to the ureter: Common iliac arteries were present in 33.2% and external iliac arteries in 76.8%. The mean distances from the point at which the ureter crossed over the iliac artery until the bifurcation of the artery was 8.8 ± 12.2 mm in the left pelvis and 12.4 ± 10.8 mm in the right pelvis - different from that of the traditional anatomic study.

CONCLUSION

In the future, these models and digital anatomical data could help avoid surgical complications.

Where and what arteries are most likely injured with pelvic fractures?: The Influence of Localization, Shape, and Fracture Dislocation on the Arterial Injury During Pelvic Fractures

Blood vessels passing through pelvic region come into intimate contact with pelvic bone and can be injured by the sharp edges of the dislocated fracture fragments. The aim of the study was to evaluate the influence of localization, shape, and dislocation of individual pelvic ring bones' fractures on arterial injuries. The study group consisted of 474 patients enrolled in a 1-year prospective multicenter study. The pattern of pelvic fracture lines was characterized and recorded on a planar diagram of the subjected side of the pelvis. The diagram was subdivided into 11 designated areas. Frequency of injury at each 11 areas was recorded. The course of individual arteries in the 11 areas was also recorded in relation to each type of pelvic fractures. Out of the 474 investigated patients, the highest proportion of fractures occurred in the areas of the superior (62%) and inferior (59%) ramus of the pubis as well as in the lateral part of the sacrum (19%). These locations can be associated with injuries of the external iliac, obturator, internal iliac, and aberrant obturator arteries. The highest risk of arterial injuries was associated with vertically displaced fractures in the middle part of the superior and inferior pubic rami, along the ischial ramus, in the apex of the greater sciatic notch and in the vicinity of the ventral part of the sacroiliac joint, where the artery runs at a distance of less than 1 cm from the bone. Clin. Anat. 32:682-688, 2019. © 2019 Wiley Periodicals, Inc.

Reconstruction of three-dimensional vascular models for lymphadenectomy before surgery

Introduction: A three-dimensional (3D) model of the pelvic vessels was reconstructed before surgery to aid in the understanding of the individual anatomy and help guide lymphadenectomy performance.Material and methods: Thirty patients with early-stage cervical cancer who were scheduled for lymphadenectomy at Nanfang Hospital, Southern Medical University from January 2017 to June 2017 were included. Three-dimensional models of the pelvic vessels were obtained.Results: All 3D models of the 30 patients were reconstructed successfully and were consistent with the operative findings.The most common structural types posterior to the common iliac artery (CIA) and CIA bifurcation (CIAB) were non-vessel structures (23/30 patients) and the common iliac vein (CIV) (27/30); these were observed separately on the left pelvic vein. The confluence of common iliac vein (CCIV) (29/30) and CIV (20/30) were most commonly observed posterior to the CIA and CIAB; these were observed separately on the right pelvic vein. Venous abnormalities were identified in 15 patients. There were variants in venous confluence shown to be homolateral to the CIV (2/15) and contralateral to the CIV (2/15) and CCIV (4/15).Conclusions: Three-dimensional models of the pelvic vessels can provide information on individual anatomy features that can help guide lymphadenectomy performance.

The prevalence and morphology of the corona mortis (Crown of death): A meta-analysis with implications in abdominal wall and pelvic surgery

PURPOSE

Corona mortis is a highly variable vascular connection between the obturator and external iliac or inferior epigastric arteries or veins located behind the superior pubic ramus in the retropubic space (space of Retzius). Due to the significant variation in this collateral circulation, detailed anatomical knowledge of the corona mortis is vital to enhance the prevention of possible iatrogenic errors in hernia repair and other pubic surgical procedures. The aim of our meta-analysis was to provide comprehensive data on the prevalence, anatomical characteristics, and ethnic variations of the corona mortis vessel.

METHODS

An extensive search was conducted through the major electronic databases to identify eligible articles. Data extracted included investigative method, prevalence of the corona mortis vessels among hemi-pelvises (overall, arterial only, venous only, and combined), distance from the corona mortis to pubic symphysis, and assessment of gender, side, laterality, and ethnicity subgroups.

RESULTS

A total of 21 studies (n=2184 hemi-pelvises) were included in the meta-analysis. The overall prevalence of the corona mortis in hemi-pelvises is high (49.3%). A venous corona mortis is more prevalent than an arterial corona mortis (41.7% vs. 17.0%). The corona mortis is more common in Asia (59.3%) than in Europe (42.8%) and North America (44.3%).

CONCLUSIONS

As a corona mortis is present in an about half of all hemi-pelvises, it is important to consider the possibilities of its presence when undertaking surgical procedures and plan accordingly to avoid injuries. All surgeons operating in the retropubic region should have a thorough understanding of the anatomical characteristics and surgical implications of a corona mortis.