Anatomical Variations of the Venous Drainage from the Left Adrenal Gland: An Anatomical Study

Perioperative management of phaeochromocytoma with stress cardiomyopathy and aberrant vascular drainage

The following case discusses the surgical considerations for a patient presenting with cardiogenic shock secondary to a phaeochromocytoma crisis with stress cardiomyopathy. The patient underwent an interval laparoscopic adrenalectomy. Pneumoperitoneum insufflation was performed at lower pressures; manipulation of the adrenal tumour was minimised, and the adrenal vein was ligated early. However, as intraoperative blood pressure (BP) remained elevated and rising, further gentle dissection revealed an aberrant inferior phrenic vein draining the adrenal nodule. BP was finally reduced following ligation of the inferior phrenic vein, demonstrating the clinical significance of an unusual dual venous drainage from the adrenal nodule in this patient.

A cadaveric anatomical study of the adrenals: vascular relationship

The adrenal gland is a retroperitoneal organ with intimate relationships with neighboring organs but also with the large retroperitoneal vessels. Our aim was to study the vascular relationships of the adrenal gland with the large abdominal vessels. Our work is an anatomical dissection of 80 fresh cadaveric adrenals. The subjects didn't have a history of retroperitoneal surgery. Dissection conditions were similar to those in the living. All measurements were made in situ. On the right side, the average distance between the adrenal gland and the renal vein (DR) was 13 mm (0-20). In one case, the adrenal gland laid directly on the right renal vein (DR = 0). The average length L, over which the right adrenal gland entered behind the inferior vena cava (IVC), was 8 mm (0-12). In 4 cases, the right adrenal was lateral to the IVC and in 6 cases the length L exceeded 10 mm. On the left side, the mean distance DL, separating the adrenal gland from the left renal vein was 8 mm with extremes ranging from 0 mm to 18 mm. In eleven cases, the adrenal gland laid directly on the left renal vein. The right adrenal gland has a close relationship with the IVC and is often located behind it. This close relationship helps to explain the increased incidence of IVC lesions during surgery. The left adrenal gland has an intimate relationship with the left renal vein and often lies on top of it. This explains the risk of injury to the left renal pedicle during left adrenal surgery.

A Practical Guide for Left Adrenal Vein Sampling in Patients with Left Renal Vein Variants

BACKGROUND

The presence of left renal vein (LRV) variants can increase the complexity of adrenal vein sampling (AVS), an already technically demanding procedure. While AVS literature often focuses on the right adrenal vein, an understanding of common LRV variants, their relationship with the left adrenal vein, and principles for successful catheterization can facilitate AVS. This guide provides practical, technical tips for AVS for duplicated (Du), circumaortic (Ca), and retroaortic (Ra) LRVs.

METHODS

AVS cases were identified at a single institution (June 2009-March 2023) based on adrenophrenic trunk drainage relative to variant LRVs. Available cross-sectional imaging was reviewed to evaluate LRV anatomy pre-procedure. Twenty-seven cases (1 DuLRV, 13 CaLRVs, and 13 RaLRVs) were identified. Diagnostic AVS was confirmed by a threshold selectivity index. Literature on LRV anatomic variants was also reviewed.

RESULTS

Based on the authors' experience and literature review, the following principles can guide AVS in the setting of LRV variants. In the presence of DuLRV or CaLRV, the left adrenal vein invariably drains into a normally positioned, pre-aortic LRV limb, so AVS can proceed as expected with a Simmons as the catheter of choice. In contrast, a LAV draining into a RaLRV may require a hockey stick-like catheter, or in rare cases a microcatheter, for selecting and sampling, due to the longer RaLRV course, which usually drains into the IVC more inferiorly and can be stenotic where the aorta crosses.

CONCLUSION

Knowing the presence and understanding the anatomy of LRV variants can facilitate an efficient AVS.

A cadaveric anatomical study: anatomy and anatomical variations of left adrenal vein

PURPOSE

Control of adrenal vein is the key of adrenal surgery. Its anatomy can present variations. Our aim was to study the anatomy of the main left adrenal vein (LAV) and its anatomical variations.

METHODS

Our work is based on dissection of 40 cadavers. We studied the number of LAV and the drainage of the main adrenal vein as well as its level of termination. We measured its length, its width and the distance between its termination level and the termination level of the gonadal vein (GV).

RESULTS

The average length of the LAV was 21 mm its mean width was 5 mm. It ended in 100% of cases at the upper edge of the left renal vein after an anastomosis with the lower phrenic vein in 36 cases (90%) and without anastomosis with the lower phrenic vein in four cases (10%). The left adrenal vein ended at the upper edge of the left renal vein either at the same level as the termination of the left GV in 14 cases (35%) or within the termination of the left GV in 26 cases (65%) by an average of 8 mm. The LAV was unique central vein in 22 cases (55%) and in 12 cases (30%), a major central adrenal vein with several small veins was found.

CONCLUSIONS

The LAV is usually unique but there are variations in number. There are also variations in the level of its termination in the left renal vein as well as its anastomosis. During surgery, in case of difficulty, the left GV and the adrenal-diaphragmatic venous trunk could be used as benchmarks.

Anatomical Variations of the Left Adrenal Vein Encountered During Venous Sampling

PURPOSE

To identify anatomical variations in the left adrenal vein (LAV) and to evaluate the role of preprocedural contrast-enhanced computed tomography (CT) planning.

METHODS

The length of the left adrenal central vein (LACV), the vessel that receives blood from all tributaries of the left adrenal gland, was measured using venograms of patients who had undergone adrenal venous sampling (AVS) for the diagnosis of primary aldosteronism between October 2017 and December 2019. The anatomical variants of the LAV were described and classified. Contrast-enhanced CT was used to evaluate the detection rate of the following: (a) confluence of the left inferior phrenic vein and the LAV and (b) the last tributary flowing into the LAV.

RESULTS

In total, 311 patients (143 men, 168 women; mean age: 49.3 years ± 11.0) were enrolled. Of them, 9 (2.9%) patients had anatomical variants lacking a LACV. In patients with a LACV (n = 302), the venographic LACV length was 9.0 mm ± 3.9 (<1 mm in 9 patients). The detection rate of the confluence of the left inferior phrenic vein and LAV, as determined using contrast-enhanced CT, was high (96.2%), whereas that of the last tributary flowing into the LAV was low (0.8%). In 4 of 18 patients with short or absent LACV, the variant was visualized using contrast-enhanced CT.

CONCLUSIONS

In some patients, the LACV is absent or short, which is an anatomical variation. Understanding venographic anatomical variations can help avoid misleading results resulting from a suboptimal sampling site in AVS. For some subtypes, contrast-enhanced CT may also help in planning the AVS procedure.

A Rare Independent Left Inferior Phrenic Vein Sampling in a Left Adrenal Aldosterone-Producing Adenoma

This report presents a case of left adrenal aldosterone-producing adenoma (APA) diagnosed by segmental adrenal venous sampling in a patient with primary aldosteronism and a rare venous anomaly in which the left inferior phrenic vein (LIPV) and adrenal central vein entered the left renal vein separately. The outflow of tumor blood into the LIPV and the specimen from the LIPV that showed much higher aldosterone level than that from the adrenal central vein and tributaries were useful for proving the aldosterone hypersecretion from the APA. Sampling from the LIPV could be of diagnostic value for left APA.

Experience in identifying the variant adrenal venous anatomy during modified retroperitoneoscopic adrenalectomy

Background:

Adrenal vein plays an important role in performing laparoscopic adrenalectomy successfully. However, it often presents with a multitude of venous anatomical variants. Hence, having a thorough knowledge on the variant types is crucial to reduce operative complications. This study aims to present our experience in identifying adrenal vein variation in adrenalectomy through modified retroperitoneal approach.

Patients and Methods:

A total of 187 patients underwent modified retroperitoneoscopic adrenalectomy between July 2017 and February 2019. Perioperative data and adrenal vein variants were recorded and analysed.

Results:

Variant adrenal veins were encountered in seven patients. On the right side, two cases were drained by two adrenal veins; one case had a common trunk of adrenal vein and an accessory hepatic vein and one case had an adrenal vein joined with the opening of the right renal vein. On the left side, two cases of anatomic variations were described as follows: one vein converged with the left inferior phrenic vein and joined with the left renal vein, whereas the other vein directly joined with the left renal vein. One case had two adrenal veins that joined with the left renal vein.

Conclusions:

Accurate identification and proper handling of the anatomical variation in the drainage of adrenal vein are crucial to safe LA. It is helpful to anticipate and avoid bleeding, especially in large adrenal tumours.