What anatomical structures are encountered during a laparoscopic adrenalectomy?

Anatomical Structures Encountered During Laparoscopic Adrenalectomy

During laparoscopic adrenalectomy, you will encounter the adrenal gland itself, the adrenal vein (the most critical structure requiring early identification), surrounding perinephric fat within Gerota's fascia, the upper pole of the kidney, and adjacent structures including the diaphragm, psoas muscle, transversus abdomininis muscle, liver (right side), spleen (left side), pancreatic tail (left side), inferior vena cava (right side), and potentially the pleura. 1, 2, 3

Approach-Specific Anatomical Considerations

Transperitoneal Approach (Most Common)

The lateral transperitoneal approach provides the largest operative field with familiar landmarks from open surgery, making it ideal for surgeons in their learning curve. 2, 4

Key structures by side:

Right adrenalectomy: 2, 3

• Liver - requires mobilization and retraction to expose the right adrenal gland
• Inferior vena cava - lies medial to the right adrenal gland; the right adrenal vein drains directly into it (typically short and requires careful dissection)
• Right kidney upper pole - lies inferior to the adrenal gland
• Hepatorenal ligament - must be divided for exposure
• Diaphragm - forms the superior boundary

Left adrenalectomy: 2, 3, 4

• Spleen - requires mobilization by dividing the splenorenal and splenocolic ligaments
• Pancreatic tail - lies anterior and inferior to the left adrenal gland; injury risk during dissection
• Left renal vein - the left adrenal vein drains into it (longer than right side, easier to control)
• Left kidney upper pole - lies inferior to the adrenal gland
• Diaphragm - forms the superior boundary
• Stomach and colon - may require retraction for exposure

Retroperitoneal Approach

The posterior retroperitoneoscopic approach avoids entering the peritoneal cavity and provides direct access to the adrenal gland, though the working space is more restricted. 1, 5

Key structures encountered: 1, 5

• Gerota's fascia - the dissection plane stays just inside this fascia
• Perinephric fat - dissected en bloc with the adrenal gland and kidney upper pole
• Psoas muscle - forms the medial boundary
• Transversus abdominis muscle - forms the lateral boundary
• Diaphragm - forms the superior boundary
• Upper pole of kidney - exposed after dividing perinephric fat between kidney and adrenal gland

Critical Vascular Anatomy

The adrenal vein is the single most important structure to identify and control early in the procedure. 2, 4

• Right adrenal vein: Short (often <5mm), drains directly into the posterolateral aspect of the inferior vena cava; injury can cause life-threatening hemorrhage 3
• Left adrenal vein: Longer, drains into the superior aspect of the left renal vein; generally easier to control 3
• Adrenal arteries: Multiple small vessels from the inferior phrenic artery, aorta, and renal artery; usually controlled with energy devices 2

Organs at Risk for Injury

Common intraoperative complications involve injury to adjacent structures: 3

• Vascular injuries - most serious complication; inferior vena cava, renal vessels, and adrenal veins are at highest risk
• Liver injury (right side) - from retraction or direct trauma during dissection
• Splenic injury (left side) - from mobilization or retraction
• Pancreatic tail injury (left side) - from dissection along the inferior border of the left adrenal gland
• Pleural tears - the diaphragm lies immediately superior to both adrenal glands; CO2 can enter the pleural space
• Bowel injury - from trocar placement or adhesiolysis in patients with prior abdominal surgery

Technical Dissection Sequence

The recommended dissection technique involves en bloc mobilization rather than direct adrenal gland identification at the start: 1

1. Dissect the perinephric fat (including upper kidney pole and adrenal gland) from surrounding muscles just inside Gerota's fascia
2. Divide the perinephric fat between the adrenal gland and kidney to expose the upper pole of the kidney
3. Continue dissection along the renal surface
4. Identify and control the adrenal vein early in the procedure
5. Mobilize the inferior aspect of the adrenal gland from the kidney before dividing other attachments 5

Common Pitfalls to Avoid

• Never directly identify the adrenal gland at the start of the operation - this increases risk of capsular violation and bleeding; instead, perform en bloc dissection within Gerota's fascia 1
• Always identify and control the adrenal vein early - inadvertent injury to this structure, especially on the right side, can cause catastrophic hemorrhage requiring conversion to open surgery 3, 4
• Be aware of pleural proximity - the diaphragm is immediately superior to both adrenal glands, and pleural tears occur in a small percentage of cases; recognize this intraoperatively to prevent tension pneumothorax 3
• Exercise caution with the pancreatic tail on the left - it lies along the inferior border of the left adrenal gland and can be injured during dissection, leading to postoperative pancreatitis or fistula 3