Overview
Definition:
Anatomical right posterior sectionectomy is a surgical procedure involving the removal of segments VI and VII of the liver, based on the branching pattern of the portal vein and hepatic artery
These segments constitute the posterior portion of the right hepatic lobe, representing approximately 10-15% of total liver volume
It is a precisely defined resection adhering to anatomical landmarks, distinct from more extended resections like a right hepatectomy.
Epidemiology:
The incidence of this specific procedure is relatively low and is primarily dictated by the prevalence of liver pathologies affecting these segments, such as solitary hepatocellular carcinomas (HCC), colorectal metastases, or benign tumors
Patient selection is critical, as these segments are less accessible and have a distinct vascular supply, making the decision for resection dependent on tumor location and resectability margins.
Clinical Significance:
This operation is crucial for achieving oncological clearance in patients with localized liver tumors within segments VI and VII, particularly when preserving a larger portion of functional liver parenchyma is desired
It represents a more conservative approach than a formal right hepatectomy, thus potentially reducing postoperative morbidity and improving functional recovery
Mastery of this technique is essential for surgical residents preparing for DNB and NEET SS examinations, as it tests detailed knowledge of liver anatomy and complex hepato-biliary dissection.
Indications
Primary Liver Tumors:
Resectable hepatocellular carcinoma (HCC) confined to segments VI and VII
Other primary liver malignancies like cholangiocarcinoma or adenoma in these specific segments.
Metastatic Disease:
Isolated metastases from colorectal, neuroendocrine, or other primaries located predominantly within segments VI and VII, with clear resection margins achievable.
Benign Lesions:
Large or symptomatic benign tumors, such as hemangiomas or focal nodular hyperplasia, in segments VI or VII that require removal for diagnosis or symptom relief.
Anatomical Considerations:
Tumors that are centrally located within the posterior section, making segmental resection technically feasible and oncologically sound, while preserving adequate future liver remnant (FLR).
Preoperative Preparation
Patient Assessment:
Comprehensive evaluation of liver function (Child-Pugh score, MELD score), cardiopulmonary status, and overall performance status
Assessment of the future liver remnant (FLR) is paramount, often requiring volumetric analysis via CT or MRI.
Imaging Studies:
Multi-detector CT angiography (MDCTA) and contrast-enhanced MRI are essential for precise tumor localization, vascular anatomy (portal veins, hepatic veins, hepatic arteries), biliary tree mapping, and evaluation of potential invasion into major vessels or adjacent structures.
Medical Optimization:
Correction of coagulopathy, nutritional support, and management of ascites or portal hypertension if present
Prophylactic antibiotics are administered.
Surgical Planning:
Detailed operative plan, including the choice of incision, type of hepatectomy (e.g., open vs
laparoscopic), intraoperative ultrasound guidance, and potential need for vascular stapling or isolation of major vessels.
Procedure Steps
Patient Positioning And Incision:
Patient is placed in the supine position
A subcostal or Mercedes-Benz incision is typically used for open surgery
laparoscopic surgery may utilize multiple small ports.
Liver Mobilization:
Mobilization of the right lobe of the liver by dividing the triangular and coronary ligaments
Careful dissection to expose the suprahepatic and infrahepatic inferior vena cava.
Intrahepatic Pedicle Approach:
Identification and isolation of the portal pedicle supplying segments VI and VII
This is achieved by dissecting along the right portal vein branch
Division of the corresponding hepatic artery and portal vein branches is performed using vascular staplers or ligatures.
Hepatic Vein Division:
Identification and ligation/division of the hepatic veins draining segments VI and VII into the inferior vena cava
The right hepatic vein might require management if it drains these segments, or smaller segmental veins.
Parenchymal Dissection:
Transection of the liver parenchyma along the planned resection plane, guided by anatomical landmarks and often using energy devices like ultrasonic dissectors or harmonic scalpels
Careful hemostasis is maintained throughout.
Completion And Drainage:
Inspection of the resection surface for active bleeding or bile leakage
Placement of surgical drains in the resection bed and abdominal cavity
Closure of the abdominal incision in layers.
Postoperative Care
Monitoring:
Close monitoring of vital signs, urine output, and hemodynamic stability
Serial assessment for signs of bleeding or biliary leak (e.g., drain output, abdominal pain, jaundice).
Pain Management:
Adequate analgesia, often using patient-controlled analgesia (PCA) or epidural anesthesia in the immediate postoperative period.
Fluid And Electrolyte Balance:
Intravenous fluid management to maintain euvolemia and electrolyte balance
Monitoring of liver function tests and coagulation parameters.
Nutritional Support:
Early enteral feeding is encouraged once bowel function returns
If unable to tolerate oral intake, parenteral nutrition may be initiated.
Complication Surveillance:
Vigilance for complications such as post-hepatectomy liver failure, biliary fistula, intra-abdominal abscess, or hemorrhage
Prompt initiation of treatment if suspected.
Complications
Early Complications:
Post-hepatectomy liver failure (PHLF), defined by the International Study Group of Liver Surgery (ISGLS) criteria
Biliary leak or fistula from the cut surface or severed ducts
Intra-abdominal bleeding or hematoma
Wound infection or dehiscence
Pneumonia and atelectasis.
Late Complications:
Biliary strictures, leading to obstructive jaundice or cholangitis
Bile duct stones
Incisional hernia
Adhesions causing bowel obstruction
Chronic pain syndromes.
Prevention Strategies:
Accurate FLR assessment and contralateral lobe hypertrophy if indicated
Meticulous surgical technique with precise vascular and biliary dissection
Careful hemostasis and bile duct management
Intraoperative ultrasound
Prompt recognition and management of complications
Optimizing patient’s nutritional status pre- and post-operatively.
Key Points
Exam Focus:
Understanding the segmental anatomy of the liver, particularly segments VI and VII
Indications for limited resections vs
major hepatectomies
Principles of parenchymal dissection and vascular control
Knowledge of perioperative management and common complications.
Clinical Pearls:
The right posterior section receives its vascular supply from branches of the right portal vein and right hepatic artery
These segments are drained by multiple small hepatic veins directly into the IVC, or sometimes via the right hepatic vein
Precise identification of these pedicles is crucial for safe resection
Always have a low threshold for intraoperative ultrasound to confirm tumor location and vascular involvement.
Common Mistakes:
Inadequate assessment of FLR, leading to post-operative liver failure
Incomplete resection of tumor due to insufficient margins
Uncontrolled bleeding from inadvertent injury to major vessels or hepatic veins
Missed biliary leak, leading to delayed complications like abscess or sepsis
Performing a major hepatectomy when a segmental resection would suffice, increasing morbidity.