Overview
Definition:
Complex perineal hernia repair post-exenteration refers to the surgical management of a hernia that develops in the perineal region following the removal of pelvic organs (exenteration)
Exenteration, a radical surgical procedure for advanced pelvic malignancies, significantly alters pelvic anatomy and can lead to loss of abdominal wall integrity, predisposing to various types of hernias, including perineal ones.
Epidemiology:
The incidence of perineal hernias post-exenteration is not precisely defined but is considered a significant complication
Factors increasing risk include the extent of resection, previous radiation therapy, obesity, and poor nutritional status
It is more commonly seen after abdominoperineal resection or pelvic exenteration for rectal, anal, or gynecological cancers.
Clinical Significance:
These hernias pose significant challenges due to the compromised tissue planes, potential for infection, and recurrence
Effective repair is crucial for restoring anatomical continuity, improving quality of life by relieving symptoms like pain and discomfort, and preventing life-threatening complications such as bowel obstruction or strangulation
It demands advanced surgical expertise and often requires multidisciplinary approaches.
Clinical Presentation
Symptoms:
A palpable bulge or swelling in the perineum, often exacerbated by straining or standing
Pain or discomfort in the perineal area
Sensation of heaviness or pressure
Symptoms of bowel obstruction if the hernia is incarcerated, such as nausea, vomiting, and abdominal distension
Post-void dribbling or difficulty with urination due to pressure on bladder or urethra
Dyspareunia in female patients.
Signs:
A reducible or irreducible bulge in the perineum
Tenderness on palpation of the perineal region
Redness or signs of inflammation if incarcerated or strangulated
Bowel sounds may be absent or hyperactive depending on obstruction
Rectal examination may reveal prolapse of bowel into the hernia sac or identify the fascial defect.
Diagnostic Criteria:
Diagnosis is primarily clinical, confirmed by imaging
Presence of a perineal bulge associated with symptoms suggestive of hernia
Imaging findings demonstrating abdominal contents protruding through a defect in the pelvic floor or perineum.
Diagnostic Approach
History Taking:
Detailed history of the prior exenteration procedure, including type of cancer, extent of resection, and any complications
Previous radiation therapy to the pelvis is a critical factor
Onset and progression of perineal bulge and associated symptoms
Bowel and bladder function changes
Nutritional status and comorbidities.
Physical Examination:
A thorough examination of the perineum, assessing the size, reducibility, and contents of the bulge
Palpation of the defect
Digital rectal examination to assess the pelvic floor integrity and identify contents
Examination of the abdominal wall for other potential hernia sites
Assess for signs of infection or strangulation.
Investigations:
Ultrasound of the perineum can identify the bulge and its contents
CT scan of the pelvis and abdomen is the imaging modality of choice, delineating the hernia sac, contents, and the size and location of the defect, as well as assessing the condition of surrounding tissues and abdominal viscera
MRI may be useful in complex cases to evaluate soft tissues and relationships
Contrast-enhanced studies can confirm bowel involvement.
Differential Diagnosis:
Other perineal masses such as abscess, hematoma, or desmoid tumors
Rectal prolapse
Pudendal nerve entrapment syndrome
Post-surgical seroma or lymphocele
Vulvar or scrotal swelling of other etiologies.
Management
Initial Management:
For asymptomatic or minimally symptomatic hernias with no signs of incarceration, conservative management may be considered initially, but surgical repair is usually indicated due to high recurrence risk and potential for complications
For incarcerated or strangulated hernias, urgent surgical intervention is mandatory to relieve obstruction and prevent tissue necrosis.
Surgical Management:
The goal is to reduce the hernia contents, repair the fascial defect, and reinforce the pelvic floor
Techniques include: Primary suture repair of fascial defects, often reinforced with synthetic or biological mesh
Use of abdominal wall flaps or musculocutaneous flaps (e.g., VRAM, gluteal flap) to provide tissue coverage and support
Robotic or laparoscopic approaches may be used for some repairs, especially for associated abdominal wall defects
Considerations include patient's physiological status, extent of defect, and available tissues.
Preoperative Preparation:
Optimizing nutritional status, controlling comorbidities (diabetes, hypertension), and smoking cessation are essential
Preoperative antibiotics are standard
Bowel preparation may be required depending on the surgical approach
Markings for flap harvest if indicated
Consultations with nutritionists, anesthesiologists, and potentially stoma nurses.
Postoperative Care:
Close monitoring for recurrence, infection, wound complications, and flap viability
Pain management
Early mobilization
Wound care and drain management
Nutritional support
Gradual return to diet
Stool softeners to prevent straining
Monitoring of bowel and bladder function
Long-term follow-up is essential.
Complications
Early Complications:
Wound infection, dehiscence, seroma, hematoma
Flap necrosis or failure
Urinary tract infections
Deep vein thrombosis and pulmonary embolism
Rectal or vaginal injury
Persistent perineal pain.
Late Complications:
Hernia recurrence is a significant concern, particularly with large defects or mesh complications
Chronic pain syndromes
Fistula formation (recto-perineal or vesico-perineal)
Chronic wound issues
Difficulty with sexual function
Bowel function abnormalities.
Prevention Strategies:
Meticulous surgical technique, including secure closure of fascial defects and adequate flap coverage
Use of appropriate mesh material (e.g., non-absorbable synthetic for tension-free repair, biological mesh for contaminated fields or thin tissues)
Preoperative optimization of patient factors
Careful handling of tissues
Adequate postoperative care and patient education.
Prognosis
Factors Affecting Prognosis:
The success of repair depends on the size and complexity of the defect, the patient's overall health, the presence of comorbidities, previous radiation exposure, and the surgical technique employed
Recurrence rates can be high in complex cases.
Outcomes:
Successful repair leads to relief of symptoms, restoration of perineal contour, and prevention of complications
However, recurrence remains a possibility
Long-term functional outcomes related to bowel and bladder control can be variable.
Follow Up:
Regular follow-up appointments are crucial to monitor for recurrence, wound healing, and functional status
This typically involves physical examinations and may include imaging at intervals of 3-6 months initially, then annually for several years
Patient education on recognizing signs of recurrence is vital.
Key Points
Exam Focus:
Understand the pathophysiology of perineal hernia post-exenteration
Recognize the high-risk factors
Differentiate surgical techniques for repair, including mesh use and flap reconstruction
Be aware of common early and late complications, with a focus on recurrence.
Clinical Pearls:
Preoperative optimization is paramount
Multidisciplinary approach involving colorectal, gynecological, and plastic surgeons is often necessary
When using mesh, consider biological options in contaminated fields or cases with thin, irradiated tissue
Flap reconstruction offers robust reinforcement and coverage
Patience and meticulous technique are key to minimizing recurrence.
Common Mistakes:
Underestimating the complexity of the defect and surrounding tissue
Inadequate fascial closure or reinforcement
Poor flap design or inset
Insufficient postoperative care and patient follow-up
Failure to consider the impact of prior radiation therapy on tissue healing.