What is an ileal conduit?

What is an Ileal Conduit?

An ileal conduit is a urinary diversion procedure where a segment of ileum (small intestine) is surgically isolated and used to create a passageway (conduit) that connects the ureters to the abdominal wall, requiring an external collection appliance for urine drainage. 1

Surgical Technique

The procedure involves isolating a segment of ileum while preserving its blood supply, then:

• The ureters are implanted into one end of the isolated ileal segment 1
• The other end is brought through the abdominal wall to create a stoma (opening on the skin) 2, 1
• The remaining bowel is reconnected to restore intestinal continuity 3
• The conduit is typically placed on the right abdominal wall, though left-sided placement is possible when anatomically necessary 4

Modern modifications include leaving the conduit in its natural isoperistaltic anterior position and performing anterior ureteral anastomoses, which reduces complication rates. 3

Primary Indications

The ileal conduit is the gold standard and most common urinary diversion performed after radical cystectomy for bladder cancer. 1, 5

It is particularly recommended for:

• Elderly patients, who benefit from the fastest operative time and lowest complication rates 1, 5
• Patients with significant comorbidities 1
• Patients with limited manual dexterity who cannot perform self-catheterization required for continent diversions 1
• Patients with poor renal function, as it causes the least decline in glomerular filtration rate compared to other diversions 5

Key Clinical Characteristics

Patients with an ileal conduit have no voluntary control over urination and must wear an external collection appliance (ostomy bag) continuously. 1

Important features include:

• The stoma requires specialized care and management by the patient 6
• Preoperative stoma site marking by an enterostomal therapist is essential to optimize placement and reduce complications 1
• Patient education about appliance management and stoma care is mandatory before surgery 1

Complications and Long-Term Outcomes

While the ileal conduit has the lowest reoperation rates compared to continent diversions 5, long-term surveillance is critical:

In long-term survivors (>15 years), up to 94% develop conduit-related complications, with 50% showing upper urinary tract changes. 7

Common complications include:

• Renal function deterioration and upper tract morphological changes (27% of patients) 7
• Stoma complications (24% of patients) 7, 6
• Ureteroileal anastomotic strictures (5-14% of patients) 3, 7
• Recurrent urinary tract infections and pyelonephritis (23% of patients) 7
• Urolithiasis (9-38% depending on follow-up duration) 7
• Peristomal skin complications, especially with inadequate stoma care 6

Critical Distinctions from Other Diversions

The ileal conduit differs fundamentally from ureterosigmoidostomy, where ureters are implanted directly into the sigmoid colon. 1

Key differences:

• Ureterosigmoidostomy allows continence but carries a 24% risk of adenocarcinoma at 20 years, requiring annual flexible sigmoidoscopy starting 10 years post-surgery 2, 1
• The ileal conduit isolates urine from the fecal stream, dramatically reducing cancer risk 2
• Unlike continent catheterizable diversions or neobladders, the ileal conduit requires no self-catheterization 2, 1

Quality of Life Considerations

Studies measuring health-related quality of life report excellent patient acceptability, especially in elderly populations, with many patients experiencing improved quality of life after the procedure. 5