Henley's Loop (Isoperistaltic / Reversed Jejunal Loop Interposition)

What it is

Key distinction: Isoperistaltic vs. Reversed (Anti-peristaltic)

• Schwartz's Surgery explicitly states: "The reversed intestinal segment is rarely used today - and rightly so. This operation interposes a 10-cm reversed segment of intestine between the stomach and the proximal small bowel. This slows gastric emptying, but often leads to obstruction, requiring reoperation."
• When people say "Henley's loop" in modern surgical texts, they are almost always referring to the isoperistaltic jejunal interposition (not the reversed one).

Indications

1. Bile reflux gastritis after distal gastrectomy (the primary modern indication)

• Patients develop nausea, bilious vomiting, and epigastric pain with quantitative evidence of excess enterogastric bile reflux
• Usually occurs months to years after the index operation (Billroth II, gastrojejunostomy)

1. Historically also described for dumping syndrome - but isoperistaltic interposition (Henley loop) has not been successful in ameliorating severe dumping over the long term
2. Post-esophagectomy reconstruction - a modified Merendino procedure uses a jejunal loop interposed between the esophagus and stomach after resection of the distal esophagus/GEJ

Surgical Technique (Henley Loop for Bile Reflux)

1. A 40-cm segment of proximal jejunum is isolated, preserving its mesentery and blood supply
2. It is placed isoperistaltically (normal direction) between the gastric remnant and the duodenum - effectively converting a Billroth II reconstruction back toward Billroth I physiology but with a jejunal interposition
3. This restores duodenal food passage and prevents bile from refluxing into the stomach

Why it Works (Rationale)

• Restores the physiologic flow of food into the duodenum
• Allows more physiologic release of duodenal secretions and bile
• Increases gastric retention time (the longer the jejunal segment, the slower the gastric emptying)
• The average emptying time in Henley's original series was ~2 hours

Surgical Options for Bile Reflux Gastritis (Comparison)

1. Roux-en-Y gastrojejunostomy (Roux limb ≥45 cm, preferably 60 cm) - most commonly used
2. Henley loop - 40-cm isoperistaltic jejunal interposition between gastric remnant and duodenum
3. Billroth II + Braun enteroenterostomy - diverts bile away from stomach
4. Total gastrectomy + Roux esophagojejunostomy - for severe cases

Current Status

• The reversed (anti-peristaltic) jejunal segment for dumping/postvagotomy diarrhea is largely abandoned due to obstruction risk
• The isoperistaltic Henley loop for bile reflux is still described but competes with the simpler Roux-en-Y, which is generally preferred
• Sabiston's Surgery notes the anti-peristaltic loop for postvagotomy diarrhea is "not typically used today"