Contact Dissolution Therapy for Gallstones: What You Need to Know
What is contact dissolution therapy?
Contact dissolution therapy is a non‑surgical, experimental procedure that involves injecting a solvent directly into the gallbladder to dissolve cholesterol gallstones. The most commonly used solvent is methyl tert‑butyl ether (MTBE), a potent organic solvent that rapidly dissolves cholesterol stones. The solvent is delivered through a percutaneous (through the skin) catheter placed into the gallbladder under radiological guidance. The procedure was developed in the 1980s and 1990s as an alternative to cholecystectomy for patients unfit for surgery.
How MTBE dissolves gallstones
Methyl tert‑butyl ether (MTBE) is a colourless, volatile liquid that is an excellent solvent for cholesterol. When infused directly into the gallbladder, it rapidly dissolves cholesterol stones by breaking down the cholesterol matrix. Unlike oral UDCA (which takes months), MTBE acts within hours. The procedure requires multiple cycles of infusion and aspiration of the solvent to dissolve the stone and remove the dissolved cholesterol.
MTBE does not dissolve pigment stones or calcified stones. It is effective only for pure cholesterol stones.
Who is a candidate? (Very few)
Eligibility criteria are extremely narrow:
- Pure, radiolucent cholesterol stones (confirmed by CT or oral cholecystography).
- Solitary or a few small stones (<20mm total stone burden).
- Functioning gallbladder (able to empty dissolved material).
- Patient at very high risk for surgery (e.g., severe cardiac or pulmonary disease) and not a candidate for laparoscopic cholecystectomy.
- Patient refuses surgery but still wants stone removal.
Less than 5% of gallstone patients meet these criteria.
The procedure: percutaneous catheter + MTBE infusion
- Percutaneous catheter placement: Under local anaesthesia and ultrasound/CT guidance, a thin needle is inserted through the skin and liver into the gallbladder. A catheter is left in place.
- Gallbladder aspiration: Bile is aspirated to create space for the solvent.
- MTBE infusion: MTBE is infused into the gallbladder, left in contact with the stone for 5‑15 minutes, then aspirated. This cycle is repeated multiple times over several hours.
- Monitoring: The patient is closely monitored for leakage, pain, or systemic toxicity.
- Completion: Once the stone is dissolved (confirmed by repeat imaging or disappearance of stone fragments), the catheter is removed.
The entire procedure typically takes 4‑8 hours and is performed under sedation. Most patients require hospitalisation for 1‑3 days.
Success rates and stone‑free outcomes
In early clinical trials (1980s‑1990s), MTBE contact dissolution achieved:
- Complete stone dissolution in 70‑90% of patients with solitary, small (<20mm) cholesterol stones.
- Partial dissolution in another 10‑20%.
- Success rates were lower for multiple stones, stones >20mm, or non‑cholesterol stones.
However, recurrence rates after successful dissolution were 30‑50% within 3‑5 years (similar to UDCA), because the gallbladder remains and the lithogenic bile persists.
Risks and complications
Contact dissolution carries significant risks, which contributed to its abandonment:
- Catheter dislodgement or bile leak (5‑10%): Can cause peritonitis requiring surgery.
- MTBE leakage into the peritoneal cavity: Causes severe chemical peritonitis, pain, and nausea.
- Systemic absorption of MTBE: Can cause sedation, dizziness, nausea, and rarely respiratory depression.
- Acute pancreatitis (1‑2%): If MTBE refluxes into the common bile duct.
- Cholangitis or cholecystitis.
- Incomplete dissolution requiring repeat procedure.
Why contact dissolution is rarely used today
Several factors have rendered contact dissolution obsolete:
- Laparoscopic cholecystectomy is safer, faster, and definitive. It removes the gallbladder, eliminating recurrence.
- Oral UDCA is non‑invasive for the few patients who are candidates for dissolution (small cholesterol stones).
- ERCP removes common bile duct stones, and cholecystectomy addresses the source.
- The risks of MTBE (leakage, pancreatitis, systemic toxicity) are unacceptable in the modern era.
- Recurrence rates are high – patients often need surgery anyway.
Interactive FAQ – Contact dissolution therapy
Very rarely. A few research centres may offer it under experimental protocols, but it is not standard care. Laparoscopic cholecystectomy is the gold standard.
No – MTBE only dissolves cholesterol stones. Pigment stones are completely resistant.
4‑8 hours of repeated infusion and aspiration cycles, usually performed in a single session. Hospital stay of 1‑3 days.
No – the solvent cannot be safely infused into the bile duct because of the risk of pancreatitis and cholangitis. ERCP is the standard for CBD stones.
Oral dissolution (UDCA) works slowly over months, is non‑invasive, and has low toxicity. Contact dissolution is invasive, works in hours, but has significant risks and is rarely used.
Most insurers in India do not cover experimental procedures. Standard treatments (cholecystectomy, ERCP, UDCA) are covered.
MTBE leakage into the abdomen causes severe chemical peritonitis, requiring emergency surgery to irrigate the abdomen. This is a serious complication.
Yes – recurrence rate is 30‑50% within 5 years because the gallbladder is still present. Most patients eventually need cholecystectomy.
Disclaimer: Contact dissolution therapy is not a standard treatment. Laparoscopic cholecystectomy is the gold standard. Consult a gastroenterologist or surgeon at Vivekananda Hospital for appropriate management.