Extracorporeal shock-wave lithotripsy and endoscopy: combined therapy for problematic bile duct stones

Determination of colonoscopy indication from administrative claims data

BACKGROUND

Colonoscopy outcomes, such as polyp detection or complication rates, may differ by procedure indication.

OBJECTIVES

To develop methods to classify colonoscopy indications from administrative data, facilitating study of colonoscopy quality and outcomes.

RESEARCH DESIGN

We linked 14,844 colonoscopy reports from the Clinical Outcomes Research Initiative, a national repository of endoscopic reports, to the corresponding Medicare Carrier and Outpatient File claims. Colonoscopy indication was determined from the procedure reports. We developed algorithms using classification and regression trees and linear discriminant analysis (LDA) to classify colonoscopy indication. Predictor variables included ICD-9CM and CPT/HCPCS codes present on the colonoscopy claim or in the 12 months prior, patient demographics, and site of colonoscopy service. Algorithms were developed on a training set of 7515 procedures, then validated using a test set of 7329 procedures.

RESULTS

Sensitivity was lowest for identifying average-risk screening colonoscopies, varying between 55% and 86% for the different algorithms, but specificity for this indication was consistently over 95%. Sensitivity for diagnostic colonoscopy varied between 77% and 89%, with specificity between 55% and 87%. Algorithms with classification and regression trees with 7 variables or LDA with 10 variables had similar overall accuracy, and generally lower accuracy than the algorithm using LDA with 30 variables.

CONCLUSIONS

Algorithms using Medicare claims data have moderate sensitivity and specificity for colonoscopy indication, and will be useful for studying colonoscopy quality in this population. Further validation may be needed before use in alternative populations.

Recent advances in endoscopic management of difficult bile duct stones

Endoscopic treatment is now recognized worldwide as the first-line treatment for bile duct stones. Endoscopic sphincterotomy combined with basket and/or balloon catheter is generally carried out for stone extraction. However, some stones are refractory to treatment under certain circumstances, necessitating additional/other therapeutic modalities. Large bile duct stones are typically treated by mechanical lithotripsy. However, if this fails, laser or electrohydraulic lithotripsy (EHL) is carried out under the guidance of conventional mother-baby cholangioscopy. More recently, direct cholangioscopy using an ultrathin gastroscope and the newly developed single-use cholangioscope system - the SpyGlass direct visualization system - are also used. In addition, extracorporeal shock wave lithotripsy has also been used for stone fragmentation. Such fragmentation techniques are effective in cases with impacted stones, including Mirizzi syndrome. Most recently, endoscopic papillary large balloon dilationhas been introduced as an easy and effective technique for treating large and multiple stones. In cases of altered anatomy, it is often difficult to reach the papilla; in such cases, a percutaneous transhepatic approach, such as EHL or laser lithotripsy under percutaneous transhepatic cholangioscopy, can be a treatment option. Moreover, enteroscopy has recently been used to reach the papilla. Furthermore, an endoscopic ultrasound-guided procedure has been attempted most recently. In elderly patients and those with very poor general condition, biliary stenting only is sometimes carried out with or without giving subsequent dissolution agents.

Efficacy of percutaneous treatment of biliary tract calculi using the holmium:YAG laser

BACKGROUND

Few Western studies have focused on percutaneous techniques using percutaneous transhepatic choledochoscopy (PTHC) and holmium:yttrium-aluminum-garnet (YAG) laser to ablate biliary calculi in patients unable or unwilling to undergo endoscopic or surgical removal of the calculi. The authors report the efficacy of the holmium:YAG laser in clearing complex biliary calculi using percutaneous access techniques.

METHODS

This study retrospectively reviewed 13 non-Asian patients with complex secondary biliary calculi treated percutaneously using holmium:YAG laser. Percutaneous access was accomplished via left, right, or bilateral hepatic ducts and upsized for passage of a 7-Fr video choledochoscope. Lithotripsy was performed under choledochoscopic vision using a holmium:YAG laser with 200- or 365-microm fibers generating 0.6 to 1.0 joules at 8 to 15 Hz. Patients underwent treatment until stone clearance was confirmed by PTHC. Downsizing and subsequent removal of percutaneous catheters completed the treatment course.

RESULTS

Seven men and six women with an average age of 69 years underwent treatment. All the patients had their biliary tract stones cleared successfully. Of the 13 patients, 3 were treated solely as outpatients. The average length of percutaneous access was 108 days. At this writing, one patient still has a catheter in place. The average number of holmium:YAG laser treatments required for stone clearance was 1.6, with no patients requiring more than 3 treatments. Of the 13 patients, 8 underwent a single holmium:YAG laser treatment to clear their calculi. Prior unsuccessful attempts at endoscopic removal of the calculi had been experienced by 7 of the 13 patients. Five patients underwent percutaneous access and subsequent stone removal as their sole therapy for biliary stones. Five patients were cleared of their calculi after percutaneous laser ablation of large stones and percutaneous basket retrieval of the remaining stone fragments. There was one complication of pain requiring admission, and no deaths.

CONCLUSIONS

The use of PTHC with holmium:YAG laser ablation is safe and efficacious, but requires prolonged biliary access and often multiple procedures to ensure clearance of all calculi.

An audit of the outcome of long-term biliary stenting in the treatment of common bile duct stones in a general hospital

BACKGROUND

This study audited the clinical outcome of a cohort of patients with choledocholithiasis treated with long-term biliary stenting in order to determine the feasibility of this practice.

METHODS

Over 2 years, 83 patients with symptomatic choledocholithiasis were treated with long-term stenting because they either refused further treatments or were medically unfit for further procedures after the initial endoscopic retrograde cholangiopancreatography (ERCP). Recurrence of clinical events, need for stent change, morbidity, and mortality were analyzed. As a secondary analysis, published data on long-term biliary stenting were reviewed.

RESULTS

ERCP and biliary stenting were successful in all cases with no complications. The mean follow-up was 19 months (1-103 months). The median number of ERCPs performed was 1 (1-4). The mean duration of stent patency was 12.4 months (1-54.8 months). A total of 28 clinical events (cholangitis, 71%) occurred in 24 patients during follow-up, for a late complication rate of 33.7%. ERCP was repeated and the stents changed on 15 occasions in 11 asymptomatic patients with abnormal liver function tests detected on routine follow-up. No biliary-related mortality occurred. Review of published data revealed a mean late complication rate of 22.4% (0%-64%), a biliary-related mortality rate of 3.5% (0%-21.1%), and a nonbiliary-related mortality rate of 20.8% (0%-60.3%).

CONCLUSIONS

Long-term biliary stenting is a feasible option for patients who decline or are medically unfit for further elective endoscopic or surgical procedures. Close follow-up is mandatory to detect and treat late complications.

Difficult bile duct stones

Bile duct stones are routinely removed at time of endoscopic retrograde cholangiopancreatography (ERCP) after biliary sphincterotomy with standard balloon or basket extraction techniques. However, in approximately 10% to 15% of patients, bile duct stones may be difficult to remove due to challenging access to the bile duct (periampullary diverticulum, Billroth II anatomy, Roux-en-Y gastrojejunostomy), large (> 15 mm in diameter) bile duct stones, intrahepatic stones, or impacted stones in the bile duct or cystic duct. The initial approach to the removal of the difficult bile duct stone is to ensure adequate biliary sphincter orifice diameter with extension of biliary sphincterotomy or balloon dilation of the orifice. Mechanical lithotripsy is a readily available adjunct to standard stone extraction techniques and should be available in all ERCP units. If stone extraction fails with these maneuvers, two or more bile duct stents should be inserted, and ursodiol added to aid in duct decompression, stone fragmentation, and stone dissolution. Follow-up ERCP attempts to remove the difficult bile duct stones may be performed locally if expertise is available or alternatively referred to a tertiary center for advanced extracorporeal or intracorporeal fragmentation (mother-baby laser or electrohydraulic lithotripsy) techniques. Nearly all patients with bile duct stones can be treated endoscopically if advanced techniques are utilized. For the rare patient who fails despite these efforts, surgical bile duct exploration, percutaneous approach to the bile duct, or long-term bile duct stenting should be discussed with the patient and family to identify the most appropriate therapeutic option. A thoughtful approach to each patient with difficult bile duct stones and a healthy awareness of the operator/endoscopy unit limitations is necessary to ensure the best patient outcomes. Consultation with a dedicated tertiary ERCP specialty center may be necessary.

A new, secure drainage method from the cystic duct after choledocholithotomy using the cystic tube and the cystic clip: an experimental study

The effectiveness of the cystic tube (C-tube) and the cystic clip (C-clip) for primary closure of the common bile duct after choledocholithotomy was examined in 10 dogs, followed by an observation period of either 3 months (n = 6) or 1 year (n = 4). No early complications were observed in any of the animals either during or after surgery. The laboratory data were within the normal range during the observation period. No bile leakage or slippage of the C-clip was evident on fistulography from the C-tube in animals examined 5 days after surgery. The tube could be pulled out easily from the cystic duct without any bile leakage or slippage of the clip. A second operation to confirm late complications showed no adhesions around the common bile duct, no bile duct stenosis similar to the Mirizzi syndrome, and no cystic changes of the bile duct or biloma. Our newly designed C-clip for primary closure of the common bile duct after a choledocholithotomy therefore appears to be beneficial and applicable to clinical patients undergoing traditional as well as laparoscopic surgery.

Lithotripsy in the treatment of biliary stones

Noninvasive or minimally invasive techniques for the treatment of biliary stones have been significantly advanced in the past two decades. The least invasive, extracorporeal shock-wave lithotripsy, continues to be used successfully, not only at its earliest reported site of use in Munich, Germany, but also in numerous other centers in the world. Lithotriptors that utilize a spark gap electrode or other sources of energy to generate sound waves and imaging by radiographic and ultrasonographic targeting of stones have proved to be effective in fragmenting biliary stones (90% to 95%) that are too large or otherwise inaccessible to removal by endoscopic papillotomy. Stone clearance (53% to 90%) may require successive treatments and the removal of debris by transendoscopic or surgical means. The mortality is low (0.5%), and the post-treatment course is relatively uncomplicated in an elderly, high-risk group of patients.