In absence of ultrasonic duct dilatation and minimally deranged LFTs, MRCP is safer and preferred over ERCP as evaluation prior to intervention.

In absence of ultrasonic duct dilatation and minimally deranged LFTs, MRCP is safer and preferred over ERCP as evaluation prior to intervention.

EUS is a better option for detecting stone disease

I agree with Dr Darisetty. EUS is the best option in this condition.

Just do an intraoperative cholangiogram and if you find a stone, explore the bile duct.

ERCP, EUS, MRCP are overkill.

I agree with Dr. Santosh that EUS is the best option.

Diagnostic ERCP if positive then therapeutic

If  GB surgery is not planned, then MRCP is certainly a good first option, and then if negative EUS definitely. In today's world of increased scrutiny of what we do, less invasive is the best choice. Initial ERCP in the absence of evidence of obstruction is more and more difficult to defend. If GB surgery is planned, then without evidence of obstruction, intraoperative cholangiogram is best.

As a surgeon who does laparoscopic surgery on GB and CBD, as well as ERCP, I'd suggest operative cholangiogram for mildly elevated LFTs and a normal diameter CBD. This is a low probability scenario for CBD stones and does not warrant an ERCP. The complication rate will be higher for an ERCP than an operative cholangiogram, and if the ERCP was for nothing, that makes it even harder to "swallow." MRCP and EUS are nice if you have it available, but cannot manage what you find. If you're going to remove the gallbladder anyways, then operative cholangiogram is the most accurate and least morbid. If you are not planning on a cholecystectomy, then MRCP and EUS are more appropriate, given their lower morbidity than a diagnostic ERCP.

Cholecystitis itself may cause light deranged LFT without CBD dilation, even bilirrubin elevation, due to local CBD edema. Moreover, many drugs and steatosis may also elevate LFT. 

I agree with Dr. David Scheeres, however if you are not experienced doing intraoperative cholangiogram (more and more common nowadays), make sure you have a good fluoroscopy setup and ask for assistance. The dilemma here is If you find something - you may either explore it laparoscopically or ligate the cystic duct and send later for ERCP. If the endoscopist cannot access the papilla, then you are in trouble. Another option is to leave a biliary 7F catheter going transcistic and transpapillary for later ERCP access. Sometimes we schedule for the endocopist go to the OR once we made the diagnosis to perform ERCP just after we finish lap chole, in the same anaesthetic procedure. 

Otherwise go for a MRCP first.

As a HPB surgeon who has practiced in a wide variety of settings, I agree with Drs. Scheeres and Bonin in that if the patient is heading for the Operating Theater anyway, the most efficient and efficacious way to handle this issue is laparoscopic cholecystectomy/intraoperative cholangiogram/laparoscopic common bile duct exploration and clearance. Unfortunately not everyone is comfortable with those options so I would propose the following:

If the patient is not a candidate for surgery then MRCP is probably the best single, noninvasive test to detect an obstructing CBD stone. Yes, it does not help you manage the stone but it helps you apply ERCP only to those patients with a positive finding thus decreasing the number of patients exposed to the invasive procedure to only those likely to benefit from it (improving the risk:benefit ratio in the process). If MRCP is not available then endoscopic ultrasound is a good alternative.  EUS can be quite specific but is also quite operator dependent so that the interpretation may differ from exam to exam unless there is only one operator at your institution. Also since ultrasound is best read dynamically, the pictures are only marginally useful for later comparison or iinterpretation. If EUS is not available then serial transabdominal u/s with an interval ranging from 24 to 72 hours depending on the patient's symptoms. This type of interval testing can give powerful evidence for or against bilibary obstruction when combined with appropriate lab data.

If the expertise or facilities for lap CBDE are not available then postoperative ERCP for patients with positive intraoperative cholangiograms has been shown to be efficacious and safe. It also limits the use of ERCP to those patients likely to benefit and, as above with MRCP, favorably alters the risk:benefit equation. Lastly, if neither lap CBDE or ERCP are available then patients with CBD obstruction will have to undergo open CBDE. Luckily this will not be a large proportion of patients since this is still a considerable operation.

In this situation, if you have this option, EUS is the best way to decide if an ERCP+ES is indicated or not. MRCP is an other option but it can miss sludge and little stones

 I'm agree with Dr Frank Cannizzo: the most efficient and efficacious way to handle this issue is laparoscopic cholecystectomy/intraoperative cholangiogram/laparoscopic common bile duct exploration and clearance. Probably transcystic approach can resolve the CBD stone, but if is not possible, we can perform ERCP+ES in the immediate postoperative periode. With this approach, we  avoid innecessary preoperative ERCP  and choledocotomy.

I agree that EUS is more sensitive and specific than MRCP. What we try and do is consent the patient for EUS, and proceed to ERCP with just a top-up of sedation if a stone is found.  This assumes that the cholecystectomy will follow without delay.  If there is a significant likely delay, then ERCP and sphincterotomy can prevent the next attack of cholangitis or pancreatitis, but this is really not the best way to approach this.  Lap exploration of the cbd is not as widespread as it might be, whereas endoscopic methods are widely available.  The most common causes of mild elevation of liver enzymes are, of course, fatty liver, alcohol, hepatitis, drugs etc. It is a good idea to rule these out!

I agree that EUS is a good choice since it is a cost effective strategy in patients with low to intermediate risk for CBD stone. In our study we can proceed to ERCP without fluoroscopy if the stone is less than 1 cm in diameter in the same sedation.

in our institution have MRCP by which it is possible to rule out stones over 3mm. But do agree to use EUS if available.previously ihave used synchronous approach. ERCP prior to Lap Chole.

Often this question is answered depending on the local resources available.  MRCP can be useful, but almost always misses sludge and small stones in the CBD. Many guidelines suggest that in patients with small stones of up to 2 mm in the GB and slight transaminase elevation, one should just proceed to GB surgery. If EUS is available it is always useful and can more accurately locate small CBD stones or sludge.  That still begs the question of should a pre-operative ERCP be done, since small stones and sludge will normally pass through a non-compromised biliary sphincter. The reality is that all humans create and pass small stones and sludge, which we documented far too many years ago from random stool specimens collected from random people on the streets of New York City. Problems only develop when the stones/sludge cannot be passed. Regardless of the availability of MRCP or EUS, given the skill in the surgical community and timely availability of ERCP in most hospitals, this should able to be easily taken care of during surgery, with ERCP within 24 hours if needed.

Although there is a reasonable chance there would not be stones found in the cbd, and even if there were we dont know what proportion of these would pass through without any clinical problems, we would still investigate with MRCP +/- EUS. If suggestive of cbd stones i would go for ercp to clear the duct prior to surgery , although clearly intra op transcystic clearance is an alternative