Evaluation is in the form of a dye disappearance test followed by irrigation test. By using this sequence (with modifications) as a guide, the physician can frequently streamline diagnostic testing.

In irrigation test, a lacrimal irrigation cannula is passed into the punctum and advanced through the canaliculus to the lacrimal fossa. Clear water or saline is then irrigated through the cannula. If fluid passes into the nose without reflux out of the opposite canaliculus, the system is patent. If no fluid passes but it all comes back through either punctum, nasolacrimal duct obstruction is present.

Diagnosis is usually made by characteristic history and physical examination. Diagnosis can be confirmed by x-ray (80% of salivary gland calculi are visible on x-ray), by sialogram, or by ultrasound.

In one report, about 20% of individuals with mealtime syndrome had strictures upon sialography. For unknown reasons, strictures seem to be more common in females.

Strictures tend to be diagnosed based on difficulty with insertion and manipulation during sialendoscopy, or by sialography or ultrasound.

For diagnosis, measures of liver biochemistry and pancreatic enzymes are performed. Along with ruling out structural abnormalities, normally by performing an abdominal ultrasound and endoscopic retrograde cholangiopancreatography (ERCP). Measurements of bile transit when performing ERCP are taken to help evaluate different treatment options.

Sphincter of Oddi dysfunction is best diagnosed using manometry-an internal test done to measure the pressures within surrounding ducts to determine whether or not the muscle is functioning normally.

Ultrasound is the often chosen to examine the duct and determine the presence and size of any cysts or abnormalities. Fine-needle aspiration cytology can also be used to confirm the diagnosis.

Given that ascending cholangitis usually occurs in the setting of bile duct obstruction, various forms of medical imaging may be employed to identify the site and nature of this obstruction. The first investigation is usually ultrasound, as this is the most easily available. Ultrasound may show dilation of the bile duct and identifies 38% of bile duct stones; it is relatively poor at identifying stones farther down the bile duct. Ultrasound can help distinguish between cholangitis and cholecystitis (inflammation of the gallbladder), which has similar symptoms to cholangitis but appears differently on ultrasound. A better test is magnetic resonance cholangiopancreatography (MRCP), which uses magnetic resonance imaging (MRI); this has a comparable sensitivity to ERCP. Smaller stones, however, can still be missed on MRCP depending on the quality of the hospital's facilities.

The gold standard test for biliary obstruction is still endoscopic retrograde cholangiopancreatography (ERCP). This involves the use of endoscopy (passing a tube through the mouth into the esophagus, stomach and thence to the duodenum) to pass a small cannula into the bile duct. At that point, radiocontrast is injected to opacify the duct, and X-rays are taken to get a visual impression of the biliary system. On the endoscopic image of the ampulla, one can sometimes see a protuberant ampulla from an impacted gallstone in the common bile duct or the frank extrusion of pus from the common bile duct orifice. On the X-ray images (known as cholangiograms), gallstones are visible as non-opacified areas in the contour of the duct. For diagnostic purposes, ERCP has now generally been replaced by MRCP. ERCP is only used first-line in critically ill patients in whom delay for diagnostic tests is not acceptable; however, if the index of suspicion for cholangitis is high, an ERCP is typically done to achieve drainage of the obstructed common bile duct.

If other causes rather than gallstones are suspected (such as a tumor), computed tomography and endoscopic ultrasound (EUS) may be performed to identify the nature of the obstruction. EUS may be used to obtain biopsy (tissue sample) of suspicious masses. EUS may also replace diagnostic ERCP for stone disease, although this depends on local availability.

The most common and accurate way of diagnosing an individual with this anomaly is by MRCP (Magnetic Resonance Cholangiopancreatography) or ERCP (Endoscopic Retrograde Cholangiopancreatography). This test can demonstrate the presence of two separately draining ducts within the pancreas. Other tests can assist doctors with diagnosis, such as a CT scan and an MRI.

Some current treatment options are:

- Non-invasive:

- For small stones, hydration, moist heat therapy, NSAIDs (nonsteroidal anti-inflammatory drugs) occasionally, and having the patient take any food or beverage that is bitter and/or sour. Sucking on citrus fruits, such as a lemon or orange, may increase salivation and promote spontaneous expulsion of the stone.

- Some stones may be massaged out by a specialist.

- Shock wave therapy (Extracorporeal shock wave lithotripsy).

- Minimally invasive:

- Sialendoscopy

- Surgical:

- An ENT or oral/maxillofacial surgeon may cannulate the duct to remove the stone (sialectomy).

- A surgeon may make a small incision near the stone to remove it.

- In some cases when stones continually reoccur the offending salivary duct is removed.

- Supporting treatment:

- To prevent infection while the stone is lodged in the duct, antibiotics are sometimes used.

In boys, history and physical exam is adequate to make the diagnosis. In girls, VCUG (voiding cystourethrogram) is usually diagnostic. Other tests may include:

- Urine analysis

- Urine culture

- CBC, basic metabolic panel

- Renal and bladder ultrasound

Medication (to prevent spasms) or Sphincterotomy (surgical procedure to cut the muscle) are the standard treatments for sphincter of Oddi dysfunction. One or the other may be better based on the classification of the condition.

Choledocholithiasis (stones in common bile duct) is one of the complications of cholelithiasis (gallstones), so the initial step is to confirm the diagnosis of cholelithiasis. Patients with cholelithiasis typically present with pain in the right-upper quadrant of the abdomen with the associated symptoms of nausea and vomiting, especially after a fatty meal. The physician can confirm the diagnosis of cholelithiasis with an abdominal ultrasound that shows the ultrasonic shadows of the stones in the gallbladder.

The diagnosis of choledocholithiasis is suggested when the liver function blood test shows an elevation in bilirubin and serum transaminases. Other indicators include raised indicators of ampulla of vater (pancreatic duct obstruction) such as lipases and amylases. In prolonged cases the INR may change due to a decrease in vitamin K absorption. (It is the decreased bile flow which reduces fat breakdown and therefore absorption of fat soluble vitamins).

The diagnosis is confirmed with either an MRCP (magnetic resonance cholangiopancreatography), an ERCP, or an intraoperative cholangiogram. If the patient must have the gallbladder removed for gallstones, the surgeon may choose to proceed with the surgery, and obtain a cholangiogram during the surgery. If the cholangiogram shows a stone in the bile duct, the surgeon may attempt to treat the problem by flushing the stone into the intestine or retrieve the stone back through the cystic duct.

On a different pathway, the physician may choose to proceed with ERCP before surgery. The benefit of ERCP is that it can be utilized not just to diagnose, but also to treat the problem. During ERCP the endoscopist may surgically widen the opening into the bile duct and remove the stone through that opening. ERCP, however, is an invasive procedure and has its own potential complications. Thus, if the suspicion is low, the physician may choose to confirm the diagnosis with MRCP, a non-invasive imaging technique, before proceeding with ERCP or surgery.

Routine blood tests show features of acute inflammation (raised white blood cell count and elevated C-reactive protein level), and usually abnormal liver function tests (LFTs). In most cases the LFTs will be consistent with obstruction: raised bilirubin, alkaline phosphatase and γ-glutamyl transpeptidase. In the early stages, however, pressure on the liver cells may be the main feature and the tests will resemble those in hepatitis, with elevations in alanine transaminase and aspartate transaminase.

Blood cultures are often performed in people with fever and evidence of acute infection. These yield the bacteria causing the infection in 36% of cases, usually after 24–48 hours of incubation. Bile, too, may be sent for culture during ERCP (see below). The most common bacteria linked to ascending cholangitis are gram-negative bacilli: "Escherichia coli" (25–50%), Klebsiella (15–20%) and Enterobacter (5–10%). Of the gram-positive cocci, Enterococcus causes 10–20%.

In females, meatal stenosis can usually be treated in the physician's office using local anesthesia to numb the area and dilating (widening) the urethral opening with special instruments.

In boys, it is treated by a second surgical procedure called meatotomy in which the meatus is crushed with a straight mosquito hemostat and then divided with fine-tipped scissors. Recently, home-dilatation has been shown to be a successful treatment for most boys.

The histologic appearance is similar to mucoceles from other locations. The spilled mucin causes a granulation tissue to form, which usually contains foamy histiocytes. Ultrasound and magnetic resonance imaging may be useful to image the lesion. A small squamous cell carcinoma obstructing the Wharton duct may require clinical examination to be distinguished from a ranula.

Sialectasis (also termed sialectasia, or siadochiectasis) is cystic dilation of the ducts of salivary glands. It may be caused by salivary duct strictures or stones (sialolithiasis). It can also rarely be congenital.

A salivary gland fistula (plural "fistulae") is a fistula (i.e. an abnormal, epithelial-lined tract) involving a salivary gland or duct.

Salivary gland fistulae are almost always related to the parotid gland or duct, although the submandibular gland is rarely the origin.

The fistula can communicate with the mouth (usually causing no symptoms), the paranasal sinuses (giving rhinorrhea) or the facial skin (causing saliva to drain onto the skin).

The usual cause is trauma, however salivary fistula can occur as a complication of surgery, or if the duct becomes obstructed with a calculus.

Most parotid fistulae heal by themselves within a few weeks.

In order to prevent further cysts and infections from forming, the thyroglossal duct and all of its branches are removed from the throat and neck area. A procedure, known as the Sistrunk procedure, is considered to be the standard procedure and involves removal of portions of the hyoid bone and core tissue of the suprahyoid region. Cysts will often reoccur if the entire duct is not removed, so reoccurrence requires a wider range of tissue to be removed in a subsequent surgery.

Delaying the surgical procedure almost always leads to recurrent infections, which will continue to delay the needed treatment. The Sistrunk procedure has a reoccurrence rate of less than 5%, proving it is extremely effective at removing the majority of traces of the persistent thyroglossal duct.

Treatment involves an operation called a choledocholithotomy, which is the removal of the gallstone from the bile duct using ERCP, although surgeons are now increasingly using laparoscopy with cholangiography. In this procedure, tiny incisions are made in the abdomen and then in the cystic duct that connects the gallbladder to the bile duct, and a thin tube is introduced to perform a cholangiography. If stones are identified, the surgeon inserts a tube with an inflatable balloon to widen the duct and the stones are usually removed using either a balloon or tiny basket.

If laparoscopy is unsuccessful, an open choledocholithotomy is performed. This procedure may be used in the case of large stones, when the duct anatomy is complex, during or after some gallbladder operations when stones are detected, or when ERCP or laparoscopic procedures are not available.

Typically, the gallbladder is then removed, an operation called cholecystectomy, to prevent a future occurrence of common bile duct obstruction or other complications.

The lesion is usually present in children. Ranulas are the most common pathologic lesion associated with the sublingual glands.

The condition is usually self-limiting, and thus not indicated for surgery.

The term "duct ectasia syndrome" has been used to describe symptoms of nonpuerperal mastitis, possibly associated with nipple inversion and nipple discharge. In some contexts, it was used to describe a particular form of nonpuerperal mastitis coincident with fibrocystic disease, frequently involving pasty (coloured) nipple discharge, nipple retraction, retroareolar abscess and blue dome cysts. Abscessation is not very frequent but by some definitions recurrent subareolar abscess is merely a variant of duct ectasia syndrome - abscessation would be obviously more frequent with this definition.

Duct ectasia syndrome has been associated with histopathological findings that are distinct from a simple duct widening. In addition to nonspecific duct widening the myoepithelial cell layer is atrophic, missing or replaced by fibrous tissue. The original cuboidal epithelial layer may be also severely impaired or missing. Characteristic calcifications are often visible on mammographic images.

Periductal mastitis, comedo mastitis, secretory disease of the breast, plasma cell mastitis and mastitis obliterans are sometimes considered special cases or synonyms of duct ectasia syndrome.

Pancreas divisum in individuals with no symptoms does not require treatment. Treatment of those with symptoms varies and has not been well established. A surgeon may attempt a sphincterotomy by cutting the minor papilla to enlarge the opening and allow pancreatic enzymes to flow normally. During surgery, a stent may be inserted into the duct to ensure that the duct will not close causing a blockage. This surgery can cause pancreatitis in patients, or in rare cases, kidney failure and death.

An association with adenoma of the minor papilla has been reported.

Some mucoceles spontaneously resolve on their own after a short time. Others are chronic and require surgical removal. Recurrence may occur, and thus the adjacent salivary gland is excised as a preventive measure.

Several types of procedures are available for the surgical removal of mucoceles. These include laser and minimally-invasive techniques which means recovery times are reduced drastically.

Micro-marsupialization is an alternative procedure to surgical removal. Micro-marsupialization uses silk sutures in the dome of a cyst to allow new epithelialized drainage pathways. It is simpler, less traumatic, and well-tolerated by patients, especially children.

A non-surgical option that may be effective for a small or newly identified mucocele is to rinse the mouth thoroughly with salt water (one tablespoon of salt per cup) four to six times a day for a few days. This may draw out the fluid trapped underneath the skin without further damaging the surrounding tissue. If the mucocele persists, individuals should see a doctor to discuss further treatment.

Smaller cysts may be removed by laser treatment, larger cysts will have to be removed surgically in an operating room.