Parotid and Submandibular Sialograms :

Water-soluble contrast medium of high iodine density has been used in these examinations, but it is possible to use oil-based media as well. The parotid gland is the largest of the salivary glands and lies below the external auditory meatus, between the mandible and the sternomastoid muscle. The structures contained in the parotid gland include the external carotid artery, the retromandibular vein and, more superficially, the facial nerve. The parotid duct is about 5 cm in length and opens into the mouth opposite the second upper molar tooth. The submandibular gland lies in the floor of the mouth, in the submandibular triangle; its duct is also about 5 cm in length and opens via a narrow orifice onto the frenulum of the tongue. Conditions such as calculi, infection, trauma and neoplasia can be investigated by sialography.

   Antero-posterior Barium Study of Stomach and Duodenum :

The stomach can be said to have two surfaces: an anterosuperior and a posteroinferior. The anterosuperior surface lies under cover of the left costal margin and is in contact with the diaphragm. Laterally it is in contact with the spleen and medially with the liver. The posteroinferior surface, or 'stomach bed', has a number of important relations: the pancreas, left kidney, left suprarenal gland, splenic artery, spleen, transverse mesocolon and the greater omentum. Both surfaces are covered with peritoneum, with the greater sac in front and the lesser sac behind. The level of the pylorus is at the L1/L2 disc space (transpyloric plane), with the stomach empty and the patient supine. The duodenum is about 25 cm long, is in a fixed position, has no mesentery and is only partially covered with peritoneum. The C-shaped curve of the duodenum encloses the head of the pancreas. The duodenum is divided into four parts: the first or superior part begins at the pylorus and ends at the neck of the gall bladder; the descending or second part runs down the right side of the vertebral column to L3 and is crossed by the transverse colon. The common bile duct and pancreatic duct join to open into the medial side of this part of the duodenum. The third or horizontal part crosses the L3 vertebra anterior to the inferior vena cava and ends in the fourth part which lies in front of the abdominal aorta. The ascending or fourth part turns upwards to L2 where the duodenojejunal flexure occurs. The flexure is fixed by a fibromuscular band, called the suspensory ligament of the duodenum (Treitz), which arises from the diaphragm. Various projections and techniques in differing positions are used to demonstrate the whole of the stomach and duodenum on a barium meal examination.

   Antero-posterior Barium Follow-through :

The length of the small intestine is approximately 5-7 m, with arbitrary divisions into jejunum and ileum. The diameter of the jejunum is around 25 mm and that of the ileum 20 mm. The plicae circulares begin in the second part of the duodenum and their maximum size and number occur in the middle portion of jejunum. They then diminish and finally disappear about the middle of the ileum. When performing follow-through examinations, it is important to know the characteristics of the barium used so that physiological abnormalities can be recognized in addition to any gross pathology. The second film shows the ileum and the ileocaecal region. The ileocaecal valve often protrudes into the caecum and may produce a filling defect which can be mistaken for a tumour. The terminal ileum may manifest diseases such as regional enteritis (Crohn's disease). Malabsorption can also be investigated by a follow-through examination and two main groups are found: the first group with radiological features due mainly to steatorrhoea and the second group with disease-specific radiological features. Points to look for are: dilution of contrast, rapid transit time, dilatation of small bowel and abnormalities of the circular folds. To test for lactose intolerance (disaccharide deficiency), lactose can be added to the barium and the resulting changes noted.

   Large Bowel Enema-Double Air Contrast :

The commonest area in which lesions (particularly polyps) are missed is in the sigmoid colon because of the position of its loops in the pelvis. Ideally, digital examination of the rectum and sigmoidoscopy should be performed prior to an enema examination as a high percentage of pathological lesions present in the last 20 cm of the large bowel.

   Oral Cholecystogram (Prone Oblique View) :

The contrast used here is calcium ipodate, given orally. It is absorbed from the intestine and concentrated in the gall bladder. It is normally necessary to administer contrast intravenously (e.g. meglumine iodipamide) to demonstrate the detailed anatomy of the intra- and extrahepatic ducts. The gall bladder is situated under the right lobe of the liver and is attached to it by connective tissue. The inferior surface is covered with peritoneum continuous with the liver. The cystic duct joins the common hepatic duct to form the common bile duct just below the porta hepatis, but this junction may be considerably lower. If this occurs, the cystic duct will lie in the right free margin of the lesser omentum. The mucous membrane of the cystic duct is thrown into a series of folds, giving rise to the appearances of the so-called spiral valve of Heister. The oral cholecystogram examination has been replaced by ultrasound.

   Endoscopic Retrograde Cholangiopancreatogram :

Endoscopy of the stomach and duodenum is performed and cannulation of the ampulla of Vater is attempted under direct vision. Water-soluble contrast is then gently introduced into the common bile duct from below and outlines the biliary and pancreatic ducts. The selectivity of the injection will depend on the position of the junction between the biliary and pancreatic ducts. The pancreatic duct lies closer to the posterior surfaces of the pancreas and runs right through the gland, giving small ducts at right angles. The body of the pancreas is separated from the stomach by the omental bursa and the tail lies in contact with the spleen between the two layers of the lienorenal ligament. The accessory pancreatic duct drains from the head of the pancreas and may join the main duct or open separately into the duodenum. Complications of this technique include fever, a rise in serum amylase and septicaemia.

   Intravenous Pyelogram (Urogram) :

The right kidney is usually smaller, further from the midline and lower than the left kidney. The splenic hump on the left kidney is just a variant of normal and should not be confused with a mass. The papillae indent the minor calyces and are the site for the termination of the collecting tubules (ducts of Bellini). High-dose urography often with nephrotomography is used in the investigation of renal failure, ureteric obstruction, emergency examination following trauma and for the differential diagnosis of renal masses.

   Seminal Vesiculogram (Vasogram) :

The seminal vasogram was performed under general anaesthetic and demonstrates the proximal vas deferens and the seminal vesicles, both of which drain via the ejaculatory ducts on the colliculus seminalis (verumontanum). As this study is performed under non-physiological conditions, there is reflux of contrast into the bladder which would not occur during ejaculation as the bladder neck is then closed.