Some X-ray methods for the generalist

Section 1.13 describes WHO's basic radiological system. Here are some methods which are not part of that system. If you have a radiographer, he will be familiar with them. Most of them assume that your machine has a screen, but it has not, you can still do a barium swallow. Always use a grid which will improve the definition. Most screens have a grid which you can slide into place.

Carcinoma of the oesophagus is common in much of the developing world, so you will find a barium swallow, which is quite easy, particularly useful. A barium meal is more difficult, but with reasonable practice you can learn quite a lot from one. A barium enema is more trouble, and is less often needed. Cystoscopy (23.3) may give you the information you need, and is cheaper than an IVU. We do not describe catheterizing the ureters, and so retrograde pyelography is not described either.

INTRAVENOUS UROGRAM (IVU) [s7](intravenous pyelogram or IVP) INDICATIONS. (1) If a patient has moderate impairment of his renal function, to see if it has a purely renal cause, or is due to an obstructive uropathy, particularly a hydronephrosis or a ureteric stricture, especially in areas where S. haematobium is endemic. (2) To see if a mass is renal. (3) To assess the function of his other kidney, when you consider referring him for nephrectomy. (4) Renal trauma (67.1). (5) Renal or ureteric stone (23.12).

CONTRAINDICATIONS. (1) Measure his blood urea. If it is over 10 mmol/l (65 mg/dl), an IVU will probably fail because the dye will not be excreted in adequate concentration to be visible. It is certainly not worth doing if his blood urea is over 17 mmol/l (100 mg/dl. (2) Renal failure. (3) Hepatic failure, which may be aggravated. Cardiac failure; there is a risk of arrythmia. (4) Dehydration. (5) Infancy. (6) The first trimester of pregnancy is a relative contraindication, but the danger is minimal. (7) Any previous reaction to contrast medium or other allergic disease. (8) Multiple myeloma.

PREPARATION. Starve him overnight and give him an aperient to empty his gut. Air will not spoil the film, but a mixture of air, fluid and faeces will. Don't give him an enema. If the IVU is urgent, do it without preparation.

CONTRAST MEDIUM. Use ''Urografin' 60% or ''Conray 420'. Rarely, he may have a reaction, so make sure you have ready 0.5 ml of adrenalin 1/1000 and promethazine 25 mg for intramuscular injection. Cardiac arrest has followed injection, so be prepared to resuscitate him (3.5).

FILMS. Use 18[mu]24 cm for his bladder; 24[mu]30 cm for his renal area; 30[mu]40, 35[mu]35, or 35[mu]43 cm for his whole abdomen.

METHOD. The following method minimizes the number of plates needed. The views are all AP; 60 mA at 68 KV should be enough for a 60 kg adult.

Lay him supine on the X-ray table. Take a preliminary view of his abdomen and pelvis on a 30[mu]25 cm plate, before giving the contrast medium. Give him 40 ml intravenously as quickly as possible.

At 3 minutes take a 25[mu]30 cm plate of his kidneys. Then compress his lower ureters. If his calyces are obviously normal at 3 minutes (be quick, it will need 5 minutes in the developer, fixing and washing), you can omit the 15 minute film.

At 15 minutes take another view of his kidneys. At 20 minutes release the compression and then quickly take a 35[mu]43 cm plate to show his ureters and bladder.

At 30 minutes ask him to empty his bladder, and then take a small plate to show his residual urine.

If the function of his kidneys is impaired, so that there is little excretion in the standard films, repeat them at 2 hours, and if necessary at 6 hours.

Fig. 34-9 SOME UROLOGICAL X-RAYS. A, in a micturating cysto- urethrogram the patient's bladder is filled with contrast medium, and a film taken while he is passing it. B, and C, two types of obstruction. D, in a retrograde urethrogram contrast medium is injected up his urethra from below (this shows an oblique view.) E, a false passage shown in a retrograde urethrogram.

RETROGRADE URETHROGRAM [s7]FOR A STRICTURE PRINCIPLE. If you inject contrast medium up a patient's urethra from below, you can outline his distal urethra up to the face of the stricture.

INDICATIONS. (1) Stricture of the urethra. (2) Congenital anomalies. (3) Prostatic abscess. (4) Fistulae. (5) False passages.

CONTRAINDICATIONS. (1) Acute infections of the urinary tract. (2) Recent attempts at bouginage which will increase the risk of bacteraemia.

CONTRAST MEDIUM. (1) A contrast medium especially designed for urethrography, such as ''Umbradil Viscous U'. If necessary you can probably dilute it with an equal volume of water and still get good pictures. (2) If necessary, use media designed for urography, such as ''Hypaque' 45% and urografin 60%.

CAUTION ! Don't use barium, or an inorganic iodide. Contrast medium readily passes into the surrounding vessels.

METHOD. Using aseptic precautions, insert a 16 Ch Foley catheter for 5 cm only into his urethra. Gently inflate the bulb with 1 or 2 ml of sterile water. The expanded bulb will now fix the catheter in his fossa navicularis. Fix a length of tubing to the catheter. You can now position him more easily, and be further from the radiation yourself when you inject the contrast medium and expose the plate.

Inject the medium and take an oblique film while he lies on the X-ray cassette. Avoid extravasation, if you can. If his bladder is reasonably filled, you can follow a retrograde urethrogram with a micturating cystourethrogram.

The membranous urethra is separated from the penile urethra by a line, which runs from the junction of the upper third and the lower two-thirds of the pubic ramus on one side, to a corresponding point on the other side.

MICTURATING CYSTOURETHROGRAM [s7]FOR A STRICTURE PRINCIPLE. This shows up the proximal face of a patient's stricture, and will also show bladder neck stenosis. His bladder must be filled with contrast medium to begin with. If you can pass a catheter through his urethra, you can fill it that way. If he has a suprapubic catheter in place and is able to micturate through his urethra (unusual), you can fill his bladder through that.

INDICATIONS. (1) Strictures. (2) Suspected abnormalities of the bladder neck. (3) The assessment of vesical diverticula. (4) Cysto-ureteric reflux.

CONTRAINDICATIONS. (1) Acute infections of the urinary tract. (2) Recent attempts at bouginage, which will increase the risk of bacteraemia.

CONTRAST MEDIUM. (1) 40 ml of 60% ''Urografin' in 400 ml of saline. Or, (2) a 250 ml bottle of 30% ''Urografin'. (3) 400 ml of 12.5% sodium iodide with 0.1% sodium metabisulphite. This is the cheapest. The sodium iodide must be suficiently pure; small quantities of fluoride in it can be disastrous.

METHOD. This depends on whether or not he already has a suprapubic catheter in place.

If he has a suprapubic catheter, empty his bladder through it. Using an intravenous drip set or a large syringe, fill it through his suprapubic catheter with 300 to 400 ml of

contrast medium until he has a strong desire to pass urine.

Take an erect oblique AP film at 80 mA and 80 kV while he is standing to pass urine. Or take an oblique film in the lying position; there will be less blur due to movement. Use a bucky screen and a grid cassette.

If he has a ureteric catheter in place, fill his bladder through that.

BARIUM SWALLOW INDICATIONS. (1) Dysphagia. (2) Carcinoma of the oesophagus (32.24). (2) Post-corrosive strictures (25.15).

CONTRAST MEDIUM. (1) Thin barium (''Gastrografin' or ''Endographin'). Water-soluble media must not be aspirated. (2) Barium sulphate; thicker than for a barium meal, yet not so thick as to aggravate an obstruction.

CAUTION ! Don't use barium carbonate, which is highly poisonous.

METHOD. Stand him in front of the X-ray screen facing you. If you don't have a screen, take films only. Ask him to fill his mouth with contrast medium, but not to swallow it until you ask him to. He can either drink from a feeding cup (which is less likely to spill in the dark), or suck the barium through a stiff 5 mm plastic tube inserted through a hole in the top of a plastic container, as used for tablets. The mixture of air and barium that he swallows will produce an informative ''phase contrast' film.

Adjust the X-ray machine to provide a narrow vertical aperture. Then ask him to swallow and watch the barium pass. Repeat the process and expose a plate as he swallows.

Do the same thing while he stands laterally with his hands above his head. You should be able to see all but the upper end of his oesophagus quite easily. If necessary, take two oblique views, a lateral fiew and an AP view.

Carcinoma of the oesophagus causes a narrowing with an abrupt start and an irregular rounded shoulder; above it the oesophagus is either not dilated, or only a little dilated. The lumen through the tumour is irregular and is typically rat- tailed, and you can see the end of the stricture. You should be able to demonstrate 90% of carcinomas with simple screening. An ordinary PA film may show widening of the mediastinum. Be sure to use a long plate to get his whole oesophagus on to it, and don't cone down.

If no screening is available, a mouthful of contrast medium and one large film will usually show the tumour.

If you are not sure how long the stricture is, try a repeat film with a head-down tilt. This is important in deciding how long a Celestin tube needs to be (32.24).

Achalasia (uncommon) shows as a ''bird's beak' at the bottom end of a greatly dilated oesophagus. Take oblique films.

Corrosive oesophagitis produces a stricture which is usually long and irregular.

A post-cricoid web (rare in Africa) is associated with iron deficiency anaemia and is a narrow web behind the cricoid cartilage. Centre a lateral film on the cricoid.

Fig. 34-10 SOME BARIUM SWALLOWS. A, a postcricoid web (lateral view). B, achalasia of the cardia. C, carcinoma of the oesophagus.

BARIUM MEAL INDICATIONS. (1) Bleeding from the upper gastrointestinal tract, oesophageal varices (endoscopy is likely to be preferable). (2) Peptic ulcer. (3) Carcinoma of the stomach. (3) Carcinoma of the head of the pancreas. (4) An upper abdominal mass suspected of being gastric.

METHOD. Do a barium swallow first with thin barium. Ask him to stand facing you. Then give him thicker barium.

Adjust the aperture of the X-ray machine to let you see his entire stomach. Stand him facing you, and ask him to drink enough barium to about half fill his stomach while he continues to stand facing you (one contributor uses much less barium). Then screen him in this position and in the left oblique position (he should look beyond your left shoulder), or use the right oblique position.

STOMACH. Watch peristalsis carefully. Does barium pass through normally all the way to his pylorus?

Suggesting carcinoma[md]an immobile area, a persistently irregular surface, a consistent filling defect (this makes carcinoma very likely).

Suggesting a gastric ulcer[md]an ulcer, usually on the lesser curve, in the distal half of his stomach.

Expose 1 to 3 plates, asking him to hold his breath as you do so.

To look for a hiatus hernia you will need to raise his intra-abdominal pressure: (1) Ask him to lie down and give the table a 20[de] head-down tilt. Push the barium up to his fundus, and expose another plate. Or (2) ask him to lift his legs off the table and cough.

DUODENUM. Note if there is delay in the passage of barium through his pylorus: it should start passing at 1[nd]5 minutes. Use the special attachment which will exclude all X-rays except those in a 10 cm circle. Turn him to face obliquely to your right as far as is necessary for you to see his pylorus and duodenal loop. Expose plates as the barium passes. You may be able to recognize a deformed duodenal cap while you screen him, but you will see scarring or a duodenal ulcer more easily on the dry films. With experience, you will recognize enlargement of the duodenal loop (as by carcinoma of the head of the pancreas).

Pyloric delay makes a duodenal ulcer or a carcinoma of the distal antrum likely, and is an indication for laparotomy.

Fig. 34-11 ARRANGEMENTS FOR A BARIUM ENEMA. You will probably be able to demonstrate the patient's large gut as far as his hepatic flexure, without much difficulty; his ascending colon is more difficult. Note that you are wearing goggles and an apron.

1, an X-ray screen, grid, and X-ray plate; these are usually in an under-couch bucky tray. 2, a 30 Ch flatus tube. 3, a standard plastic Y-connector. 4, artery forceps. 5, a 2 l stainless steel douche can. 6, a Higginson's syringe. Kindly contributed by James Cairns and Rogers Mungalu (Radiographer at St Francis Hospital, Katete, Zambia).

BARIUM ENEMA INDICATIONS. (1) Suspected amoebic strictures. (2) Carcinoma of the large gut. (3) Diverticulosis (rare in most of the developing world). (4) A mass which might be colonic. (5) Ulcerative colitis, tuberculosis, Chron's disease etc.

CAUTION ! A barium enema should follow proctoscopy and sigmoidoscopy, which will often establish the diagnosis more easily and cheaply.

CONTRAINDICATIONS. (1) Complete, incomplete, or impending intestinal obstruction. (2) Rectal biopsy immeditely preceeding the enema.

EQUIPMENT. An X-ray machine with a screen. A 2 litre douche can. 2 metres of 30 Ch rubber or plastic tube. 2 large artery forceps. A Higginson's syringe. A grid on top of the X-ray plate.

METHOD. Prepare the patient with an enema, and a thorough washout (not merely an enema, and not necessary in children), within the previous 12 hours, and keep him on fluids during this time. Use barium/air contrast with the equipment in Fig. 34- 11.

CAUTION ! Manipulate the flatus tube with gloves. Have toilet paper and a bedpan ready[md]it may be required urgently!

Lay him supine on the X-ray table, and ask him to flex and abduct his hips. Protect his gonads. Lubricate the flatus tube well with KY jelly, and push it through his anus, as far as it will go easily. Ask him to extend his legs on to the table. Inject barium and air, as required, to show his large gut up to his caecum. Inject a fair amount of barium first, and follow this by pumping air with the Higginson's syringe to move the barium proximally, clamping and releasing the tubes as necessary. Instil some barium, and then some air. You will probably be able to demonstrate his large gut as far as his hepatic flexure, without much difficulty; his ascending colon is more difficult. The limiting factor is the distension of his large gut with barium and air, and the urge to defaecate that this produces. If he feels much discomfort, wait 2 or 3 minutes and try again with more barium and more air.

Watch the movement of barium and air on screening, and expose plates of critical areas. Before he defaecates, which he is usually keen to do without delay, take a standard abdominal X- ray after removing the screen and keeping the grid in place. Expose another plate after evacuation. The film of barium left on his mucosa will often give the clearest picture.

Finally, remove the flatus tube and let him pass the contents of his gut into the bedpan.

EVALUATION