A series of cases suitable for Students

General techniques of analysis

BOWEL SYMPTOMS

Anatomical constraints in the abdomen

Routine teaching cases in the abdomen.

Complicated Medical Cases and syndromes

Exam images and clinical symptoms

Local manifestations of systemic disease

Bone disease

A few chest images

Radiology cases for Medical Students

General techniques of analysis
Bowel symptoms
Anatomical considerations in the abdomen
Routine teaching cases in the abdomen.
Complicated Medical Cases and syndromes
Images and symptoms
Local manifestations of systemic disease
Bone disease
A few chest images
Introduction to chest x-ray assessment

A Syndrome is a pattern in time and space. X-rays are mostly patterns in space and are interpreted for exam purposes in their clinical context. This isn't always possible with images from all sources and un-expected findings are frequently the area, where the trained observer can contribute.

The intention is to show patterns and systems for viewing images. This also assumes that examiners are attracted by connections between any image and some concept or historical detail.

With unexpected. images, you either get it right first time. Gestalt. or you need to analyse the image and the clinical detail, to recognise it.
Go for the sign or symptom with the shortest differential list.
Then refine with additional information from what you see or from the clinical history.

Try to remember all of these items. Then run the mouse over the image to change it.

An image, list or concept is always easier to interpret from a remembered structure. It's an ancient technique for remembering lists and goes back at least to the age of Aristotle.

Given that the physical method of collecting the image will affect its display, the image will be constrained by the anatomy and physiology. Thus the different size of the heart in diastole or systole will influence your decision as to whether it has enlarged since your previous examination.

Each region will have a number of features that you can name, seek and recognise. This is particularly true of the chest film.

Language is important. If you have a list of features to check, it will be easier to see them. The unique use of names in some environments allows locals to identify and name a range of features that people from other cultures may not see at all. In Medicine, it is called a Professional Vocabulary and the advantage of the often-occurring Latin or Greek is that the word-meanings are unchanged by contemporary fashions.

The interpretation will be affected by the innate physiology of vision.

The case is acute Colitis. Note the mucosal thickening, the lack of haustra and the shortening.

Colitis with sailor hat ulcers.
for further reading

Colitis Crohns with small-bowel involvement. Note the irregular involvement in the colon, skip lesions, and the string sign.

Extensive Small Bowel Crohns. The image does not show the gall-stones that were present and that might underscore the effect of the disease upon entero-hepatic circulation and biliary colloid stability. for further reading

Compare the appearance with this case of Radiation

The splenic flexure site of ischaemic colitis reflects the watershed of blood supply between superior and inferior mesenteric arteries. This can be seen from the Plain film or barium enema.
For further reading

This patient had been on broad spectrum antibiotics. The gross thickening of the mucosa is not accompanied by the classical appearance of sub-mucosal gas in pseudomembranous colitis, which is associated with Clostridium difficile. There was a Haemorrhagic colitis.
For further reading

The pattern of sub-serosal gas seen in Pneumatosis coli can be seen as different from the more intraluminal gas of necrotic mucosa in the above. The condition is thought to be associated with chronic obstructive airways disease. The sub-serosal location of the gas is better appreciated from the Ba. enema.

The appearance of Multiple colonic polyps may be linked in the examiners mind to sebaceous cysts (Gardener) or intracranial tumours (Kronkite Canada)

and the 5% incidence of Carcinoma of colon, in this case sigmoid colon.
For further reading

Barium studies should be viewed in the context that dependant parts fill with barium. The body of the stomach is anterior, which explains its double contrast appearance in a supine view.
Mesenteric attachments mean that as bowel gets distended it will be constrained to have its centre of mass on the line from DJ flexure to caecum. The visible long fluid levels in the erect view will often follow this line of attachment of the mesentery.

	Ascites	Portal hypertension. In ascites the soggy bowel floats medially, there is some separation of the ill-defined loops and loss of retroperitoneal planes. Note enlarged spleen. For further reading
		This was a control film for an IVU, revealing the cause for the abdominal pain, a gastric ulcer.

		Gastric ulcer, Note the distortion and uninterrupted mucosal folds that radiate from ( pulled into ) the ulcer crater. The interrupted mucosal folds and irregular raised edge of the tumour indicate carcinoma of stomach.
		Another lesser curve carcinoma. Note the featureless mucosal appearance of underlying gastric atrophy. Examiners will be tempted to link this with the related subjects of vitamin B12 neuropathy and cardiomyopathy.
		Ulcer symptoms and a feeling of fullness after meals may reveal a gastric Leiomyoma with the ulcer at its tip.
		Scarring produces the typical Trefoil deformity in duodenal ulcer.
		In small bowel ascariasis, you may see the barium in the gut of the parasitic worm.
		Duodenal and small bowel strongloides is a small worm, which infiltrates and inflames duodenum and proximal small bowel. It has a differential diagnosis with other proximal small bowel infiltrations, eg. Wipple. The jejunal mucosal thickening becomes more subtle further away from the duodenum.
		There is on this database a series of cases of Ileocaecal Tuberculosis Some of the images illustrate the retreat of the ileo-caecal junction towards the liver, secondary to the related fibrosis.

The medical history can be crucial and if interesting, will be a reason for the inclusion of the material by examiners.
In Zollinger Ellison syndrome, there is a great excess of acid secretion, secondary to a gastrin secreting tumour. Note the fluid-filled stomach and duodenum, an indication of hypersecretion. The dilated loops indicate the malabsortion that can occur, secondary to the hypersecretion of acid by the stomach and the resulting alteration of the normal alkaline Ph of the small bowel.

The use of enteric coated drugs can produce ulcers in the oesophagus, when some underlying condition causes hold-up. The following are both secondary to Slow K, enteric coated potassium supplements. The first stricture complicates mitral valve disease and the second was found in a patient with aortic valve disease.
This discussion is still relevant today since Diphosphonates, used to treat osteoporosis, can give rise to strictures and ulceration if released locally in high concentration.

Behcets colitis with neurological abnormalities, genital and mouth ulcers etc.

Hypertrophic osteoarthropathy, in Crohns disease

As with other areas, bone cases are chosen to reinforce general points of medical thinking.

You will get localised manifestations of generalised diseases or single foci of disorders where the radiology diagnosis might make a big contribution to the management. Biopsy of a stress fracture has occasionally resulted in tragedy where its histological appearance can falsely resemble a bone malignancy. It is better to make the diagnosis first and confirm it with direct questioning for abnormal excercise.

Recognition of the general type of benign or malignant bone tumour is an important skill. As usual, commonsense analysis supplies most of the features you will be expected to know. A benign lesion grows slowly and displaces rather than crosses bone or tissue boundaries.

The benign lesion (here; aneurysmal bone cyst) is more likely to be well-defined with a narrow zone of transition between normal and abnormal bone. Its long axis will be parallel to the bone, since the lesion will be around long enough to be affected by growth. The surrounding bone is displaced, but can be thinned enough so as to be almost invisible in some views.

Compare this lesion with a poorly delineated wide zone of transition between normal and abnormal bone, (an osteosarcoma).

You will have a higher suspicion of unexplained pain around the knee in a young adolescent, partly because of the pathology and partly because of the need to make an early diagnosis of osteosarcoma, if present. Consideration of both hip and knee is particularly important in the assessment of unilateral lower limb pain at this age.

Additional soft tissue mass outside the bone is an indication of a malignant tumour extending beyond a boundary. The age of the patient and the region of involvement will affect your analysis.

Chrondromata in flat bones have a high rate of malignant transformation, for example.

Paget's disease can increase the risk of osteosarcoma, otherwise rare in an elderly person.

Deafness, Pagets of skull
For further reading

neurological deficit charcot joint of the ankle.
For further reading

Anaemia, gastric atrophy in pernicious anaemia.

Anaemia, Hypernephroma

Anaemia, splenomegaly in Leukaemia

Common or curable disorders are also chosen for discussion by examiners, particularly if there is a typical feature in the clinical history that makes a diagnosis. In our catchment area, the cultural and nutritional aspects of the life of recent immigrants from India will influence the probability of the diagnosis of metabolic bone disease or tuberculosis.

Osteomalacia, nutrition or culture

Tuberculosis, Nutrition

Pagets Disease Common painful disorder.

Hyperparathyroidism, primary.
Chosen for interesting pathophysiology of calcium metabolism

The variation between inspiration and expiration can alter the appearance of the standard chest X-ray film. In this instance the two views were taken prior to scuba diving. The potentially dangerous air-trapping is easier to see in an expiratory film. The relation of structure and function is discussed elsewhere.

note the lost right heart margin in this case of right middle Lobar collapse

The silhouette sign indicates that the normally air filled lung is diseased and blurs the adjacent normal boundary.

The converse case with sparing of the middle lobe preserves the right heart margin only. Right upper and lower lobe suppurative pneumonia.

In this example, there is loss of the left diaphragm silhouette. If you followed the vessels in the left lung you would appreciate that the left hilar point is low (invisible) and then you'll notice the triangular density behind the heart that is the collapsed left lower lobe.

This, accompanied by a widened mediastinum will mean a probable underlying carcinoma in this smoker with left lower Lobar collapse

Lobar consolidation will change perfusion as the lung and its vessels respond to the altered ventilation.

In Radiology one must always remember that one pathology or appearance may imitate another.

The Ductal node of Tuberculosis imitates

The post-stenotic dilation of the pulmonary artery in Pulmonary stenosis

Part of the discrimination of masses in the chest involves their different center of radius, being, in this case, a little lower than the ductal node.

You can apply simple analysis to this image. There should be two margins to the diaphragm in the lateral view. The gas in the stomach can be identified, but there is no left diaphragm boundary above it. The densities behind the sternum and over the spine are different. The posterior density has a boundary that has a concave anterior margin. The posterior density is the left lower lobe. The concavity indicates some loss of volume, unsurprising where there is consolidation with loss of compliance. In this example, the loss of volume is significant and indicative of collapse of the left lower lobe.

	Film viewing strategies with particular attention to The Chest X-ray lung structure and function, a discussion Pulmonary oedema appearances A scheme for viewing The Abdomen
	A review of the Silhouette Sign

Ian Maddison June 2006