Grainger & Allison's Diagnostic Radiology Essentials

Urethra

Urethra: Benign Disorders Congenital Anomalies Müllerian duct cysts Usually the caudal Müllerian duct is obliterated apart from its distal tip (which forms the verumontanum) ▸ incomplete obliteration may lead to the formation of cysts between the bladder and rectum which…

Prostate

Prostate: Benign Disorders Acute and Chronic Prostatitis Definition The same organisms that produce acute prostatitis can cause chronic prostatitis ▪ Healthy adults: E. coli and staphylococci are the predominant causative organisms ▪ Immunocompromised patients: unusual organisms are more commonly seen…

Bladder

Miscellaneous Bladder Conditions Congenital Anomalies Bladder agenesis A rare condition which is usually associated with absence of the urethra and other congenital abnormalities ▸ there is marked upper tract dilatation and renal dysplasia which is incompatible with life Bladder hypoplasia…

Kidneys

Renal Parenchymal Disease Glomerulonephritis Definition A proliferative and necrotizing abnormality of the glomeruli ▸ it is usually primarily renal but may be part of a systemic vasculitis (e.g. SLE, PAN, Goodpasture's or Wegener's) US/CT/MRI Acute: symmetrically swollen kidneys ▸ no…

Paediatric Gastrointestinal Disorders

Abdominal Wall Defects Omphalocele Definition: incomplete formation of the embryonic ventral abdominal wall leads to a congenital midline anterior abdominal wall defect around the umbilicus (the umbilical cord inserts at the tip of the defect) ▪ Larger omphaloceles (containing liver…

Plain Abdominal Radiograph

Abnormal Gas Distribution Pneumoperitoneum Definition Free intra-abdominal gas – it usually indicates perforation of a viscus (it is often a peptic ulcer – a perforated appendix rarely demonstrates free gas) ▪ Other causes: bowel obstruction ▸ appendicitis ▸ bowel ischaemia…

Peritoneum, Mesentery and Omentum

Benign Diseases Ascites Definition >100 ml of free fluid within the peritoneal cavity due to benign or malignant causes ▪ Transudative fluid: portal hypertension/cirrhosis/heart failure/nephrotic syndrome ▪ Exudative fluid: infection/peritoneal carcinomatosis ▪ Blood: trauma/tumour rupture/haemorrhagic diathesis ▪ Purulent fluid: intestinal perforation…

Spleen

Miscellaneous Splenic Conditions Normal variants and congenital anomalies Splenunculus: this represents ectopic splenic tissue of congenital origin ▸ they can be single or multiple and are usually found at the splenic hilum ▸ they have similar imaging (and enhancement) appearances…

Pancreas

Congenital Abnormalities Embryology The pancreas develops in two parts from the endoderm of the primitive duodenum Dorsal part: this is the first part to appear, initially appearing as a diverticulum from the dorsal wall of the duodenum ▸ it forms…

Biliary

Methods of Investigation Magnetic Resonance Cholangiopancreatography (MRCP) Technique Heavily T2-weighted coronal oblique fast spin-echo sequence to obtain source data (aligned along the plane of the common bile duct [CBD]) ▪ Stationary water appears as areas of high SI and adjacent…