SPOTS Dr Prashanth G R3 – Radiology Govt.Medical College Baroda 10-07-08
This middle aged patient presented with progressive right sided sensorineural hearing loss. T2 axial image and T1 coronal post contrast image are shown.
Right acoustic neuroma (schwannoma) On the T2 axial image there is a round mass of mixed signal in the right cerebellopontine angle. It causes slight displacement of the brain stem medially, and extends into the auditory canal on the right. The edge of the mass makes an acute angle with the petrous bone. On the T1 coronal image there is intense enhancement. The tail within the canal is clearly seen.
Acoustic neuromas account for 80% of cerebellopontine angle tumours. They are more common in females and in patients with neurofibromatosis, especially of the central type (NF type 2). The main differential diagnosis is a meningioma. These account for 15% of CPA masses and also enhance brightly. However they do not tend to extend into, or arise from, the canal and often have a broad base with a less acute angle between tumour and bone (the ‘dural tail'). There may be associated bony sclerosis
2 . A 35 yr old woman presented with a short history of painful swelling of the left eye. Her vision was intact but the eye was congested on examination and slight proptosis .
Findings The left lateral rectus muscle demonstrates abnormally high signal on T2w images. The other muscles are not involved. The muscle enhances markedly following gadolinium.
Orbital pseudotumour Inflammatory condition of the intraorbital soft tissues, of unknown aetiology, characterised by a lymphocytic infiltrate. It accounts for 25% of cases of unilateral exopthalmos in adults, Predominantly affects young females. It presents with painful ophthalmoplegia, proptosis and chemosis. The involved tissues may include: Retrobulbar fat in 76% Intraocular muscles in 57% Optic nerve in 38% Uveal scleral area in 33% Lacrymal gland in 5%
There are two forms: Tumefactive form. Pseudotumour behind the globe, either a discrete mass or poorly defined. Optic myositis form (as seen here). Enlargement of muscles. The main differential is thyroid eye disease, which is said to spare the muscle insertions on the globe, and which affects the inferior and medial rectus muscles first.
CO poisoning • There are bilateral symmetrical paired areas of increased signal intensity in the basal ganglia. • Differential • Asphyxia - carbon monoxide poisoning, strangulation or drowning (NB. however on CT these conditions usually show hypodense areas and low signal on MRI T1 weighted images). • Wilsons disease • Leigh disease (a rare disease of childhood - lesions are hypodense on CT). • HIV infection. • CJD
A 30yr old female pt presented with galactorrhoea. MRI was done to look for a a pituitary adenoma.
This 34 year old female patient has a long history of chronic renal failure, complicated by hypercalcaemia. Her thyroid function tests were within normal limits. US of the neck was performed.
Tertiary hyperparathyroidism, parathyroid adenomata. Tertiary hyperparathyroidism results from prolonged secondary hyperparathyroidism, when hyperplastic tissue becomes autonomous, or an adenoma develops.
Avascular necrosis of the humeral head - The “snowcap sign” an early feature of avascular necrosis.
This 76yr old man presented with a painful upper arm following a minor fall a few weeks earlier.
Paget's disease of the humerus & pathological fracture This film demonstrates both phases of Paget's disease. The initial lytic phase consists of an advancing front of resorption. This starts at one end of a long bone and advances to the other, and is characteristic. The sclerotic phase follows, and may coexist. This is due to new bone formation and remodelling. This new bone is however not as structurally sound as normal bone. The other major complication occuring in long bones is that of sarcomatous change into chondrosarcoma or osteochondroma. ( 1-5% ) and may present with worsening pain or a pathological fracture.
A pre-operative chest radiograph was obtained for a 55 year old woman undergoing surgery for bowel cancer.
This young man suffering from chronic anaemia was referred with an upper respiratory tract infection, to exclude a secondary pneumonia.
Thalassaemia major, extramedullary haematopoesis The PA film demonstrates bilateral mediastinal masses. The left and right heart borders are clearly visible, as are the hilar vessels, implying that the masses are posterior. Additionally the bones appear markedly abnormal. The ribs are expanded anteriorly, and are osteopaenic with a coarse trabecular pattern.
This elderly lady presented to the emergency department with abdominal pain.
Gas in the biliary tree Causes Previous instrumentation or surgery: ERCP and sphincterotomy for bile duct stones and biliary bypass surgery (eg. choledochojejunostomy). Passage of a stone through the common bile duct may allow reflux of air. Fistula: due to inflammation secondary to stones. The stone may pass into the duodenum, or into the transverse colon. Tumour may also cause a fistula. Infection: emphysematous cholecystitis produces air in the gallbladder, and this may also outline the biliary tree. It is commoner in diabetics.
This patient presented with a history of change of bowel habit and lower abdominal pain. There had been a brief episode of rectal bleeding a few weeks earlier, and dysuria.
Crohn’ s disease with colovesical fistula Conditions that may cause colonic strictures. Infiltration (Primary carcinoma and metastases, such as from breast) - MC Inflammation (Diverticular disease and inflammatory bowel disease) Infection (Tuberculosis - usually caecal, and lymphogranuloma venereum - rectal) Ischaemia (Mesenteric ischaemia) Irradiation (Radiotherapy for pelvic tumours) Infestation (Amoebiasis)
This 20 year old man presented after two episodes of bloody diarrhoea. He had no previous history of note, and was otherwise in good health. A small bowel examination was reported as normal.
Varicosis coli - a rare congenital syndrome that may be asymptomatic.
This 62 year old woman presented to the emergency department with one week's history of increasing abdominal pain and distension & a long history of chronic constipation.
This 46 year old male presented with a scrotal mass. Ultrasound was performed to assess this further.
Adenomatoid Tumour of Epididymis Extratesticular neoplasms are unusual and usually involve the epididymis. The most common neoplasm is the adenomatoid tumour - 32% It is commonly found in patients aged 20-50, is generally unilateral, solitary, well-defined, oval in shape, and rarely measures > 5 cm in diameter.
This 44 year old patient was found to have microscopic haematuria at a routine examination. Ultrasound had demonstrated an abnormality of the left kidney, and so CT was performed.
Multilocular cystic nephroma MLCN ( multiticular renal cyst , cystic nephroma ) - a rare, non hereditary cystic neoplasm with a well defined capsule and multiple septa dividing epithelial lined cysts. It has a biphasic age and sex distribution, being more common in males from 2 months to 2 years, and females in middle age (40-60 years). The haematuria often correlates with herniation of the mass into the renal pelvis, which is a well recognised feature. US and CT demonstrate a multioculated cystic structure unless the cysts are very small or filled with myxomatous material, when it can not be differentiated from any other solid renal mass. The septa may enhance on CT. CT may demonstrate the intrapelvic or perirenal extension. The tumour is generally benign but with variable growth rate and size. It is occasionally malignant with local recurrence and pulmonary spread.
Schmorl’s node Protrusion of intervertebral disc material through a break in the subchondral bone plate, with displacement of this material into the vertebral body. Schmorl's nodes, also termed cartilaginous nodes, may occur in numerous conditions. They may result from any disease or condition that leads to weakening of the cartilaginous endplate or subchondral bone of the vertebral body. Scheuermanns disease (juvenile kyphosis) Trauma Hyperparathyroidism Osteoporosis, other metabolic conditions Infection Neoplasm
Colloid cyst of the third ventricle Colloid cysts are smooth, round lesions of endodermal origin, typically located at the foramen of Munro in the anterior aspect of the third ventricle. They are usually filled with gelatinous material and cholesterol crystals. These cysts generally occur in adults and account for approximately 1% of all intracranial tumors. On NCCT, the majority of colloid cysts are hyperdense to brain tissue. A thin rim of enhancement is visible after intravenous contrast administration. Due to the proteinaceous nature of its contents, a colloid cyst is typically hyperdense on T1-weighted MR images and hypointense on T2-weighted MR. They are managed surgically because they tend to cause hydrocephalus by obstructing cerebrospinal fluid flow at the third ventricle.
Pott's puffy tumor ( frontal sinusitis, frontal bone osteomyelitis, subgaleal abscess ) & epidural abscesses