Radiology Flashcards
A 24-year-old lady with no past medical history presents with varicose veins of the calf in the distribution of the long saphenous vein. They are cosmetic with no associated skin changes, however she is unhappy with their appearance and wishes surgery.
Hand held Doppler
Hand held Doppler will allow one to assess the saphenopopliteal and saphenofemoral junctions as sites of incompetence; if both these are intact one can then trace the long saphenous listening for reflux to assess whether a major perforator is involved. Only if the hand held Doppler is non-diagnostic, incompetence is at the saphenopopliteal junction or the site of reflux is anatomically unusual would one proceed to a pre-operative duplex scan.
A 46-year-old lady presents with varicose veins in the distribution of the long saphenous vein of the right leg. She attributes their onset to a fractured ankle when she was 40-years-old. There are some skin changes with haemosiderin deposits.
Duplex scan
Duplex scanning is indicated in this lady with primary varicose veins because she has had a fracture which would have been associated with several weeks of immobility and then reduced mobility, which may have caused a DVT. The purpose of the duplex scan will be to assess the integrity of the deep veins in addition to assessing the site of venous reflux; if the deep veins are thrombosed then one cannot remove the superficial veins without risking venous gangrene. In the scenario of superficial reflux and deep venous thrombosis treatment will be by compression hosiery.
The tourniquet test is very unreliable and so should not be used to delineate the site of venous incompetence, one may as well just look at the leg.
Venography is used in some institutions but has the disadvantage of being painful, uses ionising radiation and contrast consequently should be avoided.
Some would promote the pre-operative scanning of all veins by duplex, but this is unrealistic outside of the commercial sector due to time constraints on scanners and technicians.
A 76-year-old man with a past history of stroke, myocardial infarction, pacemaker insertion, claudication and type 2 diabetes on glicazide presents with a five day history of increasing pain in his left leg. He currently cannot walk, sleeps in a chair for short periods only and requires regular analgesia when awake. He has no pulse to feel in either groin or below.
CT angiogram
This man has no groin pulse and so does not have an inflow to either leg, leading one to believe his disease is in his aorto-iliac segment. This can be assessed by transbrachial angiography or CT angiography (MRA is precluded because of the pacemaker).
Duplex does not image the intra-abdominal vessels well and tests of the foot (ABI, Doppler) will not tell you where the anatomical site of this man’s problem lies. Once the anatomical site is identified surgery can then be considered, bearing in mind the man’s co morbidities.
A 76-year-old lady with undiagnosed atrial fibrillation presents with a two hour history of a cold and painful left leg. On arrival her leg is pulseless below the groin, cool WITH decreased sensation She has minimal movement of her toes which are pale. Her right leg is entirely normal. She has no history of claudication.
Immediate femoral embolectomy
This lady has an acutely ischaemic limb which is already has neuro-ischaemic changes. Her lack of pre-event vascular history and normal pulses in the other leg suggests that her vessels are probably normal and that a cardiac origin clot has blocked the common femoral - profunda/superficial femoral origin (the common femoral pulse is palpable). Her surgery should be done as soon as possible, within 6 hours of the onset of symptoms. The procedure can usually be done under local anaesthesia. The anaesthetist can help with sedation and treatment of her AF.
Due to the potential for profound swelling there should be a very low threshold for performance of fasciotomies - if you think they are required to be done. Thrombolysis can be used in other groups, but in the elderly it has many complications and so is not advised.
Pre-operative investigations here will waste time and are very unlikely to change your management and so are not recommended.
A 76-year-old man presents with resolving left sided hemiplegia; auscultation of the carotid arteries reveals a bruit on the right.
Carotid duplex
This man is most likely to have a carotid artery stenosis and should therefore be imaged using carotid duplex. This technique combines ultrasound with waveform analysis. Duplex can be used to image neck masses, for example, nodes, aneurysm, tortuous carotid vessels. Duplex is best employed in the assessment of carotid and vertebral arteries. This technique is safe and has a comparable accuracy to angiographic assessment in skilled hands.
A 76-year-old man presents with sudden onset of right sided blindness, auscultation of the carotid arteries reveals no bruits. He is not hypertensive.
CT brain
Amaurosis fugax is a transient monocular visual loss that develops over a few seconds and usually clears within a few minutes. Failure to resolve within 24 hours is analogous to a stroke. Therefore he requires an urgent CT to exclude an embolic or haemorrhagic stroke and review by a neurologist.
A 45-year-old man presents with a sudden severe headache.
CT brain
The description given is classical of a subarachnoid haemorrhage and usually results from the rupture of an intracranial aneurysm into the subarachnoid layer. The severe headache results from chemically induced meningitis. A CT scan within 24 hours of the onset of symptoms is the investigation of choice and is 95% sensitive.
Le fort fracture
The CT demonstrates fracture to both maxilla, the right zygomatic arch and the bones associated with the nose.
This is known as a Le Fort fracture, of which there are three types.
Tongue carcinoma
The diagnosis is carcinoma of the right side of the tongue.
This is responsible for the ill-defined mass which is extending across the midline.
The loss of the normal midline septum is important, as a hemi-glossectomy cannot be performed.
