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Radiology for Finals

• It is likely that many of you will get asked about images in long/short cases in finals.
• You may be asked to quickly comment on any abnormality or to present a radiograph in full.
• It is all about systematic approach in order to check that we are safe on the wards as JHO's. Don't panic if the diagnosis is not obvious. Being able to spot abnormalities and comment that you need to ask for help from a radiologist is the important part.
• If you know a little bit extra it is a good way to impress the examiners.
• Remember physicians/surgeons are not radiologists, so are going to ask about the big classical signs.
• Plain films are likely to figure most highly, although particularly significant other images may occur.
• If the patient has a series of films get the right one and the right patient.
• They're unlikely to give anything that is not a big complaint/classic radiological sign. It may be NORMAL.
• Imaging is likely to feature highly in most patient management. Therefore think of it when asked: "how would you manage/investigate this patient?"

Below are Common films and Assessment/review of AXR and CXR's. Film links in brackets are to the radiology images on this MedicalFinals website. I will also try to link the images to the appropriate Surgical cases and Medical cases contained within the PasTest Surgical and Medical Finals books.

Below are a Range of Films You May Come Across ('*' means greatest chance of being asked to comment on or know):

Respiratory

• *Bronchial CA (+ Pancoast's) (CXR-fig6, CT-fig14,15)
• Pulmonary metastases
• *Pneumonia (several: lobar, bronchopneumonia and PCP) !! (CXR-fig3)
• Bronchiectasis/Cystic fibrosis (CXR-fig4)
• COPD (emphysema & chronic bronchitis spectrum)
• *Pleural effusion (uni/bilateral). (CXR-fig7)
• *Pneumothorax (standard and tension). Lung edge and black lateral to edge (no lung vessel markings). Mediastinal shift in tension seen as tracheal deviation. Seen best with expiratory erect CXR). (CXR-fig9)
• Lobar collapse
• Allergic Alveolitis (fibrosing lung)
• Pneumoconiosis (asbestosis and coal miner's)
• Malignant mesothelioma and pleural plaques (CT-fig18)
• *Sarcoidosis
• Pulmonary embolus (Invasive pulmonary angiography remains the gold standard. Computed Tomography Pulmonary Angiography (CTPA) is now performed in most centres. Ventilation-perfusion radio-nucleotide imaging scan plays a limited role in contemporary practise.) (CT-fig4)
• !!Silhouette Sign: loss of silhouette formed by lung adjacent to denser structures such as the heart.

Cardiovascular

• *Heart Failure
• Pulmonary hypertension
• HOCM
• ASD
• Coarctation of aorta (notching of the ribs due to development of collateral circulation. Seen in older patients)
• Pericardial effusion (globular appearance)
• Ventricular aneurysm (CXR-fig8)
• Valvular disease

Gastrointestinal

• Hiatus hernia (retrocardiac air-fluid level. Paraoesophageal(rolling) hernia)
• *Pneumoperitoneum (CXR-fig10) (can be small and subtle and takes on a crescenteric appearance. Remember Chaliditi's sign)
• *Small (XR-fig21,22), and large bowel obstruction (see distinguishing box below)

• Paralytic ileus & pseudo-obstruction (no cut off point)
• Sigmoid & Caecal Volvulus (coffee bean and empty caecum signs respectively. Sigmoid gives bird of prey sign on barium)
• Subphrenic abcess (usually under the right hemidiaphragm. Air/fluid level may be apparent)
• Oesophageal candidiasis
• Oesophageal web
• Oesophageal varices
• *Oesophageal carcinoma (raggy stricture, shouldering of stricture) (XR-fig1, XR-fig16)
• Oesophageal benign (corrosive) stricture (smooth stricture)
• Achalasia (CXR: widened mediastium, barium swallow: widened oesophagus)
• Pharngeal Pouch
• Gastric CA
• *Crohn's & ulcerative colitis (XR-fig2)
• *Diverticular disease (outpouching of bowel that are lined with barium, v obvious. Think is there other pathology present)
• *Colorectal cancer (the apple core lesion of an annular CA. Left side > right side of bowel) (XR-fig3,10,11,13)
• Colonic polyps (don't confuse with a residual faecolith in the bowel from poor preparation) (CT-fig12)

Hepatobiliary

• *Gallstone disease (USS first line. Stone apparent and gives off an acoustic shadow. ERCP, PTC and MRC also used)
• Hepatic metastases (seen well on USS and CT)
• *Pancreatitis (acute & chronic), (sentinel loop. Speckled calcification due to deposition in intra-pancreatic ducts. Contrast enhanced Ct scan needed to see necrosis).

Urogenital Tract

• Hydronephrosis
• Renal calculi (80% seen on AXR. Contrast this with 10-20% gallstones (XR-fig6). Beware of phlebolith)
• Bladder CA

Musculoskeletal

• *Osteoarthritis (Hip, Knee). Unilateral & bilateral. Before & After surgery. (Big 4 signs on XR) (XR-fig23)
• Osteoporosis (osteopenia, with vertebral crush #'s). (Crush # seen best on lateral spine. Increased thoracic kyphosis)
• *Ankylosing Spondylitis (sacroiliac joint fusion 1st. Bamboo spine. Syndesmophyte formations and calcification of longitudinal ligaments, squaring of the vertebrae) (XR-fig9)
• Paget's disease (Often incidental finding on pelvis/AXR - that would impress! Classically tibia bowing and skull bossing too, Seen as increases bone deposition with coarsening of trabecular pattern that appears fuzzy).
• *Bone metastases (lytic, sclerotic, expansile). (sclerotic - lighter than bone. Lytic - darker than bone (radiolucent).
• Rheumatoid arthritis (hands chiefly) (XR-fig8)
• Multiple Myeloma (pepperpot skull, pathological #'s)
• *Femoral neck # (intracapsular v extracapsular. Gardner's classification of 5 types of femoral neck #)
• Dynamic hip screw, hemi-arthroplasty and total arthroplasty of hip

Breast

• *Breast CA (big 3; micro-calcification, spiculation and distortion of normal breast contour)
• Breast cyst
• Fibroadenoma
• *Breast shadows, mastectomy & prostheses (uni/bilateral)
• Nipple markers

Neurology

• Brain neoplasm (macro and micro)
• Cerebral abcess
• Cerebral atrophy
• Cerebral infarct
• Multiple sclerosis (demyelinating)

Assessment of an AXR

• Technical: Date, Age, Name and Sex of Patient
• Type of AXR (supine, erect, decubitus)
  
• Intraluminal Gas: Size (<3cm small bowel, <5cm large bowel)
• Distribution of bowel loops (periphery - large bowel, central - small bowel)
• Bowel Markings (large - haustra, small - valvulae connivente)
• Ground glass/mottling - faecal shadowing.
  
• Extraluminal Gas: under the diaphragm (see: CXR-fig10)
• Biliary tree
• Bowel wall
  
• Calcification: any structures contain it?
  
• Soft Tissues & Bones: Psoas shadows
• Kidneys (T12-L2)
• Spleen and Liver
• Fractures
• Paget's
• Metastatses (sclerotic or lytic)
• Arthritis
  
• Iatrogenic/Accidental & Incidental
  
• Any man-made structures indicative of previous operations or other (stents, clips, IUCD, IVC filter).

Review Points

• Technical Specifics of the Radiograph
• Amount and distribution of gas
• Extra-luminal gas (evidence of)
• Evidence of calcification
• Soft tissue outlines and Bony structures
• Iatrogenic, accidental and incidental objects Radiology for Finals

Assessment of CXR

• Patient Details: Name, Age, Sex
• Film Details: Date Taken, Projection (PA, AP, L/R Lateral), single film or one of a series.
• Technical Details: RIP, Rotation, Inspiration, Penetration.
• Heart: Size, Border (start at aortic knuckle and work round to SVC) (see: eg. double heart border on CXR-fig1)
• Trachea (pull just off box to see best)
• Lungs: Hilia (size, level);  Fields (including apices and behind the heart). Only vessels, (end on respiratory tree and horizontal fissure to see)
• Diaphragm + costophrenic & costocardiac angles
• Mediastinum (size and shape)
• Bones (humerus, clavicle, scapula, ribs)

General points:

• A central tenant of imaging is that two views 90 degrees to one another are taken in order to localise structures/lesions (orthogonal views). For example, the PA and lateral chest films with a lung mass.
• One is able to distinguish a left and right lateral chest radiograph on observation. On the right lateral film the diaphragm can be seen to course from back to front without disruption. However, the left lateral film is disrupted by the intervening cardiac tissue, so not giving a continuous shadow.

The information below is to correspond with the major cases identified in the PasTest - Passing Surgical Finals book.

Goitre

• USS may show diffuse enlargement of the thyroid gland (see: CXR-fig2) and pressure on adjacent structures such as the trachea. Good at distinguishing solid from cystic structures.
• Radio-isotope scan identifies 'hot' and 'cold' spots representing nodules that either secrete (hot) or do not (cold).
• CT can help further delineate nodules and impingement, however the only way to definitely tell if the thyroid is malignant or not, is by an FNAC.

Parotid Gland Swelling

• Seen very well on axial CT and MRI.

Cervical Rib

• CXR (unlikely to get this)

Breast Carcinoma

• Standard CXR: loss of breast shadow (mastectomy or rarely absent breast). Also identify prosthesis as round, well delineated soft tissue shadow. Nipples can appear as small round densities which must be distinguished from other lung mass (esp, bronchial CA). Repeat film with nipple markers if in doubt and compare.
• Remember that a malignant pleural effusion is a relatively common complication so look for it if notice breast shadow absent.
• All women 50-64 (soon to be 69) invited to attend 3 yearly mammography. Views taken (mediolateral and craniocaudal views). Mammography a special technique using x-rays. Under 40-45 year olds mammography of little value as glandular breast tissue: adipose ratio higher and difficult to detect masses. These women need an USS.
• CA Features: Microcalcification
• Spiculation (spider like)
• Loss of regular border of breast

** calcification does not always mean cancer.

Fibroadenoma

• Smooth, usually single round density that may calcify.

Hepatomegaly/Splenomegaly

• AXR: diffuse soft tissue (grey) shadow extended below costal margin. USS: good images.

Large Kidney

• AXR: normal kidney 3-3 and half vertebrae in length in T12-L2 region. May see much bigger soft tissue shadow. Can cause displacement of adjacent structures.
• USS/CT: very clear images. Look for cystic change responsible for large kidneys.

Abdominal Masses/Ascites

• Seen well on USS and CT, but unlikely to ask to look at these.
• Ascites gives the appearance of a 'grey haze' on AXR as fluid in the peritoneal cavity.

Inguinal/Femoral Hernia

• AXR: These can be seen (esp. if large) as bowel loops (maybe distended) within the LIF or RIF.

Femoral Aneursym

• Arteriography is the gold standard for this and other arterial aneurysms but this does not mean it is what is used in practice. USS may demonstrate aneurysms well as can MR angiography.

Peripheral Vascular Disease

• Arteriography before and after angioplasty (XR-fig19,20). Know the names of the main arteries of the leg.

Testicles

• Everything to do with testicles is invariably seen on USS as they are superficial, covered in thin skin and soft tissue only. Varicocele seen as a 'bunch of grapes'.

AAA

• AXR: May be seen incidentally as calcification indicates internal diameter of vessel.
• USS first line: abdominal aorta should be 1.5-2.0 cm depending on the location. Greater than 3cm is abnormal. 3-4.5cm needs annual USS observation (surveillance), 4.5-5.5cm needs it 6 monthly. Greater than 5.5cm requires elective repair in most circumstances.
• Complicated or incidentally found on CT (CT-fig17), where a thrombus may be seen within the aneurysm.

Hip OA

• XR: loss of joint space, subchondral sclerosis, subchondral bone cysts (black appearance as air/fluid content) and osteophyte formation at the joint margins. (XR-fig23)

Knee XR:

• As for hip above. Medial compartment loss of joint space >> genu valgus clinically.

RA

• XR: (XR-fig8) loss of joint space. Periarticular erosions, periarticular osteoporosis. Soft tissue swelling. RA patients get systemic osteoporosis too.

** osteoporosis cannot be seen on XR. If there is bone loss it needs to be > 15% before detectable in which case it is osteopenia.

The information below is to correspond with the major cases identified in the PasTest - Passing Medical Finals book.

MI

• CXR: usually very little. May indicate potential cause for MI.
• ECHO and Cardiac Catheterisation may be undertaken.
  • ECHO: structural integrity, valve function and ejection fraction.
  • CC (Cardiac Catheterisation): vessel patency with view to CABG/PIC.

IE (Infective Endocarditis)

• ECHO: Valve vegetation and destruction

Bronchial CA

• CXR: (CXR-fig6, CT-fig14,15)
  • coin lesion,
  • area of consolidation (especially if fails to resolve),
  • Lobe collapse (intrabronchial lesion),
  • Pancoast's apical mass +/- rib destruction.

** standard protocol to have CT of thorax and of liver and adrenals (for metastatic disease)

!!CXR shown in a patient that clinically has a Horner's Syndrome - look at the apices for a Pancoast's bronchial CA.

COPD:

• Bronchovascular markings may be more evident. Overexpansion with flattened diaphragms.
• CXR: depends to some extent on which end of the spectrum of chronic bronchitis-emphysema present. 50% will have no CXR findings. Hyperexpansion of lungs (more than 10 posterior or 6 anterior ribs, flattened diaphragm). Emphysema may be seen as bullae. If asked what further imaging one would like: high resolution CT scan identifies the bullae vividly.

Chronic Liver Disease

• USS: shrunken liver +/- splenomegaly from portosystemic hypertension. Doppler's allow assessment of flow direction in vein and artery. If following same direction = portosystemic hypertension.

IBD - UC

• AXR: Acute toxic megacolon: dilated large bowel loops, characteristically the transverse colon
• BE: drain pipe/lead pipe colon (no haustral markings).

IBD - Crohn's

• Small Bowel Series: 4 big signs.
  • String sign (of Kantor),
  • Rose thorn ulceration (barium sitting in deep fissures),
  • Bowel loop separation (inflammed bowel irritates nearby loops which move away),
  • Cobblestone mucosa.

Multiple Myeloma

• Pepperpot Skull, Multiple Pelvic deposits. Radioisotope bone scan reveals multiple increases uptake areas.

Stroke

• CT: to distinguish haemorrhage (20%) from infarct (80%). Infarct may not be revealed for several days.
• Carotid angiography, USS dopplers and MR angiography may all be used in trying to identify a carotid stenosis. If clinically a murmur, do ECHO for potential emboli source in heart.

CCF (5 big radiological signs. * perfect question)

• Upper lobe venous diversion
• Perihilar oedema ('bat's wings')
• Bilateral pleural effusions
• Cardiomegaly
• Kerley B lines (horizontal lines at the level of the cardiophrenic angles)

Pleural Effusion

• Small vs. Large
• Unilateral vs. Bilateral
• Meniscus at the lateral aspect.
• Large pleural effusions will give the impression of a complete white out of the lung (Differential diagnosis = pneumonectomy).
• You may see the chest drain in situ.
• If the line is straight there is fluid and air (ie, traumatic pneumothorax or iatrogenic on draining effusion).
• A small effusion will need an USS to confirm it.

Fibrosing Alveolitis

• Cannot specifically diagnosis FA. It is the same as other fibrosing lung disease; fine reticulonodular shadowing (dots and lines).

TB

• CXR: TB favours the apices of the lungs, hence the review area of the apices on inspecting a CXR. TB lesions may cavitate - giving a central 'black' area with a fibrosed 'white' exterior. (CXR-fig5 shows unusual Miliary Shadowing)
• Look at age and name of patient given its increased prevalence in the old and foreigner.

Spot diagnosis

• Acromegaly: Large spade-like hands on XR. Cardiomegaly on CXR.
• Marfans: Long, slender hands with spinderly fingers (arachnodactylyl).
• Pepperpot Skull: Multiple Myeloma (pathological #'s too). (Note: 'Pepperpot skull' is a description given to multiple lucencies on the skull x-ray and can occur in other conditions such as hyperparathyroidism.)
• Pituitary Tumour: Widened sella turcica on lateral skull.
• Scleroderma: Calcinosis seen on hand XR at the pulps.
• Ank. Spondylitis: Bamboo spine (due to squaring of the vertebrae), calcification of the longitudinal ligaments. Sacroileitis over the ileopectoneal lines (*first sign). (XR-fig9)
• Paget's Disease:
  • Plain XR's: pelvis, tibia and skull favoured locations.
  • Disorder of bone resorption/deposition.
  • 'Fuzzy' areas of XS bone.
  • Radio-isotope scan: shows areas of high bone turnover which takes up the isotope.
• Osteoporosis:
  • DEXA (dual energy x-ray absorptiometry).
  • Get T and Z Readings.
  • T is overall bone density.
  • Z compares it to age and sex matched controls.

BY: Ian C Bickle, PRHO, Royal Victoria Hospital, Belfast.