Computer generated transcript

Warning!
The following transcript was generated automatically from the content and has not been checked or corrected manually.

NATIONAL SURGICAL TEACHING SOCIETY ABDOMINOPELVIC CT INTERPRETATION Ed Neil-Gallacher 26/9/23Ed (Neil-Gallacher) Radiologist, Carlisle+Whitehaven (Cumbria) Trained across southern England; Kent, Surrey, Sussex, London+Cambridge Cross-sectional fellowship in emergency and cardiothoracic imaging Likes: -holidays -cat videos -radiologyKEY LEARNING OBJECTIVES ⮚ Image acquisition ⮚ Systemic approach to CT review ⮚ What to look for ⮚ Learn some key image findingsAcute CT…How we do it…‘IRMER’ ( yawn ) • ‘justify’ or ‘approve’ the scan…(shortly)ulations 2017. We must first • Computed Tomography uses x-rays to acquire ‘slices’ through the body. • X-rays are emitted and traverse the body • The detectors opposite (on the other side of the patient) quantify the attenuation coefficient of the tissues they pass through • The density of tissue in a particular volume can be calculated • The slices can be added together to get an anatomical picture.Summary • Maths.Sir Godfrey Hounsfield https://www.youtube.com/shorts/bmgxzg7ynfov=ih_mTjMrrb0 Chose a scale that reflects the four basic x-ray densities in the body: air = -1000 HU (Hounsfield units) fat = -60 to -120 HU water = 0 HU compact bone = +1000 HUCT requests • Broadly - the younger the patient, the more vulnerable their tissues are to x-ray induced mutations (+by extension cancer) • We must therefore quantify the risks and benefits in each case • If radiology agrees it is clinically necessary to proceed to CT - rather than wait, do nothing or image by a different modality – then give us a clue!CT requests • Contain a brief summary that is factually true, i.e without using a trigger word or exaggerating to scare radiology into submission • Tell us the patient’s essential medical and surgical history, i.e if they’ve had a partial colectomy or a cholecystectomy (or whatever else) please write it down, as it saves us valuable time • Finish the request by asking us a question. It should stop us from waffling (I make no promises)Remember one of our maxims…Case 1 CLINICAL INDICATION: ?obstruction right illiac fossa pain, some distention to right side, vomiting. ?obstruction ?ischaemic bowelAnother radiology phrase… Fat is your friend Look for inflammatory fat stranding Case 1 • Cholecystitis • Stone? • Distension? • Wall thickening? • Mural hyperenhancement? • Pericholecystic oedema?Fat strandingCholecystitis • Look for complications… • Is there a calcified stone and where is it? • Has the GB perforated? • Is there a drainable collection? • Is there biliary obstruction? Signs of pancreatitis?On the subject of fat…Case 2 CLINICAL INDICATION: ?pancreatitis of free fluid suggestive of pancreatitis related to gallstones. CT-report advised pancreatic designated CT-imaging to investigate further. MRCP not tolerated due to claustrophobia. Bilirubin 19, ALP 213, ALT 268, Amylase initially 777 now 379. Thank youCase 2Case 2This vs thatCase 2 • Acute pancreatitis • Interstitial oedematous (IEP) vs necrotising (NP)? (Revised Atlanta classification) • Look at pancreatic enhancement (ideally after 1 week cf oedema-related hypoenhancement) • Fluid collection? • Gallstones? • Ascites?Case 3 CLINICAL INDICATION: ?INTESTINAL OBSTRUCTION PATIENT WITH RECURRENT VOMITING, TYMPANITIC PERCUSSION ABDOMINAL NOTES. ?INTESTINAL OBSTRUCTIONCase 3 • Poll O’ClockCase 3 • SBO • Look for a transition point (occasionally easier said than done) • Free gas? • Wall enhancement preserved? • Pneumatosis intestinalis? • PV gas? • Closed loop?SB faecesCase 4 CLINICAL INDICATION: ?ca primary patient with SOB, CTPA showed @@@@@@@@@@@@@, primary unknown, background breast ca /remission and baretts oesophagusCase 4 • PollCase 4 • Liver metastases • Often silent and discovered incidentally • Generally hypoattenuating (can be hypervascular with some primaries – RCC, thyroid, neuroendocrine) • cf. abscesses which often present with RUQ pain and feverHhhmm? (Poll) A BCase 5 ?appendicitis 60 year old woman, started with periumbilical pain, fever, and nausea on friday, pain migrated to RIF on saturday, a/w diarrhoea and worsening pain in RIF, CRP 100, no prev abdominal surgeries, no known ovarian pathology, ?appendicitisCase 5 • EasyAppendicitis • Dilated > 6 mm • Appendicolith? • Mural hyperenhancement? • Mural congruity? • …fat stranding? • Collection? • Perforation?Uh-oh • Surgeons and their complications…Case 5a • Rare (developed countries). Mainly bacterial, usually in the setting of comorbidities • Infection; abdominal sepsis • Immunocompromised • IVDU • Trauma • ERCP • Biliary disease • Inflammatory bowel disease • PUDCase 6 CLINICAL HISTORY Abdominal pain. Fresh PR bleeding. Vomiting. Weight loss. Peritonitis.Case 7 • CLINICAL HISTORY • Trauma to the left upper quadrant. Did somersault and landed on to pole with impact on the left upper quadrant. Presents with left upper quadrant pain and pain on examination. To rule out thoracic/abdominal injury.Case 8 • CT neck CT thorax CT abdomen CT pelvis/CT aorta • Clinical history:? Abdominal aortic aneurysm? Renal stone.. New onset of right lower quadrant pain with palpable pulsatile mass possible lower limb and ischaemic symptoms of blood in the urineSUMMARY • Think about the indication and determine what test would be best to confirm your diagnosis • If acute CT is indicated then in your request be concise, factual/ accurate (don’t exaggerate) AND tells us some useful history • Ask us a question so we can tailor our report (or we’re prone to wordiness) • If safe to do so, giving i.v contrast can be v helpful – but it is not essential to look for bowel obstruction, perforation, ruptured AAA etc (risk vs benefits)SUMMARY • Start with axial images (so you get used to reviewing in this plane) • ‘Window’ the scan to optimize the pictures, for free gas use a ‘lung window’ • FAT IS YOUR FRIEND - look for fat stranding/ oedema • Is something looks strange look at a previous scan (Old is gold)SUMMARY • Be systematic • compare with a structure you recognize out what you’re looking at then Good luck!Resources • Google images, Radiopaedia • Ed.Neil-Gallacher@ncic.nhs.uk THANK YOU! ● QR code and survey link ● Stay tuned for… upcoming lectures insert here ● Follow the link to NSTS website for further learning resources ● Promotion from sponsors ● Feedback link/QR, example on right