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X-Ray Spotters for General Surgery PG Final Viva

Complete Theory, FAQ & Tricks-to-Remember Guide

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HOW TO APPROACH ANY X-RAY SPOTTER IN VIVA

Identify the view - AP/PA/erect/supine/lateral Airway & soft tissue Lines and tubes Whiteness/blackness (densities) Abdomen/bones peripherally Your diagnosis - state confidently Say what you see (describe first, conclude after) Explain findings systematically Etiology list Differential Extra findings (incidental) Treatment/management next step Additional investigations Immediate emergency action if needed Long-term management Summary

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1. FREE GAS UNDER DIAPHRAGM (Pneumoperitoneum)

What to Say First

"This is an erect chest X-ray / erect abdomen X-ray showing a crescent of radiolucency (free gas) beneath the right hemidiaphragm, indicating pneumoperitoneum."

Key Radiological Features

Causes (Mnemonic: "PP CAN Be Traumatic")

• Perforated peptic ulcer (MC cause, ~50%)
• Perforated bowel (diverticulitis, Ca colon, typhoid, appendix)
• Crohn's disease perforation
• After laparoscopy/laparotomy (iatrogenic - normal for 7-10 days post-op)
• Necrotising enterocolitis
• Bowel ischaemia
• Trauma (blunt abdominal trauma)

FAQ Viva Questions

1-2 mL of free gas can be detected on erect CXR (most sensitive plain film view)

Erect CXR - patient kept upright for 10 minutes before taking film (allows gas to rise)

Right side - because the liver fills left subphrenic space, and stomach air on left can mimic. Also gas is more easily distinguished against liver homogenicity on the right.

Left lateral decubitus X-ray - gas will collect over the liver (right side up view)

Perforated peptic ulcer (duodenal > gastric)

Both inner and outer walls of bowel loop are visible = gas on both sides = pneumoperitoneum (or gas-filled loop adjacent to another)

Graham's patch repair (omentoplasty) - gold standard emergency Definitive - Truncal vagotomy + pyloroplasty (if H. pylori treated)

Tricks to Remember

• "Right cupola under right dome" - gas goes to highest point = right subdiaphragmatic
• Rigler's = Right-side sign (pneumoperitoneum on supine)
• Always look for associated findings - surgical emphysema, absent liver dullness clinically
• Post-laparoscopy gas persists for up to 7-10 days - do NOT call emergency

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2. PELVICALYCEAL STONE (Urolithiasis - Kidney Stone)

What to Say

"This is a plain X-ray KUB (Kidney-Ureter-Bladder) showing a radio-opaque shadow in the right/left pelvicalyceal system at the level of L2/L3 vertebra consistent with a renal calculus."

Key Features

• 90% of renal stones are radio-opaque (contain calcium)
• 10% radio-lucent: uric acid, xanthine, cystine (partially), matrix stones
• Staghorn calculus = fills entire pelvicalyceal system = branched stone

Stone Composition & Radiopacity

FAQ Viva Questions

Renal stone: overlies renal shadow, moves with respiration in opposite phase to gallstones, lies more medial Gallstone: lies over liver area, often multiple, laminated

3 sites (Mnemonic: PUJ, Crossing iliac vessel, VUJ)

1. Pelvi-ureteric junction (PUJ) - most common
2. Crossing of iliac vessels
3. Vesico-ureteric junction (VUJ) - narrowest point, most painful

IVU or CT-KUB (NCCT - gold standard - detects ALL stones regardless of composition)

Proteus mirabilis (urease-producing bacteria), also Klebsiella, Pseudomonas

PCNL (Percutaneous Nephrolithotripsy) - gold standard

Tricks to Remember

• "Stones 1-4-5": Stones < 4mm pass spontaneously; 4-5mm: 50/50; > 6mm: need intervention
• ESWL works best for stones < 2cm in kidney
• Bilateral staghorn = emergency (potential acute renal failure)
• Uric acid stones: treat with allopurinol + urine alkalinization (sodium bicarbonate)

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3. BLADDER STONE

What to Say

"This is an X-ray pelvis/KUB showing a radio-opaque shadow in the midline suprapubic region overlying the bladder area, likely a vesical calculus (bladder stone)."

Key Features

• Located midline, in pelvis, suprapubic
• May be single or multiple; laminated appearance
• Associated with bladder outflow obstruction (BPH most common in elderly)

FAQ Viva Questions

Developing countries: Endemic bladder stone (dietary - low phosphate, high cereal) - seen in children Developed: Secondary to bladder outlet obstruction (BPH), infection, foreign body

Phlebolith: has central lucency ("bull's eye"), located more laterally, smaller, multiple Bladder stone: central, denser, moves with position change (on fluoroscopy)

Endoscopic: Cystolitholapaxy (TURBL - transurethral cystolithotripsy) - most common Open: Cystolithotomy - for very large stones

Always do TURP for BPH after removing bladder stone

Tricks to Remember

• Bladder stone = midline, suprapubic, moves on positional films
• Ureteric calculus = follows course of ureter (paravertebral → crossing iliac vessels → VUJ)
• "Bull's eye" in pelvis = phlebolith (benign venous calcification), not a stone

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4. MULTIPLE AIR FLUID LEVELS IN ABDOMEN

What to Say

"This is an erect abdominal X-ray showing multiple air-fluid levels with dilated loops of bowel in a step-ladder pattern, consistent with mechanical small bowel obstruction."

Key Differentials by Pattern

Distinguishing SBO vs LBO on X-ray

FAQ Viva Questions

Post-operative adhesions (60-70%) Others: Hernias (Richter's, femoral), Crohn's, malignancy

Carcinoma of the colon (most common), then diverticular disease, volvulus

Danger zone - risk of caecal perforation (Law of Laplace). Requires emergency decompression.

Obstruction: transition point present, gas absent distally (complete) Paralytic ileus: gas throughout (small bowel + large bowel + rectum), no transition point

Strangulation - closed loop obstruction → ischaemia → perforation

Tricks to Remember

• "3-6-9 Rule": Small bowel >3cm, Large bowel >6cm, Cecum >9cm = pathological
• Valvulae conniventes = cross ENTIRE bowel width = SMALL bowel (like a complete bridge)
• Haustra = cross PARTIAL width = LARGE bowel (like half a bridge)
• String of pearls sign = air bubbles trapped between valvulae = SBO

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5. RETROGRADE URETHROGRAPHY (RGU)

What to Say

"This is a retrograde urethrogram showing contrast introduced via urethral meatus outlining the urethra. There is a filling defect / narrowing / extravasation at [level], consistent with urethral stricture / injury."

Anatomy Quick Recall

• Anterior urethra = spongy (penile) + bulbar urethra (within bulbospongiosus)
• Posterior urethra = membranous (most vulnerable) + prostatic

When to Use

• Suspected urethral stricture (post-infection, trauma, instrumentation)
• Acute urethral injury (pelvic fracture)
• Pre-operatively before urethral reconstruction

Normal RGU Findings

• Smooth, tapering caliber
• No extravasation
• Posterior urethra fills when voiding (MCU needed for posterior)

FAQ Viva Questions

Historically: Gonococcal urethritis (long segment, bulbar) Now: Instrumentation/catheterization (iatrogenic) - shorter segment

Bulbo-membranous junction (posterior urethra - associated with pelvic fractures)

Triad: Blood at meatus + perineal hematoma (butterfly hematoma) + inability to void NEVER catheterize until urethra cleared!

RGU - for anterior urethra (stricture, trauma evaluation) MCU (Micturating cystourethrogram) - for posterior urethra, VUR, bladder neck

Tricks to Remember

• "Blood at meatus = STOP - do RGU first" - never blindly catheterize
• Butterfly hematoma = blood in Colles' fascia = bulbar urethral injury
• RGU performed with 30-45 degree oblique view for best visualization

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6. MICTURATING CYSTOURETHROGRAM (MCU / VCUG)

What to Say

"This is a micturating cystourethrogram showing the bladder filled with contrast and during voiding. There is reflux of contrast into the ureter bilaterally/unilaterally or posterior urethral valve filling consistent with [diagnosis]."

Main Indications

1. Vesicoureteric reflux (VUR) grading
2. Posterior urethral valves (PUV) in male children
3. Neurogenic bladder
4. Bladder diverticulum
5. Evaluation of posterior urethra (male)

VUR Grading (Mnemonic: "1-2-3-4-5 = Ureter-Pelvis-Blunting-Moderate-Severe")

FAQ Viva Questions

Male infant with poor urinary stream, distended bladder, failure to thrive MCU shows: "Spinning top" deformity of posterior urethra + bilateral VUR

Grade I-III: Conservative (antibiotic prophylaxis) Grade IV-V: Surgical (ureteric reimplantation - Cohen's/Leadbetter-Politano procedure) Endoscopic: STING/HIT procedure (sub-ureteric injection of Deflux)

DMSA scan shows cortical scarring = reflux nephropathy

Tricks to Remember

• MCU = best for posterior urethra and bladder
• VUR is commonest cause of chronic pyelonephritis in children
• Grade V = "polar bear paw" appearance (grotesquely dilated system)

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7. INTRAVENOUS UROGRAPHY (IVU / IVP)

What to Say

"This is an intravenous urogram. The plain film (KUB) shows [describe stones]. Post-contrast films show [nephrogram phase / pyelogram phase]. There is [delayed nephrogram / hydronephrosis / filling defect] on the right/left side consistent with [diagnosis]."

Phases of IVU

Classic Signs

• Rim sign: Thin rim of renal tissue = severe hydronephrosis
• Crescent sign: Thin crescent of contrast = partial obstruction
• Delayed dense nephrogram: Obstruction (contrast concentrated but can't drain)
• Goblet/wineglass sign: Ureteric filling defect = transitional cell carcinoma
• Filling defect in PCS: TCC, clot, papillary necrosis

FAQ Viva Questions

Allergy to iodine/contrast, renal failure (creatinine >1.5), severe dehydration, myeloma, metformin use (risk of lactic acidosis - stop 48 hours before)

CT-KUB (NCCT) - gold standard for urolithiasis (no contrast needed) CT urogram - for upper tract TCC evaluation

PUJ obstruction - dilated pelvis with abrupt cut-off at PUJ

Bilateral obstruction, acute tubular necrosis, bilateral renal artery stenosis, severe contrast allergy

Tricks to Remember

• IVU = functional AND morphological assessment (unlike USG which is only morphological)
• "The later the film, the more information about obstruction"
• Always take post-micturition film - shows residual urine and lower ureter
• Horseshoe kidney on IVU: calyces point medially, PUJ high, isthmus visible at L3-L4

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8. BARIUM SWALLOW - OESOPHAGUS

What to Say

"This is a barium swallow study showing opacification of the oesophagus. There is a [smooth/irregular/rat-tail] narrowing at the [level] with [mucosal pattern] consistent with [benign stricture / carcinoma oesophagus]."

Normal Oesophagus on Barium

• Smooth mucosal folds, 3-4 parallel columns
• No filling defects
• Cricopharyngeal impression at C5-6 (normal indentation)

Benign vs Malignant Narrowing

FAQ Viva Questions

Pharyngeal/Zenker's diverticulum, foreign body, web (Plummer-Vinson syndrome), leiomyoma

Pharyngeal pouch (Zenker's diverticulum) - false diverticulum, posterior, through Killian's dehiscence

• Rat-tail narrowing (irregular, shouldered filling defect)
• Mucosal destruction
• Shouldering sign = abrupt change from normal to narrowed = malignant

Middle 1/3 (50%) > Lower 1/3 (30%) > Upper 1/3 (20%) Squamous cell carcinoma in upper/middle; Adenocarcinoma in lower 1/3 (Barrett's related)

Tricks to Remember

• Rat tail = Carcinoma (irregular, abrupt, shelf-edge)
• Bird beak = Achalasia (smooth, symmetrical, gradual)
• Smooth cork-screw = Diffuse oesophageal spasm
• Barium swallow done with fluoroscopy - dynamic study (swallowing assessed)

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9. BARIUM SWALLOW IN ACHALASIA CARDIA

What to Say

"This is a barium swallow showing a markedly dilated oesophagus with a smooth, symmetrical tapering at the gastro-oesophageal junction producing a classic 'bird's beak' or 'rat-tail' appearance, consistent with achalasia cardia."

Classic Radiological Features

• Dilated sigmoid oesophagus (grossly dilated in late stage)
• Absent gastric air bubble (no gas passes into stomach)
• Bird's beak / rat-tail / pencil tip deformity at GEJ - smooth, tapered
• Air-fluid level in oesophagus on erect film
• Food residue in oesophagus (causes aspiration pneumonitis)

Pathophysiology (for viva depth)

• Loss of Auerbach's (myenteric) plexus ganglion cells
• Failure of LES relaxation + absent peristalsis
• Primary (idiopathic) vs Secondary (Chagas disease - Trypanosoma cruzi)

FAQ Viva Questions

Oesophageal manometry - shows:

1. Absent peristalsis in smooth muscle oesophagus
2. Incomplete/absent LES relaxation
3. Elevated resting LES pressure

Chicago Classification (HRM):

• Type I: Classic achalasia (no esophageal pressurization)
• Type II: Panesophageal pressurization (best prognosis with treatment)
• Type III: Spastic (premature contractions)

1. Heller's cardiomyotomy (laparoscopic) - gold standard surgical
2. POEM (Per-Oral Endoscopic Myotomy) - newest, least invasive
3. Pneumatic balloon dilatation - endoscopic, good but 30% need repeat
4. Botulinum toxin injection - temporary, for elderly/unfit

Type II achalasia

Tricks to Remember

• "Bird beak at bottom = Achalasia" (smooth, symmetric, at GEJ)
• "Rat tail going up = Ca oesophagus" (irregular, from below upward)
• Absent gastric bubble = pathognomonic hint of achalasia
• Aspiration pneumonia in right lower lobe = common complication

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10. BARIUM ENEMA

What to Say

"This is a barium enema study showing the large bowel filled with contrast. [Describe anatomy visible - cecum, ascending, transverse, descending, sigmoid]. There is a [filling defect / stricture / diverticulosis / irregular mucosa] at [site]."

Normal Anatomy on Barium Enema

• Cecum - right iliac fossa
• Haustra pattern throughout
• Rectum - smooth, no haustra
• Terminal ileum may be seen refluxing (TIIR = normal finding)

When to Use

• Suspected colonic lesion (but largely replaced by colonoscopy)
• Hirschsprung disease (water-soluble contrast enema)
• Assessment of fistulae, strictures

FAQ Viva Questions

"Apple core" lesion (annular carcinoma) = circumferential filling defect with mucosal destruction at the site

Transition zone from narrow aganglionic segment (distal) to dilated normal ganglionic segment (proximal) Delayed evacuation film (24-hour film) shows retained barium

Multiple outpouchings (diverticula) along sigmoid, may show spasm ("saw-tooth" mucosa)

Gastrografin (water-soluble, Meglumine diatrizoate) - NOT barium (barium peritonitis is lethal)

Tricks to Remember

• "Apple core" = circumferential Ca colon
• "Lead pipe" colon = ulcerative colitis (loss of haustra, shortened colon)
• Always use water-soluble contrast if perforation suspected
• Barium enema preceded by bowel prep (Fleet enema, sodium phosphate)

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11. FOREIGN BODY IN ABDOMEN

What to Say

"This is an X-ray abdomen/chest showing a radio-opaque foreign body in the [location] consistent with a [swallowed foreign body / ingested coin / surgical sponge / needle]."

Surgical Significance (Retained Surgical FB)

• Gossypiboma / Textiloma = retained surgical sponge
• Contains radiopaque marker thread - visible on X-ray
• Can cause: abscess, fistula, bowel obstruction (late presentation)

FAQ Viva Questions

Coin - most common, usually lodges at thoracic inlet (cricopharyngeus), or GEJ

• Oesophagus: Coin is in FRONTAL plane (face-on on PA film = round shape)
• Trachea: Coin is in SAGITTAL plane (edge-on = linear on PA film) Think: trachea has cartilage rings anteriorly = coin stands on edge

If impacted > 24h or causing symptoms: Endoscopic removal (rigid oesophagoscopy for sharp FB) Coins < 24h: may watch and repeat X-ray in 12-24 hours

Emergency! Causes pressure necrosis AND alkaline chemical injury within hours. Immediate endoscopic removal.

1. Cricopharyngeus (at C6) - most common
2. Aortic arch impression (T4)
3. Left main bronchus impression
4. Lower oesophageal sphincter
5. Ileocecal valve (if reaches intestine)

Tricks to Remember

• Coin in AP = oesophagus; Coin in lateral = trachea (opposite of what you'd think!)
• Sharp objects (bones, pins): upright films, admit, monitor passage
• Battery = Emergency (don't wait)

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12. SIGMOID / GASTRIC VOLVULUS

What to Say

Sigmoid Volvulus: "This is an erect/supine abdominal X-ray showing a markedly dilated loop of large bowel in the right upper quadrant arising from the pelvis, producing the classical 'coffee bean' / 'inverted U' sign, consistent with sigmoid volvulus."

Gastric Volvulus: "This is an X-ray/barium study showing two large air-fluid levels in the left upper quadrant / upward displacement of stomach consistent with gastric volvulus."

Sigmoid Volvulus - Classic Signs

FAQ Viva Questions

Sigmoid volvulus (high fiber diet + long sigmoid mesocolon in Indian population)

Long sigmoid mesocolon, high-fiber diet, chronic constipation, psychiatric/institutionalized patients

Endoscopic derotation (sigmoidoscopy + rectal tube insertion) - success in 70-90% Definitive: Hartmann's procedure or sigmoid colectomy (after optimization)

• Organo-axial (most common, rotates around long axis = greater curve goes anterior)
• Mesentero-axial (rotates around short axis)

1. Sudden severe epigastric pain
2. Unproductive retching
3. Inability to pass NG tube

"Coffee bean in LUQ" - ectopic cecum in left upper quadrant, appendix seen separately

Tricks to Remember

• "Sigmoid = coffee bean, LBO phenotype, points to RIGHT (liver) side"
• "Cecal volvulus = Coffee bean in LUQ (paradoxical position)"
• Borchardt's triad = Gastric volvulus (Borchardtl → Big pain, Blocking NG tube, dry Betch)
• Sigmoid volvulus: Psych ward patients + elderly constipated - classic history

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13. WORM IN INTESTINE (Ascariasis)

What to Say

"This is a plain abdominal X-ray / barium follow-through showing tubular filling defects within the intestinal lumen with central radiolucent line (representing gut of worm within gut), consistent with Ascaris lumbricoides infestation."

Classic Signs

• "Double line" or "triple line" sign on barium - barium in outer intestine + worm swallows barium itself (barium in worm's gut = central line = "train track" sign)
• Whirlpool mass - bolus of worms
• Mass in RIF - bolus of worms can mimic appendicular mass

FAQ Viva Questions

1. Intestinal obstruction (bolus obstruction - most common surgical complication)
2. Biliary ascariasis (worm enters CBD via ampulla - biliary colic, cholangitis)
3. Appendicitis, perforation, liver abscess

Ascaris lumbricoides - worm ingests barium = barium within worm (central line) + barium around worm

Mebendazole 100mg BD x 3 days OR Albendazole 400mg single dose Biliary ascariasis: endoscopic extraction (ERCP) + antihelminthics Obstruction: mostly resolves with conservative (NG tube, IV fluids + antihelminthics) - surgery if strangulation

Ascaris (MC helminth surgical emergency in India/South Asia)

Tricks to Remember

• "Worm eats barium = railway track sign" (unique to Ascaris)
• Largest intestinal nematode = Ascaris lumbricoides (15-35 cm)
• Surgical rule: "Don't rush to surgery for Ascaris obstruction" - most resolve conservatively

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14. FOREIGN BODY IN GI TRACT

Additional GI-Specific Points

FAQ Viva Questions

1. Button batteries (chemical + pressure necrosis - emergency)
2. Sharp objects (needles, fishbones, bones) in oesophagus
3. Magnets (multiple magnets cause bowel wall necrosis + fistula)
4. Any FB causing symptoms (dysphagia, pain, bleeding)

Most common site: Palatine tonsil > Tongue base > Vallecula > Pyriform fossa > Cricopharyngeus

CT neck and chest - most fishbones, chicken bones are RADIO-LUCENT Also: endoscopy

May not pass pylorus - consider endoscopic retrieval

Tricks to Remember

• Most ingested FBs (80%) pass spontaneously
• "Penny in the esophagus - scope it; Penny in the stomach - watch it"
• Multiple magnets in different bowel loops = disaster (attract through bowel wall)

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15. BARIUM ENEMA IN CARCINOMA COLON

What to Say

"This is a double contrast barium enema showing a classic 'apple core' or 'napkin ring' filling defect with mucosal destruction at the [splenic flexure/sigmoid/descending colon] consistent with carcinoma of the colon."

Apple Core Sign

• Circumferential (annular) carcinoma causes a shouldered filling defect
• Mucosa is destroyed within the lesion
• Proximal bowel may be dilated (partial/complete LBO)
• "Shelf edges" = abrupt transition from normal to tumour

FAQ Viva Questions

Rectum > Sigmoid > Descending colon > Hepatic flexure Mnemonic: "Rectal-Sigmoid is most Reliable Site" (RS most common)

Adenocarcinoma (>95%)

Stage	Description	5-yr Survival
A	Mucosa/submucosa only, not through muscularis	>90%
B	Through muscularis propria, no nodes	70-80%
C1	Nodes positive, apex not involved	35-40%
C2	Apical node involved	25%
D (Turnbull/modified)	Distant metastasis	<5%

Not for diagnosis - used for monitoring recurrence after resection

Anterior resection (sigmoid/upper rectum) Lower rectum: Hartmann's (emergency) or LAR (elective) Very low rectum: Abdominoperineal resection (Miles' operation)

Tricks to Remember

• "Apple core = colon cancer until proven otherwise"
• Carcinoma right colon: iron deficiency anemia, mass, weight loss (occult bleeding, liquid stool masks it)
• Carcinoma left colon: obstruction symptoms (altered bowel habit, blood in stool, pencil stools)
• "Right colon = anemia; Left colon = obstruction"

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16. ULCERATIVE COLITIS (on Barium Enema)

What to Say

"This is a double-contrast barium enema showing a continuous, diffuse loss of haustra affecting the entire colon with a 'lead pipe' appearance and fine mucosal granularity, consistent with ulcerative colitis."

Classic Radiological Features

UC vs Crohn's on Barium

FAQ Viva Questions

Crohn's disease - narrow string-like lumen in terminal ileum due to spasm or fibrotic stricture on barium follow-through

1. Toxic megacolon (transverse colon >6 cm - emergency colectomy)
2. Carcinoma colon (risk increases after 10 years, pancolitis)

Toxic megacolon, perforation, massive hemorrhage, failure of medical therapy

Primary Sclerosing Cholangitis (PSC) - correlates with extent but not activity Also: uveitis, erythema nodosum, pyoderma gangrenosum, ankylosing spondylitis

Proctocolectomy + Ileal Pouch Anal Anastomosis (IPAA) = J-pouch - gold standard

Tricks to Remember

• UC = Continuous + Rectum always (like UC-tus = United Continuous)
• Crohn's = Skip + Can be Anywhere (like C for Crohn's = Can Skip)
• Lead pipe = UC (rigid, tubular, no haustra = lost architecture)
• Toxic megacolon: transverse >6cm = emergency

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17. BARIUM SWALLOW IN CARCINOMA STOMACH

What to Say

"This is a barium meal / upper GI series showing irregular filling defect with mucosal destruction in the [fundus/body/antrum] with rigidity and narrowing, consistent with carcinoma stomach."

Classic Signs

Benign vs Malignant Gastric Ulcer on Barium

FAQ Viva Questions

Adenocarcinoma (95%) Others: GIST, lymphoma, carcinoid

• Intestinal type: Well-differentiated, associated with H. pylori, good prognosis, distal
• Diffuse type: Poorly differentiated, signet ring cells, young patients, linitis plastica

Left supraclavicular node = Troisier's sign = metastatic gastric cancer (via thoracic duct)

Umbilical metastasis from GI malignancy (mainly gastric/colonic)

Ovarian metastasis from gastric cancer (signet ring cells, bilateral)

Japan: 5-yr survival ~70% (early detection, mass screening) India/West: <20-30% (late presentation)

Tricks to Remember

• "Hampton's line = Benign" (Hampton = Harmless = Benign)
• Linitis plastica = Leather bottle (diffuse, rigid, non-distensible)
• Virchow's node = Left supraclavicular = "V for Victory = Virchow"
• Krukenberg = ovary = trans-peritoneal spread (from stomach, colon, appendix)

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18. NCCT BRAIN

What to Say

"This is a non-contrast CT scan of the brain (NCCT head). [Describe: Windows used - brain vs bone]. There is a [hyperdense / hypodense / mixed density] [crescentic / biconvex / ring-enhancing] lesion at [location], consistent with [SDH / EDH / ICH / abscess / tumor]."

CT Density Quick Reference

Common Surgical Pathologies on NCCT Brain

FAQ Viva Questions

1. Hypertension (widened pulse pressure)
2. Bradycardia
3. Irregular breathing (Cheyne-Stokes)

Effacement of sulci and cisterns, midline shift, loss of grey-white differentiation, "slit ventricles" or hydrocephalus depending on cause

EDH - patient with lucid interval then rapid deterioration (MC cause: temporal EDH from middle meningeal artery, associated with pterion fracture)

Tricks to Remember

• "Bi-Convex = EDH; Cres-cent = SDH"
• Pterion = thinnest skull bone = fracture → middle meningeal artery tear → EDH
• Lucid interval = EDH until proven otherwise
• SAH = Thunderclap headache + blood in basal cisterns on NCCT

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19. CECT ABDOMEN

What to Say

"This is a contrast-enhanced CT scan of the abdomen (CECT abdomen) taken in the [arterial / portal venous / delayed] phase. There is [describe findings - organ, density, enhancement pattern, surrounding fat stranding, lymph nodes, ascites] consistent with [diagnosis]."

Phases of CECT Abdomen

Common Surgical Findings on CECT Abdomen

FAQ Viva Questions

Combines CT grade (A-E) + Necrosis score CTSI = CT Grade (0-4) + Necrosis (0-6) = Max 10 Score 0-3: Low severity; 4-6: Moderate; 7-10: Severe (30% mortality)

>6mm with other features = appendicitis (specificity high when combined with fat stranding)

• HCC
• Hepatic hemangioma (peripheral nodular enhancement → centripetal fill-in)
• FNH (central scar)
• Adenoma
• Hypervascular metastases (RCC, NET, choriocarcinoma, thyroid Ca)

Liver has dual blood supply: hepatic artery + portal vein Tumors (HCC) fed by hepatic artery = enhance in arterial phase Normal liver = portal venous = HCC becomes hypodense (washout) in portal phase

FAST: rapid bedside (Morison's pouch, splenorenal, pelvic, pericardial) CECT: gold standard for stable trauma patients - grades organ injuries

Tricks to Remember

• "Arterial phase = Arteries + Hypervascular tumors"
• "Portal phase = Parenchyma + Most pathology"
• HCC hallmark: "In bright, then washed out" (arterial hyper, portal washout)
• Pancreatitis grading: "Balthazar A to E" with necrosis = CTSI

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MASTER MNEMONIC SUMMARY TABLE

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RAPID-FIRE VIVA TRICKS

The "MUST KNOW" List for Finals

1. Bird beak = Achalasia | Rat tail = Ca oesophagus | Cork-screw = DES
2. Apple core = Colon Ca | Lead pipe = UC | String sign of Kantor = Crohn's
3. Coffee bean = Sigmoid volvulus | Borchardt's triad = Gastric volvulus
4. Biconvex = EDH | Crescent = SDH | Lucid interval = EDH (ptérion fracture)
5. Rigler's sign = Pneumoperitoneum (double wall sign on supine)
6. Railway track sign = Ascaris (worm ingests barium)
7. Hampton's line = Benign ulcer | Heaped margin = Malignant
8. Linitis plastica = Leather bottle = Ca stomach (diffuse)
9. 3-6-9 rule: SB 3cm, LB 6cm, Cecum 9cm = danger
10. Valvulae conniventes cross FULL width = Small bowel
11. Haustra cross PARTIAL width = Large bowel
12. Virchow's node = Left supraclavicular = Gastric Ca (Troisier's sign)
13. Spinning top deformity = Posterior urethral valves (MCU)
14. HCC on CT = In bright (arterial) then washed out (portal)
15. CTSI (Balthazar) = Grade (A-E) + Necrosis % = Pancreatitis severity

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