Abdominal X-ray

Chest radiographs are phenomenal in terms of how much information they can provide given how simple and easy they are to perform. Abdominal films are also useful, but less commonly used as there are fewer indications for ordering them, and they don’t give the same wealth of information that a chest film can. Nevertheless, it’s essential that you can look at one without panicking, and get a rough idea about what’s going on inside that patient of yours.

Indications: “Gasses, masses, bones and stones”

  • Obstructed bowel
  • Perforated bowel
  • Bowel Ischaemia
  • Blunt or perforating abdominal injury
  • Intussusception
  • Foreign bodies
  • Suspected abdominal mass
  • Acute and chronic pancreatitis
  • Toxic megacolon


  • AP Supine
  • AP erect
  • Lateral decubitus
  • Supine lateral
  • KUB

Step 1: The basics

  • Patient Identity
    • right patient
      • name
      • date of birth
      • hospital number
        • always always always check all three – statistically the probability of two patients in the hospital having the same name and date of birth is scarily high…
    • right time
      • are you looking at a previous scan or the most recent
    • right view
      • is it the same as the one you ordered?
      • is it adequately exposed?
      • can you see the whole abdomen


Step 2: Gasses 3,6,9

  • Small bowel
    • Look for valvulae conniventes – or rings that distinguish small bowel from large
    • Small bowel shouldn’t be more than about 3 cm in diameter
  • Large bowel
    • Look for haustra – lines only go part way across the large bowel
    • The retroperitoneal parts are easier to find as they’re relatively constant in their location:
      • ascending
      • descending
      • rectum
    • Large bowel shouldn’t be more than 6 cm in diameter
    • The caecum shouldn’t exceed 9 cm
  • Walls
    • gas in the wall of bowel suggests ischaemic colitis
  • Air-Fluid levels
    • more than four or five visible fluid levels, great than 2.5 cm long is abnormal and may suggest:
      • gastroenteritis
      • ischaemia
      • obstruction
      • ileus
  • Peritoneum
    • Rigler’s sign (double wall) is a sign of intraperitoneal gas, and may reflect perforation or penetrating trauma
    • air may be seen under the diaphragm
  • Soft tissues
    • surgical emphysema may be visible especially after trauma

Step 3: Masses

  • Solid organs
    • Liver
      • Right upper quadrant
      • Grey
      • Breast tissue may overlie the upper aspect
      • May have cholescystectomy clips present
    • Spleen
      • Left upper quadrant
    • Kidneys
      • T12-L3
      • Right lower than left due to liver
    • Bladder
  • Psoas muscles
    • bulging may indicate a retroperitoneal pathology
  • Vessels
    • Calcifications may indicate an aortic aneurysm

Step 4: Bones

  • Ribs
  • Spine
  • Sacrum
  • Pelvis
    • Check all of these for:
      • fractures
      • degeneration
      • metastasis
      • cysts


Step 5: Stones

  • Stones should be looked for in the:
    • Kidneys
    • Ureters
      • follow the tips of the lumbar transverse processes down to the sacroiliac joint
      • The ischial spines mark where the ureters enter the bladder
    • Bladder
    • Gallbladder
    • Pancreas (calcification)



  • Piercings may look like foreign bodies
  • Not all calcification of soft tissues is clinically important


Hope this helps!









Headache differential

“Doctor I have a headache – am I going to die?”

“Well… eventually…”

As a doctor you have to try and give useful answers to fairly important questions, like, better than this.


Differential diagnoses are one of the most useful tools when it comes to diagnosing symptoms and it’s important to ensure you’ve thought of as many of the potential causes as possible. Here’s a weird way to remember the key causes of a headache in an emergency situation.

Typical Day in A&E

You are on duty in the emergency department and you’re feeling incredibly tense, as someone has just fired off a cluster grenade somewhere in the hospital. You’ve just been called in to see a patient who has a very bad headache, who says he has a history of migraines

As you enter the room, you notice he’s holding a cricket bat and smoking a huge joint. Next to him a washing machine is spinning out of control, pouring smoke all over the room.

You notice a weird tingling stiffness in your neck, when suddenly his head catches fire.

The man stands up and says “To Be Honest mate I’m just gonna go home”, but his head begins to expand and he starts grinding his jaw

You don’t see what happens next because you go blind and pass out.

  • Tension headache
  • Cluster headache
  • Migraine
  • Subarachnoid (feels like being hit with a bat)
  • Drugs
  • CO poisoning 
  • Meningitis
  • Encephalitis
  • TBH – Tumour, TB, Haematoma
  • Temporal arteritis
  • Glaucoma

Step 1: Take a history


  • First and worst headache ever
  • Sudden onset and really bad
  • Unilateral with eye pain
  • Worse on coughing
  • Scalp tenderness
  • Decrease in GCS

– Any trauma?

– Any neck pain?

– Any fever?

– Any loss of consciousness?

– Any decrease in consciousness?

– Any warning signs?

– Any fitting/biting of tongue?

– Any other medical conditions?

– Any changes in vision?

– Any drugs?

– Sudden or gradual onset?

– How severe?

Two crucial questions:

– “Have you been away?”

– “Could you be pregnant?”

Step 2: Do a neuro exam

Step 3: Look in their eyes

Step 4: Get thinking


No signs on examination:

Tension headache

– Migraine

– Cluster

– Post-trauma

– Drugs – particularly nitrates and calcium channel blockers

– CO poisoning

Signs of meningism:

– Meningitis

– Subarachnoid haemorrhage

Decreased consciousness:

– Encephalitis

– Meningitis

– Stroke

– Cerebral abscess

– Subarachnoid haemorrage

– Tumour

– Haematoma

– TB meningitis


– Tumour

– Malignant hypertension

– Benign intracranial hypertension

– CNS infection of >2weeks

Painful jaw/temple:

– Temporal arteritis

Changes in vision:

– Glaucoma


– Paget’s disease

– Sinusitis

– Altitude sickness

– Cervical spondylosis

– Venous sinus occlusion

– Vertebral artery dissection

All of the above information is from the Oxford Handbook of Clinical Medicine 7th Edition