First and second year — the floor first, then every step
Measure the haematoma and its mass effect, then find the cause: its location (deep → hypertensive; lobar in the elderly → amyloid), the spot sign on CTA, and the signs of an underlying lesion or venous thrombosis.
Orient first
Deep haemorrhage (basal ganglia, thalamus, pons, cerebellum) in a hypertensive patient is usually hypertensive; lobar haemorrhage in an older patient raises cerebral amyloid angiopathy.
A young patient, an atypical location, or haemorrhage with more oedema than expected needs a search for a vascular malformation, tumour or venous thrombosis.
Haematoma expansion happens in the first hours; the CTA spot sign predicts it.
Acquire the study
Non-contrast CT on a brain window; CTA of the head (and a delayed phase if the protocol includes it).
The manoeuvre
Volume by ABC/2 (cm → mL); location; intraventricular extension; hydrocephalus; midline shift at the septum pellucidum.
Shape and density: irregular margins, heterogeneous density, fluid levels (anticoagulation) and the blend and black-hole signs (expansion risk).
CTA: spot sign (an enhancing focus within the haematoma), aneurysm, arteriovenous malformation, venous sinus filling.
What confirms it
An acute intraparenchymal haematoma, with a cause proven or a pattern that fits one.
What licenses you to exclude it
A negative CTA in the acute phase does not exclude a small malformation compressed by the haematoma — follow-up imaging.
The classic misread
Calling haemorrhage in a tumour "hypertensive" — look for disproportionate oedema and enhancement.
Reference values
Each value carries the caveat that keeps it from being misused. Normal limits and diagnostic criteria are kept apart on purpose: a disease cut-off read as a normal range is the more dangerous mistake.
Diagnostic criteria
Intracerebral haemorrhage · Haematoma volume by ABC/2
volume in cm³ approximated as A × B × C ÷ 2; 30 cm³ is a widely used severity and decision inflection
A = largest axial diameter of the haematoma; B = the diameter perpendicular to A on the same slice; C = the craniocaudal extent (number of slices × slice thickness). All in centimetres.
ABC/2 systematically over-estimates irregular and anticoagulation-related haematomas — say "approximately". Location changes the meaning of any volume: 10 cm³ in the posterior fossa is a different emergency from 10 cm³ in the frontal lobe.
CT
Intracerebral haemorrhage (score) · ICH score inputs — how to report them
a named score: GCS, age, infratentorial origin, IVH, and volume (ABC/2, already registered) — report the inputs; the arithmetic is the clinician's
Volume by ABC/2 is one input. Location (posterior fossa) changes the meaning of any volume, as the volume entry already says.
CT
See it on real cases
Direct links to Radiopaedia — the reference article and worked cases with their images. Each opens on Radiopaedia.