MR Venogram Head

Superior sagittal, transverse and sigmoid sinuses, straight sinus, deep venous system, and jugular bulbs, with whole-brain parenchymal sequences.

Typical, not policy

Timings, volumes and delays here are representative values drawn from published guidance. Scanner generation, injector, cardiac output and local preference all move them. Confirm against your department's own protocol before you rely on a number.

When to use it

Suspected cerebral venous sinus thrombosis, particularly with headache plus seizure, focal deficit or papilloedema.
Peripartum or postpartum headache with red flags.
Idiopathic intracranial hypertension, where transverse sinus stenosis is being assessed.
Unexplained venous-pattern parenchymal haemorrhage or infarction on a previous study.
Follow-up of known sinus thrombosis to assess recanalisation.

Technique

Two-dimensional time-of-flight venography is quick and widely available; three-dimensional phase contrast with an appropriate velocity encoding is often preferred for image quality and is less prone to T1-bright thrombus artefact.
Contrast-enhanced venography, static or dynamic, has the highest reported accuracy and is the usual problem-solver when flow-based venography is equivocal.
Parenchymal sequences including susceptibility-weighted imaging and DWI are integral: the thrombus itself is often visible directly.
Sources genuinely differ on the preferred first-line technique; phase contrast, time-of-flight and contrast-enhanced approaches all have current advocates.

Where it goes wrong

In-plane flow saturation in the transverse sinus on time-of-flight, the classic false-positive for thrombosis.
Subacute thrombus with intrinsic T1 high signal appearing as flow on time-of-flight projections — the opposite error.
Normal anatomical variation, especially a hypoplastic transverse sinus, read as occlusion when the parenchymal sequences and the sinus calibre have not been checked.
Reading projections without source images, which hides isolated cortical vein thrombosis entirely.
Requesting venography alone without brain sequences.

Clinical questions that reach this study

Suspected cerebral venous sinus thrombosis

Contrast

NoneGadolinium, intravenous

Where a contrast-enhanced venogram is used, a macrocyclic gadolinium agent at a typical single dose of about 0.1 mmol/kg, given at roughly 2-3 mL/s with a 20-30 mL saline chaser; a static post-contrast 3D T1 dataset is often added.

Phase-contrast and time-of-flight venography require no contrast. Contrast-enhanced venography is generally the most accurate but is not always necessary.
Venous timing, not arterial: a dynamic contrast-enhanced venogram is acquired at roughly 30-60 s from injection, or the sinuses are imaged on a steady-state post-contrast 3D T1 after about 1-2 minutes when the intravascular concentration has equalised. Running an arterial-timed sequence and calling it a venogram is a timing error, not an agent error.

Acquisition

Breathing: Free breathing.
Preparation: Request the brain sequences with it — venography in isolation misses the parenchymal changes that confirm or refute the diagnosis. Note pregnancy or postpartum status, which changes both pre-test probability and contrast decisions.

Safety checks this protocol carries

Derived from the contrast agent and phases above, not authored here — which is why they cannot drift apart from what the protocol actually does.

MR safety screening for implants and foreign bodies· radiographer at scan