TOACS FCPS Station · Skull X‑ray: Sturge‑Weber Syndrome

📷 Skull X‑ray (AP & Lateral views)

Skull X-ray showing tram-track calcifications in Sturge-Weber syndrome

Figure 1 · Skull radiographs · Sturge‑Weber Syndrome – Tram‑Track Calcifications

🔍 Key radiographic features:

✓ Tram‑track calcifications – bilateral or unilateral gyriform cortical calcifications
✓ Parallel curvilinear densities – follow the gyral pattern of the brain
✓ Unilateral predominance – typically ipsilateral to facial port‑wine stain
✓ Thickened skull – may be seen overlying the affected hemisphere
✓ Choroid plexus enlargement – may be visible in some cases

📋 Clinical scenario (examiner prompt)

A 5‑year‑old child with a known unilateral facial port‑wine stain involving the V1 dermatome presents with focal seizures and contralateral hemiparesis. The child has a history of glaucoma in the same eye and developmental delay. Skull X‑ray (AP & lateral views) is shown.

Port‑wine stain Tram‑track calcifications Focal seizures Glaucoma

🧑‍⚕️ Examiner tasks · TOACS

1. Identify the diagnosis from the skull X‑ray and clinical context.

2. Describe the X‑ray findings (tram‑track calcifications, gyriform pattern).

3. Explain the pathophysiology (leptomeningeal angioma, GNAQ mutation).

4. Discuss the clinical triad and management (seizures, glaucoma, neurocutaneous).

⚠️ Key concept: Tram‑track (gyriform) calcifications on skull X‑ray are a classic finding in Sturge‑Weber syndrome. They represent cortical calcification underlying the leptomeningeal angioma. The clinical triad includes: facial port‑wine stain (V1 dermatome), ipsilateral leptomeningeal angioma, and glaucoma. The condition is caused by a somatic GNAQ mutation.

🎯 Expected answers (for examiners)

• Diagnosis: Sturge‑Weber syndrome
• X‑ray findings: Tram‑track (gyriform) calcifications, unilateral predominance
• Pathophysiology: Somatic GNAQ mutation → leptomeningeal angioma → cortical calcification, cerebral atrophy
• Clinical triad: Facial port‑wine stain (V1), leptomeningeal angioma, glaucoma
• Management: AEDs (seizures), ophthalmology (glaucoma), low‑dose aspirin (stroke‑like episodes), hemispherectomy (refractory seizures)

⚡ Quick FCPS‑style MCQ

Tram‑track calcifications on skull X‑ray in a child with a facial port‑wine stain are most consistent with:

A. Neurofibromatosis type 1 B. Sturge‑Weber syndrome C. Tuberous sclerosis D. Ataxia‑telangiectasia

Feature	Sturge‑Weber Syndrome
Facial stain	V1 (ophthalmic) ± V2, unilateral
Brain	Leptomeningeal angioma (pial enhancement)
Calcifications	Tram‑track (gyriform), CT/X‑ray
Eye	Glaucoma (ipsilateral)
Genetics	GNAQ (somatic mosaic)

🩻 TOACS FCPS Station · Skull X‑ray: Sturge‑Weber Syndrome

📷 Skull X‑ray (AP & Lateral views)

🧑‍⚕️ Examiner tasks · TOACS

📌 Topic summary ·