3 Sturge–Weber Syndrome

Remi Nader

Fig. 3.1 (A,B) Computed tomography scan without contrast, brain windows, and bone windows (C,D), showing lesion in the left hemisphere.

Clinical Presentation

A 31-year-old man had a grand mal seizure episode at home while eating.

He is brought to the emergency room at an outside hospital, where he obtains a computed tomography (CT) scan, which is read as “suspicious subarachnoid hemorrhage.” He is then transferred to your hospital for further care. On arrival, the patient was in status epilepticus, intubated, and receiving diazepam and phenytoin.

Initial CT scan is shown in Fig. 3.1.
The family arrives shortly after patient is stabilized and further history is obtained.
The patient is known to have a seizure disorder, and the first seizure was 6 years ago. He also has a longstanding expressive speech deficit. He has had a left-sided hemiparesis for the past 6 years with joint contractures.
The family was told by his primary care physician that he has a “brain condition” for which they did not know the name.
He recovers back to his baseline neurologic status the next day.

Fig. 3.2 (A,B) Magnetic resonance images with contrast, (C) magnetic resonance angiography coronal, and (D) axial reconstructed images showing abnormality in the left hemisphere.

Questions

Interpret the initial computed tomography (CT) scan.

What is the differential diagnosis?

What is the most likely diagnosis based on the history given by the family?

What other findings do you expect on general and neurologic examination?

How do you manage status epilepticus?

What other investigations would you like to obtain?

CT with contrast, magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) are obtained and shown in Fig. 3.2. Interpret the studies.
What is the treatment of this condition?
Describe some surgical options of managing seizures for this condition.
What are the indications for hemispherectomy?

Answers

Interpret the initial CT.

On brain windows: Hyperdensities are seen involving the left hemisphere only. These findings could represent acute blood, calcifications, tumor cells, or an abnormal vascular pattern (which is the most likely possibility).
On bone windows: Calcifications are seen involving the left temporal and parietal region. The calcifications are most likely cortical in nature and are not representing acute hemorrhage.
There is mild mass effect with a mild amount of left-to-right shift.

What is the differential diagnosis?

Congenital: neurocutaneous disorder (Sturge– Weber syndrome)

Infectious: encephalitis (viral, bacterial), purulent meningitis

Traumatic: contusion, subarachnoid hemorrhage

Tumor: gliomatosis, metastatic disease, lymphoma

Inflammatory: progressive multifocal leukoencephalopathy, viral encephalitis, ossifying meningoencephalopathy

Vascular: arteriovenous malformation, venous angiomas 1
What is the most likely diagnosis based on the history given by the family?
- Sturge–Weber syndrome¹
What other findings do you expect on general and neurologic examination?
- Port-wine stain (facial angiomas): usually unilateral involvement of the skin supplied by the ophthalmic division of the trigeminal nerve.^2,3 Rarely can be bilateral.
- Leptomeningeal angiomas: usually occipital and posterior parietal
- Seizures (by age 3 years: 75–90%).^2,3
- Hemiparesis (25–60%) and hemiatrophy (possibly from chronic cerebral hypoxia)¹
- Mental retardation or learning disability (50–75%)²
- Glaucoma (30–70%) and vascular eye abnormalities
- Hemianopsia (40–45%)
- Vascular headaches (40–60%)²
- Developmental delay and mental retardation (50–75%)
- Moya moya disease
- Arteriovenous malformations of the lung and liver
How do you manage status epilepticus?
- Intravenous (i.v.) glucose 50% 50 mL, i.v. thiamine 100 mg (folate/multivitamin), intubate, i.v. access
- Laboratory: complete blood count (CBC), electrolytes, serum glucose, serum calcium levels, arterial blood gas
- Neurologic examination
- Pharmacologic treatment (as follows, in order given):
  - – Lorazepam 1–2 mg every 5 minutes, up to 9 mg (0.1 mg/kg) or diazepam 5 mg every 5 minutes, up to 20 mg (0.2 mg/kg)
  - – Phenytoin – loading dose 20 mg/kg
  - – Phenobarbital – drip load 20 mg/kg
  - – Pentobarbital – drip 20 mg/kg if seizure did not arrest in 30 minutes
- General anesthesia^4,5
What other investigations would you like to obtain?
- CT of the brain with contrast
- MRI/magnetic resonance angiography (MRA) of the brain
- 4-vessel cerebral angiogram
- Electroencephalogram
- Laboratory tests: CBC, electrolytes, prothrombin time, partial thromboplastin time, type and screen³
CT with contrast, MRI, and MRA are obtained and described below. Interpret the studies.
- CT with contrast: There is extensive serpentine leptomeningeal enhancement involving the left temporal and parietal region.
- MRI: Extensive cortical parenchymal calcification in the left cerebral hemisphere predominantly in the parietal and occipital region with some extension into the frontal and temporal lobes is demonstrated with decreased signal. Postcontrast examination again demonstrated serpentine enhancement of almost the entire cerebral hemisphere with enhancement also within the brain parenchyma. Minimal mass effect with slight midline shift is seen.
- MRA: Extensive abnormal cerebral arteries are demonstrated in the left cerebral hemisphere consistent with leptomeningeal venous abnormalities.
What is the treatment of this condition?
- Aggressive treatment of seizures with antiepileptics (carbamazepine is the usual first-line medication)
- Stroke prevention (aspirin, good hydration, etc.)
- Aggressive treatment of fever
- Treat iron deficiency with anemia vitamin supplementation
- Flu shot
- Treat headaches symptomatically
Describe some surgical options of managing seizures for this condition.
- Hemispherectomy (functional or anatomic)
- Corpus callosum interruption
- Localized cortical resection⁶
What are the indications for hemispherectomy?
- Indications: intractable epilepsy with unilateral hemisphere damage, congenital hemiplegia, chronic encephalitis, hemimegalencephaly, or Sturge– Weber syndrome
- It is performed only on patients who have a dense hemianopsia and are already hemiplegic with no fine motor activity on the affected side.
- The acute surgical risk is that some crude movement or sensation on the opposite side of the body would be adversely affected.
- Chronic risks include superficial cerebral hemosiderosis.^7,8