27 Diffuse Cerebral Angiomatosis

Diffuse Cerebral Angiomatosis

Clinical Presentation

A 30-year-old woman was admitted to our department following a generalized epileptic seizure. After recovering, she reported a several years’ history of chronic throbbing headaches that were frequently accompanied by nausea and vomiting. More recently, she had developed left-sided hypoacusis, gradually worsening bilateral pulsatile tinnitus, impaired visual acuity, and recurrent transient left-sided hemiparesis, each of which lasted up to 3 hours. Her medical history had been unremarkable until she was 13 years old, at which stage a periorbital bruit, left-sided retinal edema, and retinal hemorrhages were incidentally discovered. Cranial CT performed at this time was reported to be normal. She remained asymptomatic until the age of 22, when a right central retinal venous thrombosis led to marked visual impairment in addition to a focal seizure with a left-sided hemisyndrome. Subsequently she developed symptomatic focal epilepsy and received carbamazepine as medication. The frequency of seizures increased after the birth of her daughter and changed to predominantly generalized epilepsy.

Physical examination on admission revealed bilateral periorbital pulsatile bruits, a reduced right-sided visual acuity, a bilateral retinal angiomatosis, a left-sided inner ear deafness, and a mild left-sided sensorimotor hemiparesis.

Initial Neuroradiologic Findings

Cerebral MRI on the day of admission did not reveal any ischemic lesions but did show multiple pathologic vessel signals with a right-sided predominance as well as right hemispheric brain atrophy. Intracranial contrast-enhanced MR angiography (ce-MRA) showed multiple dilated, pathologic vessels with right-sided predominance (Fig. B27.1 and Fig. B27.2).

Suspected Diagnosis

Bihemispheric arteriovenous malformation (AVM).

Questions to Answer by Ultrasound Techniques

Which were the arterial feeders and venous drainage vessels?
Can a multimodal assessment be made of cerebral hemodynamics including the measurement of global cerebral blood flow (gCBF), global cerebral circulation time (gCCT), and global cerebral blood volume (gCBV)?

Initial Neurosonologic Findings

Extracranial Duplex Sonography

B-mode ultrasound revealed no atherosclerotic vascular changes. Doppler spectrum analysis showed normal and symmetric flow signals, but velocities were generally increased in all extracranial arteries and also in the internal jugular veins (IJVs) (Figs. B27.3–B27.8).

Transcranial Duplex Sonography

Transcranial color-coded sonography (TCCS) showed increased flow velocities (between 100 cm/s and 250 cm/s systolic flow), low pulsatility indices (<0.6), and moderately turbulent flow patterns in all basal cerebral arteries (Figs. B27.9–B27.14). In addition, flow velocities were raised in the detectable cerebral venous vessels (not shown).

Multimodal Assessment (gCBF, gCCT, and gCBV)

The gCBF, assessed as the sum of blood volume flow in both internal carotid arteries (ICAs) and vertebral arteries (VAs) was 2,620 mL/min, which is approximately three times higher than in healthy individuals. The gCCT was determined as the time delay between the arrival of the contrast bolus at the extracranial ICA and its exit at the extracranial IJV following intravenous injection of Levovist contrast bolus into an antecubital vein. In our patient, the gCCT was significantly shortened (2.9 seconds; reference value 7 seconds; Fig. B27.15). The calculated ultrasound-derived gCBV (gCBF × gCCT) was increased (126 mL; reference value 80 mL) (see also Chapter 3, “Parameters of Cerebral Hemodynamics”).

Conclusion

Generalized increase of blood flow velocities and gCBF, reduction of gCCT, and increase of ultrasound-determined gCBV suggestive of marked hyperemia, consistent with a diffuse AVM on both hemispheres.

Conventional Angiography

Digital subtraction angiography (DSA) was performed to further analyze AVM, feeding arteries, and draining patterns, and to evaluate endovascular therapeutic options. A diffuse, superficial cortical angiomatosis was seen on both sides comprising numerous arteriovenous shunts leading to early venous filling of the markedly dilated superficial and deep cerebral veins (Fig. B27.16 and Fig. B27.17).

Clinical Course

The character of the malformation, consisting of a diffuse cortical angiomatosis without a classic AVM nidus and an additional retinal angiomatosis, did not allow any interventional therapy. The malformation was considered to be the most likely cause of the patient’s signs of increased intracranial pressure (headaches, nausea) and epilepsy as well as of the mild left-sided hemiparesis. The hemiparesis was either a recurrent Todd paresis or a result of transient hemodynamic steal phenomena, caused by right-sided accentuation of the malformation and the subsequent right-sided frontoparietal brain atrophy.

Fig. B27.1 MR T2-weighted image, axial plane. Numerous flow-void signals with a right-sided predominance as a correlate of pathologic arterial and venous vessels. Note the mild right-sided frontoparietal cortical atrophy. (Reproduced from Schreiber et al. Diffuse cerebral angiomatosis. Neurology 2003;60:1216–1218, with permission of the American Academy of Neurology as administered by Wolters Kluwer.)

The anticonvulsant treatment was optimized and additional symptomatic treatment with analgesics led to some reduction in headaches, nausea, and vomiting. However, the patient continued to have mild hemiparesis and epilepsy. It seems that the extent of the malformation had progressed from age 13 but remained stable over the last year of follow-up as control MRI and MRA did not suggest any remarkable changes in the angiomatosis.

Final Diagnosis

Bilateral cortical and retinal angiomatosis. A rare undefined neurocutaneous syndrome was considered.

Fig. B27.2 Intracranial contrast-enhanced 3D MRA, lateral oblique maximal intensity projection (MIP). Note multiple dilated arterial and venous vessels.