By systematically reviewing the literature, we have found that there is very little information about the frequency and clinical course of arteriovenous malformations (AVMs) of the brain in adults because the methods of most studies have been flawed, and AVMs tend to be treated once they are discovered. The incidence of AVMs is approximately 1 per 100 000 per year in unselected populations, and the point prevalence in adults is approximately 18 per 100 000. AVMs account for between 1 and 2% of all strokes, 3% of strokes in young adults, 9% of subarachnoid haemorrhages and, of all primary intracerebral haemorrhages, they are responsible for 4% overall, but for as much as one-third in young adults. AVMs are far less common causes of first presentations with unprovoked seizures (1%), and of people presenting with headaches in the absence of neurological signs (0.3%). At the time of detection, at least 15% of people affected by AVMs are asymptomatic, about one-fifth present with seizures and for approximately two-thirds of them the dominant mode of presentation is with intracranial haemorrhage. The limited high quality data available on prognosis suggest that long-term crude annual case fatality is 1-1.5%, the crude annual risk of first occurrence of haemorrhage from an unruptured AVM is approximately 2%, but the risk of recurrent haemorrhage may be as high as 18% in the first year, with uncertainty about the risk thereafter. For untreated AVMs, the annual risk of developing de novo seizures is 1%. There is a pressing need for large, prospective studies of the frequency and clinical course of AVMs in well-defined, stable populations, taking account of their prognostic heterogeneity.

http://www.saivms.scot.nhs.uk/pdf/resPaper/Brain.pdf

A systematic review of the frequency and prognosis of arteriovenous malformations of the brain in adults

To define more closely the clinical relationship between migraine and intracranial arteriovenous malformation (iAVM), the clinical features of 57 reported instances and of 7 personal cases were analysed. Migraine attacks symptomatic of AVM include: late onset, frequent absence of (familial) migraine history, diminution or even inversion of the usual sex-ratio in migraine, brevity of attacks, disruption of the usual sequence of attack symptoms and, finally. unusual or permanent neurologic deficit. An attempt has also been made to clarify the epidemiological relationship. The reported frequency of migraine in cases of AVM, and AVM in cases of migraine is reflected against an inquiry into the number of annually diagnosed cases of AVM in 20 Dutch neurological/neurosurgical centres, covering 12.106 inhabitants in 8 of the 11 provinces. The annual incidence of migraine is estimated at 1:3,500 population, that of diagnosed iAVM is 120, i.e. 1:100,000. Coincidental occurrence of the two conditions works out at 1:...

Intracranial arteriovenous malformation and migraine.

The differentiation of migraine headache, preceded by visual aura, from cerebral arteriovenous malformation (AVM) is often regarded as difficult A study of 26 patients with occipital lobe AVM revealed two distinct syndromes in 18 patients—occipital epilepsy and occipital apoplexy Occipital epilepsy is characterized either by elementary visual phenomena, such as brief flashes of light, or by dimming of a homonymous field Occipital apoplexy results from hemorrhage and hematoma formation within the occipital lobe and is characterized by sudden headache and homonymous visual field loss We conclude that patients harboring occipital AVMs may, indeed, have visual phenomena and headache that should not be confused with migraine because either a history of generalized seizure or bruits on examination will probably be present

https://jamanetwork.com/HttpHandlers/ArticlePdfHandler.ashx?journal=OPHTH&articleId=631507&pdfFileName=archopht_93_4_002.pdf

Occipital Lobe Arteriovenous Malformations: Clinical and Radiologic Features in 26 Cases With Comments on Differentiation From Migraine

Background Occipital arteriovenous malformations (AVMs) cause a variety of visual disturbances and headaches. Early diagnosis may lead to treatment that reduces the risk of hemorrhages, visual field loss and other neurologic deficits, and death. Methods We reviewed the records of the 70 patients with occipital AVMs referred to New York University Medical Center to investigate the mode of presentation and the outcome of treatment. Results Sixty-eight patients presented with one or more symptoms, including homonymous visual disturbances in 39, headache in 39, seizures in 20, and hemorrhage in twenty-six. Visual field loss was more common (p = 0.0007) and more severe (p = 0.0002) in patients who bled than in those with unruptured AVMs (16/44). The frequency of visual field loss was not associated with calcarine artery supply to the AVM. Prior to treatment, the fields improved in five patients with visual loss associated with a hemorrhage. Forty-six patients were treated with embolization, surgery, radiosurgery, or a combination of therapies. The AVM was eliminated in 19 of 20 patients (nine with preoperative partial embolization) treated with surgery versus in 4 of 27 patients treated only with embolization. There were two AVM-associated deaths, two subarachnoid hemorrhages, and four new neurologic deficits after treatment. Visual fields were worse in 15 patients, unchanged in 22, and improved in eight. Conclusions Whereas some features of headache and visual symptoms are similar for occipital AVMs and migraine, the two disorders are usually distinguishable. Visual field improvement can spontaneously occur in patients who have had loss secondary to an intracerebral bleed. Treatment with embolization or surgery, particularly with surgical excision of the AVM, can result in new or worse visual field loss.

Occipital arteriovenous malformations: Visual disturbances and presentation

OBJECTIVE: To determine whether the rate of detecting a tumour, arteriovenous malformation (AVM) or aneurysm with the use of enhanced or unenhanced computed tomography (CT) is significant in patients with chronic headache and to calculate the cost. DESIGN: Case series. SETTING: Chronic headache clinic at a tertiary care referral centre. PATIENTS: All 373 consecutive patients with chronic headache (284 women, 89 men) referred for CT scanning from May 1987 to October 1992 who met one or more of the following criteria: increased severity of symptoms or resistance to appropriate drug therapy (287 patients [76.9%]), change in characteristics or pattern of headache (78 [20.9%]) or family history of intracranial structural lesion (8 [2.1%]). INTERVENTIONS: CT scans of the head were enhanced with nonionic contrast medium (292 scans), were unenhanced (70) or involved both methods (40). OUTCOME MEASURES: Number and nature of minor and major findings, and total price per scan. RESULTS: Of the 402 CT scans 14 (95% confidence interval [CI] 7 to 21) revealed minor findings that did not alter patient management: infarct (9 scans), cerebral atrophy (2), cavum vergae (1), hyperostosis frontalis interna (1) and communicating hydrocephalus (1). Four scans (95% CI 0 to 8) showed significant lesions: osteoma (2), low-grade glioma (1) and aneurysm (1); only the aneurysm was treated. There were no cases of AVM. An unenhanced scan cost $82.63 and an enhanced scan $204.05. The cost per significant finding was over $18,000. In all, it cost $74,243 to find one treatable vascular lesion. CONCLUSIONS: The detection rate of CT scanning in patients with chronic headache is similar to that expected in the general population, provided the neurologic findings are normal. The cost of detecting intracranial lesions in this patient population is high [corrected].

Sencer W

Papers

A clinical study of cerebral vascular malformations. (the significance of migraine).