Occult Arteriovenous Malformation Research Articles

Case report: Surgical treatment of combined dural arteriovenous fistula and angiographically occult arteriovenous malformation complicated by intracerebral hemorrhage

Background. Cerebral arteriovenous malformations and dural arteriovenous fistulas are relatively rare pathologies with frequency of 1–1.5 and 0.1–0.2 cases per 100 000 people per year, respectively. Probability of a combination of these pathologies in a single patient is extremely low. The authors were not able to find publications describing a combination of these pathologies of the cerebral vasculature.Aim. To present a clinical case of successful surgical treatment of combined cerebral pathology – dural arteriovenous fistula and angiographically occult arteriovenous malformation – in a patient with intracranial hemorrhage.Materials and methods. Analysis of the results of treatment of patient with dural arteriovenous fistula with hemorrhagic disease course at the N.V. Sklifosovsky Research Institute of Emergency Medicine (Moscow) was performed. The patient underwent osteoplastic cranial trepanation, resection of the dural arteriovenous fistula. Intraoperatively an angiographically occult arteriovenous malformation was detected which caused the hemorrhage.Results. Surgical treatment allowed to achieve a satisfactory outcome. Intraoperatively diagnosed angiographically occult arteriovenous malformation was confirmed histologically.Conclusions. The presented clinical observation shows the necessity of careful revision of hematoma cavity in the presence of isolated intraparenchymal hemorrhage from dural arteriovenous fistula.

Unruptured Arteriovenous Malformations in the Multidetector Computed Tomography Era: Frequency of Detection and Predictable Failures.

Objectives:While hemorrhage arising from ruptured arteriovenous malformations (AVMs) is usually evident on multidetector non-contrast computed tomography (NCCT), unruptured AVMs can be below the limits of detection. We performed a retrospective review of NCCT of patients with a proven diagnosis of unruptured AVM to determine if advances in CT technology have made them more apparent and what features predict their detection.Material and Methods:Twenty-five NCCTs met inclusion criteria of having angiography or MR proven AVM without hemorrhage, prior surgery, or other CNS disease. Demographic variables, clinical symptoms at presentation, abnormal CT imaging findings, attenuation of the superior sagittal sinus (SSS), and Spetzler-Martin grade of each AVM were recorded. We examined the relationship between AVM detection and SSS attenuation through Kruskal–Wallis test. Exploratory serial logistic principal components analysis was performed including demographics, symptoms, and CT features in the multivariate model.Results:About 80% of the NCCTs showed an abnormality while 20% were normal. All those with an identifiable abnormality showed hyperdensity (80%). Logistic regression models indicate that clustered associations between several CT features, primarily calcifications, hyperdensity, and vascular prominence significantly predicted Spetzler-Martin grade (likelihood ratio 7.7, P = 0.006). SSS attenuation was significantly lower in subjects with occult AVMs when compared to those with CT abnormalities (median 47 vs. 55 HU, P < 0.04).Conclusion:Abnormal hyperdensity was evident in all detectable cases (80%) and multiple CT features were predictive of a higher Spetzler-Martin AVM grade. Moreover, SSS attenuation less than 50 HU was significantly correlated with a false-negative NCCT.

Leg ulcer due to multiple arteriovenous malformations in the lower extremity of an elderly patient

A 66-year-old woman with a history of deep vein thrombosis (DVT) presented with an irregularly shaped leg ulcer surrounded by pigmentation on the left lower limb. In addition, the circumference of her left thigh had gradually increased. The ulcer did not respond to topical treatment and enlarged, therefore, she visited our hospital. Arteriography of the left lower limb showed multiple arteriovenous malformations (AVMs), based on which we made a diagnosis of a leg ulcer due to multiple AVMs. Transcatheter arterial embolisation with a mixture of N-butyl-2-cyanoacrylate and lipiodol was performed six times in the period of about a year for treating the AVMs. The ulcer was managed with bed rest, surgical debridement, continuous pressure support with elastic wrap and topical treatment. After 15 months, the ulcer healed, leaving pigmentation and scarring. It is quite rare for AVMs to progress in the elderly. We speculate that the DVT had caused occult AVMs to become symptomatic following an increase in size.

A case of severe multiple injuries due to a traffic accident with an intracerebral hemorrhage possibly caused by the rupture of an angiographically occult arteriovenous malformation

交通外傷で搬送された重症多発外傷例で，angiographically occult arteriovenous malformation（AOAVM）が脳内出血の原因と考えられた症例を経験した。症例は24歳女性。自家用車を運転中に交差点での単独事故で受傷した。近医へ救急搬送されたが高エネルギー外傷のため当院へ紹介された。来院時の脳CTで脳挫傷を伴わない右被殻出血を認めた。またinjury severity scoreは48点であった。IIIa型腎損傷に対してtranscatheter arterial embolizationを施行した。右大腿骨骨折に対して鋼線牽引を施行した。外傷性播種性血管内凝固症候群を呈しており新鮮凍結血漿を含めた大量輸血を要した。3時間後の経過観察CTで脳内出血の増大を認めたため，AVMが原因と推察し脳血管撮影を施行したが，明らかな異常血管を認めなかった。来院6時間後のCTで切迫脳ヘルニアが出現し緊急開頭血腫除去術を施行した。術中所見では血腫の中に異常血管が認められ，病理組織検査でAVMと診断した。若年発症例や高血圧が併存しない脳内出血症例の場合，鑑別診断にAOAVMを考慮すべきである。

Angiographically occult vascular malformation of the third ventricle

Angiographically occult vascular malformations (AOVM) are cerebrovascular malformations that are not demonstrable on cerebral angiography. The majority of AOVMs located in the third ventricle are cavernous malformations. To the best of our knowledge an angiographically occult arteriovenous malformation (AOAVM) of the third ventricle has not been previously reported. We report an unusual vascular malformation of the third ventricle presenting with hydrocephalus due to mass effect, verified histopathologically as an AOAVM.

Recurrent Caudate Hemorrhage Caused by an Occult Arteriovenous Malformation Evaluation of Patients With Recurrent Hemorrhage

Recurrent Caudate Hemorrhage Caused by an Occult Arteriovenous Malformation Evaluation of Patients With Recurrent Hemorrhage

A combined syndrome of juvenile polyposis and hereditary haemorrhagic telangiectasia associated with mutations in MADH4 (SMAD4)

Juvenile polyposis and hereditary haemorrhagic telangiectasia are autosomal dominant disorders with distinct and non-overlapping clinical features. The former, an inherited gastrointestinal malignancy predisposition, is caused by mutations in MADH4 (encoding SMAD4) or BMPR1A, and the latter is a vascular malformation disorder caused by mutations in ENG (endoglin) or ACVRL1 (ALK1). All four genes encode proteins involved in the transforming-growth-factor-beta signalling pathway. Although there are reports of patients and families with phenotypes of both disorders combined, the genetic aetiology of this association is unknown. Blood samples were collected from seven unrelated families segregating both phenotypes. DNA from the proband of each family was sequenced for the ACVRL1, ENG, and MADH4 genes. Mutations were examined for familial cosegregation with phenotype and presence or absence in population controls. Findings No patient had mutations in the ENG or ACVRL1 genes; all had MADH4 mutations. Three cases of de-novo MADH4 mutations were found. In one, the mutation was passed on to a similarly affected child. Each mutation cosegregated with the syndromic phenotype in other affected family members. Mutations in MADH4 can cause a syndrome consisting of both juvenile polyposis and hereditary haemorrhagic telangiectasia phenotypes. Since patients with these disorders are generally ascertained through distinct medical specialties, genetic testing is recommended for patients presenting with either phenotype to identify those at risk of this syndrome. Patients with juvenile polyposis who have an MADH4 mutation should be screened for the vascular lesions associated with hereditary haemorrhagic telangiectasia, especially occult arteriovenous malformations in visceral organs that may otherwise present suddenly with serious medical consequences.

The value of screening for multiple arterio-venous malformations in hereditary hemorrhagic telangiectasia: a diagnostic study.

Occult visceral arterio-venous malformations (AVMs) may be a constant threat to patients suffering from hereditary hemorrhagic telangiectasia (HHT), also known as Rendu-Osler-Weber syndrome (M. ROW). HHT patients predominantly become symptomatic through chronic, recurrent epistaxis, a symptom that can alert physicians at an early stage of the disease. The purpose of this study was to investigate whether occult, visceral arterio-venous malformations could be detected by screening imaging studies in patients suffering from HHT. In a comprehensive diagnostic study, Rendu-Osler-Weber patients were examined for potential visceral arterio-venous malformations by physical examination and non-invasive imaging techniques. The Department of Otolaryngology of the Philipps University of Marburg is a major referral center and coordinated the screening procedures. Thirty-five individuals with the presumed diagnosis of HHT gave informed consent to the screening investigations. Eighteen of 35 individuals were found to suffer from visceral vascular malformations; most of the AVMs were diagnosed in the lung, but also the liver, spleen, brain and eyes were affected. Six patients could be treated preventively by arterial embolization for AVMs of the lung, liver and brain. Comprehensive screening for occult AVMs in HHT patients seems to be justified to avert potential complications in this group of patients.

Role of Superselective Angiography in the Detection and Endovascular Treatment of Ruptured Occult Arteriovenous Malformations

Three cases of occult micro-arteriovenous malformations not identified by cerebral angiography or other imaging modalities were detected by superselective angiography. The first case had a small intracerebral hemorrhage in the superior colliculus, the second had a perimesencephalic subarachnoid hemorrhage, and the third presented with intracerebral hemorrhage combined with massive intraventricular hematoma. While repeated selective cerebral angiography (four-vessel study) was negative, superselective angiography clearly demonstrated each lesion with small early venous filling in accordance with the location of hematoma. Successful superselective embolization with polyvinyl alcohol particles was performed in each micro-arteriovenous malformation by flow-guided microcatheter without postoperative complications. Our experience suggests that superselective angiography is necessary to visualize micro-arteriovenous malformations in patients with cerebral hemorrhage and negative four-vessel angiography. Furthermore, the superselective endovascular approach has the advantage of offering immediate obliteration of the micro-shunt, thereby reducing or eliminating the risk of further hemorrhage.

Mechanisms of second and further strokes

OBJECTIVESThe mechanisms underlying recurrent stroke may be complex and multifactorial, but they have not been studied systematically. The aim was to analyse the different patterns and pathophysiological mechanisms of second...

Mechanisms of second and further strokes

OBJECTIVES The mechanisms underlying recurrent stroke may be complex and multifactorial, but they have not been studied systematically. The aim was to analyse the different patterns and pathophysiological mechanisms of second and further strokes. METHODS Recurrent stroke patterns and mechanisms were studied in 102 patients admitted with second or further strokes to the stroke centre in Lausanne University Hospital. RESULTS The patients with an initial cardioembolic stroke experienced recurrent stroke of the same type most often, followed by those with initial non-lacunar non-cardioembolic stroke, brain haemorrhage, and lacunar stroke (77%, 65%, 58%, and 48% respectively). Forty two per cent of the recurrent strokes in patients with an initial brain haemorrhage were ischaemic, whereas patients with ischaemic stroke only occasionally suffered brain haemorrhage (5%). In patients with brain haemorrhage, the lobar location predominated in both the first and all episodes (69% and 78% respectively), suggesting a small, occult arteriovenous malformation or cerebral amyloid angiopathy rather than hypertensive small artery disease. The functional disability of patients after an initial lacunar stroke was significantly better than in patients with other stroke subtypes (p CONCLUSIONS Most of the recurrent strokes were of the same type as the first episode for both cardioembolic and non-lacunar non-cardioembolic stroke, however, about half of the patients with an initial brain haemorrhage or a lacunar stroke experienced other types of stroke recurrently. The findings suggest that the coexistence of multiple aetiologies may play a major part in determining the mechanism of stroke recurrence. The study is an important step in understanding the patterns of stroke recurrence, which may be critical for better prevention.

頭蓋内腫よう病変の術中カラードプラ超音波の使用経験

Recently, noninvasive demonstration of major cerebral arteries has become possible by using transcranial color-coded duplex sonography. We carried out neurosurgical operations in 11 patients with brain tumor and in 1 patient with vascular malformation employing intraoperative Brightness mode (B-mode), color flow imaging and power Doppler imaging (CFI and PDI) to identify mass lesions and, the brain and vascular structure. Ultrasound imaging was performed with an Ultramark 9 HDI (Advanced Technology Laboratories, U.S.A.) using various kinds of scanning probe. Real-time monitoring of B-mode imaging aids in guidance when biopsy probes are applied for brain tumor biopsy as well as in the identification of the localization of tumor masses. CFI and PDI can also demonstrate major cerebral vessels and improve our understanding of the context of brain structure and pathological lesions. PDI was able to reveal slow flow at occult arteriovenous malformations, which failed to be depicted as flow vessels by angiography. In conclusion, intraoperative ultrasound imaging may be useful as a mean of real time monitoring and assists us in performing neurological operations safely.

Ruptured Occult Arteriovenous Malformation Associated with an Unruptured Intracranial Aneurysm

Ruptured Occult Arteriovenous Malformation Associated with an Unruptured Intracranial Aneurysm

Marked Growth of a Cerebral Arteriovenous Malformation: Case Report and Review of the Literature

A case demonstrating the marked growth of an angiographically occult arteriovenous malformation is presented. A review of 58 cases in which an increase in the size of an arteriovenous malformation occurred suggested that the patient's initial age may have had an important role in such growth and that both the age and the duration of follow-up were related to the extent of growth. Follow-up neuroradiological examinations are thought to be necessary for patients who have had an episode of intracranial hemorrhage of unknown cause during childhood, even if the initial angiograms revealed no vascular lesion.

Marked growth of a cerebral arteriovenous malformation

A case demonstrating the marked growth of an angiographically occult arteriovenous malformation is presented. A review of 58 cases in which an increase in the size of an arteriovenous malformation occurred suggested that the patient's initial age may have had an important role in such growth and that both the age and the duration of follow-up were related to the extent of growth. Follow-up neuroradiological examinations are thought to be necessary for patients who have had an episode of intracranial hemorrhage of unknown cause during childhood, even if the initial angiograms revealed no vascular lesion.

“Angioglioma” and the arteriovenous malformationglioma association

The term "angioglioma" denotes a highly vascular glioma, most of which are low-grade lesions associated with a favorable prognosis. The authors encountered an example of this pathology, a cystic oligodendroglioma associated with prominent vasculature which both clinically and histologically mimicked an occult arteriovenous malformation (AVM). This case and reports of the association of AVM and glioma prompted a histological review of 1034 surgically resected AVM's, both angiographically occult and visible, among which no oligodendroglial or astrocytic forms of "angioglioma" were found. Eight cases were observed, however, wherein oligodendroglial cells were increased in number within or about the malformation. Two basic histological patterns of oligodendroglial cell excess were seen; one appeared to be malformative in nature with abnormal disposition of oligodendroglial cells being an integral part of the AVM, whereas in the other an apparent increase in cellularity seemed the result of chronic ischemia with condensation of white matter. It appeared that the areas of increased oligodendrocyte content seen in association with AVM are non-neoplastic lesions that exhibit two rather distinct histological patterns of differing origin. In an effort to determine the frequency of "angioglioma," the authors examined Tissue Registry data for several glioma groups in which highly vascular examples are prone to occur. Tumors selected for study included 104 cerebellar-type (pilocytic) astrocytomas, 82 oligodendrogliomas, and 51 supratentorial pilocytic astrocytomas. Histological hypervascularity mimicking a vascular malformation (that is, an "angioglioma") was encountered in 5%, 4%, and 12% of the cases, respectively. Based upon clinical, radiological, and pathological reviews of these cases, as well as a careful review of the literature, it was concluded that 1) "angiogliomas" are neither rare nor represent a distinct clinicopathological entity; 2) in histological but not necessarily angiographic surgical terms, they represent simply highly vascular gliomas, usually of low grade; and 3) the clinicopathological and angiographic features as well as the prognosis of such lesions do not differ from those of similar gliomas without angioma-like vasculature. Finally, "angiogliomas" must not be confused with gliomas of high-grade malignancy which, due to neovascularity, may be highly vascular at angiography and at surgery.

Association of cerebral arteriovenous malformation and cerebral aneurysm. Diagnosis and management

Between 1979 and 1989, 7 patients were admitted, with cerebral arteriovenous malformations (AVM) and associated aneurysms (7% of the AVM patients and 2% of the aneurysm patients admitted during the same period). 6 of these patients were admitted because of an intracranial haemorrhage (in 3 of them the AVM, angiographically occult, was discovered at surgery). The last patient was referred for seizures. Preoperatively it was supposed that the haemorrhage was related to the aneurysm in 3 cases, and to the AVM in 3 cases. But surgery allowed one to correct this supposition. Haemorrhage was due to AVM rupture in all 6 cases, and no aneurysm had ruptured. Overall three situations were demonstrated in this series: aneurysm and occult AVM (3 cases); AVM and independent aneurysm in the same area (2 cases); large AVM and aneurysm on a feeding artery (2 cases). All 6 patients admitted for haemorrhage were operated upon, at one operation in 5 of them. Both the malformations were excluded in these six patients. For the patient admitted for seizure, intra-vascular embolization of the AVM was performed, the aneurysm was not treated. The pathogenesis of the association AVM-aneurysm is discussed. In the authors' opinion, haemodynamic relationship should be considered in two cases (large AVM and aneurysm on a feeding vessel). For the other 5 cases, both the AVM and the coexisting aneurysm may be the end-result of a common congenital vascular malformation syndrome.

Successful removal of an angiographically occult arteriovenous malformation of the ventral medulla

A case with an angiographically occult arteriovenous malformation (AVM) of the ventral medulla presenting with progressive motor and sensory deficits is reported. The AVM, about 1 x 1 x 0.5 cm in size, accompanied by intramedullary haematoma, was successfully removed through a small incision placed in the right ventrolateral medulla between the vagus and the hypoglossal nerves. The patient's neurological symptoms improved after surgery.

多発性脳動静脈奇形の2症例

We report the cases of two patients, each of whom had two separate angiographically demonstrable intracerebral arteriovenous malformations (AVMs). One patient had an intraventricular hemorrhage with AVMs in the basal ganglia and the insula on the left side, and the other had a pontine hemorrhage with AVMs in the pons and the occipital lobe on the right side. The AVMs in the former patient were totally removed without residual neurological deficit. We discuss the diagnostic problems of multiple intracerebral AVMs and stress the need for thorough neuroradiological evaluation so as not to miss an occult AVM. We also stress the necessity of total excision of all the lesions and point out several problems faced in surgery for AVMs.

Multiple Intracerebral Arteriovenous Malformations: Report of Two Cases

We report the cases of two patients, each of whom had two separate angiographically demonstrable intracerebral arteriovenous malformations (AVMs). One patient had an intraventricular hemorrhage with AVMs in the basal ganglia and the insula on the left side, and the other had a pontine hemorrhage with AVMs in the pons and the occipital lobe on the right side. The AVMs in the former patient were removed totally without residual neurological deficit. We discuss the diagnostic problems of multiple intracerebral AVMs and stress the need for thorough neuroradiological evaluation so as not to miss an occult AVM. We also stress the necessity of total excision of all the lesions and point out several problems faced in surgery for AVMs.