Cryptic Vascular Malformation Research Articles

Pathologically Confirmed Cryptic Vascular Malformation as a Cause of Convexity Subarachnoid Hemorrhage

We report a rare case of pathologically confirmed cryptic vascular malformation as a cause of primary convexity subarachnoid hemorrhage (SAH) of unknown etiology. A 48-year-old woman presented with sudden severe headache. Localized right convexity SAH was observed on computed tomography (CT) scan, but the origin could not be detected despite extensive workup covering the entire head by using 3.0-Tesla magnetic resonance (MR) imaging with MR angiography and CT angiography combined with venous-phase imaging with a 320-detector row CT scanner. Subsequent digital subtraction angiography (DSA) performed 2.5 hours after admission failed to reveal any cause of SAH; however, a right frontoparietal avascular region was suspected to be due to a newly developed intracerebral hematoma. The lesion was simultaneously confirmed by angiographic cone-beam CT imaging. Because she remained neurologically intact, we decided to perform a follow-up study later with medical management. However, she developed left hemiparesis 3 hours after DSA. CT scan demonstrated progression of the hematoma, and her symptoms gradually worsened. Emergent surgical exploration along the SAH superficial to the postcentral sulcus and hematoma evacuation were performed, with favorable functional outcome. Pathological examination confirmed cryptic vascular malformation with several abnormally dilated arterioles within the subarachnoid space surrounded by a thick SAH clot. It is important to consider the possibility of ruptured cryptic vascular malformation as a cause of nontraumatic nonaneurysmal convexity SAH when recurrent hemorrhage occurs despite thorough diagnostic workup, because surgical resection may be the only curative treatment option to eliminate the risk of rebleeding and disabling symptoms.

High Incidence of Radiation-Induced Cavernous Hemangioma in Long-Term Survivors Who Underwent Hematopoietic Stem Cell Transplantation with Radiation Therapy during Childhood or Adolescence

Radiation-induced cavernous hemangioma (RICH) is a late complication of cerebral radiation therapy. Long-term survivors of hematopoietic stem cell transplantation (HSCT) who underwent radiation therapy could be at increased risk for RICH. We investigated records of 68 patients who underwent HSCT during childhood or adolescence and were assessed by magnetic resonance imaging (MRI), including T2*-weighted imaging of the brain, annually for 5 years over a range of 6 to 29 years after HSCT. We developed a scoring and grading system for RICH to monitor the process and the progress of radiologic changes. Among the 68 patients investigated, 28 (41.2%) were diagnosed with CH. All 28 patients had received total body irradiation as a conditioning treatment for HSCT and/or cranial radiation therapy before HSCT as part of the treatment of their primary disease. RICH was diagnosed in none of the patients who did not receive radiation (n = 19), in 46.2% of those who received 6 to 12 Gy (n = 39), and in all of those who received 18 to 36 Gy (n = 10). Total RICH scores were correlated with higher radiation doses. Careful and long-term evaluation with MRI, including T2*-weighted imaging, is necessary for HSCT recipients who received radiation therapy before and/or during HSCT.

Neuroimaging in pediatric leukemia and lymphoma: differential diagnosis.

Recent advances in therapy for pediatric hematologic neoplasms have greatly improved the prognosis but have resulted in an increased incidence of associated complications and toxic effects. The main neuroimaging features in pediatric patients with leukemia or lymphoma treated with chemotherapy or radiation therapy were retrospectively reviewed. To simplify the approach and facilitate differential diagnosis, the neuroimaging features have been classified into three main categories: central nervous system manifestations of primary disease, side effects of therapeutic procedures (radiation therapy, chemotherapy, bone marrow transplantation), and complications due to immunosuppression, particularly infections. Manifestations of primary disease include cerebrovascular complications (hemorrhage, cerebral infarction) and central nervous system involvement (infiltration of the meninges, parenchyma, bone marrow, orbit, and spine). Effects of radiation therapy include white matter disease, mineralizing microangiopathy, parenchymal brain volume loss, radiation-induced cryptic vascular malformations, and second neoplasms. Effects of chemotherapy and bone marrow transplantation include hemorrhage, dural venous thrombosis, white matter disease, reversible posterior leukoencephalopathy syndrome, and anterior lumbosacral radiculopathy. Both the underlying malignancy and antineoplastic therapy can cause immunosuppression. Fungi are the most frequent causal microorganisms in immunosuppressed patients with infection. Familiarity with the imaging findings is essential for proper diagnosis of neurologic symptoms in pediatric patients with oncohematologic disease.

Regional association of developmental venous anomalies with angiographically occult vascular malformations.

This study reviews the neuroradiological findings of 43 patients with a developmental venous anomaly in order to discuss the clinical significance of this entity. All patients underwent unenhanced and contrast-enhanced computer tomography and magnetic resonance tomography, as well as selective angiography, and were followed for at least 2 years. In 40% (17 of 43) of patients a cryptic vascular malformation was found in the proximity to the developmental venous anomaly. Neurological symptoms were present in 8 of 17 patients (47%) in this group. Patients with an isolated developmental venous anomaly had symptoms in 19% (5 of 26), but none of them had experienced a hemorrhage. Magnetic resonance was the most sensitive method for the diagnosis of both types of lesions and alterations of the adjacent parenchyma. These results further support that developmental venous anomalies represent a clinically benign entity. However, patients with an association of a developmental venous anomaly and a cryptic vascular malformation are at risk for hemorrhage from their angiographically occult vascular malformation. Magnetic resonance proved to be the imaging modality of choice for both entities and is appropriate for diagnosis and follow-up.

Magnetic resonance imaging and magnetic resonance angiography in long term survivors of acute lymphoblastic leukemia treated with cranial irradiation

Successful treatment of acute lymphoblastic leukemia (ALL) has resulted in an increasing number of patients whose disease is cured. This treatment includes cranial irradiation as prophylaxis against central nervous system relapse. The late effects of irradiation are well documented, but their incidence is unknown. The authors investigated the late effects of this treatment modality further by scanning 35 long term survivors of ALL who received cranial irradiation. Thirty-five survivors of ALL with no known complication of treatment were included in this study. They were examined with magnetic resonance imaging (MRI) of the brain and magnetic resonance angiography (MRA) of the circle of Willis. A control group of 24 patients who were cured of other childhood malignancies without exposure to cranial irradiation also were scanned. Fifteen of 35 (43%) abnormalities were found in the study group versus 4/24 (17%) in the control group. Excluding minor atrophic changes that are known to be produced by irradiation and chemotherapy, there were 9/35 (26%) abnormalities in the study group and 1/24 (4%) in the control group (P < 0.05). These abnormalities included three tumors, a meningioma, a paranasal sinus rhabdomyosarcoma, and an anaplastic astrocytoma. In addition, there were two cases of large vessel vasculopathy, two small cystic infarcts, one diffuse white matter abnormality, and one cryptic vascular malformation. The abnormal control patient had a cerebellar infarct. Complications of cranial irradiation in the treatment of ALL appear to be more frequent than currently are appreciated. That these complications include tumors that are potentially treatable suggests that screening may be valuable for these patients.

Radiation-induced telangiectasia in the brain simulates cryptic vascular malformations at MR imaging.

To analyze the magnetic resonance (MR) imaging, clinical, and pathologic features of radiation-induced telangiectasia of the brain. The clinical and radiation therapy records were reviewed of 20 patients who developed focal hypointense lesions on T2-weighted MR images obtained after radiation therapy of the central nervous system. Pathologic material was reviewed in six patients. Eleven patients had solitary lesions, and nine had multiple foci on MR images. Fourteen of the 20 patients were less than 20 years old. The appearance ranged from small hypointense foci to larger regions of acute hemorrhage. Hematomas occurred at the site of a previously identified focus of T2 shortening in five patients. Pathologic findings included ectatic thin-walled vessels surrounded by hemosiderin and gliosis, with minimal evidence of necrosis. Radiation-induced telangiectasia in the brain results in varying amounts of hemorrhage and, occasionally, parenchymal hematomas, and may appear similar to cryptic vascular malformations on T2-weighted MR images.

Brainstem haematomas: early and late prognosis.

The purpose of the present retrospective study is to analyse 14 patients harbouring brainstem haematomas and to discuss the early and late prognosis. The patients were divided into two groups: group A (survivors), 8 patients with follow-up duration ranging between 8 months and 12 years; and group B (nonsurvivors), 6 patients. At the time of onset or hospital admission, the former were under 50 years of age and had no important clinical history. Their degree of consciousness was altered only slightly or moderately and their brainstem haemorrhages were focal or only slightly diffuse. Three patients in this group underwent surgical treatment. The members of group B, who died within days of their admission to the hospital, were over 60 years of age, had a number of clinical antecedents and severe alterations of consciousness, while 83% of them presented diffuse brainstem haemorrhages. None of the patients of this group were treated surgically. It was concluded that: 1) the indications for surgery for these lesions were progressive hydrocephalus, increase in the mass effect with progressive symptomatology and suspected "cryptic vascular malformation" with risk of later rebleeding or brain tumour; 2) surgical treatment was necessary to improve the symptomatology in 3 patients in group A, although there were no significant differences between surgically treated and nonsurgically treated patients in the same group with respect to prognosis; 3) age, clinical history, degree of alteration of consciousness and type of haemorrhage are the major factors affecting the early and late prognosis of brainstem haemorrhages.

Progression of multiple cryptic vascular malformations associated with anomalous venous drainage

The case of a young girl with a pericallosal venous malformation associated with multiple cryptic vascular malformations (CVM's) is described. The presenting cryptic malformation, which hemorrhaged, was completely excised, but the venous malformation was not. Routine follow-up magnetic resonance images obtained over the past 9 years have documented the development of multiple new cryptic malformations along the radicles of the venous malformation. Magnetic resonance imaging and cerebral angiography revealed venous outflow obstruction at the junction of the venous malformation with the straight sinus. The association of CVM's with anomalous venous drainage patterns and the role of venous hypertension in the pathogenesis of cryptic malformations are discussed. This case suggests that CVM's associated with a venous malformation may recur and new ones may develop if the venous malformation is not excised, particularly if venous hypertension is also present. The likelihood of a surgical cure in these patients may depend on complete excision of both anomalies, which is rarely feasible because of the potentially devastating results of resecting a venous malformation. Alternative treatments for patients with both types of lesions are discussed.

Pediatric cryptic vascular malformations: presentation, diagnosis and treatment.

Since the advent of magnetic resonance (MR) imaging, angiographically occult or 'cryptic' vascular malformations (CVMs) have been detected with increasing frequency in the pediatric population. The natural history of these lesions is uncertain and treatment remains controversial. We respectively reviewed the presentation, radiology, treatment and outcome of 37 pediatric patients with CVMs seen at our institution between 1982 and 1992. MR imaging was diagnostic in all patients studied. Angiography was negative in 20 of 21 patients studied, while 1 teenage girl was found to have a venous malformation. Total surgical excision was the treatment goal in all patients presenting with symptomatic CVMs. There has been no surgical mortality. Perioperative complications occurred in one third of the patients but quickly resolved in most cases. Only 2 patients with multiple CVMs, including brainstem lesions, who presented with progressive neurologic deficits were clearly worse following surgery. Six of seven patients with radiation-induced CVMs have remained asymptomatic with close radiographic follow-up, while 1 patient with a hemorrhage has required surgical evacuation. We conclude that CVMs occur more commonly in the pediatric population than previously assumed. Patients presenting with seizures or hemorrhage should undergo craniotomy with the goal of complete excision. Radiation therapy plays no role in the treatment of these lesions and may actually result in their formation. Careful clinical and radiological follow-up is critical to assess the completeness of surgical removal and to evaluate progression of lesions in patients with multiple or radiation-induced CVMs treated conservatively.

Cervical intramedullary cavernous angioma with MRI-proven haemorrhages

Two contrasting cases of cervical intramedullary cavernous angioma in young female patients are reported. One patient had a 3-year course of step-wise progressive tetraparesis; at each of the five events intramedullary bleeding from a cryptic vascular malformation at C6-7 level was diagnosed by MRI. The other patient presented with one episode which led to MRI diagnosis of a vascular malformation at the C2 level. Both patients eventually underwent complete surgical excision of the angioma with subsequent steady improvement of the neurological deficit.

Magnetic Resonance Imaging of Intractable Complex Partial Seizures: Pathologic and Electroencephalographic Correlation

Prior studies indicate variable usefulness of magnetic resonance imaging (MRI) in the evaluation of patients with complex partial seizures (CPS), but sensitivities as low as 12% have been reported. We analyzed the MRI examinations of 20 patients with medically refractory CPS who later underwent resection of the seizure focus proven by electroencephalography (EEG). MRI studies were correlated with surgical pathology in all patients. Eleven of the 20 CPS patients had mesial temporal sclerosis (MTS). Seven of the 11 (64%) exhibited an MRI abnormality at the site of the EEG-demonstrated histopathologic focus. MRI abnormalities included temporal lobe hypoplasia or atrophy (four patients), and increased signal intensity on long repetition time (TR) sequences (three patients). Four patients had no MRI abnormalities corresponding to the histopathologic focus. Nine of the 20 CPS patients had other abnormalities responsible for the seizures, including astrocytoma, cryptic vascular malformation, hamartoma, polymicrogyria, tuberous sclerosis (forme fruste), arachnoid cyst, and congenital hemiatrophy. No patient had normal MRI studies. Our single most useful MRI sequence was the coronal long TR/dual echo sequence, using cardiac gating and first-order gradient moment nulling to diminish flow-related artifacts that could hinder evaluation of medial temporal lobe structures.

MR imaging in patients with intractable complex partial epileptic seizures.

Detailed neurologic studies, high-field-strength MR imaging, and CT scanning were performed preoperatively in 53 patients with intractable complex partial seizures who underwent surgical treatment for epilepsy. Macroscopic structural (tumoral or vascular) lesions were found in 28% of patients. The remainder had pathologic findings consistent with mesial temporal gliosis. Tumors were found in 22% of the patients and were benign or of low-grade malignancy in every case. MR was accurate in the preoperative diagnosis of structural lesions, including very small occult tumors and cryptic vascular malformations. In patients with mesial temporal gliosis, there was correlation between the MR observation of a unilaterally dilated anterior temporal horn and the EEG-identified seizure focus and side of temporal lobectomy. However, MR demonstrated T2-weighted signal abnormalities correlating with the epileptogenic focus in only 8% of cases of mesial temporal gliosis. MR provided useful information in 28% of patients who underwent surgery for refractory complex partial epilepsy. MR obviated invasive EEG monitoring in 93% of the patients with structural lesions. MR was useful in only 8% of the patients with pathologic changes of mesial temporal gliosis.

Cryptic vascular malformations of the spinal cord: diagnosis by magnetic resonance imaging and outcome of surgery

The cases of seven patients with intramedullary, cryptic vascular malformations of the spinal cord are reported. In all patients, the clinical course was progressive; a Brown-Séquard syndrome was the most common presenting symptom complex. Magnetic resonance (MR) imaging was performed in all patients. The pattern seen most often was a focus of high signal (on both T1- and T2-weighted MR images) surrounded by a larger zone of low signal (best seen on T2-weighted images), and was remarkably similar for all patients. Six patients underwent surgical exploration; removal of the lesions halted the progression of symptoms in five patients, and one patient had worsened sensory function after surgery. Motor function did not decrease postoperatively in any patient. The one patient who refused surgery has continued to decline neurologically. Histopathological examination of surgical specimens showed a cavernous malformation in one patient, a venous malformation in one, venous varices in two, and organizing hematomas in two; these findings are markedly different from those in previously reported cases of cryptic vascular malformations.

Differential diagnosis between tumoural and non-tumoural intracranial lesions in children: a stereotactic approach.

The rational management of intracranial lesions should be based on the exact definition of the nature of the lesions and, when it is possible, on their spatial definition. Since External Radiotherapy (ERT) and cytostatic therapy are not free of undue effects, especially in children, such treatments should be used only when a "sure" diagnosis is obtained. The aim of this paper is to study the results allowed by the Talairach's stereotactic methodology in children. During the period January 1979-December 1986, 704 stereotactic procedures including serial biopsies, were performed at the S. Anne Hospital in Paris. One hundred forty-eight procedures (21%) concerned 134 children (78 M; 56 F) aged from 2 to 16 years. The interval between the occurrence of the first clinical symptoms and the stereotactic procedures varied between 1 and 180 months (m: 24 m). Fifty-two (40%) had previous therapeutic procedures without precise diagnosis. The lesions were hemispheric in 46 (34%) and deep seated in 88 (66%). The serial stereotactic biopsies proved the existence of a non-tumoural lesion in 20 children (14.9%): (cryptic vascular malformation: 5, cortical dysplasia: 3, haematoma: 3, ischaemia: 1, granuloma: 1, degenerative pathology: 2, cicatrix: 2, post-ERT alterations: 1, arachnoidal cyst: 2). Four were in the brain stem. In 3 patients (2%), a precise diagnosis was not obtained. The CT scan characteristics of the 20 non-tumoural lesions did not permit to establish a precise differential diagnosis. The therapeutic management was adapted to the diagnosis, avoiding potentially dangerous procedures in the 20 non-tumoural lesions.

Cryptic vascular malformations diagnosed by stereotactic biopsies--a preliminary study.

A series of 14 cryptic vascular malformations (CVM) deeply situated or localized in functional cortical areas were diagnosed by serial stereotactic biopsies. No history was suggestive of hemorrhage, despite a substantial hematoma being evacuated during biopsy procedures in 4 patients. Retrospectively, CVM without hematoma were found to have certain characteristics that should raise the suspicion as to the correct diagnosis. At the time of discharge from the hospital, only 1 patient had mild aggravation of a preexisting motor deficit, which further improved. Serial stereotactic biopsies provided the required histological diagnosis with relatively low risk.

Organized Expanding Spontaneous Intracerebral Hematoma

The authors report a case of massive spontaneous intracerebral hematoma in a infant, caused by bleeding from cryptic vascular malformation associated with vitamin K dependant factor deficiency. The bleeding was initiated by vitamin K dependant factor deficiency, then 3 weeks later hematoma was expanded by rebleeding from malformed vessel after PT and PTT had been returned to normal values. The well circumscribed organized old hematoma with fresh expanded bleeding component within a huge rusty colored cystic fluid cavity was recognized in operative field and pathological ground.

Spontaneous brain stem haematoma.

Thirty-four cases of brain stem haematoma encountered in the past eight years were surveyed. Among these, three cases had haematomas caused by cryptic vascular malformations. These cases underwent direct operation (removal of haematoma) and are well and working. The haematomas of the other 31 cases were probably of hypertensive origin. Among them, eight cases with haematomas less than one cm in the largest diameter as shown in the CT (Group A), survived more than one month and six of them are still living, four of them working. In cases with a haematoma more than one cm in the largest diameter on the CT (Groups B and C), 13 cases died and four cases are living. Indications for operation are doubtful even for cases of Group A, except for cases with acute hydrocephalus or cases with suspected cryptic angiomas.

Cryptic vascular malformations involving the brainstem.

Six patients with angiographically cryptic vascular malformations involving the brainstem were examined with computed tomography (CT). The clinical and CT findings of cryptic vascular malformations of the brainstem are described and distinguished from those of brainstem glioma and multiple sclerosis. Calcification within a brainstem lesion that displays relatively little mass effect and shows little contrast enhancement, particularly when associated with a long history of waxing and waning brainstem symptoms, should suggest a vascular malformation.

Clinical and computed tomographic findings in thrombosed and cryptic cerebrovascular malformations

Ten patients with angiographically occult or thrombosed cerebrovascular malformations were analyzed. Seven patients initially presented with an episode of intracranial hemorrhage; three others presented with a seizure disorder. CT showed hyperdense (9) or isodense (1) lesion; the hyperdense portion was proven to be hematoma in 3. Enhancement was seen in 6 cases and was absent in 4. Angiography showed either avascular mass (7) or was normal (3). In 2 cases, angiographic studies showed non-visualization of abnormal vessels on repeat study. In a review of 200 cases of spontaneous intracerebral hemorrhage, nine young patients had CT evidence of an acute hematoma but no angiographic or pathological evidence of abnormal vessels; and it was postulated that these represented cryptic vascular malformations or aneurysms. The clinical prognosis for both the angiographically occult (thrombosed) or cryptic cerebrovascular malformations was better than reported in previous studies.

Cryptic vascular malformation of the choroid plexus

A 45-year-old man and a 47-year-old woman with cryptic vascular malformations of the choroid plexus in the lateral ventricle are reported. Each patient had an intraventricular hematoma, located in the right trigone and in the anterior part of the left lateral ventricle, respectively. The vascular lesion of one patient was angiographically visualized as find abnormal vessels communicating with the right anterior choroidal artery; in the other, angiography did not reveal the lesion. In the former patient, histological examination of the excised specimen led to a diagnosis of arteriovenous malformation; in the latter, a diagnosis of venous malformation was made. Both patients were successfully treated surgically.