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R Leblanc

Publications and source records attributed to R Leblanc.

At least 37 records · Page 2Linked to original sources
PubMed1996

Familial cerebral aneurysms. A bias for women.

BACKGROUND AND PURPOSE: We evaluated the influence of gender on the formation and rupture of familial cerebral aneurysms. METHODS: We studied 30 patients with ruptured cerebral aneurysms from 14 consecutive families. These patients were compared with the patients with sporadic aneurysms reported by the first Cooperative Study. RESULTS: Eighty percent of familial aneurysms occurred in women versus 59% of sporadic aneurysms (P < .05, chi 2 test). This overrepresentation of women occurred at below the age of 50 years, where 78% of patients with familial aneurysms were women compared with 45% for sporadic aneurysms (P < .01, chi 2 test). Above this age, there was no statistical difference in incidence of familial aneurysms in men or women compared with sporadic aneurysms. In women with familial aneurysms, rupture occurred before the age of 50 years in 59%, compared with 31% for sporadic aneurysms (P < .01, chi 2 test). In four of five families, aneurysms ruptured within 10 years of each other in sisters (mean, 6 years). Multiple aneurysms were equal in both groups (17%), but multiple familial aneurysms occurred mainly in women. There was no difference in the site of single cerebral aneurysms in either group, but familial aneurysms in females occurred at the same site in five of eight families (62%) and in 11 of 17 mother-daughter or sister pairs (65%), compared with 20% for two randomly selected sporadic aneurysms (P < .01). CONCLUSIONS: There is an overrepresentation of women with ruptured familial aneurysms compared with those with sporadic aneurysms. Familial aneurysms rupture in females predominantly before the age of 50, in the same decade, and at the same site within families in the majority of cases. These observations support a possible genetic cause for cerebral aneurysms and a possible hormonal contribution to their rupture.

Adult↗
PubMed1996

Hereditary neurocutaneous angiomatosis. Report of four cases.

The authors report the coexistence of vascular nevi (hemangiomas and arteriovenous malformations (AVMs) of the skin) with AVMs and venous malformations of the brain in male siblings from two related but nonconsanguineous families of three generations. The proband, his siblings, parents, aunts, uncles, and cousins were examined, underwent magnetic resonance (MR) imaging and MR angiography, and when appropriate, cerebral angiography. A father had vascular nevi and a mother, his sister, had an azygos anterior cerebral artery. No other cutaneous or cerebrovascular malformations were present in the parents. Each of the two families had two boys and one girl, 9 to 18 years of age. All the children had vascular nevi and all of the boys had coexisting cerebrovascular malformations: AVMs in three, and a venous malformation in another. One boy had three cerebral AVMs. Two boys had a cerebral hemorrhage, and one also had focal motor seizures. The skin lesions were not those of the Sturge-Weber-Dimitri, Rendu-Osler-Weber, or Wybum-Mason syndromes. The association of cutaneous and cerebrovascular malformations was seen only in males in these families. but females have also been reported in the literature. The results obtained in these families and three other families reported from Western and Central Europe indicate that the association of cerebral and cutaneous vascular hamartomas constitutes a distinct, hereditary clinicopathological entity with autosomal dominant inheritance and variable penetrance. The clinical manifestations of this syndrome are visible, painful vascular nevi, epilepsy, cerebral hemorrhage, and focal neurological deficits. The preponderance of male patients with the full expression of the syndrome suggests a possible hormonal influence on the expression of the gene.

Adolescent↗
PubMed1995

Surgery of unruptured, asymptomatic aneurysms: a decision analysis.

BACKGROUND: Asymptomatic cerebral aneurysms are diagnosed more frequently since the advent of computed tomography and magnetic resonance imaging. Their management is currently empirical. We have used decision analysis to place it on a more analytical basis. METHODS: Decision analysis was used to determine the benefit in years of survival free of sequelae resulting from elective surgery of unruptured aneurysms over natural history. We took 2% as the annual rate of rupture (r), 73% as the risk of death or disability with rupture (M), and 6.5% for the average risk of elective surgery (S). Benefit was calculated from the equation L([1-(1-r)L]M/2-S) [1] for life expectancy (L) corresponding to each quinquennial age group from age 15 to 100 years. Sensitivity analysis was performed to take into account increasing risk of elective surgery based on the size, and accessibility of the aneurysm, and variable risks of rupture and outcome. RESULTS: A gain of at least one year of survival free of neurological sequelae is achieved by surgery compared to natural history for patients whose life expectancy is 19.5 years, corresponding to age 63.5 years for males and 68 years for females. The life expectancy at which a benefit accrues is longer (the patient is younger) for larger, less accessible aneurysms, for lower rates of rupture, and for lesser risks of death or disability from rupture. CONCLUSIONS: Elective surgery of unruptured asymptomatic aneurysms achieves an increased survival over the natural history of at least one year free of neurological sequelae in patients whose life expectancy is 19.5 years or more, using our baseline assumptions. Using equation [1], the corresponding life expectancy producing this benefit can be calculated to account for the increased surgical risk of large, poorly accessible aneurysms and for factors affecting natural history.

Adolescent↗
PubMed1995

Periventricular and subcortical nodular heterotopia. A study of 33 patients.

Grey matter heterotopias, demonstrated by MRI, may present with a broad spectrum of clinical severity. We have studied 33 patients with periventricular nodular heterotopias (PNH); 19 (58%) had unilateral and 14 (42%) bilateral lesions. Thirteen of the 19 patients (68%) with unilateral subependymal nodules of grey matter had, in addition, unilateral focal subcortical heterotopias (SNH), comprising 39% of the entire group. Most had normal intellectual and motor function but some presented with mild mental retardation and neurological deficits. Recurrent seizures were described in 82%, mainly partial attacks with temporo-parieto-occipital auras. Nodular heterotopias led to unilateral or bilateral independent temporal epileptic discharges in 47% of epileptic patients with PNH alone and in 61% of those who had SNH in addition. Extratemporal or multilobar, unilateral or bilateral interictal spiking was present in 10 other patients (36%). Two first degree relatives of patients with seizures were affected but had no seizures, three were investigated for other apparently unrelated neurological symptoms: memory impairment, vertigo or transient ischaemic attacks in one person each. Contiguous ovoid nodules of grey matter, symmetrically lining both lateral ventricles, were described in nine patients. Seven of them were female, including four with familial incidence of PNH. Such lesions may explain the familial occurrence of epilepsy in some families. Seven patients underwent anterior temporal resection: two patients with unilateral subependymal and focal subcortical heterotopias were seizure free or significantly improved. Four patients, three with PNH alone and one with additional subcortical nodules, did not improve significantly after surgery. The remaining patient was followed for less than 6 months.

Adolescent↗
PubMed1995

Subacute enlarging cerebral hematoma from amyloid angiopathy: case report.

We report the case of a 74-year-old woman who, during a 36-hour period, developed progressive, focal neurological deficits and eventual coma associated with a spontaneously enlarging intraparenchymal hematoma resulting from cerebral amyloid angiopathy. The subacute, progressive enlargement of the hematoma, confirmed by serial computed tomographic scans, supports the hypothesis that hematomas enlarge in amyloid angiopathy as a result of the replacement of the contractile elements of the arterial wall by noncontractile amyloid protein. This interference with vasoconstriction, the first phase of hemostasis, may be supplemented by local endothelial dysfunction causing alterations in the chemical mediators of hemostasis, thereby promoting hemorrhage and hematoma enlargement.

Acute Disease↗
PubMed1995

Three-dimensional computed tomographic angiography of cerebral aneurysms.

We describe our technique and results of dynamic, reconstructed, three-dimensional (3-D) computed tomographic (CT) angiography in our first 18 patients with either complex aneurysms, producing subarachnoid hemorrhage or the compression of neighboring structures, or small asymptomatic aneurysms, and assess the role of this technique in treatment planning. A dynamic, infused CT scan producing 1.5-mm cuts of the area of interest was performed, and the two-dimensional images were reconstructed in three dimensions with the ISG Allegro system (ISG Technologies, Toronto, Ontario, Canada). Results were compared with intra-arterial digital subtraction angiography and magnetic resonance angiography. All aneurysms over 3 mm and half of the aneurysms less than or equal to 3 mm were demonstrated by 3-D CT angiography. The neck of the aneurysm, its relationship to the parent artery and associated branches, and its relationship to surrounding bony structures, such as the anterior clinoid, were also demonstrated. This was especially useful for ophthalmic aneurysms. The 3-D image could be rotated on the screen to mimic the operative approach. The active, filling portion and the thrombosed part of partially thrombosed, giant aneurysms could be seen on the same image, and the active, filling portion could be better appreciated with 3-D CT angiography than with magnetic resonance angiography. A partially treated, acrylic-coated aneurysm that could not be completely assessed otherwise has been demonstrated by this technique. 3-D CT angiography is useful in the evaluation of aneurysms, especially when the local anatomy is obscured or distorted by its mass or by the anterior clinoid.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Familial cerebral aneurysms: a study of 13 families.

Despite the recent interest in familial cerebral aneurysms, the epidemiology, natural history, pattern of inheritance, screening of asymptomatic relatives, and the search for a biochemical marker remain problematic. To assess these issues, we report the results of our prospective study of 30 patients with 38 aneurysms (27 ruptured) and of the angiographic screening of asymptomatic relatives, all from 13 families seen consecutively since 1986. Women were over-represented (77%), and patients with multiple aneurysms (17%) were under-represented, compared with sporadic cases. Only 16% of the aneurysms were at the anterior communicating artery. Aneurysms occurred at the same or at the mirror site in 10 of 16 siblings (62%) and in 50% of mother-daughter pairs versus 20% for randomly selected, sporadic aneurysm patients. Rupture occurred in the same decade in 10 of 12 siblings (83%) versus the expected 21% for randomly selected, sporadic aneurysms. The average age at rupture was 47.2 years, and 60% of patients with a ruptured aneurysm were 50 years of age or younger. Seventy percent of patients died or were disabled from aneurysmal rupture. Screening of 41 individuals, including 2 dizygous twins, identified 1 aneurysm and 2 infundibula. A specific pattern of inheritance could not be ascertained from the pedigrees. The presence of an aneurysm was not associated with a specific human leukocyte antigen haplotype or antigen, and collagen Type III was qualitatively and quantitatively normal. Until a biological marker is identified, angiographic screening by intra-arterial digital subtraction or magnetic resonance angiography remains the only way to identify patients at risk of harboring a familial cerebral aneurysm.

Adult↗
PubMed1995

Retained language in dysgenic cortex: case report.

Since the advent of magnetic resonance imaging, there has been renewed interest in disorders of cortical migration in the cause of focal epilepsy. The function of dysplastic cortex is poorly understood. We report a 46-year-old woman in whom this was assessed by intraoperative stimulation. This left-handed patient had a 30-year history of complex partial seizures with secondary generalization. Prolonged electroencephalographic recordings documented an epileptic focus in the right lateral and inferomesiotemporal lobe. Computed tomographic scanning and angiography suggested a right posterotemporal hamartoma. Amytal testing showed major speech representation in the right hemisphere. At craniotomy, an ivory-colored, posterotemporal lesion originating 5 cm from the temporal tip and 4 cm in diameter occupied the posterotemporal region. Electrical stimulation of this lesion produced speech interference. A histological examination of the resected anterotemporal lobe, amygdala, and hippocampus and biopsy specimens of the lesion showed extensive multifocal cortical microdysgenesis and gliovascular and cortical hamartoma. This case shows that grossly dysplastic cortex can remain functional. Cortical mapping under local anesthesia should be performed before resection of dysplastic lesions in putatively functional areas in patients with intractable epilepsy.

Amygdala↗
PubMed1994

Angiographic screening and elective surgery of familial cerebral aneurysms: a decision analysis.

Up to 6% of cerebral aneurysms may be familial. Because the pattern of inheritance and the prevalence of aneurysms within families are unknown, the management of family members at risk of harboring a cerebral aneurysm is currently empirical. We established the prevalence of aneurysms in the second generation of individuals with familial cerebral aneurysms and determined the possible benefit of angiographic screening and elective surgery of such individuals by using a simple decision analysis model. Four consecutive families were identified in whom the mother and a child had a ruptured cerebral aneurysm. A total of 19 siblings at risk in the second generation were identified. Fifteen underwent elective cerebral angiography: one had a cerebral aneurysm and two had an infundibulum at the origin of the posterior communicating artery. Including the previously known aneurysms, the prevalence of aneurysms in the second generation was thus established at 29.4%. A decision analysis was performed with 2% as the annual risk of rupture, 72.7% as the risk of death or disability with rupture, 0.1% as the risk of angiography, and 6.5% as the risk of surgery. The benefit in years of survival free of sequelae resulting from angiographic screening and elective surgery (intervention) over natural history was computed for life expectancy corresponding to each quinquennial age group from age 15 to 100 years. Intervention equaled natural history, in terms of years of survival expected with each choice, at a life expectancy of 10.6 years, corresponding to age 76.5 years for men and 80 years for women, and produced a net gain of at least 1 year for patients whose life expectancy was 32 years or more, corresponding to age 53.5 years for women and 49 years for men. Greater benefit was achieved with increasing life expectancy (younger age). The prevalence of aneurysms in the second generation when a mother and child have an aneurysm is 29.4%. Intervention produces a benefit of at least 1 year of survival free of sequelae over natural history in such individuals if their life expectancy is 32 years or more.

Adolescent↗
PubMed1994

Transcranial Doppler ultrasonographic changes after embolization of cerebral arteriovenous malformations.

The authors assessed the potential role of transcranial Doppler ultrasonography (US) in monitoring hemodynamic changes induced by embolization of cerebral arteriovenous malformations. Transcranial Doppler US was performed in eight patients with such lesions before and after embolization with n-butyl cyanoacrylate [corrected]. Changes in mean flow velocity and pulsatility index were analysed in all feeding and nonfeeding arteries. Anatomic and hemodynamic observations were also correlated with the results of digital subtraction angiography. A consistent trend was observed in all treated feeding arteries after embolization: the flow velocity decreased by a mean of 26% or 33 cm/s (p = 0.01, paired t-test), and the pulsatility index increased by a mean of 27% or 0.15 (p = 0.005). Although these changes did not correlate with the degree of angiographic reduction of the nidus (r = -0.31), they were most marked in malformations with a lower Spetzler grade or a higher degree of shunt obliteration. After embolization, recruitment of untreated feeding arteries was documented in two cases and a decrease in the "steal effect" from contralateral nonfeeding arteries in three. Changes in the nonfeeding arteries ipsilateral and contralateral to the malformation were variable. The authors conclude that transcranial Doppler US is a convenient and reliable method to evaluate quantitatively the hemodynamic effects of embolization of cerebral arteriovenous malformations.

Adult↗
PubMed1993

Preoperative embolization of brain and spinal hemangioblastomas.

Large hemangioblastomas can be difficult to resect because of excessive bleeding. We report our experience with two patients whose large hemangioblastomas were embolized preoperatively and were totally resected with minimal blood loss and satisfactory postoperative outcome. Embolizations were carried out within 3 days of surgery, with the patient under general anesthesia, with 150- to 250-microns Contour emboli. A 65-year-old woman with progressive, severe myelopathy from a 4.5 x 2.1 x 1.4 cm intramedullary hemangioblastoma at T4 underwent embolization of the left T2 and T3 intercostal arteries; a 29-year-old man with Lindau's syndrome and posterior fossa hemorrhage from a 3.8 x 1.8 x 1.8 cm right cerebellar hemangioblastoma underwent embolization of the right posterior inferior cerebellar artery, two right anterior inferior cerebellar arteries, and a dural branch of the right vertebral artery. Embolization led to the complete obliteration of the tumoral blush without neurological sequelae. Both lesions were completely resected with a blood loss of 50 to 100 ml, with bleeding occurring mainly from the pseudocapsule of the lesion. Preoperative embolization of hemangioblastomas is a useful and relatively safe procedure that reduces blood loss at the time of surgery and allows complete resection.

Adult↗
PubMed1993

Spinal angiolipomas. Report of three cases.

Spinal angiolipomas are distinct, benign lesions composed of mature lipocytes admixed with abnormal blood vessels. Three new cases of spinal angiolipoma are presented and 34 previously reported cases are analyzed. The 37 total cases (23 females and 14 males) ranged in age from 17 to 73 years (mean 43 years; median 45 years). The mean age of the female patients was older than that for the males (45.0 vs. 41.6 years; p < 0.001, Student's t-test) and most were peri- or postmenopausal. Prior to diagnosis, 97% of the patients had weakness of the lower extremities, 94% had sensory dysfunction, 84% had hyperreflexia and spasticity, 51% had sphincter dysfunction, and 41% had back pain lasting from 1 to 180 months (mean 28 months). Five (22%) of the 23 female patients were pregnant and two had exhibited significant weight gain coincident with the onset of symptoms. The angiolipomas were extradural in 35 patients and intramedullary in two; seven of the extradural lesions infiltrated the surrounding bone. The tumors extended from C-6 to L-4 and had a predilection for the midthoracic region (53% of cases). Plain radiographs were abnormal in 11 (39%) of 28 patients and in all patients with bone infiltration. Myelograms were abnormal in 97% of 32 patients and showed a complete block in 63% of patients. Computerized tomography (CT) and magnetic resonance (MR) imaging revealed the fat-density lesions in all cases studied. There was vascular enhancement in three of five cases with contrast-infused CT and in the one case with gadolinium-infused MR imaging. All patients improved following resection of the epidural lesions and internal decompression of the intramedullary lesions. It is concluded that spinal angiolipomas predominantly affect women. They involve the thoracic (especially the midthoracic) region, and produce symptoms and signs of spinal compression and, in some cases, bone erosion and pathological fractures. Their symptomatology can be exacerbated by pregnancy and weight gain, suggesting that vascular engorgement and the presence of obesity influence their evolution. Their preponderance in older, peri-, or postmenopausal women, and their clinical exacerbation in pregnant women support a role for hormonal influence. Magnetic resonance imaging is the investigation of choice for the diagnosis of these lesions. Surgery is universally successful in relieving symptoms.

Adult↗
PubMed1992

Giant aneurysm of the distal anterior cerebral artery: associated with an anterior communicating artery aneurysm and a dural arteriovenous fistula.

We describe an unusual case of a giant pericallosal artery aneurysm, producing psychomotor depression from mass effect, associated with a smaller aneurysm of the anterior communicating artery, a dural arteriovenous fistula, and a meningioma. Magnetic resonance imaging (MRI) and cerebral angiography demonstrated the giant aneurysm and the meningioma. Cerebral angiography provided a detailed appreciation of the cerebral circulation, including both aneurysms, the dural arteriovenous fistula, and the potential collateral supply to the involved anterior cerebral distribution. The anterior communicating artery aneurysm was successfully clipped as was the distal anterior cerebral branch supplying the giant aneurysm before its resection. The patient made a full recovery but with persisting, slight dysphasia. We conclude that computed tomography, cerebral angiography, and MRI are of specific value in the assessment of giant aneurysms, but only angiography can provide detailed characterization of the aneurysm and demonstrate other possible cerebrovascular pathology such as multiple aneurysms and arteriovenous fistulas.

Adult↗
PubMed1992

Language localization with activation positron emission tomography scanning.

We report the first instance of the use of 3-dimensional magnetic resonance imaging anatomically correlated to positron emission tomography (PET) scanning to identify language areas in a patient with an arteriovenous malformation (AVM) in the posterior speech region. The patient was a 24-year-old right-handed woman with an angiographically proven AVM (3-4 cm) in the left mid-posterior second temporal convolution in whom a left intracarotid injection of sodium Amytal produced significant language disruption. A baseline PET cerebral blood flow study identified the AVM, and an activation PET scan performed during the reading and speaking of simple words showed increased activity in the left parastriate cortex (the second visual area), in the left posterior third frontal convolution (Broca's area), and in the left inferior and midtemporal gyri (Wernicke's area). Increased activity was also noted in the right and left transverse temporal (Heschl's) gyri, in the left precentral gyrus, in the left medial superior frontal gyrus (the supplementary motor area), and in the right cerebellum. We conclude that activation PET scanning is useful in the preoperative assessment of patients who harbor cerebral AVMs in classically described speech regions.

Adult↗
PubMed1992

Cerebral hemorrhage from amyloid angiopathy and coronary thrombolysis.

Coronary thrombolysis with streptokinase or tissue plasminogen activator is useful for the treatment of acute myocardial infarction in selected patients. This treatment is associated with local hemorrhagic complications and age-related cerebral hemorrhage. Coronary thrombolysis is contraindicated in patients with transient cerebral ischemia and stroke, arterial hypertension, cerebral trauma, cerebral aneurysms, and arteriovenous malformations, because of the risk of cerebral hemorrhage. We report the occurrence of a cerebral hemorrhage related to cerebral amyloid angiopathy in a patient who underwent thrombolysis and treatment with heparin for acute myocardial infarction. Despite normal coagulation parameters, the cerebral hematoma enlarged over 36 hours, as documented by sequential computed tomographic scans, to produce significant mass effect, which prompted surgical evacuation. Histological examination of the resected specimen demonstrated the strong affinity for Congo red and yellow-green birefringence that are characteristic of cerebral amyloid angiopathy. Hemostasis was difficult to achieve, as the divided or disrupted amyloid-laden cortical vessels failed to vasoconstrict, their contractile elements replaced by amyloid beta protein. The patient died of recurrent myocardial ischemia 3 days postoperatively. The incidence of cerebral amyloid angiopathy increases with advancing age. It must be considered as a potential source of cerebral hemorrhage in elderly patients undergoing thrombolysis for cardiac ischemia. Such an occurrence presents a difficult challenge because cardiac function is compromised, the coagulation profile may be altered, the cerebral hematoma is life threatening, and intracranial hemostasis is difficult to achieve.

Aged↗