Ex vivo study of dentate gyrus neurogenesis in human pharmacoresistant temporal lobe epilepsy.

AIMS: Neurogenesis in adult humans occurs in at least two areas of the brain, the subventricular zone of the telencephalon and the subgranular layer of the dentate gyrus in the hippocampal formation. We studied dentate gyrus subgranular layer neurogenesis in patients subjected to tailored antero-mesial temporal resection including amygdalohippocampectomy due to pharmacoresistant temporal lobe epilepsy (TLE) using the in vitro neurosphere assay. METHODS: Sixteen patients were enrolled in the study; mesial temporal sclerosis (MTS) was present in eight patients. Neurogenesis was investigated by ex vivo neurosphere expansion in the presence of mitogens (epidermal growth factor + basic fibroblast growth factor) and spontaneous differentiation after mitogen withdrawal. Growth factor synthesis was investigated by qRT-PCR in neurospheres. RESULTS: We demonstrate that in vitro proliferation of cells derived from dentate gyrus of TLE patients is dependent on disease duration. Moreover, the presence of MTS impairs proliferation. As long as in vitro proliferation occurs, neurogenesis is maintained, and cells expressing a mature neurone phenotype (TuJ1, MAP2, GAD) are spontaneously formed after mitogen withdrawal. Finally, formed neurospheres express mRNAs encoding for growth (vascular endothelial growth factor) as well as neurotrophic factors (brain-derived neurotrophic factor, ciliary neurotrophic factor, glial-derived neurotrophic factor, nerve growth factor). CONCLUSION: We demonstrated that residual neurogenesis in the subgranular layer of the dentate gyrus in TLE is dependent on diseases duration and absent in MTS.

Ulnar neuropathy due to a carpal ganglion: the diagnostic contribution of CT.

Clinical features and electrophysiologic studies indicated a lesion of the ulnar nerve in the wrist of a 50-year-old man. CT of this region revealed a ganglion inside Guyon's canal. Surgical exploration disclosed a carpal ganglion compressing the ulnar nerve just proximal to its division.

Spontaneous healing of extradural hematomas: report of four cases.

Our recent experience with four cases of acute extradural hematoma found in neurologically intact or mildly symptomatic patients is reported. These patients did not require operation; complete resolution of the hematoma was demonstrated within 1 month in three cases and within 4 months in the last case. Although far from being codified, nonsurgical treatment of extradural hematomas in some selected patients seems to be feasible. The computed tomographic findings (size and location of the hematoma, midline shift) in these cases are discussed.

Spontaneous healing of acute extradural hematomas: study of twenty-two cases.

A series of 22 patients with acute extradural hematomas that were not evacuated surgically is presented. Patients were asymptomatic or had only minimal neurological disturbances on admission. In all cases, serial computed tomographic scanning documented the progressive resolution of these clots, the great majority within 1 month of injury. The decision of conservative vs. surgical treatment may be guided by the thickness, configuration, location, and possible association with intradural parenchymal lesion.

Acute bilateral extradural hematomas in a case of osteogenesis imperfecta congenita.

Acute bilateral extradural hematomas occurred after apparently trivial trauma in a patient suffering from osteogenesis imperfecta congenita. Factors influencing the development of this dramatic complication are peculiar to this rare disorder of bone and connective tissue development and include bony weakness, increased vascular fragility, and possible coagulopathies.

Spinal extrathecal hemangiolipomas: report of two cases and review of the literature.

Two cases of a rare entity, spinal extrathecal hemangiolipoma, are presented. The clinical and histological features of the tumor are discussed, with particular attention to the uncommonly sudden onset of symptoms in one patient. Complete neurological recovery was exhibited by one patient after excision of the lesion, whereas only a partial recovery was achieved in the other case. The pathogenetic aspects of hemangiolipomas and the literature dealing with the previously reported 12 cases are reviewed.

Benign traumatic intracerebellar hematoma.

Prompt surgical intervention is thought to be necessary in patients with traumatic intracerebellar hematoma. The case reported here ran a benign course without operation. Pertinent serial computed tomographic scans are presented. It is concluded that not all traumatic hematomas of the cerebellum require operations.

Dissecting aneurysms of the basilar artery.

Ten patients (six men and four women; mean age, 40 yr) with spontaneous dissection of the basilar artery are reported. Clinically, six were admitted with subarachnoid hemorrhage (SAH) and four were admitted with brain stem ischemia. Angiography demonstrated string sign in four patients, pearl reaction in four, double lumen in one, and arterial ectasia with mural retention of contrast medium in one. Magnetic resonance imaging was performed in two patients. Follow-up angiograms or magnetic resonance angiography in six patients showed spontaneous healing in two patients, improvement in two, progression in one, and no change in one. Nine patients were treated medically, and one underwent selective intravascular occlusion of the dissecting aneurysm. One patient died after further SAH, two remain severely disabled, three have residual neurological deficit, and four are in good clinical condition. The most interesting observations in this series include a relatively good course in a substantial number of patients and low further bleeding potential after SAH, the late "globular" evolution, which may be favorable for reconstructive treatment, and the diagnostic value of associated computed tomographic/angiographic findings. Surgical options in basilar dissection are very poor; in some reported cases, wrapping has been tried with disappointing results. In light of the possibility of spontaneous healing or improvement, wrapping should be reserved for only those patients with recurrent SAH or angiographic progression of the dissection.

The growth of cerebral cavernous angiomas.

The natural history of cavernous angiomas is poorly understood, and their growth has rarely been documented. We report three cases of cavernous angiomas that grew to large size in 6 years, 2 years, and 2 months, respectively. An initial computed tomographic scan disclosed no abnormalities in one patient and demonstrated two "minimal" lesions in the other two. The mechanisms of growth of these lesions are discussed; subsequent hemorrhages and capsule formation played a major role in their enlargement.

Facial nerve palsy secondary to a dural cavernous angioma of the middle cranial fossa eroding the tegmen tympani.

A patient with a dural cavernous angioma of the middle cranial fossa eroding the tegmen tympani and causing an isolated palsy of the facial nerve is presented. The rarity of this lesion is stressed, as are the peculiar clinical findings and the magnetic resonance imaging.

Occult cerebrovascular malformations after irradiation.

OBJECTIVE: It has recently been found that patients receiving cerebral irradiation can develop hemorrhagic dysangiogeneses simulating occult vascular malformations. To analyze this connection, we report on five patients with occult cerebrovascular malformations occurring after "standard" or focused irradiation performed for brain tumors in four patients and for a deep-seated cavernous angioma in one patient. METHODS: All lesions were within the radiation ports. The time interval between irradiation and the detection of the occult vascular malformations varied from 3 to 9 years; the ratio of female to male patients was 4:1. Four patients were < 15 years old when first irradiated. Four patients presented with acute symptoms (headache, vomiting, focal signs) and one was asymptomatic when the lesions were first detected. Serial magnetic resonance imaging scans were available in four patients and a computed tomographic scan in the other patient. RESULTS: The initial appearance was that of a hypointense T1-T2 focus; magnetic resonance imaging then revealed focal or multifocal T1 hyperintensity and T2 mixed signal intensity followed by a late ring of decreased signal intensity. Four patients were operated on and one was under neuroradiological monitoring. Histological features of these lesions included clusters of closely packed vascular spaces resembling cavernous malformations sometimes associated with a thrombosed thick-walled vein with intense hemosiderin deposition and fibroblastic proliferation; telangiectasic changes were also seen in the adjacent brain. CONCLUSION: Increased awareness of occult cerebrovascular malformations is necessary, because their occurrence is not infrequent and they have hemorrhagic potential. Children receiving cerebral irradiation are at greater risk of this complication.

Pituitary apoplexy, bilateral carotid vasospasm, and cerebral infarction in a 15-year-old boy.

The authors report a case of pituitary apoplexy associated with oculomotor defects and focal cerebral signs; the visual pathways were intact. Computed tomography documented a mass of heterogeneous density within an enlarged sella turcica and a right parietal infarct. Angiograms revealed bilateral carotid spasm and occlusion of the right angular artery. Treatment was conservative. Control angiograms showed spontaneous resolution of the vasospasm and recanalization of the cortical artery. The patient made a complete neurological recovery; he needed only treatment with vasopressin due to transient diabetes insipidus. The risk of vasospasm and brain ischemia should be kept in mind when treating pituitary apoplexy. The early occurrence of vasospasm in our case suggests the participation of powerful vasoactive agents liberated from the tumor.

Growth, subsequent bleeding, and de novo appearance of cerebral cavernous angiomas.

In a series of 145 patients with brain cavernous angiomas treated at our hospital in the last 16 years, the angiomas of 18 patients exhibited aggressive biological behavior characterized by recurrent overt bleeding, growth, or de novo appearance. The cavernomas were in the cerebellum in three patients, in the brain stem in one, in the thalamus in four, in the caudate nucleus in two, in the diencephalon in one, and in the white matter of the cerebral hemispheres in seven. Three of these patients suffered from the familial or multiple form of the disease, two were pregnant, three had previously been irradiated for other tumors, and one had been treated by radiosurgery in the past. Overall, new cavernous malformations not previously shown were discovered in six patients. In 10 patients (3 male and 7 female) presenting with recurrent hemorrhages, the mean period of time between bleedings was 11 months (range, 1 wk-3 yr). Eleven patients were treated by definitive surgery, and seven were conservatively treated. One patient with a diencephalic cavernoma died from progressive hypothalamic dysfunction; three patients in the nonsurgical group had repeated symptoms and were left with additional neurological deficits. The outcome of the surgical group was the same (seven patients) or improved (four patients). Risk factors favoring an aggressive behavior included pregnancy, familial or multiple form of the disease, previous whole brain or stereotactic radiotherapy, incomplete removal, brain location, and associated venous malformation. The female preponderance (female to male ratio, 13:5) may also suggest some role of hormonal factors in influencing the biological behavior of cavernous malformations.

Traumatic intracerebellar hematomas.

Seven patients with "isolated" traumatic intracerebellar hematomas due to closed head injuries are presented. Computerized tomography parameters useful in the correct management of these hematomas include: location (hemisphere or midline), size, and appearance of the posterior fossa cisterns (intact or obliterated). Three patients with hemispheric hematomas were treated conservatively and recovered. One patient with a midline hematoma was managed conservatively and died. Three hematomas (one hemispheric and two midline) were operated on. The immediate results of surgery were good, but two patients died later due to medical complications. The results of this study support the concept that large hematomas (3 cm or greater) generally need surgery and that hemispheric hematomas of limited size (less than 3 cm) may be treated conservatively. The clinical course of prognosis of midline hematomas is grave, and evacuation of accessible hematomas should be considered early in the course of the disease.

Traumatic aneurysms of the supraclinoid internal carotid artery.

This paper describes two patients with traumatic aneurysms of the supraclinoid internal carotid artery, which occurred after a closed-head injury and without demonstrable basal skull fracture. In the first case, the traumatic origin of the aneurysm was demonstrated by repeat angiograms. The second case documents the formation of a giant, traumatic, true aneurysm of the supraclinoid carotid artery over a period of less than 2 months; there was an associated traumatic partial occlusion of the vessel proximal to the aneurysm. The mechanisms of injury of the supraclinoid carotid artery are discussed.

Giant aneurysm of the pericallosal artery. Case report.

A case is reported of a thrombosed giant aneurysm of the pericallosal artery. Neurological presentation was attributable to the acute swelling of the aneurysmal mass after rapid and massive intraluminal thrombosis. This case demonstrates that initial symptoms in giant aneurysms may be related to the thrombotic events within the enlarged sac. The computerized tomography characteristics of this case are reported and discussed.

Resolution of occlusion in spontaneously dissected carotid arteries. Report of two cases.

Two cases of internal carotid artery occlusion secondary to spontaneous dissection are reported. Both patients presented with transient ischemic attacks. both had antiplatelet aggregation therapy, followed by spontaneous resolution of the occlusion. The period of healing seems to be relatively short. In both cases, restoration of flow was angiographically documented 14 days and 10 weeks after the initial arteriogram. Strategies for treatment of such patients are discussed.

Leptomeningeal angiomatosis and aplasia congenita of the scalp. Case report.

This 9-year-old boy had two circular areas of aplasia congenita of the scalp in the territory of the first division of the trigeminal nerve and an ipsilateral parieto-occipital leptomeningeal capillary venous angioma. He had an associated giant aneurysm of the distal posterior cerebral artery on the same side as the vascular malformation. The patient had a long history of seizures and presented with intracerebral bleeding. This case may be considered as a variant of Sturge-Weber syndrome. Further observations must be added to consider this entity as a separate neurocutaneous disease.

Cerebral aspergillosis following intracranial surgery. Case report.

The authors report a case of cerebral aspergillosis. This is only the fifth case following intracranial surgery noted in the literature. Pathogenesis, angiographic findings, and results of cerebrospinal fluid culture are discussed.

Benign arterial dissections of the posterior circulation.

Four young adults with spontaneous dissection of the vertebrobasilar system are reported. Clinically, two patients presented with subarachnoid hemorrhage and two with brain-stem ischemia. In two cases of ruptured arterial dissection of the posterior cerebral artery, angiography demonstrated fusiform and "sausage-like" dilatation of the involved vessel. In two cases of occlusive dissection of the basilar artery, angiography revealed the typical "string sign." All four patients were treated conservatively: three survive in good clinical condition and one remains disabled. Follow-up angiograms showed spontaneous healing of the lesion with return to an almost normal arterial configuration in two cases; residual narrowing corresponding to the dissection was the most notable finding in the other two. It is recommended that, in a subset of neurologically stable patients, angiographic monitoring is undertaken to assess the tendency for spontaneous repair before surgical intervention is planned.