Nonhistological diagnosis of human cerebral tumors by 1H magnetic resonance spectroscopy and amino acid analysis.

We describe a multivariate analysis procedure to classify human cerebral tumors nonhistologically in vitro, combining the use of 1H magnetic resonance spectroscopy (MRS) with automatic amino acid analysis of biopsy extracts. Eighty-one biopsies were obtained surgically and classified histologically in eight classes: high-grade astrocytomas (class 1, n = 19), low-grade astrocytomas (class 2, n = 10), normal brain (class 3, n = 9), medulloblastomas (class 4, n = 4), meningiomas (class 5, n = 18), metastases (class 6, n = 8), neurinomas (class 7, n = 9), and oligodendrogliomas (class 8, n = 4). Perchloric acid extracts were prepared from every biopsy and analyzed by high resolution 1H MRS and automatic amino acid analysis by ionic exchange chromatography. Intensities of 27 resonances and ratios of resonances were measured in the 1H MRS spectra, and 17 amino acid concentrations were determined in the chromatograms. Linear discriminant analysis provided the most adequate combination of these variables for binary classifications of a biopsy between any two possible classes and in multiple choice comparisons, involving the eight possible classes considered. Correct diagnosis was obtained when the class selected by the computer matched the histological diagnosis. In binary comparisons, consideration of the amino acid profile increased the percentage of correct classifications, being always higher than 75% and reaching 100% in many cases. In multilateral comparisons, scores were: high-grade astrocytomas, 80%; low-grade astrocytomas, 74%; normal brain, 100%; medulloblastomas, 100%; meningiomas, 94.5%; metastases, 86%; neurinomas, 100%; and oligodendrogliomas, 75%. These results indicate that statistical multivariate procedures, combining 1H MRS and amino acid analysis of tissue extracts, provide a valuable classifier for the nonhistological diagnosis of biopsies from brain tumors in vitro.

Percutaneous vertebroplasty: a special syringe for cement injection.

Percutaneous vertebroplasty is an effective treatment for many focal vertebral lesions. Methyl methacrylate is too viscous to be handled without difficulty in the conventional way because injection time is short. The operator is left with little time and must fumble with multiple syringes. We describe a special screw-system syringe that decreases the effort needed to inject the cement. In addition, it can standardize the injection pressures and control the injected volume because the threaded plunger affords greater control of injection pressure and volume delivered than does the conventional method.

Encapsulated intracerebral hematomas: a defined entity. Case report.

Encapsulated intracerebral hematoma is an interesting and not widely appreciated entity. It can be defined as an intraparenchymal hematoma found in normotensive patients, usually caused by histologically confirmed vascular malformations, characterized by a gradual clinical onset, and presenting a well-defined capsule at operation. One case is presented and 25 previously reported cases are reviewed, all reflecting the above-mentioned characteristics. The hematomas reviewed here occurred in relatively young patients with a mean age of 35 years and a clear male predominance (19 males, seven females). A ring of contrast enhancement around a lesion of variable density, usually with mass effect and perifocal edema, is the most relevant feature on computerized tomography. Findings on magnetic resonance images are described for the first time in the reported case. A vascular malformation was the most frequent cause found on histological examination (12 of the 26 total cases). No proven cause was found in the remaining 14 cases, although a small vascular malformation, destroyed or thrombosed after rupturing and bleeding, is the most likely etiology in these patients.

Neural migration disorders studied by cerebral ultrasound and colour Doppler flow imaging.

Cerebral ultrasound and colour Doppler flow imaging (CDFI) were used to diagnose a wide spectrum of anomalies of cell migration (17 patients): presumed lissencephaly (n = 12); schizencephaly of both fused (n = 2) and open lips (n = 2); hemimegalencephaly (n = 1); and subependymal type grey matter heterotopia (n = 12). The patients with grey matter heterotopia had irregular ventricular margins (n = 10), periventricular hyperechogenic bands (n = 12), and/or periventricular hyperechogenic nodules (n = 7). Some patients had more than one type of migration disorder as well as other central nervous system malformations. Cerebral ultrasound diagnoses were confirmed by magnetic resonance imaging (MRI) or necropsy. It is concluded that colour Doppler flow imaging is a worthwhile addition to the assessment of brain surface anomalies.

Is cerebral arteritis the cause of the Landau-Kleffner syndrome? Four cases in childhood with angiographic study.

Four children with Landau-Kleffner syndrome were studied over a six year period. They presented with acquired aphasia, epilepsy, and focal or generalized EEG discharges which were exacerbated during sleep. In addition, cerebral angiography demonstrated isolated arteritis of some branches of the carotid arteries in all cases. Computed tomographic and magnetic resonance images were normal. Nicardipine in a dose of 1 to 2 mg/kg/day, added to conventional anticonvulsant drugs provided effective supplementary control of seizures, of paroxysmal EEG discharges, and of language and behavioural disturbances, even several years after the onset of the disorder and in patients whose response to other medications, including steroids, had been poor. Interruption of nicardipine administration was followed by relapse of the language disorder. Repeat angiography was performed in all four patients and showed recanalization of obstructed vessels in two cases. Focal cerebral vasculitis may be the pathogenesis of the Landau-Kleffner syndrome and calcium channel blockers such as nicardipine may be effective and specific therapy.

Stroke in neonates with cardiac right-to-left shunt.

Neonatal focal cerebral arterial infarction has been rarely reported in the literature, in contrast to the watershed infarctions, which are common entities among asphyxiated infants. In neonatal postmortem series, thromboembolism was the commonest cause of cerebral arterial occlusion; the source of emboli was associated to different risk factors. Our four cases are the first alive patients reported with congenital heart disease and right-to-left shunt, who suffered a cerebral infarct with its clinical neurological correlates in the neonatal period. We assume that the most probable mechanism was paradoxical embolism, once pulmonary filter is obviated as a result of the altered hemodynamics in these patients. Our data demonstrate the value of ultrasound scanning for assessment of focal cerebral ischemic lesions. Thus, although abnormal neurological signs in this particular group of infants could be attributed to hypoxemia or specific treatments as prostaglandins, we suggest routine cerebral ultrasounds in neonates with congenital heart disease and neurological disabilities, as early complications could be not so infrequent.

Early infantile epileptic encephalopathy: a case associated with hemimegalencephaly.

The authors report a case of early infantile epileptic encephalopathy (EIEE) associated with hemimegalencephaly. The etiological factors in previously published cases of EIEE are reviewed and attention is focused on the high proportion of cases associated with neuronal migration disorders. We suggest that idiopathic cases of EIEE would be due to such disorders.

Moyamoya disease with a marked collateral supply through the artery of Bernasconi-Cassinari.

A case of moyamoya disease is presented. The patient is a 15-year-old white Spanish girl who had the onset of the neurological symptoms at 8 months of age with seizures, transient ischemic attacks and residual left hemiparesis. Cerebral arteriography performed at the age of 1 year revealed all the features of moyamoya disease in the territory of both carotids and in the vertebrobasilar arteries. The presence of an embryonic tentorial artery, the Bernasconi-Cassinari artery, originating from the right internal carotid artery, was disclosed at 1 year of age but did not appear in an arteriogram performed at 6 years of age and it was revisualized by magnetic resonance arteriography (MRA) performed at the age of 15 years. This finding seems to indicate a very early intrauterine onset of the disease in this case and demonstrates the superiority of MRA over conventional arteriography to discover anomalies of intracranial vessels. Administration of nicardipine, a calcium channel blocker, added to conventional antiepileptic drugs that the patient had previously taken, improved the epileptic and the neurological disease.

Ultrasonographic findings in thalamus and basal ganglia in term asphyxiated infants.

Three severely asphyxiated term neonates demonstrated bilateral hyperechogenicity in the thalamus and basal ganglia. During evolution, areas of attenuated echogenicity appeared in these structures at the same time as periventricular cysts were evident in 2 patients with coexistent periventricular leukomalacia. All 3 patients developed ventricular dilatation; in the 2 patients with periventricular leukomalacia, the ventricular border was irregular in the outer (dorsal) margin, and interhemispheric fissures were widened as a manifestation of cerebral atrophy. Furthermore, the thalamic inner (ventral) margins of the lateral ventricles were irregular in all 3 patients. This previously unrecognized finding points to a particular form of cerebral atrophy localized in the gangliothalamic region that contributes to the development of ventriculomegaly. The reported sonographic sequence implies profound damage in the thalamus and basal ganglia in asphyxiated infants which undoubtedly has contributed to the poor outcomes of our patients.

Supratentorial neuroepithelial cysts. Report of two cases.

The paper reports two cases of supratentorial neuroepithelial cysts, also called ependymal cysts. One of them was extracerebral and the other intracerebral. The preoperative diagnosis was made by determination of attenuation values of consecutive sections of cyst on computed tomography. The ultrastructure of the cyst wall was studied in one case. Other problems dealing with these rare lesions are discussed.

Pineal region meningiomas without dural attachment.

A rare case of meningioma in the pineal region without dural attachment, which was successfully removed through an infratentorial supracerebellar approach, is presented. The preoperative diagnosis was made by means of computed tomography together with histographic analysis. We review similar cases reported in the literature and discuss the clinical feature, diagnostic aspects, and surgical management.

Posterior fossa epidural hematomas: a review and synthesis.

The authors report three patients with posterior fossa epidural hematomas and analyze 80 additional cases in the accessible literature. They occur in the younger age groups with a clear male predominance (3.6 to 1). The loss of consciousness at the time of impact and just before surgical intervention have both proved to be factors indicating a poor prognosis. The clinical symptoms and signs were classified in three general types: increased intracranial pressure, brainstem dysfunction, and cerebellar disturbances. A fracture of the occipital bone was seen in 84.2% of the patients. The source of bleeding often remained undetermined, although a tear of the dural sinuses was a most frequent finding. An associated intracranial lesion was found in 39.7% of the cases, this being another factor indicating a poor prognosis. The overall mortality was 26.5%, while the surgical mortality was only 11.5%. Excellent results were achieved in 65% of the cases.

Hydatid cyst: unusual cause of unilateral exophthalmos.

Intraorbital hydatid cysts are encountered unusually on neurosurgical services. Recently, 3 patients with intraorbital hydatid cysts have been studied by the Neurosurgical Service of C. S. "La Paz." In two of them, a computed tomography (CT) scan was performed; we think that these are the first cases of this type to be studied with CT scans. In each case, the CT scan showed a circular mass with a density similar to that of the eye. Frequency, localization, symptomatology, and neuroradiological aspects of intraorbital hydatid cysts are described. The different surgical approaches also are discussed.

Giant vascular malformation of the face in a premature infant: complete resolution by embolization.

The authors report on a neonate who had a large vascular malformation affecting the eye, maxilla, and mandible. This was managed successfully with percutaneous embolization.

Gene therapy in brain tumours: implications of the size of glioblastoma on its curability.

The authors have used the thymidine kinase/ganciclovir system to block glioblastoma multiforme neoplastic cells in vivo, both in experimental animals and in two patients in which the more conventional therapies had been unsuccessful. In the Wistar rat it was found that the curability potential of the system is correlated with tumoral volume. Tumours smaller than 20 mm3 can be cured with defective retrovirus that do not carry the Herpes simplex thymidine kinase (Hsvtk) gene. While tumours smaller than 150 mm3 can regress totally by the kinase/ganciclovir system, those above that size cannot be cured by this treatment. In humans the situation seems very similar in that the authors have been unable either to reduce the tumour size of recurrent patients with tumour volumes larger than 100 cm2 applying the standard thymidine kinase/ganciclovir gene therapy or to prolong their survival time more than 8 months [7]. When a combination of size reduction by neurosurgery and gene therapy was used the survival time increased considerably. Two patients have been treated by partial surgery and repeated treatment with thymidine kinase/ganciclovir through an Ommaya reservoir connected to a catheter leading into the tumour cavity. The magnetic resonance imaging (MRI) of these patients show only a residual tumoral growth along side the tumoral bed. The procedure may be partially controlling the proliferation of cancerous cells, because, these two patients having recurrent glioblastoma, are alive 11 and 17 months after the beginning of the treatment.

[Arteriovenous malformations of the vein of Galen]. / Malformación arteriovenosa de la vena de Galeno.

Vein of Galen arteriovenous malformations encompass a diverse group of vascular anomalies that share a common feature: dilatation of the vein of Galen. Although clinical presentations are highly variable, depending on age of presentation, signs and symptoms overlap between age groups. The association of heart failure and cranial bruit constitutes the most striking clinical presentation in neonates. However, less severe and fulminant modes of presentation are frequent in older infants, children, and adults. Treatment approaches consist of symptomatic treatment of heart failure on the one hand and of surgery or endovascular treatment on the other. The results of the latter have improved in recent years, opening up a broad spectrum of new possibilities. We present the case of an asymptomatic 15-day-old neonate who presented an arteriovenous malformation of the vein of Galen and who was treated with endovascular occlusion of the arterial afferents. An excellent result was obtained with no evidence of neurological abnormalities.

[Partial splenic embolization in the treatment of hypersplenism. Long-term results]. / Embolización parcial esplénica en el tratamiento del hiperesplenismo. Resultados a largo plazo.

In order to assess long term evolution of partial splenic embolization (PSE), 21 patients with hypersplenism treated by this technique from January 1984 to December 1992 have been reviewed. Between 50 and 90% of the splenic parenchyma was embolized in these patients. The follow-up period ranged between 12 and 103 months (mean = 32 months). Remaining splenic tissue was evaluated through sequential hematologic, ultrasonic and gammagraphic studies. After one year post-embolization white blood cells and platelets showed normal values. Five years later the mean values for these two parameters was lower but within the normal range. The mean reduction of splenic mass as estimated by ultrasound and gamma graphic studies was of 40% at one year and 17% at five years. Our results show that SPE can control hypersplenism, specially during the first years, but there is a tendency to a decrease in the leucocyte and platelet counts after five years. A regeneration of the splenic mass occurs in the long run after embolization. In our patients a relation between splenic regeneration and hypersplenism could not be demonstrated.

Intracranial perianeurysmal cyst: still a dilemma. A case report with endovascular management.

Intracranial perianeurysmal cysts constitute an extremely rare entity with very few cases reported in the literature. These cysts present an unknown mechanism of formation and clinical significance. Several theories based on isolated cases have been proposed, without drawing a clear conclusion. It is also unknown if follow-up with imaging techniques is required or which is the most appropriate treatment. We describe an atypical case handled with a satisfactory outcome after endovascular treatment, suggesting the importance of hydrodynamic forces as the key factors in the mechanism of formation. We believe that this case can help in future analysis of this rare entity.