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.

Endovascular Treatment of Cerebral AVM: Our Experience with Onyx.

SUMMARY: We have been using Onyx, a non-adhesive liquid polymer, to treat cerebral AVMs endovascularly since 1999. During this time we have treated 45 consecutive, unselected patients. From the outset this product brought about a change in our approach to treating this type of lesion because of the different injection behaviour observed for this material compared with the adhesive Histoacryl that had been employed until then. The object of this article is to assess the results achieved by our team using this new embolic agent, following angiographic and clinical follow- up of cases for a minimum of six months and a maximum of five years (mean: two years). We propose new categories of cerebral AVM based on the expected behaviour of Onyx within the nidus. Our appraisal indicates that we have improved our angiographic results, achieving complete occlusion of the malformation in 22% of cases and over 80-% closure in 69% of cases. The morbimortality rate for the procedure was 18%.

[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.

Vertebroplasty in the treatment of vertebral tumors: postprocedural outcome and quality of life.

The results of percutaneous vertebroplasty with polymethylmethacrylate (PMMA) of vertebral metastases were evaluated by a retrospective review of a consecutive series of 21 patients, with special reference to functional outcome. Patients complained of vertebral pain in all cases. Walking was impossible for 13 patients. Ten patients presented neurological deficit. Treatment included percutaneous vertebroplasty in all patients, radiotherapy in 15 patients and neural decompression surgery in 3 patients. Mean duration of hospitalization was 14.1 days (range 2-60 days) and the mean follow-up was 5.6 months (range 1-18 months). Preprocedural pain, measured by the visual analog scale (VAS), was 9.1, decreasing to 3.2 after the procedure and 2.8 at the last follow-up visit. Morphinics were discontinued in 7 of 14 patients following discharge from hospital. Ten out of 13 (77%) patients recovered walking capacity. Neurological status improved in three out of five patients. No further vertebral compression occurred in the vertebrae treated. Overall, 81% of the patients in this study were satisfied or very satisfied with the procedure. One patient (5%) had transitory radicular neuritis after the procedure. No major complications were observed. In conclusion, percutaneous vertebroplasty with PMMA proved to be safe and beneficial, providing significant and early improvement in the functional status of patients with spinal metastasis.

Percutaneous vertebroplasty: long-term clinical and radiological outcome.

We assessed radiographic and functional outcome in 13 patients with a minimum of 5 years follow-up from a prospectively monitored series of 17 patients who underwent percutaneous vertebroplasty (PPV). A visual analogue scale (VAS) and the short McGill questionnaire (MPQ) were used to assess average symptoms. The VAS showed significant improvement after treatment: the initial score was 9.07+/-0.6 (mean+/-SD), falling to 2.07 (1.14) on the third day, 1.07 (1.07) by the third month and 2.15 (2.6) at 5 years. Pain reduction was statistically significant ( P<0.001). The MPQ showed a significant improvement after treatment ( P<0.001), but had worsened by the last follow-up. All patients were "very" or "somewhat satisfied" with the procedure. We saw no further collapse of the vertebrae injected or migration or changes in the shape of the cement. A new fracture was seen in three patients, affecting four vertebrae, only two of which were adjacent to the treated level. On CT following the procedure, there was cement in the epidural veins adjacent to the vertebra in 48% of cases, but only patient developed a transitory neuritis.

Moyamoya disease and sagittal sinus thrombosis in a child with Down's syndrome.

A girl with Down's syndrome, moyamoya disease and sagittal sinus thrombosis is described. She was diagnosed after acute neurological deterioration by MRI and angiography. Recombinant tissue plasminogen activator (r-TPA) was injected locally to recanalise the thrombus. The patient's condition significantly improved and she was discharged. After 2 years of follow-up the child remains asymptomatic. Moyamoya syndrome and cerebral venous thrombosis should not be overlooked as a cause of acute neurological deterioration in a child with Down's syndrome. MRA appears to be a safe and accurate alternative to traditional angiography for the diagnosis of moyamoya disease. Local fibrinolysis with r-TPA is the treatment of choice for cerebral venous thrombosis due to its safety and efficacy.

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.

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.

Human malignant brain tumor response to herpes simplex thymidine kinase (HSVtk)/ganciclovir gene therapy.

Growing cells from human brain tumors have been treated in vitro and in vivo with murine therapeutic retroviral producer cells. The therapeutic retrovirus carried the potential suicide gene thymidine kinase (tk) from the herpes simplex virus (HSV). After a few days, in which a large proportion of the tumoral cells had the opportunity to acquire a copy of the retrovirus, treatment with ganciclovir was initiated and considered responsible for considerable cell death both in vitro and in vivo. The in vivo experiments were performed in five adult patients who had failed standard therapy and were expected to survive only a few weeks.

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.

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.

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.

Long-term rat survival after malignant brain tumor regression by retroviral gene therapy.

Total regression of malignant brain tumors was observed in Wistar rats after retrovirus-mediated gene therapy. Tumors were induced by inoculation of C6 rat glioblastoma cells to a specific location in the rat brain and the tumors that developed were visualized by magnetic resonance imaging (MR). Retroviral vectors were constructed from a defective murine retrovirus to which the thymidine kinase (tk 1) gene from herpes simplex was added (HSV1tk). The vectors produced therapeutic viruses upon their introduction into retrovirus packaging cells. Delivery of the producer cells to the tumor mass and subsequent antiherpetic treatment eradicated the tumors completely, as observed using MRI. Some of the treated animals have been followed for over 8 months and show no signs of recurrence.

[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.