0000000000047003
AUTHOR
J. L. Barcia-salorio
Histologic and Cytogenetic Patterns in Benign, Atypical, and Malignant Meningiomas
Atypical meningiomas comprise an intermediate category of meningeal neoplasmas with some microscopic features of aggressivity and a capacity for recurrence. We present a clin ical, morphologic, and cytogenetic study of 15 meningiomas. Morphologic and cytogenetic analysis suggested the existence of morphologically typical meningiomas with normal karyotype or monosomy 22 and morphologically atypical meningiomas, with increasing chromosomal abnormalities (complex karyotype) between these two types. Present results suggest the existence of a third type of morphologically typical meningioma that lacks a phenotypical aggressivity but has a complex karyotype. These genotypical characteristics may…
Involvement of the long arm of chromosome 9 in medulloblastoma in an adult.
Abstract Medulloblastoma is the most common primitive neuroectodermal tumor (PNET) in children, but is very rare in adults. An isochromosome for the long arms of 17, i(17q), is found in about 30% of pediatric cases. Cytogenetic studies in adults are very scarce; only six cases have been described cytogenetically: three cases had normal karyotype, two were studied partially, and another presented only two clonal structural anomalies: del(9)(q12) and del(11)(q22). We studied the chromosomes from medulloblastoma in a 27-year-old woman and found one hypotetraploid stemline with clonal alterations. In the structural anomalies, chromosomes 3, 9, 12, and i(17q) were involved. Chromosome 9 presente…
Radiosurgical Treatment of low flow Carotid-Cavernous Fistulae
The good results obtained by stereotactic radiosurgery in arteriovenous malformations has led the authors to expect similar results in low flow carotid-cavernous fistulae. In this paper, 20 cases who underwent radiosurgery with a conventional gamma source are presented. The total dose delivered was 36 to 40 Gy. 90% of the patients were cured after radiosurgery after a mean time of 7 months. Those presenting a mild improvement after a mean time of 2 months and those with a marked improvement after 4 months.
Stereotactic Radiosurgery of Deeply Seated Low Grade Gliomas
The authors report the results of a series of 16 cases of low-grade gliomas in whom radiosurgery was performed. This series started in 1977. All the tumours received a single radiosurgical session (with a mean dose of 21.7 Gy, 5–10mm. collimator; one patient received two sessions and in another patient two different targets were irradiated in the same session). Prior to radiosurgery, six patients received conventional external fractionated radiotherapy, with two lateral fields of up to 10 × 10 cm. and a mean dose of 55.1 Gy. and another six patients with tumours less than 5 cm. in diameter, received stereotactic radiotherapy using four fields of up to 5 × 5 cm. and a mean dose of 53.1 Gy. I…
Meningiomas del agujero magno y primeros segmentos cervicales
Resumen Se presentan 6 pacientes con meningiomas situados en el agujero magno recogidos durante los dos ultimos anos. La clinica inicial que presentaban fue totalmente inespecifica simulando la mayoriade ellos un cuadro de espondilosis cervical. El diagnostico morfologico de la lesion se baso en la TC y RM de fosa posterior y primeros segmentos cervicales. Con estas pruebas se confirmo la presencia de una masa tumoral, de caracter intradural y de contornos bien definidos, con presentacion lateral en 4 casos y anterior en 2. En todos los casos se procedio de forma precoz a la reseccion total de la masa tumoral intradural por via posterior a traves de una craniectomia suboccipital y laminecto…
Stereotactic Radiotherapy plus Radiosurgical Boost in the Treatment of Large Cerebral Arteriovenous Malformations
Small sized AVMs respond well to stereotactic radiosurgery, while larger AVMs do poorly with stereotactic radiosurgery or stereotactic fractionated radiotherapy. A combination of both methods is proposed for the treatment of these larger lesions.
Radiosurgery of Epilepsy
Since 1982 a series of 11 epileptic patients have been treated with stereotactic radiosurgery. Patients were intracranially recorded with cortical and deep electrodes until the location of the epileptogenic focus was determined. A deep electrode was stereotactically placed at this point to confirm the accuracy of the location. All patients received radiosurgery with a gamma source and a dose of 10 to 20 Gy, except two of them in which a betatron was used. The results were: Total disappearance of the crises and withdrawal of medication: 4 cases (36%). More than 80% reduction of crises: 3 cases (27%). More than 50% reduction of crises: 2 cases (18%). Less than 50% reduction of crises: 2 cases…
Radiosurgery of Carotid-Cavernous Fistulae
25 cases of carotid-cavernous fistulae (CCF) who underwent radiosurgery with a conventional gamma source from 1977 to 1992 are reported. 22 were low-flow, spontaneous CCFs and 3 were high flow fistulae which had undergone a previous trApplng. The total dose delivered was 30 to 40 Gy. 91% to patients with low-flow CCF cured after radiosurgery in a mean time of 7.5 months, presenting improvent in a mean time of 2.3 months. Only one of the high-flow fistulae was cured. Follow-up period ranged between 14 years and 15 months (mean: 50 months). No recurrence was recorded in any case. While intravascular embolotherapy is the treatment of choice for high-flow fistulae, stereotactic radiosurgery may…