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Biomedical subjects

L Casentini

Publications and source records attributed to L Casentini.

18 recordsLinked to original sources
PubMed1991

Development of a second generation stereotactic apparatus for linear accelerator radiosurgery.

Linear accelerator radiosurgery technique is based on a multiple intersecting arc irradiations procedure. The coincidence of the axis of two rotation movements (of gantry and treatment couch) into the isocenter is critical for focusing irradiation. In October 1989, our linear accelerator was changed and the stereotactic apparatus had to be adapted to the new machine. After multiple mechanical tests of the new machine, the stereotactic head frame was fixed to the roller bearing allowing rotation of the couch. The new apparatus is described.

Humans↗
PubMed1990

Combined radiosurgery and external radiotherapy of intracranial germinomas.

Germinomas are successfully treated with radiation therapy; we have observed six cases that have been stereotactically irradiated by means of a linear accelerator (radiosurgery). In most cases a single dose of stereotactic irradiation effects the reduction of the tumor volume in a few days. External whole brain and, in two cases, spinal irradiation completed the treatment to avoid seeding of tumor cells. The technique and the advantages of this original therapeutical approach to intracranial germinomas are described and discussed.

Adolescent↗
PubMed1989

Low-grade astrocytomas: treatment with unconventionally fractionated external beam stereotactic radiation therapy.

Fourteen patients with nonoperable low-grade astrocytomas were treated with unconventionally fractionated stereotactic radiation therapy. The target volume was defined with computed tomography (CT) performed under stereotactic conditions. The treatment was carried out with a technique producing multiple noncoplanar arc irradiation, with the center of the target volume placed at the isocenter of the linear accelerator. A total dose of 16-50 Gy was administered in either one fraction or two fractions 8 days apart. The concentration of dose within the target volume allowed reduction of dose absorbed by adjacent critical structures of the intact brain. Patients were followed up for 11-48 months. Twelve of 14 patients had a partial or complete response to treatment, as demonstrated by CT. Stereotactic radiation therapy appears to be effective in the control of small radioresistant cerebral neoplasms, without damaging surrounding healthy tissues.

Adolescent↗
PubMed1988

Validity of stereotactic biopsy as a diagnostic tool.

254 patients affected by intracranial lesions underwent stereotactic biopsy in our department from 1978 to 1986. Target localization was achieved by CT. Multiple biopsy sampling was performed by cup microforceps or sliding cannula. Operative mortality was limited to 2 cases. Definitive tumour diagnosis including type and approximate grading was obtained in 211 (83%) patients. Diagnostic failures have been investigated from the neuroradiological point of view. Failure rate is low in solid tumours with CT homogeneous appearance and clear-cut borders, gradually increases in non homogeneous tumours, necrotic haemorrhagic or cystic, and is high in non classifiable lesions, generally hypodense at CT, with indefinite borders. In the authors opinion the variability of diagnostic retrieval in different types of lesions must be taken into account when proposing stereotactic biopsy.

Biopsy↗
PubMed1987

Linear accelerator radiosurgery of arteriovenous malformations.

Forty-five patients affected by cerebral arteriovenous malformations not suitable to open surgery have been treated by a radiosurgical technique employing a linear accelerator. One-year follow-up angiography is available for 10 cases. Therapeutic effect of focalized irradiation is presented.

Adolescent↗
PubMed1985

Osteogenic osteosarcoma of the calvaria following radiotherapy for cerebellar astrocytoma: report of a case in childhood.

Sarcoma as a second malignant neoplasm following radiotherapy is a rare occurrence in childhood. A case of osteogenic osteosarcoma of temporoparietal bone that developed 56 months after irradiation for a cerebellar astrocytoma in a 10-year-old child is reported and the pertinent literature is briefly reviewed. The possibility of an association (in the same patient) between these two rather uncommon lesions is extremely unlikely. Therefore, it is possible that radiotherapy played a role in the induction of the sarcoma. The indolent course of the latter is stressed.

Astrocytoma↗
PubMed1984

[Biopsy and stereotaxic radiotherapy of cerebral gliomas].

The Authors report their experience on a series of 125 patients that underwent stereotactic biopsy. The procedure has proved reliable and almost risk -free. The diagnosis obtained from the bioptic specimen by smear technique-cytological examination and by paraffin embedding-histological examination are compared. Neuropathologic data were also checked by the examination of the tumor bulk in cases that underwent surgical removal or autoptic verification. The preliminary results obtained in 8 patients with the new technique of external stereotactic irradiation by means of a linear accelerator are also shown.

Biopsy↗
PubMed1984

A new dynamometric technique to measure and locate endocranial structures. Preliminary report.

An apparatus for measuring and recording the resistance to penetration of endocranial tissue has been planned and built. The probe carrier, driven by a constant-speed electric motor, is fitted onto a stereotactic head frame which is used to guide the tool to the intended target. The displacement and resistance encountered when the tool penetrates intracranial structures are measured and recorded on an x-y recorder. Preliminary tests performed on calf brain specimens have documented that the apparatus can measure the different consistencies of normal cerebral tissue and suggest a new technique for morphological investigations based on the mechanical consistency of normal and pathological organic tissue. Moreover, the hypothesis of a plastic deformation in cerebral tissue has been confirmed, in that the same apparatus permits one to measure the displacement of tissues caused by the advancement of the surgical tool.

Biopsy↗
PubMed1981

Clinical and morphological investigations on ependymomas and their tissue cultures.

A morphological investigation was carried out on 56 ependymomas cultivated in vitro as short-term cultures in roller tubes. The tumours had been histologically classified as cellular and fibrillary ependymomas, subependymomas, myxopapillary and malignant ependymomas (Table 1). A very good growth was detected in 32 cases, most of them being cellular and malignant ependymomas (Table 2). The prevailing growth pattern was epithelial in type, i.e. proliferating cells forming a carpet. In some cases, in the first stages of growth elongated bipolar cells did appear, but they evolved later as flattened epithelial elements. In four cases, a mixed proliferation of piloid astrocytes and ependymal cells was seen; these tumours were regarded as mixed gliomas. In 46 cases an exact evaluation of the history was possible. Although no correlation could be found between histology and survival time (Table 4), the longest survival was observed in spinal tumours (Table 3). Tumours in children had a slightly worse prognosis in comparison with adults (Table 5). A radical removal of the tumour was generally followed by a longer survival time (Table 6), although the operative procedure employed did not seem to influence the development of recurrences (Table 7).

Adult↗
PubMed1981

Multiple meningiomas.

The authors discuss the criteria of differential diagnosis for a correct use of the term "multiple meningiomas". Reviewing a series of 934 meningiomas, of which 834 were intracranial and 100 were spinal, they found 14 cases of multiple meningiomas, i.e. an incidence of 1.5%. The study shows that multiple meningiomas are quite similar to solitary meningiomas in all their biological characteristics. Furthermore, the possible presence of more than one meningioma must always be kept in mind in the clinical and radiological evaluation of a patient. The aetiology of multiple separate meningiomas is discussed: the hypothesis which suggests their origin from multicentric neoplastic foci activated by a supposed "tumour-producing factor" appears to be the most reliable.

Adult↗
PubMed1980

Giant cell gliomas of the temporal lobe.

Giant cell tumours of the brain are commonly a) monstrocellular sarcomas, b) giant cell glioblastomas or gliosarcomas, or c) "giant cell gliomas", i.e. gliomas characterized by many atypical, giant-sized cells with monstrous nuclei. This last group is commonly found in the temporal region and should not be mistaken for a) and b), because, in spite of their "malignant" appearance, these tumours can present benign biological behaviour. Three such cases are described. In two cases the patients received postoperatively neither radio- nor chemotherapy: seven and three years respectively after operation no signs of recurrences were present. A third patient died within two years after operation. However, his tumour had histological signs of malignancy. The importance of exact histological diagnosis is stressed. This prevents misinterpretations in estimating the efficacy of postoperative therapy.

Adult↗
PubMed1979

Choroid plexus carcinoma. Case report.

Plexus-chorioideus carcinomata or malignant plexus papillomas are very rare; only few cases have been described in the literature. A further observation is added now. In a 13-year-old girl, signs of brain pressure occured two weeks before admission to a hospital. Scintigraphy and vertebral angiography showed a process in the atrium of the right lateral ventricle which was removed by temporo-parietal trephination. The tumour had the size of an apricot and a reddish colouration, it proceeded from the plexus. After-irradiation with 5 000 rad. Six years after the operation, signs of brain pressure appeared again. Neuroradiologically the process was located in the right cerebellar hemisphere. After trephination of the cerebellum, the largely vascularised tumour, which appeared to originate from the tela choroidea of the 4th ventricle, could be removed. The further course was without pathological findings. Histologically, the typical criteria were found: Invasion of surrounding brain structures, loss of the regular papillary structure, malignisation of the cells and originating from the plexus choroideus.

Adolescent↗
PubMedDate not supplied

The posterior approach to cervical rizopathy.

The posterior approach to cervical rizopathy is a widely acquired technique; however only recently it encountered more favorable consideration. After a brief review of the literature, the Authors present some details of surgical approach, discuss its value and its limits with a comment on their own series.

Adult↗
PubMedDate not supplied

Radical excision of a craniobasal tumor involving the middle cranial fossa. Technical note.

Craniobasal tumors affecting the middle cranial fossa are rarely treated radically; the main problem to solve is the presence of important nervous and vascular structures in this region. The Authors report a case of complete removal of a malignant tumor involving the temporal bone and the middle cranial fossa. Surgery was performed by the cooperation of the neurosurgical and the ENT teams.

Adult↗
PubMedDate not supplied

Stereotactic biopsy of low-grade giant-cell astrocytoma.

Stereotactic biopsy was used to sample a hypodense lesion of the left temporo-occipital lobes in a 32-year-old female with a history of grand mal seizures. Although the intraoperative cytologic examination showed a picture suggestive of malignancy, including giant cells and atypical mitotic figures, the clinical and radiologic history militated against a malignant nature for the lesion, which was thus classified as a low-grade giant-cell astrocytoma. This case emphasizes both the utility of intraoperative cytologic examination of stereotactic biopsy specimens and the need to consider the cytologic and histologic evidence in light of the clinical and radiologic findings.

Adult↗
PubMedDate not supplied

Stereotactic radiosurgery of intracranial tumors in childhood.

The Authors have developed an original stereotactic technique by which the radiation dose erogated by a 4 MV linear accelerator is focused into the target volume with a steep dose gradient at its borders. The technique has been employed in a series of 30 patients affected by deep seated brain tumors and AVMs. The paper deals with the preliminary results obtained in a series of 10 patients in pediatric age.

Adolescent↗