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Biomedical subjects

B Guidetti

Publications and source records attributed to B Guidetti.

At least 19 recordsLinked to original sources
PubMed1990

Choroid plexus papillomas in infancy and childhood.

The present study deals with 15 cases of choroid plexus papilloma, out of approximately 500 cases of brain tumors observed in children up to 16 years old. Several features are considered, including clinical symptoms and signs--mostly related to increased intracranial pressure--radiological diagnosis, pathology and surgical treatment, and results. Surgery may be radical in most cases, with the exception of histologically malignant papillomas. The management results are usually satisfactory. An adequate choice of surgical approach is mandatory and surgical technique should be meticulous, also in order to avoid the risk of intraoperative tumoral seeding.

Adolescent↗
PubMed1989

Treatment of trigeminal neuralgia by thermocoagulation, glycerolization, and percutaneous compression of the gasserian ganglion and/or retrogasserian rootlets: long-term results and therapeutic protocol.

From 1976 to 1986, 681 patients with drug-refractory trigeminal neuralgia (TN)--typical in 641, symptomatic of multiple sclerosis in 23 and of tumor in 10, atypical in 5, and postherpetic in 2--were treated with various percutaneous procedures. Controlled differential thermocoagulation of the gasserian ganglion and/or retrogasserian rootlets was performed in 533 patients; glycerolization of the trigeminal cistern in 32; and compression of the gasserian ganglion by balloon catheter in 159. Results and complications of each procedure are assessed at a mean follow-up of 6.5 years for thermocoagulation, 5 years for glycerolization, and 3.5 years for compression. The following therapeutic protocol is proposed: 1) in TN patients at first operation: a) gasserian compression (or glycerolization, if experience warrants it) is indicated in all cases of typical TN, unless the 3rd division alone is affected; b) in the latter case and in symptomatic TN, we suggest thermocoagulation; 2) in recurrences: a) after glycerolization or gasserian compression, gasserian compression (or glycerolization) is indicated; b) after thermocoagulation or open surgery, thermocoagulation is suggested.

Catheterization↗
PubMed1989

Multiple intracranial meningiomas.

The authors report 14 cases of multiple intracranial meningiomas representing 1.1% of all meningiomas operated on at their hospital in the past 35 years. Differentiation of multiple meningiomas, especially from meningiomatosis, must be strict. Since the introduction of computerized tomography scanning, the frequency of these cases has risen from 0.58% to 4.5% in the authors' meningioma series. Despite the multiplicity of sites, multiple meningiomas do not differ in prognosis from benign solitary meningiomas.

Adult↗
PubMed1988

The response of peripheral blood mononuclear cells of glioma-bearing patients to stimulation with microbial antigen and IL-2: proliferation and IFN-gamma production.

Peripheral blood mononuclear cells (PBMC) of malignant glioma-bearing patients were stimulated in vitro with a glucomannan-protein antigen of Candida albicans (GMP) or Interleukin-2 (IL-2), then assayed for proliferation and production of Interferon gamma. PBMC of healthy, age and sex matched subjects were the controls. PBMC from glioma-bearing patients did not differ, as a whole, from PBMC of healthy donors in IL-2 or GMP-induced proliferation. However, they showed a definitely lesser ability to produce IFN. The results are discussed in the framework of the impairment of immune responses known to affect glioma-bearing patients.

Antigens, Fungal↗
PubMed1988

Tentorial meningiomas: surgical experience with 61 cases and long-term results.

The authors report their experience and long-term results in the surgical treatment of 61 tentorial meningiomas. These cases were operated on between 1951 and 1985 and represented 4.8% of all intracranial meningiomas operated on in that period. The mean duration of clinical history was 29 months, except for cases of meningioma of the posteromedial border, for which it was 5 years. Plain x-ray films and cerebral angiograms were obtained in all cases. Computerized tomography, performed in the last 20 cases (32.7%), supplied much better lesion topography and early diagnosis. The tumor site was posterolateral in 26 cases (42.6%), anterolateral in 14 (22.9%), posteromedial in eight (13.1%), at the free border in seven (11.4%), and in the tentorium itself in six (9.8%). Lateral and medial tumors with solely or mainly supratentorial development were approached from above. The approach from below was reserved for meningiomas with subtentorial involvement only. In meningiomas with both supra- and subtentorial growth, a supratentorial bone flap was combined with a suboccipital craniectomy using a retromastoid incision. The mortality rate was 9.8%. Of the remaining 42 patients, who were followed for at least 5 years, long-term results were good in 26 cases (61.9%), fair in 11 (26.2%), and poor in five (11.9%). Postoperative complications arose in 34% of the patients, but cleared in 27%.

Adult↗
PubMed1987

Results of surgical management of 319 pituitary adenomas.

Of the 510 patients with pituitary adenoma treated surgically at our hospital in the period 1956-1984 319 were treated by the microsurgical technique, in the period 1973-1984, 235 by transsphenoidal approach and 84 by subfrontal-pterional approach. The transsphenoidal route was used almost exclusively in microadenomas, in intrasellar adenomas, in suprasellar adenomas with midline development, in adenomas invading the sphenoidal sinus and in haemorrhagic adenomas with considerable suprasellar development. In some giant adenomas the transsphenoidal route was used in a first stage operation for debulking the tumour, later removed by transcranial route. The latter route was preferred in large adenomas and especially in adenomas with laterosellar development. In some patients with PRL secreting adenomas post-operative treatment with bromocriptine proved useful when the hormone levels failed to normalize. Post-operative radiotherapy was of value in invasive adenomas and in cases in which tumour removal was not radical.

Adenoma↗
PubMed1987

Immunocomplexes in rat and rabbit spinal cord after injury.

The possibility that, following a major lesion of the central nervous system, a humoral immune response could be evoked with formation of immune complexes "in situ" was investigated. For this purpose, an immunohistochemical study on rabbit and rat spinal cord at different times after surgical transection was carried out. The peroxidase-antiperoxidase method showed IgG decoration of the myelin sheaths starting a short time after surgery. The sera of intact and injured animals were then tested both by immunohistochemical methods on intact spinal cord sections and by immunoelectrophoresis on a protein extract of homologous spinal cord. The results showed in the rabbit the absence of antibodies to neural antigens before surgical injury and its appearance within a few days after surgery. On the other hand, in the rat, even before the injury, we found antibodies to neural tissue which decreased in the first few hours after injury, and returned to control values during successive days. The same experiments were conducted after a peripheral nerve lesion (sciatic nerve crush), but no immune response could be detected. The possible role of this immune response in the failure of axonal regeneration in mammalian spinal cord is briefly discussed.

Animals↗
PubMed1987

Relationship between leukocytosis and ischemic complications following aneurysmal subarachnoid hemorrhage.

The prognostic significance of admission leukocytosis with respect to ischemic complications of subarachnoid hemorrhage was retrospectively investigated in a series of patients with recently ruptured intracranial aneurysms. The present study concerned 47 consecutive cases admitted within 72 hours following the last hemorrhage, in the years 1982-1984. There was no difference in the admission WBC counts between patients who subsequently deteriorated due to ischemic complications and those who did not. However, the cell count rose significantly at the time of the clinical manifestations of ischemia, possibly as a result of structural damage of brain tissue and/or increased sympathetic and adrenocortical activity. The possible contribution of leukocytes to the pathogenesis of ischemic damage following subarachnoid hemorrhage--perhaps through the release of leukotrienes--will require further investigation.

Female↗
PubMed1987

Low-dose tranexamic acid combined with aprotinin in the pre-operative management of ruptured intracranial aneurysms.

Among our patients with ruptured intracranial aneurysms 149 were managed pre-operatively with a combination of tranexamic acid (AMCA), 3 gm daily, and aprotinin at an average of 400,000 KIU (Kallikrein inactivating units) daily. Antifibrinolytics were started within three days of the last haemorrhage, and continued for at least six days. The first 91 cases, managed in the years 1971 to 1980, have been evaluated retrospectively. The remaining 58 patients were managed in the period 1981-1985 and carefully watched for possible complications of treatment. No significant differences were noted in the results of patients managed either before or after 1981. The rate of recurrent SAH (10%) was lower than the natural history of aneurysmal SAH. Satisfactory inhibition of fibrinolysis was documented in the CSF collected at the time of operation in 15 patients. This, as well as our previous suggestions that the combination of low-dose AMCA and aprotinin might carry a lesser risk of causing ischaemic complications and hydrocephalus than the conventional antifibrinolytic treatment, might stimulate future studies on fibrinolysis in SAH.

Adult↗
PubMed1987

Pharmacokinetics of recombinant interferon-alpha 2 following intralesional administration in malignant glioma patients.

Pharmacokinetics of recombinant interferon-alpha 2 (rIFN-alpha 2) following intralesional administration into patients with malignant gliomas was investigated. A dose of 5 X 10(6) IU of rIFN-alpha 2 was injected locally postoperatively for 2 weeks each day, and the same dose was then given once a week for 10 additional weeks. During the daily and weekly administration, the IFN was consistently present in the fluid of the postsurgical cavity. Not until 5 weeks after the end of the IFN administration was the IFN undetectable. The decay of IFN injected was minimal.

Adult↗
PubMed1987

Crossed cerebellar diaschisis in patients with cerebral ischemia assessed by SPECT and 123I-HIPDM.

Crossed cerebellar diaschisis (CCD) was investigated in a series of 59 patients (34 completed strokes and 25 reversible ischemic attacks, RIAs) using single photon emission computerized tomography (SPECT) with 123I-HIPDM as a cerebral blood flow (CBF) indicator. CCD was present in 17 (50%) of the patients with completed stroke and in 6 (24%) of the patients with RIAs. CCD was significantly correlated to the clinical severity (p less than 0.001) and to the extension of the supratentorial lesion (p less than 0.05). However, CCD was also recorded in 3 out of 16 patients with normal neurological examination and CT scan, suggesting that a 'functional' hemispheric disturbance may be sufficient to produce a remote effect on the contralateral cerebellar hemisphere. Time elapsed between the clinical onset and SPECT study was not critical, since CCD was recorded in the acute as well as in chronic studies. Follow-up SPECT studies showed that CCD disappeared in 5 out of 18 patients after a successful extra-intracranial bypass, while a spontaneous recovery was observed in only one of 16 nonsurgical patients.

Adult↗
PubMed1987

Neurophysiologic assessment of trigeminal function after surgery for trigeminal neuralgia.

To assess the function of the three trigeminal divisions, we studied corneal reflex, early and late blink reflexes, early and late masseter silent periods, and jaw jerk in normal subjects and in 35 patients submitted to surgery for trigeminal neuralgia. The corneal reflex was most sensitive to thermocoagulation and the jaw jerk to microcompression; the other reflexes showed an intermediate behavior, depending on afferent fiber size. Trigeminal function was less impaired after microcompression and recovered earlier than after thermocoagulation.

Adult↗
PubMed1987

Neurosurgical use of human dura mater sterilized by gamma rays and stored in alcohol: long-term results.

Surgical experience with grafts of human dura mater sterilized by gamma rays and preserved in alcohol is reported in 804 cases. The method of graft preparation is a simple, cheap, and practical technique for making available a plentiful quantity of large and small pieces of dura to use for plastic reconstruction in everyday neurosurgical practice. Annual inspection for sterility and immunogenicity over an 18-year period indicates that this system of preservation is valid for an unlimited period of time.

Dura Mater↗
PubMed1986

[Subarachnoid hemorrhage caused by rupture of intracranial saccular aneurysm. Epidemiology, natural history, treatment].

The basic goal of surgical treatment of cerebral aneurysms is to prevent further bleeding and, if the malformation is large and compressed neighboring nervous structures, to free them from compression by the sac. Modern neurosurgical procedures can effectively achieve this aim. Proper application of surgery requires on accurate knowledge of the natural history of this disease that surgery is designed to treat. Only trough and understanding of both rebleeding rates and the natural history that the neurosurgeon can judge the proper timing of surgical intervention and assess the overall efficacy of his or her medical and surgical treatment. The therapeutic philosophy at our institution for years has been that the patients meeting the criteria of Botterel grade I and II are offered definitive intracranial surgery early in then posthemorrhagic period (first hours preferably or during the first 48-72 hours). More seriously ill patients are treated medically until their clinical condition seems stable and then subjected to surgical therapy. The only exception regard the patients in poor condition (grade III, IV and V) who reach the hospital quickly after hemorrhage (first hours). The patients undergo surgery at once. This timing, together with CT scanning, more aggressive medical and surgical treatment, and the operating microscope have lowered operative mortality and improved the quality of life.

Adolescent↗
PubMed1986

Prostaglandin E2 as an immunomodulating factor released in vitro by human glioma cells.

Cultured human glioma cells were found to produce soluble factors that can modulate the in vitro proliferative response of purified T lymphocytes stimulated by phytohemagglutinin (PHA). Neoplastic tissue was removed during surgery for brain glial tumors and cultured in vitro. The glial nature of the neoplastic cells was verified by means of anti-glial fibrillary acidic protein immunohistochemical staining. Serum-free supernatants from these cultures proved capable of suppressing in vitro proliferation of PHA-stimulated T lymphocytes. Suppression was reduced when indomethacin or aspirin was added to the culture medium. Thin-layer chromatography revealed the presence of prostaglandins and other arachidonic acid derivatives in the supernatants. The radioimmunoassay used to quantify the prostaglandin E2 (PGE2) in the supernatants showed detectable amounts of PGE2, which disappeared after the cultures had been treated with anti-inflammatory drugs. These data support the hypothesis that tumoral glial cells can play a role in the host immune response in the central nervous system, namely by producing soluble factors.

Antibody Formation↗