The role of photodynamic therapy in posterior fossa brain tumors

1993 ◽  
Vol 79 (4) ◽  
pp. 562-568 ◽  
Author(s):  
Harry T. Whelan ◽  
Meic H. Schmidt ◽  
Annette D. Segura ◽  
Timothy L. McAuliffe ◽  
Dawn M. Bajic ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Brain Tumors ◽  
Brain Stem ◽  
Posterior Fossa ◽  
Laser Light ◽  
Neurological Deficits ◽  
High Dose ◽  
Normal Brain ◽  
Content Type ◽  
Photofrin Ii

✓ Photodynamic therapy was studied in dogs with and without posterior fossa glioblastomas. This mode of therapy consisted of intravenous administration of Photofrin-II at doses ranging from 0.75 to 4 mg/kg 24 hours prior to laser light irradiation in the posterior fossa. Tissue levels of Photofrin-II were four times greater in the tumor than in the surrounding normal brain. Irradiation was performed using 1 hour of 500 mW laser light at a wavelength of 630 nm delivered through a fiberoptic catheter directly into the tumor bed via a burr hole. All animals receiving a high dose (4 or 2 mg/kg) of Photofrin-II developed serious brain-stem neurotoxicity resulting in death or significant residual neurological deficits. A lower dose (0.75 mg/kg) of Photofrin-II produced tumor kill without significant permanent brain-stem toxicity in either the control animals or the animals with cerebellar brain tumors receiving photodynamic therapy.

Successful evacuation of a pontine hematoma secondary to rupture of a pathologically diagnosed “cryptic” vascular malformation

1973 ◽  
Vol 39 (1) ◽  
pp. 104-108 ◽  
Author(s):  
Ben B. Scott ◽  
Joachim F. Seeger ◽  
Richard C. Schneider
Keyword(s):  
Arteriovenous Malformation ◽  
Brain Stem ◽  
Posterior Fossa ◽  
Vascular Malformation ◽  
Nerve Palsy ◽  
Neurological Deficits ◽  
Content Type ◽  
Brain Stem Lesion ◽  
Seventh Nerve ◽  
Fine Print

✓ A posterior fossa exploration was performed on a child thought initially to have an inoperable brain stem lesion. A pontine hematoma was discovered and evacuated. The pathological specimen was designated as a “cryptic” arteriovenous malformation. All preoperative neurological deficits disappeared except for a minimal left seventh nerve palsy.

Thiamine-deficient lactic acidosis with brain tumor treatment

1998 ◽  
Vol 89 (6) ◽  
pp. 1025-1028 ◽  
Author(s):  
Hiroshi Kuba ◽  
Takanori Inamura ◽  
Kiyonobu Ikezaki ◽  
Masatou Kawashima ◽  
Masashi Fukui
Keyword(s):  
Brain Tumor ◽  
Lactic Acidosis ◽  
Brain Tumors ◽  
Neurological Deficits ◽  
High Dose ◽  
Content Type ◽  
Malignant Brain Tumors ◽  
Level Of Consciousness ◽  
Lactic Acidemia ◽  
Fine Print

✓ Lactic acidosis due to thiamine deficiency is known to complicate chemotherapy and radiotherapy treatment of malignant extracranial tumors, but to the authors' knowledge, this complication has not been reported in patients treated for malignant brain tumors. They report three such cases, demonstrating that this complication can occur during treatment of brain tumors. In all patients, consciousness levels deteriorated within 1 to 2 days. Serum lactic acid levels increased to concentrations between 62 and 96.7 mg/dl, resulting in severe metabolic acidosis. A low blood thiamine level (9 ng/ml) was demonstrated at the onset in one case, and high-dose thiamine infusions dramatically improved lactic acidemia as well as impairment of consciousness in two cases. In the other case, hydrocephalus was suspected initially, resulting in a delay in thiamine supplementation. Clinical differentiation of this form of lactic acidosis from hydrocephalus or tumor progression can be very difficult in a patient undergoing treatment for a malignant brain tumor. Demand for thiamine is thought to be increased in patients with malignant brain tumors, and supplemental thiamine during treatment is necessary to prevent lactic acidosis. When this complication occurs, immediate treatment with sufficient thiamine is essential, together with normalization of pH by using sodium bicarbonate. With timely intervention, the level of consciousness can recover to the preacidotic state with no new neurological deficits.

Intraoperative monitoring of brain-stem auditory evoked potentials

1982 ◽  
Vol 57 (3) ◽  
pp. 341-348 ◽  
Author(s):  
Peter A. Raudzens ◽  
Andrew G. Shetter
Keyword(s):  
Evoked Potentials ◽  
Brain Stem ◽  
Auditory Evoked Potentials ◽  
Neurological Deficits ◽  
Additional Patient ◽  
Content Type ◽  
Intracranial Surgery ◽  
Surgical Measures ◽  
Evoked Potential Monitoring ◽  
Operating Surgeon

✓ Intraoperative brain-stem auditory evoked potentials (BAEP's) were monitored in 46 patients undergoing intracranial surgery for a variety of pathological conditions to determine whether this technique was capable of providing useful information to the operating surgeon. Intraoperative BAEP's were unchanged throughout surgery in 34 patients (74%), and these individuals had no postoperative hearing deficits. Four patients (9%) developed an abrupt ipsilateral loss of all waveform components beyond Wave I and had postoperative evidence of a pronounced hearing loss in the affected ear. An additional patient demonstrated BAEP loss contralateral to the side of surgery, and this was associated with subsequent signs of severe brain-stem dysfunction. Seven patients (15%) developed intraoperative delays of BAEP waveform latency values, but maintained recognizable waveforms beyond Wave I. Postoperatively, their hearing was either normal or mildly impaired, and there were no indications of other brain-stem abnormalities. This group represents the individuals who may have been benefited by evoked potential monitoring, since corrective surgical measures were taken when latency delays were observed. Intraoperative BAEP's can be reliably and routinely recorded in an operating room environment. They provide a good predictor of postoperative auditory status, and may have prevented permanent neurological deficits in a small segment of patients by alerting the surgeon to potentially reversible abnormalities.

Arteriovenous malformations in the posterior fossa

1977 ◽  
Vol 47 (1) ◽  
pp. 50-56 ◽  
Author(s):  
Hiroshi Matsumura ◽  
Yasumasa Makita ◽  
Kuniyuki Someda ◽  
Akinori Kondo
Keyword(s):  
Arteriovenous Malformation ◽  
Brain Stem ◽  
Posterior Fossa ◽  
Arteriovenous Malformations ◽  
Cerebellopontine Angle ◽  
Anterior Part ◽  
Content Type ◽  
The Brain ◽  
Fine Print

✓ We have operated on 12 of 14 cases of arteriovenous malformation (AVM) in the posterior fossa since 1968, with one death. The lesions were in the cerebellum in 10 cases (three anteromedial, one central, three lateral, and three posteromedial), and in the cerebellopontine angle in two; in two cases the lesions were directly related to the brain stem. The AVM's in the anterior part of the cerebellum were operated on through a transtentorial occipital approach.

The deposition of Hg203-chlormerodrin in experimental brain tumors

1971 ◽  
Vol 35 (3) ◽  
pp. 303-308 ◽  
Author(s):  
Tatsuya Kobayashi ◽  
Louis Bakay ◽  
Joseph C. Lee
Keyword(s):  
Brain Tumors ◽  
Tumor Cells ◽  
Normal Brain ◽  
Intracranial Tumors ◽  
Electron Microscopic ◽  
Electron Microscopic Autoradiography ◽  
Content Type ◽  
Meningeal Tumors ◽  
Vacuolar System ◽  
Fine Print

✓ The deposition of Hg203-chlormerodrin was studied in intracranial tumors in mice induced by implantation of 20-methyl cholanthrene by tissue assay, as well as light microscopic and electron microscopic autoradiography. The investigations were carried out in astrocytomas, glioblastomas, and meningeal tumors. The chlormerodrin content of the tumors exceeded that of normal brain with a significant tumor/brain ratio ranging from 5.8 to 22.5. It was found that the chlormerodrin molecule becomes rapidly incorporated in the tumor cells, with a preference for that portion of the cytoplasm associated with the vacuolar system.

Quantification and pharmacokinetics of blood-brain barrier disruption in humans

1996 ◽  
Vol 85 (6) ◽  
pp. 1056-1065 ◽  
Author(s):  
Bernhard Zünkeler ◽  
Richard E. Carson ◽  
Jeff Olson ◽  
Ronald G. Blasberg ◽  
Hetty Devroom ◽  
...  
Keyword(s):  
Brain Tumors ◽  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Normal Brain ◽  
Content Type ◽  
Barrier Disruption ◽  
Blood Brain Barrier Disruption ◽  
Blood Brain ◽  
Brain Barrier Disruption ◽  
Fine Print

✓ Hyperosmolar blood-brain barrier disruption (HBBBD), produced by infusion of mannitol into the cerebral arteries, has been used in the treatment of brain tumors to increase drug delivery to tumor and adjacent brain. However, the efficacy of HBBBD in brain tumor therapy has been controversial. The goal of this study was to measure changes in vascular permeability after HBBBD in patients with malignant brain tumors. The permeability (K1) of tumor and normal brain blood vessels was measured using rubidium-82 and positron emission tomography before and repeatedly at 8- to 15-minute intervals after HBBBD. Eighteen studies were performed in 13 patients, eight with glioblastoma multiforme and five with anaplastic astrocytoma. The HBBBD increased K1 in all patients. Baseline K1 values were 2.1 ± 1.4 and 34.1 ± 22.1 µl/minute/ml (± standard deviation) for brain and tumor, respectively. The peak absolute increases in K1 following HBBBD were 20.8 ± 11.7 and 19.7 ± 10.7 µl/minute/ml for brain and tumor, corresponding to percentage increases of approximately 1000% in brain and approximately 60% in tumor. The halftimes for return of K1 to near baseline for brain and tumor were 8.1 ± 3.8 and 4.2 ± 1.2 minutes, respectively. Simulations of the effects of HBBBD made using a very simple model with intraarterial methotrexate, which is exemplary of drugs with low permeability, indicate that 1) total exposure of the brain and tumor to methotrexate, as measured by the methotrexate concentration-time integral (or area under the curve), would increase with decreasing infusion duration and would be enhanced by 130% to 200% and by 7% to 16%, respectively, compared to intraarterial infusion of methotrexate alone; and 2) exposure time at concentrations above 1 µM, the minimal concentration required for the effects of methotrexate, would not be enhanced in tumor and would be enhanced by only 10% in brain. Hyperosmolar blood-brain barrier disruption transiently increases delivery of water-soluble compounds to normal brain and brain tumors. Most of the enhancement of exposure results from trapping the drug within the blood-brain barrier, an effect of the very transient alteration of the blood-brain barrier by HBBBD. Delivery is most effective when a drug is administered within 5 to 10 minutes after disruption. However, the increased exposure and exposure time that occur with methotrexate, the permeability of which is among the lowest of the agents currently used clinically, are limited and the disproportionate increase in brain exposure, compared to tumor exposure, may alter the therapeutic index of many drugs.

Localized 31P magnetic resonance spectroscopy of large pediatric brain tumors

1990 ◽  
Vol 72 (1) ◽  
pp. 65-70 ◽  
Author(s):  
Leslie N. Sutton ◽  
Robert E. Lenkinski ◽  
Bruce H. Cohen ◽  
Roger J. Packer ◽  
Robert A. Zimmerman
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Brain Tumors ◽  
Malignant Tumors ◽  
Benign Tumors ◽  
Resonance Spectroscopy ◽  
Normal Brain ◽  
Content Type ◽  
Metabolic Fingerprint

✓ Fourteen children aged 1 week to 16 years, with a variety of large or superficial brain tumors, underwent localized in vivo 31P magnetic resonance spectroscopy of their tumor. Quantitative spectral analysis was performed by measuring the area under individual peaks using a computer algorithm. In eight patients with histologically benign tumors the spectra were considered to be qualitatively indistinguishable from normal brain. The phosphocreatine/inorganic phosphate ratio (PCr/Pi) averaged 2.0. Five patients had histologically malignant tumors; qualitatively, four of these were considered to have abnormal spectra, showing a decrease in the PCr peak. The PCr/Pi ratio for this group averaged 0.85, which was significantly lower than that seen in the benign tumor group (p < 0.05). No difference between the two groups was seen in adenosine triphosphate or phosphomonoesters. It is concluded that a specific metabolic “fingerprint” for childhood brain tumors may not exist, but that some malignant tumors show a pattern suggestive of ischemia.

The effect of interleukin-2 on the blood-brain barrier in the 9L gliosarcoma rat model

1989 ◽  
Vol 70 (1) ◽  
pp. 92-96 ◽  
Author(s):  
Joseph T. Alexander ◽  
Stephen C. Saris ◽  
Edward H. Oldfield
Keyword(s):  
Blood Brain Barrier ◽  
Interleukin 2 ◽  
Brain Barrier ◽  
High Dose ◽  
Normal Brain ◽  
Content Type ◽  
Tumor Bearing ◽  
Blood Brain ◽  
Significant Difference ◽  
Fine Print

✓ Carbon-14-labeled aminoisobutyric acid was used to determine local blood-to-tissue transfer constants in 22 Fischer rats with intracerebral 9L gliosarcomas that received either high-dose parenteral interleukin-2 (IL-2) or a control injection. In tumor and peritumoral tissue, the transfer constants in the IL-2-treated animals (89.6 ± 14.6 and 35.8 ± 6.0, respectively, mean ± standard error of the mean) were larger (p < 0.05) than in control animals (61.4 ± 6.4 and 14.6 ± 2.2, respectively). In contrast, in normal frontal and occipital tissue contralateral to the tumor-bearing hemisphere, there was no significant difference between the transfer constants in IL-2-treated and control animals. Furthermore, treatment of animals with IL-2 excipient caused no change in permeability as compared to animals treated with Hanks' balanced salt solution. Parenteral injection of IL-2 increases blood-brain barrier disruption in tumor-bearing rat brain but does not increase the vascular permeability of normal brain. Methods to prevent this increased tumor vessel permeability are required before parenteral IL-2 can be used safely for the treatment of primary or metastatic brain tumors.

scholarly journals Tumeurs Cerebrales de l'enfant en milieu Canadien-Francais

1979 ◽  
Vol 6 (3) ◽  
pp. 329-335 ◽  
Author(s):  
F. Renevey ◽  
Y. Amyot ◽  
G. Geoffroy ◽  
M. Vanasse
Keyword(s):  
Brain Tumors ◽  
Brain Stem ◽  
Posterior Fossa ◽  
Clinical Investigation ◽  
Clinical Manifestations ◽  
Tumeurs Cérébrales ◽  
Brain Stem Lesions ◽  
Stem Lesions ◽  
Invasive Techniques ◽  
Intra Cranial Pressure

SUMMARY:Between 1964 and 1976, we have seen 197 cases of cerebral tumors in children. We have studied the frequency of each histological group of tumors, their localization, the results of the clinical investigation, their clinical manifestations and the prognosis for each group.This study has confirmed that in children brain tumors are more frequently localized in the posterior fossa (56.4%). As in other series, tumors derived from the glia represent nearly 80% of the total. Clinically, increased intra-cranial pressure is the most frequent manifestation of posterior fossa lesion (75% of cases) while cerebellar involvement was seen in 60% of these childdren. Brain stem lesions and supratentorial tumors are more insidious in their presentation and their clinical manifestations more diversified.The EEG appeared useful in the investigation of brain tumors and showed irregularities in 78% of our patients. However, a more specific diagnosis required more invasive techniques such as angiography, pneumoencephalography or ventriculography.As in previous series, the mortality rate remained high in the children we have followed, particularly for some groups of tumors (glioblastoma, medulloblastoma, brain stem lesions). It is to be hoped that with the introduction of the CT Scan, the improvement of neurosurgical techniques and the use of immuno and chemotherapy, the prognosis may be improved.

Cerebrovascular permeability and delivery of gentamicin to normal brain and experimental brain abscess in rats

1984 ◽  
Vol 61 (3) ◽  
pp. 430-439 ◽  
Author(s):  
Edward A. Neuwelt ◽  
David E. Baker ◽  
Michael A. Pagel ◽  
Nathan K. Blank
Keyword(s):  
Brain Abscess ◽  
Blood Brain Barrier ◽  
Medical Management ◽  
Brain Barrier ◽  
High Dose ◽  
Normal Brain ◽  
Content Type ◽  
Stage Of Development ◽  
Blood Brain ◽  
Brain Abscesses

✓ Antibiotics vary widely in their ability to penetrate the blood-brain barrier. In studies of 70 rats, the permeability of the normal blood-brain barrier to gentamicin was shown to be poor. In experimental brain abscesses, during the cerebritic stage of development, the penetration of intravenous antibiotics was increased compared to normal brain but was very inconsistent. Antibiotic delivery to brain abscess was not significantly altered with the administration of high-dose steroids, but the macrophage and glial response was markedly decreased with high-dose steroid therapy. Reversible osmotic blood-brain barrier modification with mannitol increased the delivery of gentamicin both to brain abscess and to the surrounding brain. It also resulted in more consistent tissue drug levels. The clinical implications of these studies suggest that, because of the inconsistent delivery of gentamicin to brain abscess, the therapeutic efficacy of medical management alone may be quite variable. This mode of therapy could possibly increase the efficacy of medical management of brain abscesses, especially in patients with multiple or surgically inaccessible brain abscesses.

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