Jenö Julow

Long-term results and late complications after intracavitary yttrium-90 colloid irradiation of recurrent cystic craniopharyngiomas.

OBJECTIVE Data were analyzed to assess the value of stereotactically applied intracystic colloidal yttrium-90 (YTx) for the treatment of recurrent cystic craniopharyngiomas during a 30-year period. METHODS This article compares data from 73 YTx procedures in 60 patients between 1975 and 2006. The cumulative beta dose aimed at the inner surface of the cyst wall was 300 Gy. RESULTS After YTx, the initial cyst volumes decreased an average of 79%. In 47, the reduction was more than 80%; in 27 of them, the cyst disappeared completely within 1 year. The mean survival after YTx was 9.4 years (range, 0.7–30 yr). Actuarial survival rates at 5, 10, 15, 20, 25, and 30 years were 81, 61, 45, 18, 2, and 0%, respectively. Late complications of YTx were related to the anatomic localization of the cyst, either presellar and retrosellar, e.g., a presellar (prechiasmatic/suprasellar) localization caused neuro-ophthalmological complications in 5.8% and internal carotid artery injury in 1.6%. The treatment of retrosellar (retrochiasmatic, suprasellar) tumors occasionally induced hypothalamic and/or pontomesencephalothalamic damage obviously by untoward radiation to the so-called perforating arteries. This occurred in 3.2% of these latter patients. CONCLUSION Despite sporadic complications, intracavitary YTx irradiation is a valuable treatment alternative for craniopharyngioma cysts, sometimes as part of a multimodality management in these tumors, especially in precarious surgical cases.

The application of image fusion in stereotactic brachytherapy of brain tumours.

Summary Background. The visualization of any morphological volume (i.e. CT, MRI) together with an additional second morphological volume (i.e. CT, MRI) or functional data set, which may come from SPECT or PET, is a new method for treatment planning, verification and follow-up of interstitial irradiation. Method. The authors present their experience on interstitial irradiation of brain tumours with stereotactically implanted I-125 seeds supported by image fusion. The image fusion was performed by the BrainLab-Target 1.13 software on Alfa 430 (Digital) workstation before, during, and after interstitial irradiation of brain tumours with Iodine125 seeds. Results and Interpretation. On the basis of 20 brachytherapeutic image fusion of stereotactic CT (slices with fiducials) with additional stereotactic CT, MRI, PET and SPECT images provides more accurate and precise target volume, more exact localization of catheters and isotope seeds (verification fusion), differentiation between the localization and amount of the necrotic and proliferating parts of the tumours and shows the volume changes in consequence of interstitial irradiation. The image fusion should help to improve the accuracy and minimize the perifocal morbidity of interstitial irradiation.

Pathological changes in cystic craniopharyngiomas following intracavital90yttrium treatment

SummaryRadiosurgery, using90Y injected directly into the cavity of cystic craniopharyngiomas produces remarkable reduction of tumour size and diminishes cyst fluid production. The authors have studied the histology of biopsy and autopsy material obtained from seven patients presented with cystic craniopharyngiomas. Histological examination was carried out before and after90Y silicate implantation. As an effect of90Y irradiation, histology of samples taken from the cyst wall revealed that the lining epithelial cell layer became destroyed and the cyst wall shrunk. Large amount of collagen fibres with focal hyaline degeneration was present. Proliferation of intimal cells and subendothelial connective tissue narrowing small vessel lumina also occurred. Considering that fibrotic tissue is more susceptible to shrink, the fibrosis induced by irradiation together with destruction of the squamous epithelium and vascular changes, might explain the reduction of the cyst volume and diminished fluid secretion after90Y treatment.

Secretory component of cystic craniopharyngiomas: a mucino-histochemical and electron-microscopic study.

Ten cases with cystic craniopharyngioma were investigated. Histologically, eight of them belonged to the adamantinomatous group and two were squamous epithelial type. Histochemical investigation revealed mucin secretion in microcysts, and electron microscopy demonstrated zymogen granules in the epithelial cells. When the protein content of the cyst fluid was analyzed by polyacrylamide-gel electrophoresis, the electrophoretic pattern and immunological properties were found to be similar to the normal human serum control. The results of the morphological study suggest that cystic craniopharyngiomas have a secretory component in addition to the classical histological structures.

Iodine-125 Brachytherapy of Brain Stem Tumors

Purpose:To report on iodine-125 (125I) interstitial irradiation in the treatment of brain stem tumors.Patients and Methods:Two patients with brain stem tumors were treated with CT- and image fusion-guided 125I stereotactic brachytherapy.Results:By March 2003, the patients had been followed up for 47 and 13 months, respectively. In case 1, the tumor volume was 1.98 cm3 on the control CT, indicating a 65.5% shrinkage as compared to a target volume of 5.73 cm3 at the time of brachytherapy. In case 2, shrinkage was more distinct. After irradiation, the cyst volume was 0.16 cm3 on the control MRI, indicating a 97.4% shrinkage as compared to a target volume of 6.05 cm3 at the time of brachytherapy, i. e., the metastasis had virtually disappeared.Conclusion:CT- and image fusion-guided 125I stereotactic brachytherapy can be performed during the biopsy session. The procedure can be well planned dosimetrically and is surgically precise.Ziel:Beschreibung der interstitiellen Jod-125-(125I-)Brachytherapie bei der Behandlung von Hirnstammtumoren.Patienten und Methodik:Bei zwei Patienten mit Hirnstammtumoren wurde eine durch CT und Fusionsbild gesteuerte interstitielle 125I-Brachytherapie durchgeführt.Ergebnisse:Bis März 2003 betrugen die Nachuntersuchungszeiten der beiden Patienten 47 bzw. 13 Monate. Im ersten Fall lag das Tumorvolumen auf dem Kontroll-CT bei 1,98 cm3, was eine Schrumpfung um 65,5% anzeigte. Im zweiten Fall fiel diese Änderung deutlicher aus. Das Kontroll-MRT ergab eine Schrumpfung von 97,4%, d. h., die Metastase war praktisch verschwunden.Schlussfolgerung:Die durch CT und Fusionsbild gesteuerte interstitielle 125I-Brachytherapie lässt sich dosimetrisch gut planen, und die Methode ist chirurgisch präzise.

Pathological findings in cystic craniopharyngiomas after stereotactic intracavitary irradiation with yttrium-90 isotope.

Histopathological, ultrastructural and polyacrylamide gel electrophoretic examinations were carried out on biopsy, cyst fluid, surgical pathology and autopsy specimens obtained from 7 cystic craniopharyngioma cases before and after yttrium-90 silicate colloid (90Y) irradiation. Light microscopy revealed that the lining epithelial tumor cell layer of the cyst wall was destroyed, and scar tissue containing large amount of hyaline degenerated collagen bundles replaced it. Proliferative postirradiation vasculopathy was also demonstrated in the cyst wall following 90Y installation. Electrophoretic property of cyst fluid was similar to the normal human serum. Considering that scar tissue has a certain propensity to shrink, the fibrosis in the cyst wall together with destruction of neoplastic epithelium and vascular changes might explain diminished fluid production and cyst volume reduction after 90Y treatment.

Tissue Response to Iodine-125 Interstitial Brachytherapy of Cerebral Gliomas

The purpose of this study was to investigate histopathological changes and the role of the microglia/macrophage cell system in the therapeutic effect of iodine-125 (125I) interstitial brachytherapy on cerebral gliomas. Out of a series of 60 cases harboring cerebral astrocytomas and other brain tumors treated with 125I interstitial brachytherapy, autopsy material was available in 10 cases between 0.75 and 60 months after irradiation. The patients were treated with 60-Gy maximum doses at the tumor periphery. Besides the routine HE and Mallorys PTAH trichrome staining, immunohistochemical reactions were carried out for CD15, CD31, CD34, CD45, CD68 (PG-M1), CPM, HAM 56 and HLA-DR antigens to study immunological characteristics of the reactive cell population around gliomas after 125I treatment. The present immunohistochemical study demonstrated that the early lesions following 125I interstitial brachytherapy of gliomas are characterized by migrating macrophages apparently concerned with the removal of necrotic debris. The established phase of reactive zone around the necrotic center disclosed a narrow inner rim of microglial accumulation, and a broad outer area consisting of astrocytic gliosis, vascular proliferation, activated microglia and infiltration by macrophages. In the burned-out phase, the necrosis undergoes liquefaction, the microglial rim is replaced by end-stage macrophages, and the reactive zone is transformed into astrocytic gliosis, which can be considered as equivalent to scar tissue formed around necrosis outside of the central nervous system.

CT-Guided Unilateral Thalamotomy with Macroelectrode Mapping for the Treatment of Parkinson's Disease

Summary.Summary.Objective: To evaluate the effect of unilateral thalamotomy in patients with Parkinsons disease.Methods: The junction of the ventralis oralis posterior and ventralis intermedius nuclei targeted under CT-guidance, and confirmed by impedance recording and macrostimulation.Results: At the 6-month assessment the tremor has been completely abolished in 37 patients (82.2%), and reduced in 6 patients (13.3%). The Unified Parkinsons Disease Rating Scale tremor score decreased by 92.5%, rigidity improved by 65.9%. Axial symptoms and bradykinesia showed smaller improvement. The levodopa and anti-cholinergic medication significantly reduced. An improvement in the quality of life measured by the Parkinsons Disease Questionnaire (PDQ-39) has been observed. The dimensions of mobility, activities of daily living, emotional well being, and stigma were significantly (P<0.05) better, other changes were not significant. The single index improved from 47.8±7.8 to 28.9±6.3. Transient complications noted in 9 patients (20%), mild persistent morbidity observed in 3 patients (6.7%). At the 1, 2 and 3-year follow-up neither contralateral tremor, rigidity, nor bradykinesia progression was statistically significant.Conclusions: CT-guided thalamotomy with macro-electrode mapping provides a safe, effective and long lasting control of tremor and rigidity, reduces the need for medication, and improves the quality of life.

Image Fusion-Guided Stereotactic Iodine-125 Interstitial Irradiation of Inoperable and Recurrent Gliomas

Between 1996 and 2004, 27 patients with low grade gliomas (WHO grade I-II), 10 patients with WHO grade III gliomas and 6 patients with glioblastoma multiforme (WHO grade IV) were treated with stereotactic brachytherapy using low-dose rate iodine-125 (125I) isotope seeds at the Department of Neurosurgery, St. Johns Hospital, Budapest, Hungary. In all 43 cases, brachytherapy was used for surgically inoperable gliomas: in 32 cases for recurrent gliomas and in 11 cases as a primary treatment. Results of this study suggest that 125I brachytherapy for inoperable and recurrent gliomas is an effective method and offers a chance for longer-term survival.

Comparison of 125I Stereotactic Brachytherapy and LINAC Radiosurgery Modalities based on Physical Dose Distribution and Radiobiological Efficacy

Abstract Viola, A., Major, T. and Julow, J. Comparison of 125I Stereotactic Brachytherapy and LINAC Radiosurgery Modalities based on Physical Dose Distribution and Radiobiological Efficacy. Radiat. Res. 165, 695–702 (2006). The goal of this study was to make a comparison between stereotactic brachytherapy implants and linear accelerator-based radiosurgery of brain tumors with respect to physical dose distributions and radiobiological efficacy. Twenty-four treatment plans made for irradiation of brain tumors with low-dose-rate 125I brachytherapy and multiple-arc LINAC-based radiosurgery were analyzed. Using the dose–volume histograms and the linear-quadratic model, the brachytherapy doses were compared to the brachytherapy-equivalent LINAC radiosurgery doses with respect to the predicted late effects of radiation on normal brain tissue. To characterize the conformity and homogeneity of dose distributions, the conformal index, external volume index, and relative homogeneity index were calculated for each dose plan and the mean values were compared. The average tumor volume was 5.6 cm3 (range: 0.1–19.3 cm3). At low doses, the calculated radiobiological late effect on normal tissue was equivalent for external-beam and brachytherapy dose delivery. For brachytherapy at doses greater than 30 Gy, the calculated equivalent dose to normal tissues was less than for external-beam radiosurgery. However, the dose-calculated homogeneity was better for the LINAC radiosurgery, with a mean relative homogeneity index of 0.62 compared to the calculated value of 0.19 for the brachytherapy (P = 0.0002). These results are only predictions based on calculations concerning normal tissue tolerance. More data and research are needed to understand the clinical relevance of these findings.