• Journal of Korean Neurosurgical Society
• /
• v.40 no.5
• /
• pp.342-345
• /
• 2006

Objective : Gamma Knife Surgery[GKS] for the management of pineal region tumors is challengeable strategy as direct access to this area is not easy. The experiences of pineal region tumor patients treated with GKS were analyzed to evaluate the effectiveness. Methods : Seven patients with tumors in the pineal region were treated with GKS between September 1998 and May 2005. The histological diagnosis were pineal parenchymal tumor [2 patients], low-grade astrocytoma [2 patients], immature teratoma [1 patient], and choriocarninoma [1 patient]. One patient was diagnosed as metastatic brain tumor based on histological diagnosis for primary site and brain imaging study. The median marginal dose was 15Gy [range; $11{\sim}20$] at the 50% isodose line. The median target volume was $2.5cm^3$ [range; $0.8{\sim}12.5$]. The median clinical follow up period was 29 months [range; $13{\sim}93$] and the median radiological follow up period was 18 months [range; $6{\sim}73$]. Results : Tumor volume measured in follow-up images showed reduction in six patients, disappearance in one. No adverse effect due to GKS was found during the follow-up period. The performance status was preserved in all patients except one who died due to progression of primary cancer in spite of controlled metastatic brain lesion. Conclusion : Gamma Knife Surgery can be applied to pineal region tumors irrespective of their histology whenever surgery is not indicated.

• The Journal of Korean Medicine
• /
• v.30 no.5
• /
• pp.157-162
• /
• 2009

Objectives: The purpose of this study is reporting the possibility of the treatment of metastatic brain tumors with allergen removed Rhus verniciflua Stokes (aRVS) after gamma knife radiosurgery. Methods: A patient with lung cancer felt a headache about one year after conventional therapies, and metastatic brain tumors were diagnosed. He received gamma knife radiosurgery twice but refused to get more conventional therapies afterwards. So he has been treating with aRVS since then. Results: During 143 weeks of administration of aRVS, the size of brain masses has decreased continuously without extracranial metastasis and the patient has maintained a good performance status. Conclusions: This report suggests that aRVS may play a therapeutic role in the treatment of metastatic brain tumors. Further studies will be needed to determine the effect of aRVS on metastatic brain tumors.

• The Journal of Internal Korean Medicine
• /
• v.43 no.5
• /
• pp.838-853
• /
• 2022

Objectives: The purpose of this study is to report the case of a patient with recurrent L858R mutation non-small-cell lung cancer with brain metastases treated with erlotinib and traditional Korean medicine after gefitinib failure. Methods: The patient was treated with erlotinib beginning in November 2021, and gamma knife surgery was performed on November 8, 2021. The dose of erlotinib was 150 mg/day every four weeks. At the same time, the patient was treated with traditional Korean medicine. Tumor size and cerebral edema were measured using computed tomography and magnetic resonance imaging, respectively. Adverse events were evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0. Results: After treatment with erlotinib and traditional Korean medicine for six months, the extent of the growing nodule in the right upper lobe decreased during the first three months and remained stable for the following three months. Peritumoral edema showed an increase three months after gamma knife surgery, but partial improvement of cerebral edema was confirmed with additional traditional Korean medicine six months after gamma knife surgery. The symptoms of discomfort and physical activity gradually improved. Conclusions: This case study suggests that the combination of EGFR-TKI and traditional Korean medicine may contribute to a reduction in tumor size and cerebral edema while improving quality of life.

• Journal of Korean Neurosurgical Society
• /
• v.57 no.2
• /
• pp.127-130
• /
• 2015

A 59-year-old female presented with progressive right proptosis, chemosis and ocular pain. An imaging work-up including conventional catheter angiography showed a right-sided dural arteriovenous fistula of the cavernous sinus, which drained into the right superior petrosal sinus, right superior ophthalmic vein, and right inferior ophthalmic vein, and cortical venous reflux was seen via the right petrosal vein in the right posterior fossa. After failure of transvenous embolization, the patient underwent Gamma Knife radiosurgery (GKRS). At one month after GKRS, she developed increasing ocular pain and occipital headache. Repeat angiography showed partial obliteration of the fistula and loss of drainage via the superior and inferior ophthalmic veins with severe congestion, resulting in slow flow around the right cerebellar hemisphere. Prompt transarterial embolization relieved the patient's ocular symptoms and headache. We report on a case of paradoxical exacerbation of symptoms resulting from obstruction of the venous outflow after GKRS for treatment of a dural arteriovenous fistula of the cavernous sinus.

• Journal of Korean Neurosurgical Society
• /
• v.44 no.2
• /
• pp.67-71
• /
• 2008

Objective : Radiosurgery may be contraindicated for lesions adjacent to the optic pathways because of the substantial risk of visual complication. Multisession radiosurgery has been tried as a compromise between single session radiosurgery and fractionated radiotherapy. The purpose of this study is to evaluate the outcomes of multisession gamma knife radiosurgery (GKRS) in 22 patients with perioptic lesions of benign pathology. Methods : In all 22 cases, the lesions were within 1 mm of the optic apparatus and were therefore not considered suitable for single session radiosurgery. Radiation was delivered in 3 to 4 fractions with a median cumulated marginal dose of 20 Gy (range, 15-20 Gy). Results : During a mean follow-up of 29 months (range, 14-44 months), tumor control was achieved in 21 patients. Visual function improved in 7 patients, remained unchanged in 14 patients, and deteriorated in 1 patient with tumor progression. No other complication was observed. Conclusion : This preliminary result supports the idea that multisession GKRS may be an effective and safe alternative for treatment in perioptic lesions that are unsuitable for single session radiosurgery.

• Proceedings of the Korean Society of Medical Physics Conference
• /
• 2002.09a
• /
• pp.300-301
• /
• 2002

Of many modalities for measuring output factor, we measured the outputs of 18mm, 14mm, 8mm and 4mm helmet in Gamma knife using ion chambers and a Gafrcromic MD-55 film and normalized the outputs of four helmets the one of a 18mm helmet. Ion chambers used for this paper were a PR-05P and a PinPoint having a volume of 0.07cc and 0.015cc respectively. The recommended output factors from a manufacture were 1, 0.984, 0.956, and 0.87. For PR-05P, the output factor of 14mm helmet showed a good agreement, but the ones of 8mm and 4mm helmet showed the difference of 4.6% and 47% respectively. For PinPoint, The output factors of 14mm and 8mm helmet showed a good agreement, but the one of a 4mm helmet showed a difference of 18%. The Gafcromic MD-55, however, showed a good agreement for all helmets.

• Journal of Korean Neurosurgical Society
• /
• v.39 no.2
• /
• pp.96-101
• /
• 2006

Objective : The authors assess the long term effectiveness of gamma knife radiosurgery[GKS] for remnant or recurred craniopharyngiomas on tumor control and possibly set proper radiation dose for tumor control with utmost preservation of the adjacent structures. Methods : Sixteen GKS were done in 14 patients with recurred or remnant craniopharyngiomas after surgery. Mean follow up duration was 44.2 months [range $11.3{\sim}123.6\;months$]. Follow up MR imagings were analyzed. Results : Mean tumor volume was $3.6cm^3$ [range $0.6{\sim}18cm^3$] and mean margin dose was 12.2Gy [range $8{\sim}22.4Gy$]. Tumor control was achieved in 87.5% [14 of 16 tumors] which were either solid or cystic in nature. Dose to optic apparatus was mean 7.9Gy and no radiation related complications were observed. Conclusion : GKS seems to be effective treatment modality for craniopharyngiomas regardless of nature of tumor whether it is cystic or solid. Dose of 8 to 8.5Gy may be sufficient to achieve long term tumor control for remnant or recurred craniopharyngiomas.

• Korean Journal of Head & Neck Oncology
• /
• v.30 no.2
• /
• pp.119-122
• /
• 2014

Rhabdomyosarcoma is the most common sarcoma in children less than 15 years of age. Two major histological subtypes are embryonal and alveolar. Embryonal rhabdomyosarcoma is diagnosed by immunopathology and treatments require coordinated management plans that include surgery, chemotherapy, and usually radiotherapy. 8-month-old male infant visited with swelling in left parotid area. Computed tomography scan showed a heterogeneous mass in the left parotid area and the result of fine-needle aspiration cytology was suspicious malignancy. Left total parotidectomy was performed and CSF leakage was noted and repaired. Confirmed by positive reactions to desmin and myogenin, the diagnosis was embryonal rhabdomyosarcoma. On postoperative brain MRI, extension along the meninges was noted and for treatment, chemotherapy and gamma knife radiosurgery were done. Five years after initial surgical resection(3 years and 10 months after completion of chemotherapy and gamma knife radiosurgery), the child did not show any evidence of local recurrence or distant metastasis.

• Progress in Medical Physics
• /
• v.31 no.3
• /
• pp.63-70
• /
• 2020

Stereotactic radiosurgery is one of the most sophisticated forms of modern advanced radiation therapy. Unlike conventional fractionated radiotherapy, stereotactic radiosurgery uses a high dose of radiation with steep gradient precisely delivered to target lesions. Lars Leksell presented the principle of radiosurgery in 1951. Gamma Knife^® (GK) is the first radiosurgery device used in clinics, and the first patient was treated in the winter of 1967. The first GK unit had 179 cobalt 60 sources distributed on a hemispherical surface. A patient could move only in a single direction. Treatment planning was performed manually and took more than a day. The latest model, Gamma Knife^® Icon^TM, shares the same principle but has many new dazzling characteristics. In this article, first, a brief history of radiosurgery was described. Then, the physical properties of modern radiosurgery machines and physicists' endeavors to assure the quality of radiosurgery were described. Intrinsic characteristics of modern radiosurgery devices such as small fields, steep dose distribution producing sharp penumbra, and multi-directionality of the beam were reviewed together with the techniques to assess the accuracy of these devices. The reference conditions and principles of GK dosimetry given in the most recent international standard protocol, International Atomic Energy Agency TRS 483, were shortly reviewed, and several points needing careful revisions were highlighted. Understanding the principles and physics of radiosurgery will be helpful for modern medical physicists.

• Journal of Korean Neurosurgical Society
• /
• v.65 no.6
• /
• pp.861-867
• /
• 2022

Objective : High-dose radiation is well known to induce and modulate the immune system. This study was performed to evaluate the correlation between clinical outcomes and changes in natural killer cell activity (NKA) after Gamma Knife Radiosurgery (GKS) in patients with brain cancer. Methods : We performed an open-label, prospective, cross-sectional study of 38 patients who were treated with GKS for brain tumors, including metastatic and benign brain tumors. All of the patients underwent GKS, and blood samples were collected before and after GKS. NKA was measured using an enzyme-linked immunosorbent assay kit, to measure interferon-gamma (IFNγ) secreted by ex vivo-stimulated NK cells from whole blood. We explored the correlations between NK cell-produced IFNγ (NKA-IFNγ) levels and clinical parameters of patients who were treated with GKS for brain tumors. Results : NKA-IFNγ levels were decreased in metastatic brain tumor patients compared to those with benign brain tumors (p<0.0001). All the patients who used steroid treatment to reduce brain swelling after GKS had an NKA-IFNγ level of zero except one patient. High NKA-IFNγ levels were not associated with a rapid decrease in brain metastasis and did not increase after GKS. Conclusion : The activity of NK cells in metastatic brain tumors decreased more than that in benign brain tumors after GKS.