Abstract Background The coexistence of Glioblastoma Multiforme (GBM) and Arteriovenous Malformation (AVM) is rarely reported in literature. Additionally, there is a paucity of data surrounding the simultaneous presentation of Glioblastoma Multiforme (GBM) with intracranial aneurysms. In the English literature, the concurrence of these three intracranial lesions has never been reported. Regarding our case, we present a case of an Internal Carotid Artery (ICA) aneurysm that occurred in a patient with coexisting GBM and AVM. In addition, we discuss the current literature relating to this unique combination of medical conditions. Case Presentation The 44-year-old female was presented to our hospital experiencing intermittent headaches and dizziness. Magnetic Resonance Imaging (MRI) revealed a heterogeneously enhanced mass with peri-focal edema at the right temporal lobe. Upon additional computed tomographic angiography study, the presence of AVM nidus at the right temporal-parietal occipital region was noted. Moreover, the image study also demonstrated a right ICA aneurysm. After surgery, histopathological examination demonstrated GBM and AVM in the separately resected lesion specimen. Furthermore, we expected that the ICA aneurysm would reduce in size after removal of the ipsilateral AVM and glioblastoma. Unfortunately, the postoperative digital subtraction angiography revealed only sparse change in the right ICA aneurysm, resulting in the patient still needing to receive intervention involving flow diverter stent placement. Conclusions In this case, we discuss the current literature relating to this unique combination of medical conditions. The causality and correlation of this presentation remains uncertain. With regards to our case, the pre-surgical image survey provided us with much support towards making critical decisions. Surgery surrounding the removal of simultaneously coexisting AVM and GBM is always a challenging task due to the potential risk of massive intraoperative bleeding.
OBJECTIVE Stereotactic radiosurgery (SRS) is an important alternative management option for patients with small- and medium-sized vestibular schwannomas (VSs). Its use in the treatment of large tumors, however, is still being debated. The authors reviewed their recent experience to assess the potential role of SRS in larger-sized VSs. METHODS Between 2000 and 2014, 35 patients with large VSs, defined as having both a single dimension > 3 cm and a volume > 10 cm3, underwent Gamma Knife radiosurgery (GKRS). Nine patients (25.7%) had previously undergone resection. The median total volume covered in this group of patients was 14.8 cm3 (range 10.3-24.5 cm3). The median tumor margin dose was 11 Gy (range 10-12 Gy). RESULTS The median follow-up duration was 48 months (range 6-156 months). All 35 patients had regular MRI follow-up examinations. Twenty tumors (57.1%) had a volume reduction of greater than 50%, 5 (14.3%) had a volume reduction of 15%-50%, 5 (14.3%) were stable in size (volume change < 15%), and 5 (14.3%) had larger volumes (all of these lesions were eventually resected). Four patients (11.4%) underwent resection within 9 months to 6 years because of progressive symptoms. One patient (2.9%) had open surgery for new-onset intractable trigeminal neuralgia at 48 months after GKRS. Two patients (5.7%) who developed a symptomatic cyst underwent placement of a cystoperitoneal shunt. Eight (66%) of 12 patients with pre-GKRS trigeminal sensory dysfunction had hypoesthesia relief. One hemifacial spasm completely resolved 3 years after treatment. Seven patients with facial weakness experienced no deterioration after GKRS. Two of 3 patients with serviceable hearing before GKRS deteriorated while 1 patient retained the same level of hearing. Two patients improved from severe hearing loss to pure tone audiometry less than 50 dB. The authors found borderline statistical significance for post-GKRS tumor enlargement for later resection (p = 0.05, HR 9.97, CI 0.99-100.00). A tumor volume ≥ 15 cm3 was a significant factor predictive of GKRS failure (p = 0.005). No difference in outcome was observed based on indication for GKRS (p = 0.0761). CONCLUSIONS Although microsurgical resection remains the primary management choice in patients with VSs, most VSs that are defined as having both a single dimension > 3 cm and a volume > 10 cm3 and tolerable mass effect can be managed satisfactorily with GKRS. Tumor volume ≥ 15 cm3 is a significant factor predicting poor tumor control following GKRS.
Background: There are several methods for treating tic douloureux including Gamma Knife stereotactic radiosurgery (GKSR), gasserian ganglion percutaneous technique and microvascular decompression (MVD). MVD via the posterior fossa has become the standard treatment for trigeminal neuralgia (TN). This microsurgical procedure has been proven safe in experienced hands and its effectiveness rate is as high as 98%. The aim of this paper is to share the authors' personal experience, from the standpoint of operative technique, with those who are contemplating performing or who are already performing this kind of surgery. Materials and Methods: Over the past two decades, among 349 patients (including three with failed GKSR) with typical TN, 288 received MVD, 39 received partial sensory rhizotomy and 22 received MVD combined with partial sensory rhizotomy. With the patient in a lateral position, a small retrosigmoid craniectomy was used to approach the cerebellopontine angle (CPA) via the lateral supracerebellar route. Exploration and identification of the offending artery (arteries) in contact with the whole nerve, at any point, not merely the root entry zone (REZ), were carefully carried out. Transposition of the offending vessel (vessels) away from the nerve was the main decompression method, followed by Teflon felts interpositioned between the two structures. Results: All patients were evaluated within 1 week of operation. Excellent (90.9%) and good (4.6%) clinical outcomes were achieved in 333 patients; partial pain relief was achieved in 10 patients; and little or no pain relief was achieved in 6 patients. All 6 patients who failed to respond positively to the initial surgery underwent partial sensory rhizotomy within 1 week of evaluation to relieve the pain. Conclusion: MVD is generally accepted as the gold standard for first line treatment of TN, especially in younger patients who are refractory to medication. The anatomical approach that we have adopted is described in detail.
Peritumoral edema may be a prohibitive side effect in treating large incidental meningiomas with stereotactic radiosurgery. An approach that limits peritumoral edema and achieves tumor control with SRS would be an attractive management option for large incidental meningiomas.This is a retrospective cohort study of patients with large incidental meningiomas (≥2 mL in volume and/or 2 cm in diameter) treated with gamma knife radiosurgery (GKRS) between 2000 and 2019 in Taiwan and followed up for 5 years. The outcomes of a pathophysiological approach targeting the dural feeding artery site with a higher marginal dose (18-20 Gy) to enhance vascular damage and the parenchymal margin of the tumor with a lower dose (9-11 Gy) to reduce parenchymal damage were compared with those of a conventional approach targeting the tumor center with a higher dose and tumor margin with a lower dose (12-14 Gy).A total of 53 incidental meningiomas were identified, of which 23 (43.4%) were treated with a pathophysiological approach (4 cases underwent a two-stage approach) and 30 (56.7%) were treated with a conventional approach. During a median follow-up of 3.5 (range 1-5) years, tumor control was achieved in 19 (100%) incidental meningiomas that underwent a single-stage pathophysiological approach compared with 29 (96.7%) incidental meningiomas that underwent a conventional approach (log-rank test: p = 0.426). Peritumoral edema developed in zero (0%) incidental meningiomas that underwent a single stage pathophysiological approach compared to seven (23.3%) incidental meningiomas that underwent a conventional approach (log-rank test: p = 0.023).Treatment of large incidental meningiomas with a pathophysiological approach with GKRS achieves similar rates of tumor control and reduces the risk of peritumoral edema. GKRS with a pathophysiological approach may be a reasonable management strategy for large incidental meningiomas.
After falling from a height, a 29-year-old male patient developed a traumatic left subdural hematoma (SDH) with brain swelling and a midline shift to the right side, as well as a small epidural hematoma (EDH) (thickness: <1 cm) overlying a contralateral temporal linear fracture. A decompressive craniectomy for SDH evacuation and the placement of an intracranial pressure (ICP) monitoring device were performed. Because of uncontrollable ICP (>35 mmHg) 48 hours after surgery, a left, extended decompressive craniectomy was performed in combination with therapeutic hypothermia for 6 days, including rewarming for 3 days. The patient remained stable for several days. However, the patient developed sudden right pupil dilatation with an uncal herniation on Day 14. Computed tomography revealed a considerable enlargement of the contralateral EDH. An emergency craniectomy was performed for EDH evacuation. In this paper, we describe this rare case, in which the delayed expansion of the contralateral EDH occurred 14 days after the initial surgery, and discuss its clinical management and radiologic findings, in addition to reviewing the literature and presenting the possible mechanism of this complication.
We report a rare case of atheromatous plaque formation in the offending parent artery of a 39-year-old man 11 months after Gamma Knife stereotactic radiosurgery (GKSR) for trigeminal neuralgia (TN). Focal atheromatous changes to the parent vessel remote from the root entry zone (REZ) of the trigeminal nerve were discovered during rescue open surgery; this has seldom been reported. Our report suggests that younger male TN patients with hyperlipidemia who receive GKSR may have an increased risk of post-radiation atheromatous formation. A review of the literature is carried out together with a discussion of the possible mechanism by which this complication occurred.
Cellular density is a major factor responsible for changes in apparent diffusion coefficients (ADCs). The authors hypothesized that loss of tumor cells after Gamma Knife surgery (GKS) might alter ADC values. Magnetic resonance imaging, including diffusion-weighted (DW) imaging, was performed to detect cellular changes in brain tumors so that the authors could evaluate the tumor response to GKS as well as the efficacy of the procedure.The authors conducted a prospective trial involving 31 patients harboring solid or cystic vestibular schwannomas (VSs) that were treated with GKS. The patients underwent serial MR imaging, including DW imaging, before GKS and at multiple intervals following the procedure. The authors observed the patients over time, evaluating MR imaging findings and clinical outcomes at 6-month intervals. The ADCs were calculated from echo-planar DW images, and mean ADC values were compared at each follow-up.The mean follow-up period was 36.5 months (range 18-60 months). Imaging studies showed a reduction in tumor volume in 19 patients (61.3%) and tumor growth arrest in 9 patients (29%). In the remaining 3 patients (9.7%), tumor enlargement was documented at 18, 36, and 42 months. The mean ADC value before GKS for all solid VSs was 1.06 ± 0.17 × 10(-3) mm(2)/second, which significantly increased 6 months after GKS and continued to increase with time (p = 0.0086). The mean ADC value for treated solid tumors as of the last mean follow-up of 36 months (range 18-60 months) was 1.72 ± 0.26 × 10(-3) mm(2)/second (range 1.50-2.09 × 10(-3) mm(2)/second), which was significantly higher than that before GKS (p = 0.0001). Tumor volumes were positively related to ADC values (p = 0.03). The mean ADC value before GKS for all cystic VSs was 2.09 ± 0.24 × 10(-3) mm(2)/second (range 1.80-2.58 × 10(-3) mm(2)/second). The mean ADC value for treated cystic tumors as of the last mean follow-up of 38 months (range 18-48 months) was 1.89 ± 0.22 × 10(-3) mm(2)/second. In 3 patients harboring solid VSs, the tumor enlarged after GKS but the ADC values were higher than those before GKS. The authors considered these tumors to be controlled and continued follow-up in the patients.Apparent diffusion coefficient values may be useful for evaluating treatment results before any definite volume change is detected on imaging studies and for distinguishing radiation-induced necrosis from tumor recurrence in cases in which other imaging results are not definitive, as in cases of increased tumor volume or no volume change. The authors suggest that ADC measurements be included during routine MR imaging examinations for the evaluation of GKS results.
Background: Regulation requires periodic reconfirmation of the number of radioactive sources in Gamma Knife (GK). To comply with regulations, the total dose output (TDO) method, originally designed to verify amount of radiation received by patients, was adopted as a tool for source security. However, we suspect the TDO method may be unreliable in detecting small numbers of missing sources given that a 2% margin of error is allowed. We propose an alternate method using Gafchromic films to identify number of sources present. Method: To test the efficacy of the TDO method, we simulated real-life source loss by plugging up to 5 sources. TDO after plugging 0, 1, 2, 3, 4, and 5 sources were measured using GK 4C. Percentage change for each additional source plugged was computed. We then proceeded to test the film method. For GK 4C, 2 Gafchromic RTQA2 single sided films measuring 10 × 10 inch were first halved to 5 × 10 inch films. Four 5 × 10 inch films were then adhered to the inner surface of the 18 mm collimator. For GK Perfexion, 2 Gafchromic EBT3 double sided films measuring 10 × 12 inches were combined and rolled into a cone film and adhered to the collimator during installation. In both cases, the films were exposed to 0.5 Gy. Results: TDO was inversely related to the number of source plugged. TDO decreased by more than 2% after 5 plugs. The film method was able to outline all 201 and 192 Co sources for GK4Cand Perfexion respectively. Conclusion: A single lost source is hard to detect using the TDO method given that at least 5 sources had to be lost before the change in TDO will exceed the margin of error (±2%). The film method bypasses this limitation and offers an easy alternative to accurately obtain the number of sources.
'/%3e%3cuse xlink:href='%23a' transform='rotate(60)'/%3e%3ccircle r='17' fill='%23000095'/%3e%3ccircle r='15' fill='%23fff'/%3e%3c/svg%3e)