Search

Application of radiosurgery to the newly diagnosed or post-operative residual perioptic lesions has been proved to improve tumor control. However, risk of vision injury induced by radiosurgery may increase substantially if the radiation dose is too high or tumor is close to the optic apparatus. The purpose of this study was to evaluate the safety and the effectiveness of fractionated stereotactic radiosurgery (FSRS) for perioptic tumors. We retrospectively analyzed 60 consecutive patients with 53 meningiomas and 7 schwannomas treated with FSRS between October 2007 and February 2020. We administered a marginal dose of 6–7 Gy (mean 6.8 Gy) per fraction and delivered 3 fractions in 3 consecutive days. The median tumor volume was 6.31 cm3 (range 0.3–58.23 cm3). The mean minimum lesion-optic distance (MLOD) is 0.85 mm (range 0–3 mm). After mean follow-up period of 69.6 months (range 6.82–156.32 months; median 58.9 months), the tumor control rates at 1, 3, 5, 8 and 13 years were 98.3%, 93.4%, 90.60%, 88.4% and 88.4%, respectively. Four out of the 60 tumors (6.7%) experienced a transient volume increase after FSRS. None of the patients developed visual impairment related to radiation induced optic neuropathy (RION) after FSRS. In conclusion, FSRS offers an alternative treatment option in treating perioptic meningiomas and schwannomas with acceptable tumor control rates and good visual preservation in the present study.

Background This report presents the third case of trochlear schwannoma arising from the pineal region and the first case to be resected using a paramedian infratentorial supracerebellar approach. Schwannomas of cranial nerves have traditionally been thought to arise from the transitional point where the axonal envelopment switches from glial cells to Schwann cells; however, recent temporal bone histopathologic evidence from vestibular schwannomas challenges this view. Of the 38 cases of pathology-confirmed trochlear schwannoma in the literature, there are only 2 cases arising from the pineal region, where the nerve sheath transition zone is located. Here, we discuss an unusual case of trochlear schwannoma arising from this transition zone. Case Description A 65-year-old man was admitted to our institute after a traffic accident. He complained of headache and dizziness, and a computed tomography scan revealed an isodense mass in the pineal region with obstructive hydrocephalus. Magnetic resonance imaging with contrast showed an enhancing mass in the pineal region. The tumor was subtotally resected using a paramedian infratentorial supracerebellar approach, and pathology confirmed the diagnosis of trochlear schwannoma. Conclusions Trochlear schwannoma should be considered when a mass is identified in the pineal region. This diagnosis should still be entertained for mass lesions along the free tentorial edge because the tumor may arise distant from the glial-Schwann transition zone located by the dorsal midbrain. We propose a treatment algorithm for this rare tumor that seeks to maximize functional outcome.

Introduction: The purpose of this study is to determine the success and complication rates of linear accelerator (LINAC)-based radiosurgery (X-knife) for indirect carotid-cavernous fistulas (CCFs). Materials and Methods: This retrospective study was performed at the Department of Radiosurgery, Chang Gung Memorial Hospital, Taiwan, and reviewed data from May 2006 to May 2018. Thirteen patients with CCF who were treated with stereotactic radiosurgery were included, and side, volume, pathological type, origin, location, postoperative regression, and recurrence rate were evaluated with postradiotherapy. Patients were either followed up with contrast magnetic resonance imaging or angiography. Radiosurgery was considered successful if the patients' clinical symptoms improved with radiological remission or if there was a reduction in CCF flow in angiography. Results: Of the 11 patients, three (27.3%) received transarterial embolization (TAE) before radiosurgery. Successful radiological outcomes were seen in 10 (90.9%) patients, and the remaining one patient (9.1%) had stationary disease with no reduction in CCF flow. Ten patients (90.9%) had improved clinical symptoms; however, one patient (9.1%) was complicated with iatrogenic blindness after TAE treatment. No acute or subacute transient postradiation changes, optic nerve injuries, or brainstem radionecrosis were noted in any of the patients. Conclusions: In this study, LINAC-based radiosurgery for CCF was found to be an effective, safe, and successful treatment alternative to TAE treatment in patients with indirect CCF. The risk of postradiotherapy complications was low, and obliteration and regression rates were high.

Atypical and malignant meningiomas are rare. Our aim was to examine the treatment outcomes following surgical resection, and analyze associations between clinical characteristics and overall survival (OS) or relapse free survival (RFS). 102 patients with atypical or malignant meningiomas underwent microsurgical resection between June 2001 and November 2009 were analyzed retrospectively. We compared demographics, clinical characteristics, treatment, and complications. The five-year and ten-year overall survival rates were 93.5% and 83.4%, respectively. Three factors significantly reduced OS: Malignant meningiomas (p

The aim of this study was to investigate the efficacy of linear accelerator (LINAC)-based radiosurgery in the treatment of acoustic neuromas. In this retrospective study, we enrolled 75 patients with non-neurofibromatosis type 2 acoustic neuromas who were followed-up for more than 5 years. The 75 patients were divided into 3 groups: patients with a newly diagnosed tumor; those with a residual tumor; and those with a recurrent tumor. The average follow-up period was 97.8 months. The overall tumor progression-free rate was 92%, and corresponding rates among those with newly diagnosed tumors was 100%, residual tumors was 84.4%, and recurrent tumors was 92.8% (p = 0.028). Lesion localization using CT scans correlated with a higher tendency for tumor progression than lesion localization using CT–MRI fusion images (15.6% versus 2.4%, respectively). Residual tumors treated with radiosurgery have a higher progression rate, and careful lesion localization using CT–MRI image fusion is required.

Background The annual hemorrhage rate of intracranial cavernous malformation (CM) is reported to range from 0.23% to 1.1%. Because of the low hemorrhage rate, operating on a deep symptomatic lesion with or without hemorrhage is considered controversial. For the prevention of hemorrhage, radiosurgery is an alternative method, targeting smaller lesions and delivering higher doses of radiation. Linear accelerator (LINAC) radiosurgery, aside from the gamma knife (GK), is not often discussed in the treatment of CM. Patients and methods From 1995 to 2005, 30 patients presenting with hemorrhage or seizures, aged 14–79 years (mean 24.0 years) with single (27 patients) or multiple (three patients) CMs received LINAC radiosurgery at our institute. Six patients received LINAC radiosurgery following craniotomy for residual lesions revealed by the follow-up MRI. The temporal lobe was the most common site for CM in this series ( n =8), followed by the brain stem ( n =7). Thirty patients received 34 radiosurgery treatments with peripheral doses ranging from 800cGy to 2200cGy. The mean follow-up time was 59.9 months (range 1–122 months). Results One patient re-bled post-radiosurgery (0.67% in 149.75 observation-years). Two patients had asymptomatic post-LINAC edema (6.7%). Those three patients were symptom-free during the follow-up period. Conclusion We suggest that LINAC radiosurgery is a relatively safe technique for treating deep or residual CM, although the actual effectiveness for CM obliteration is not known.

We report the case of a 15-year-old girl with amenorrhea and a several-week history of headache. After the diagnosis of membranous obstruction of the foramen of Magendie suggested by MRI, suboccipital craniotomy for removal of the membrane was carried out. The patient made an excellent postoperative recovery, and postoperative phase-contrast MRI demonstrated patent cerebrospinal fluid (CSF) pathways at the level of the foramina of Magendie and Luschka. We believe that this case is of interest because of the unequivocal evidence on MRI studies of the occlusion of the foramen of Magendie preoperatively, and because of the dramatic postoperative MRI findings demonstrating the effectiveness of the surgical procedure both in terms of ventricular size and CSF flow characterization.

Background: Arteriovenous malformation (AVM) is one of the cerebrovascular diseases that bear a high risk of hemorrhage. The treatment modalities include microsurgical resection, endovascular embolization, stereotactic radiosurgery, or combinations that vary widely. Several large series have been reported, while data from Asian populations were few. The aim of this study was to examine the efficacy of linear accelerator stereotactic radiosurgery (LINAC SRS) for the treatment of intracranial AVMs, to evaluate the hemorrhage rate and to analyze associated factors. Methods: One hundred and sixteen patients with AVM were treated with LINAC SRS in a single institute between September 1994 and May 2005 and were retrospectively evaluated. The demographics of patients, clinical characteristics of AVM, the treatment modalities, and the parameters of the LINAC SRS were analyzed. Delayed toxicity and hemorrhage rate after treatment were also evaluated. The AVM obliteration and bleed rates were calculated using the Kaplan-Meier method and Cox regression analyses. Results: The efficacy rate with total obliteration after treatment was 81.9% (95 of 116 patients). The median interval to achieve total obliteration was 49 months. Microsurgical resection combined with SRS for residual AVMs achieved better obliteration rates compared to SRS alone (statistically significant, p = 0.001), while no significant difference was found between the embolization group and the group with no prior treatment (p = 0.895). The Spetzler-Martin grade of AVM is a relative factor of obliteration, higher grades resulting in a worse outcome (p = 0.009). Obliteration was significantly influenced by AVM volume in univariate analysis (p = 0.034), and volume 3 contributed to improved obliteration (p = 0.01). There was no statistically significant difference in the hemorrhagic rate and the complication rate between ruptured and unruptured AVMs, while the unruptured group had a higher obliteration rate (p = 0.024). The annual hemorrhage rate after LINAC SRS treatment was 1.9%. The bleeding rate was 3.3% in the first year after radiosurgery, 2.1% in the second year, 1.9% between the second and fifth year, and 1.5% between the fifth and tenth year. Patients with hemorrhagic events before radiosurgery appeared to have a higher rebleeding risk during the latency period. Twenty-three patients (19.8%) had late adverse effects with regard to posttreatment radiological follow-up, but only 1 (0.8%) had newly developed neurological deficits. Conclusion: LINAC SRS achieved a high obliteration rate and reduced the risk of hemorrhage effectively in ruptured and unruptured intracranial AVMs. Prior microsurgical resection provided better outcome, while embolization showed no benefit. Adverse effects after treatment are acceptable and require long-term follow-up.

Radiosurgery has been proven to be an effective treatment for residual or recurrent pituitary adenomas after surgery. However, it causes severe complications when the optic apparatus is irradiated over the tolerance dose. In this study, we analyzed the feasibility of fractionated stereotactic radiosurgery to treat pituitary tumors close to the optic apparatus. Thirty-four patients from June 2006 to June 2011 with recurrent or residual pituitary adenomas close to (

Reconstruction of cranial defects can be reasonably considered a failure if an aesthetically obvious cranial contour deformity persists after surgery. Such unsatisfactory outcome often results from variable resorption of bone grafts or infection, requiring removal of implant. In considering further treatment for such failed cases, the use of alloplastic implants is frequently warned as imprudent due to their theoretically increased potential for infection; however, the validity of such caution has never been substantiated. We describe a user-friendly, time- and cost-effective method of producing prefabricated methyl methacrylate implants for the reconstruction of cranial defects, using readily available computer-aided design and computer-aided manufacture facilities. This method was carried out in 31 patients who presented with persistent cranial defects after previously failed cranioplasty. The efficacy of this technique and the clinical outcome of the patients in this series were analysed. All implants produced a precise fit, with a reduction in operating time and satisfactory cosmesis having been achieved. Infection that required removal of implant occurred in three patients (9.7%), and one patient developed a dural tear, requiring repair. Customised fabricated alloplastic implants provide a safe, accurate and efficient way of restoring normal cranial contours in patients with cranial defects who have had previous failed cranioplasties.

Background: Epilepsy is the most common symptom of cavernoma. Although microsurgery is the mainstay treatment for epileptogenic cavernoma, this procedure may cause severe complications for some lesions. This report aimed to study if linear accelerator (LINAC) radiosurgery was an alternative treatment modality for epileptogenic cavernoma. Methods: In this retrospective study, 29 patients were diagnosed with epileptogenic cavernomas from September 1995 to March 2005. Fifteen patients were treated with surgical excision and 14 with LINAC radiosurgery. The evaluation of epilepsy control was according to Engel’s classification. Results: In the surgical group, 13 (86.7%) of 15 patients had a class I seizure-free outcome. In the radiosurgery group, class I control was achieved in 9 (64.3%) of 14 patients. However, there was no significant difference in the results of treatment between the two groups. Conclusions: LINAC radiosurgery is an alternative treatment for epileptogenic cavernomas, especially when the lesions are located in the central regions or eloquent areas of the brain.

Purpose To evaluate outcomes of total subcondylar excision of mandibular condylar osteochondroma. Patients and Methods Two adult patients presented with progressive facial asymmetry, jaw deviation, and limited mouth opening. Computed tomogram (CT) showed a large osseous tumor arising from the right condyle occupying the subtemporal space in these patients. Complete surgical excision was performed without condyle reconstruction. The pathology report indicated osteochondroma. Patients were followed for an average of 5 years. Results Long-term evaluation showed restoration of dento-occlusal function and facial appearance. Follow-up CT showed a partly regenerated and remodeled condyle. Patients' chewing function was acceptable, but predominantly on the lesion side. Conclusions Condylar osteochondroma caused jaw deviation and joint dysfunction. Complete surgical excision achieved an adequate long-term outcome, but condylar reconstruction is advisable.