bluuebunny/crossref_metadata_2025 huggingface dataset:
Gamma knife surgery for cancer pain—pituitary gland—stalk ablation: a multicenter prospective protocol since 2002
Authors: Hayashi Motohiro , Taira Takaomi , Chernov Mikhail , Fukuoka Seiji , Liscak Roman , Yu Chung Ping , Ho Robert T. K. , Regis Jean , Katayama Yoko , Kawakami Yoriko , Hori Tomokatsu
Published: November 2018

Object. The authors have treated intractable pain, particularly cancer pain related to bone metastasis, with various protocols. Cancer pain has been treated by gamma knife radiosurgery (GKS), targeted to the pituitary gland—stalk, as an alternative new pain control method. The purpose of this study was to investigate a prospective multicenter protocol to prove the efficacy and the safety of this treatment.

Methods. Indications for patient inclusion in this treatment protocol were: 1) pain related to bone metastasis; 2) no other effective pain treatment options; 3) general condition rated as greater than 40 on the Karnofsky Performance Scale; 4) morphine effective for pain control; and 5) no previous treatment with radiation (GKS or conventional radiotherapy) for brain metastasis. The authors at one institution have treated two patients, who suffered from severe cancer pain related to bone metastasis, by using GKS. The target was the pituitary gland. The maximum dose was 160 Gy with one isocenter of an 8-mm collimator, keeping the radiation dose to the optic nerve less than 8 Gy. At another institution two patients were treated in the same way; an additional five patients were treated similarly with targeting of the pituitary gland with two isocenters of 4-mm collimator.

In all nine cases, pain resolved without significant complication. Pain relief was observed within several days, and this effect was prolonged until the day that they died. At a follow up of 1 to 24 months, no recurrences and no hormonal dysfunction were observed.

Conclusions. Despite insufficient experience, the efficacy and the safety of GKS for intractable pain were demonstrated in nine patients. This treatment has the potential to ameliorate cancer-related pain, and GKS will play a more important role in the treatment of intractable pain. More experience and additional refined study protocols are needed to evaluate which parameters are important, to determine what treatment strategy is the best, and to clarify the safest option for patients with intractable cancer pain.
Successful treatment of spindle cell sarcoma of the sella turcica
Authors: Alpert Tracy E. , Hahn Seung S. , Chung Chung T. , Bogart Jeffrey A , Hodge Charles J. , Montgomery Craig
Published: November 2018

✓ A primary spindle cell sarcoma of the sella turcica in a patient without a history of radiation treatment is a very rare occurrence. Only one other case has been reported to date, with local recurrence 7 months after the patient underwent subtotal resection and stereotactic radiosurgery of the tumor.

The authors present a case of spindle cell sarcoma of the sella turcica successfully treated by surgery, external-beam radiotherapy, and gamma knife radiosurgery. After 24 months of follow up, the patient continues to show no evidence of disease.
Gamma knife radiosurgery for cavernous hemangiomas in the cavernous sinus
Authors: Nakamura Naoki , Shin Masahiro , Tago Masao , Terahara Atsuro , Kurita Hiroki , Nakagawa Kejichi , Ohtomo Kuni
Published: November 2018

✓ A cavernous hemangioma occurring in the cavernous sinus is a rare vascular tumor that causes cranial nerve symptoms by direct compression. Surgical removal is often difficult because excessive intraoperative bleeding is expected. These lesions remain a therapeutic challenge even with state-of-the-art treatment modalities. The authors report three cases of cavernous hemangioma occurring in the cavernous sinus that were treated with gamma knife radiosurgery, with a mean patient age of 66 years and a mean tumor volume of 2.3 cm3.
Radiosurgery as palliation for brain metastases: a retrospective review of 72 patients harboring multiple lesions at presentation
Authors: Amendola Beatriz E. , Wolf Aizik , Coy Sammie R. , Amendola Marco A.
Published: November 2018

Object. The purpose of this study was to determine the outcome of palliative gamma knife radiosurgery (GKS) in a group of poor-risk patients with multiple brain metastases.

Methods. The medical records of 72 patients with multiple brain metastases treated with GKS between October 1993 and November 9, 2001, were reviewed retrospectively. All patients presented with more than 10 lesions. There were 26 men and 46 women. The median age was 60 years (range 24–84 years). There were 39 patients with lung cancer, 18 with breast cancer, nine with metastatic melanomas, two with metastatic renal cell carcinomas, and four with other primary tumors. A total of 147 treatment sessions were required to treat 1304 sites in 72 patients. A mean of 10.4 isocenters per treatment was used. The mean tumor volume was 1.7 cm3. All patients had extracranial disease. The variables included in this study were the patient's Karnofsky Performance Scale score, age, sex, the radiation dose, initial number of lesions, and tumor volume and histopathology.

Conclusions. Radiosurgery can be a powerful tool in the palliative management of advanced metastatic disease even in patients presenting with multiple brain metastases. A median of two outpatient treatments was required, allowing the advanced cancer patient to avoid protracted fractionated radiotherapy and to undergo other therapeutic treatment with an acceptable quality of life.
Gamma knife radiosurgery for trigeminal neuralgia: the dry-eye complication
Authors: Matsuda Shinji , Serizawa Toru , Sato Makato , Ono Junichi
Published: November 2018

Object. The purpose of this paper is to report a unique complication of gamma knife radiosurgery (GKS) for trigeminal neuralgia (TN). The nature of this complication and its related factors are discussed.

Methods. Forty-one medically refractory patients with TN were treated with GKS. All patients received 80 Gy to the proximal trigeminal nerve root, using a 4-mm collimator and a single isocenter. Follow up consisted of three monthly outpatient sessions after GKS. Improvement, recurrence, complications, and changes in magnetic resonance imaging were recorded. To evaluate the factors behind the complications, a subgroup of 33 patients was assessed in whom the follow-up duration was more than 9 months.

The follow-up duration was 3 to 36 months (mean 13 months). The results were excellent in 20 patients, good in 11, and fair in seven. No patient had a poor result. Three patients suffered recurrences. Seven patients suffered complications 9 to 24 months after GKS. All seven patients complained of facial numbness and hypesthesia was recorded. Three of them also complained of “dry eye” with diminution or absence of corneal reflex but no other abnormalities of the cornea and conjunctiva were found on ophthalmological examination. In these three patients, hypesthesia of the first division of the trigeminal nerve area had been found before their “dry eye” symptoms appeared. The irradiated volume on the brainstem was significantly related to this complication.

Conclusions. The dry eye symptom seems to be a special form of sensory disturbance. An overdose of radiation to the brainstem may play an important role in the manifestation of this complication.
Gamma knife radiosurgery for trigeminal neuralgia associated with multiple sclerosis
Authors: Rogers C. Leland , Shetter Andrew G. , Ponce Francisco A. , Fiedler Jeffrey A. , Smith Kris A. , Speiser Burton L.
Published: November 2018

Object. The authors assessed the efficacy and complications from gamma knife radiosurgery (GKS) for multiple sclerosis (MS)-associated trigeminal neuralgia (TN).

Methods. There were 15 patients with MS-associated TN (MS—TN). Treatment involved three sequential protocols, 70 to 90-Gy maximum dose, using a single 4-mm isocenter targeting the ipsilateral trigeminal nerve at its junction with the pons with the 50% isodose. Pain was appraised by each patient by using Barrow Neurological Institute (BNI) Scores I through IV: I, no pain; II, occasional pain not requiring medication; IIIa, no pain but continued medication; IIIb, some pain, controlled with medication; IV, some pain, not controlled with medication; and V, severe pain/no pain relief.

With a mean follow up of 17 months (range 6–38 months), 12 (80%) of 15 patients experienced pain relief. Three patients (20%) reported no relief (BNI Score V). For responders, the mean latency from treatment to the onset of pain relief was 13 days (range 1–61 days). Maximal relief was achieved after a mean latency of 56 days (range 1–157 days). Five patients underwent a second GKS after a mean interval of 534 days (range 231–946 days). The mean maximum dose at this second treatment was 48 Gy. The target was unchanged from the first treatment. All five patients who underwent repeated GKS improved. Complications were limited to delayed facial hypesthesias. Two (13%) of 15 patients experienced onset of numbness after the first GKS, as well as two of five patients following a second GKS. The patients found this mild and not bothersome. Each patient who developed hypesthesias also experienced complete pain relief.

Conclusions. Gamma knife radiosurgery is an effective treatment for MS—TN. Radiosurgery carries an acceptable small risk of mild facial hypesthesias, and hypesthesia appears predictive of a favorable outcome.
Unusual causes of trigeminal neuralgia treated by gamma knife radiosurgery
Authors: Chang Jin Woo , Choi Jae Young , Yoon Young Sul , Park Yong Gou , Chung Sang Sup
Published: November 2018

✓ The purpose of this paper was to present two cases of secondary trigeminal neuralgia (TN) with an unusual origin and lesion location. In two cases TN was caused by lesions along the course of the trigeminal nerve within the pons and adjacent to the fourth ventricle. Both cases presented with typical TN. Brain magnetic resonance imaging revealed linear or wedge-shaped lesions adjacent to the fourth ventricle, extending anterolaterally and lying along the pathway of the intraaxial trigeminal fibers.

The involvement of the nucleus of the spinal trigeminal tract and of the principal sensory trigeminal nucleus with segmental demyelination are suggested as possible causes for trigeminal pain in these cases. It is postulated that these lesions are the result of an old viral neuritis. The patients underwent gamma knife radiosurgery and their clinical responses have been encouraging to date.
Gamma knife subthalamotomy for Parkinson disease: the subthalamic nucleus as a new radiosurgical target
Authors: Keep Marcus F. , Mastrofrancesco Lois , Erdman Daniel , Murphy Brent , Ashby Lynn S.
Published: November 2018

✓ The authors present the neuroimaging, treatment planning, and radiosurgical technique for the first reported case of unilateral radiosurgical subthalamotomy, which was performed to control motor symptoms associated with advanced Parkinson disease (PD) in a patient who had undergone previous contralateral radiofrequency (RF) pallidotomy.

A 73-year-old woman with end-stage PD had undergone RF pallidotomy of the right globus pallidus with resolution of symptoms. Two years following this procedure, due to the natural progression of her disease, she suffered recurrent motor fluctuations, dyskinesia, and worsening bradykinesia of the right side. Her Parkinson's Disease Disability Rating (PDDR) score was 28. Computerized tomography and magnetic resonance (MR) imaging were used to localize the left subthalamic nucleus (STN). The patient underwent gamma knife radiosurgery—a single shot of 120 Gy was administered using the 4-mm collimator helmet.

The patient was evaluated up to 42 months after the procedure. The dyskinesia became minimal. Right-sided motor control improved as did her balance. At 3 months after treatment MR imaging demonstrated the radiosurgical lesion in the left STN. At 3.5 years postradiosurgery, she experienced minimal focal (oral) dyskinesia, no bradykinesia or rigidity, and her PDDR score was 11.

Radiosurgery of the STN in this case was safe and effective. The STN is a readily localized anatomical target with neuroimaging. Radiosurgery avoids the risks of open procedures.
A planned combined stereotactic approach for cystic intracranial tumors
Authors: Reda Wael Abdel Halim , Hay Alla Abdel , Ganz Jeremy C.
Published: November 2018

✓ Cyst-associated tumors are classified as cysts with neoplastic mural nodules and intratumoral cysts. The solid component of many of these tumors may be appropriate for gamma knife radiosurgery (GKS). At present there is no systematic protocol for GKS treatment of patients harboring tumors with a cystic component. The purpose of this paper is to suggest such a program.

Two cases are presented. One patient had a hemangioblastoma with a cyst and a mural nodule. The second patient had a craniopharyngioma with one large and two small intratumoral cysts. The course in both cases has been satisfactory in the short term. Although the 1-year follow-up period, however, does not provide a basis for determining the correct overall management of such tumors, the treatment strategy does illustrate a program for the management of tumors with associated cysts.

Cysts with tumor nodules in their walls should first be treated with GKS followed by aspiration of the cyst contents, unless special circumstances make this unsuitable. This strategy enables treatment planning to take advantage of the natural barrier a cyst may place between a tumor and important surrounding structures.

Intratumoral cysts may be aspirated and then treated with GKS, with every attempt made to cover the entire target volume including any residual cyst with the prescription dose. This form of treatment requires very careful follow up.

It is probable that in some cases reaccumulation of cyst fluid may require the insertion of an Ommaya reservoir for repeated aspiration or the installation of cytotoxic agents such as bleomycin. This form of treatment is much less traumatic than surgery and does not hinder the performance of subsequent surgery, should this become necessary.
Gamma knife radiosurgery and its possible relationship to malignancy: a review
Authors: Ganz Jeremy C.
Published: November 2018

✓ The question has been raised recently whether gamma knife radiosurgery (GKS) can induce secondary neoplasia. Because there is little or no detailed knowledge about this potential complication, background information culled from the radiotherapy literature is reviewed as a guide to the clinical situations in which radiotherapy may induce secondary neoplastic change. Available case reports are then reviewed and discussed against the background of the current knowledge. On the basis of the review, the following suggestions are proposed on how to limiting the extent of this complication, document its frequency, and inform patients. It should be remembered that: the benefits of GKS are great; its alternatives also have risks; there often are no alternatives to GKS; follow-up documentation should be pursued more actively so that, if possible, no patient falls through the net; practitioners should be proactive in defining the problem, and genetic analysis of tumor biopsy specimens obtained in patients who will undergo or have undergone GKS should become routine; the extent of secondary neoplasia is not known; and patient information should be guided by what is known rather than by what is feared.
Leksell gamma knife lesioning of the rat hippocampus: the relationship between radiation dose and functional and structural damage
Authors: Lis˘c˘ák Roman , Vladyka Vilibald , Novotný Josef , Broz˘ek Gustav , Námĕstková Kater˘ina , Mares˘ Vladislav , Herynek Vít , Jirák Daniel , Hájek Milan , Syková Eva
Published: November 2018

Object. The goals of the study were to determine at what dosage and after what interval impairment of hippocampal function occurs after Leksell gamma knife radiosurgery (GKS) of the rat hippocampus and to assess the associated structural changes.

Methods. Long—Evans rats were irradiated with maximum doses of 25, 50, 75, 100, and 150 Gy, and four 4-mm isocenters were used to cover the hippocampus bilaterally. The impairment of hippocampal function, which is associated with a loss of memory, was measured by testing the impairment of the rats' orientation in a Morris water maze. Changes in the irradiated tissue were measured using magnetic resonance imaging (Bruker 4.7/20 experimental spectrometer). The data were compared with histologically demonstrated changes.

Significantly higher incidences of edema, necrosis, and behavioral changes were observed following administration of doses higher than 50 Gy. No edema, necrosis, or behavioral changes were observed when doses were 25 Gy.

Conclusions. It would seem that rats can be used for experiments involving the induction of complex brain lesions by using four 4-mm isocenters. Testing retention memory for behavioral changes after bilateral GKS of the whole hippocampus proved insensitive; acquisition memory should be tested to assess functional changes of hippocampus. Significantly higher incidences of edema, necrosis, and behavioral changes were observed for doses higher than 50 Gy. There seems to be a therapeutic window during which doses may affect epilepsy without impairing the memory of the rat.
A validation study of a new prognostic index for patients with brain metastases: the Graded Prognostic Assessment
Authors: Sperduto Christina Maria , Watanabe Yoichi , Mullan John , Hood Terry , Dyste Gregg , Watts Charles , Bender Gail Papermaster , Sperduto Paul
Published: November 2018

Object

The purpose of this study was to validate a new prognostic index for patients with brain metastases. This index, the Graded Prognostic Assessment (GPA), is based on an analysis of 1960 patients whose data were extracted from the Radiation Therapy Oncology Group (RTOG) database. The GPA is based on 4 criteria: age, Karnofsky Performance Scale score, number of brain metastases, and the presence/absence of extracranial metastases. Each of the 4 criteria is given a score of 0, 0.5, or 1.0, so the patient with best prognosis would have a GPA score of 4.0.

Methods

Between April 2005 and December 2006, 140 eligible patients with brain metastases were treated at the Gamma Knife Center at the University of Minnesota. The GPA score was calculated for each patient, and the score was then correlated with survival. Survival duration was calculated from the date treatment began for the brain metastases. Eligibility criteria included patients treated with whole-brain radiation therapy, stereotactic radiosurgery, or both.

Results

The median survival time in months observed in the RTOG and Minnesota data by GPA score was as follows: GPA 3.5–4.0, 11.0 and 21.7; GPA 3.0, 8.9 and 17.5; GPA 1.5–2.5, 3.8 and 5.9; and GPA 0–1.0, 2.6 and 3.0, respectively.

Conclusions

The University of Minnesota data correlate well with the RTOG data and validate the use of the GPA as an effective prognostic index for patients with brain metastases. Clearly, not all patients with brain metastases have the same prognosis, and treatment decisions should be individualized accordingly. The GPA score does appear to be as prognostic as the RPA and is less subjective (because the RPA requires assessment of whether the primary disease is controlled), more quantitative, and easier to use and remember. A multiinstitutional validation study of the GPA is ongoing.
Neuroimaging and quality-of-life outcomes in patients with brain metastasis and peritumoral edema who undergo Gamma Knife surgery
Authors: Pan Hung-Chuan , Sun Ming-Hsih , Chen Clayton Chi-Chang , Chen Chun-Jung , Lee Chen-Hui , Sheehan Jason
Published: November 2018

Object

Gamma Knife surgery (GKS) has been shown to be effective for treating many patients with brain metastasis. Some brain metastases demonstrate significant peritumoral edema; radiation may induce cerebral edema or worsening preexisting edema. This study was conducted to evaluate the imaging and neurobehavioral outcomes in patients with preexisting peritumoral edema who then undergo GKS.

Methods

Between August 2003 and January 2008, 63 cases of brain metastasis with significant peritumoral edema (> 20 cm3) were prospectively studied. The study inclusion criteria were as follows: 1) a single metastatic lesion with significant edema (perilesional edema signal volume on FLAIR > 20 cm3); and 2) inclusion of only 1 lesion > 20 cm3 in the study (in cases of multiple lesions noted on FLAIR images). All patients received MR imaging with pulse sequences including T1-weighted imaging and FLAIR with or without contrast and T2-weighted imaging at an interval of 3 months. A neurological assessment and Brain Cancer Module (BCM-20) questionnaire were obtained every 2–3 months. Kaplan–Meier, Cox regression, and logistic regression were used for analysis of survival and associated factors.

Results

At the time of GKS, the median Karnofsky Performance Scale (KPS) score was 70 (range 50–90), and the mean BCM-20 score was 45.5 ± 6.1. The mean tumor volume (± standard deviation) was 5.2 ± 4.6 cm3 with corresponding T2-weighted imaging and FLAIR volumes of 59.25 ± 37.3 and 62.1 ± 38.8 cm3, respectively (R2 = 0.977, p < 0.001). The mean edema index (volume of peritumoral edema/tumor volume) was 17.5 ± 14.5. The mean peripheral and maximum GKS doses were 17.4 ± 2.3 and 35 ± 4.7 Gy, respectively. The median survival was 11 months. The longer survival was related to KPS scores ≥ 70 (p = 0.008), age < 65 years (p = 0.022), and a reduction of > 6 in BCM-20 score (p = 0.007), but survival was not related to preexisting edema or tumor volume. A reduction in BCM-20 score of > 6 was related to decreased volume in T1-weighted and FLAIR imaging (p < 0.001). Thirty-eight (79.2%) of 48 patients demonstrated decreased tumor volume and accompanied by decreased T2-weighted imaging and FLAIR volume. Eight (16.7%) of the 48 patients exhibited increased or stable tumor volume. A margin dose > 18 Gy was more likely to afford tumor reduction and resolution of peritumoral edema (p = 0.005 and p = 0.006, respectively). However, prior external-beam radiation therapy correlated with worsened preexisting peritumoral edema (p = 0.013) and longer maintenance of corticosteroids (p < 0.001).

Conclusions

Patients demonstrating a reduction in the BCM-20 score > 6, age < 65 years, and KPS score ≥ 70 exhibited longer survival. Significant preexisting edema did not influence the tumor response or clinical outcome. The resolution of edema was related to better quality of life but not to longer survival.
A prospective cohort study of microvascular decompression and Gamma Knife surgery in patients with trigeminal neuralgia
Authors: Linskey Mark E. , Ratanatharathorn Vaneerat , Peñagaricano Jose
Published: November 2018

Object

The aim of this study was to analyze 1 surgeon's 4-year experience with microvascular decompression ([MVD], 36 patients) and Gamma Knife surgery ([GKS], 44 patients) in 80 consecutive patients with trigeminal neuralgia (TN).

Methods

The authors conducted a prospective cohort study from March 1999 to December 2003 with an independent clinical assessment of the results and serial patient satisfaction surveys. All patients completed a 2004 patient satisfaction survey (0.5–5 years postoperative), and 70% of surviving patients completed the same survey in 2007 (3.9–8.5 years postoperative). Follow-up was undertaken in 100% of the patients (mean 3.4 ± 2.14 years, range 0.17–8.5 years).

Results

Respective initial and latest follow-up raw pain-free rates were 100 and 80.6% for MVD and 77.3 and 45.5% for GKS. The median time to the maximal benefit after GKS was 4 weeks (range 1 week–6 months). Respective initial, 2-, and 5-year actuarial pain-free rates were 100, 88, and 80% for MVD and 78, 50, and 33% for GKS (p = 0.0002). The relative risk of losing a pain-free status by 5 years posttreatment was 3.35 for patients in the GKS group compared with the MVD group. Initial and 5-year actuarial rates for ≥ 50% pain relief after GKS were 100 and 80%, respectively. The respective rates of permanent mild and severe sensory loss were 5.6 and 0% for patients in the MVD group, as opposed to 6.8 and 2.3% for patients in the GKS group. Anesthesia dolorosa did not occur during the study. Both procedures enjoyed a high degree of early patient satisfaction (95–100%). Microvascular decompression maintained the same rate of patient satisfaction, but satisfaction with GKS decreased to 75% as pain control waned. Twenty-three patients (29%) died of causes unrelated to the TN or the surgical intervention during the follow-up, and their pain status was known at the time of death. Statistically significant intergroup differences for the MVD versus GKS cohorts were age (median 54 years, range 36–70 years vs median 74 years, range 48–92 years, respectively), preoperative symptom duration (median 2.58 years, range 0.33–15 years vs median 7.5, range 0.6–40 years, respectively), and the presence of major comorbidities (2.8 vs 58.3%, respectively).

Conclusions

In this nonrandomized prospective cohort trial of selected patients with potentially relevant intergroup differences, MVD was significantly superior to GKS in achieving and maintaining a pain-free status in those with TN and provided similar early and superior longer-term patient satisfaction rates compared with those for GKS. The complications of wound cerebrospinal fluid leakage, hearing loss, and persistent diplopia (1 case each in the MVD group) were not seen after GKS.
Image registration accuracy of GammaPlan: a phantom study
Authors: Watanabe Yoichi , Han Eunyoung
Published: November 2018

Object

The authors evaluated the accuracy of the automatic image coregistration function implemented in the Leksell GammaPlan treatment planning software (Version 4C with MultiView Extension and Version 8.0).

Methods

The authors used a phantom with 9 landmarks (tips of thin cylindrical acrylic rods) evenly distributed in the treatment space. Two sets of images of the phantom were taken with both CT and MR imaging systems. The first image was obtained with the phantom aligned with the scanner's axis and the second scan was made by intentionally shifting and rotating the phantom relative to the scanner's axis. The authors attempted image registration of 2 CT image sets, CT and MR image sets, and 2 MR image sets. The accuracy of image registration was evaluated by measuring the x, y, and z coordinate values of the landmarks on each image set after 2 image sets were coregistered. The authors calculated the differences of the x, y, and z values and the distance, d, between corresponding landmarks in 2 image sets. To minimize interobserver dependence of coordinate measurements, 2 physicists did measurements independently.

Results

The distances, d, averaged over the 9 landmarks, were 2.63 ± 1.64 and 0.95 ± 0.25 mm for CT–CT and MR–MR image registrations, respectively. When the CT images of the air-filled phantom and MR images were coregistered, however, the algorithm performed poorly: d = 13.8 ± 1.23 mm. To remedy this, the authors undertook a 2-step process by first performing landmark-based registration of the 2 image sets and subsequently applying the automatic registration. With this approach, the mean distance drastically improved: d = 0.74 ± 0.31 mm. When the water-filled phantom was used for CT scans, the registration accuracy of CT and MR image sets was acceptable without the 2-step registration process: d = 1.18 ± 0.36 mm.

Conclusions

The accuracy of automatic registration of image sets from the same modality was within the voxel size of the scanned images. The accuracy of CT–MR image registration strongly depended on whether the phantom for CT scans was filled with air or water. This indicates the significant effect of the amount of common data available for a mutual information-based algorithm on the accuracy.
The Traumatic Coma Data Bank: design, methods, and baseline characteristics
Authors: Foulkes Mary A. , Eisenberg Howard M. , Jane John A. , Marmarou Anthony , Marshall Lawrence F. , _ _
Published: November 2018

✓ The Traumatic Coma Data Bank is a collaborative project to prospectively collect data on the clinical course and outcome of severely head-injured patients. The objectives were to further define the natural history of traumatic head injury, to identify prognostic factors, and to provide planning data for future studies. A brief historical development and a description of the organizational structure and methods are given. The characteristics of the cohort at baseline for the 1030 patients enrolled between January, 1984, and September, 1987, are presented, including a summary of the patients' demographic profile, mechanisms of injury, and intracranial diagnoses. The utility and limitations of these data are discussed.
The outcome of severe closed head injury
Authors: Marshall Lawrence F. , Gautille Theresa , Klauber Melville R. , Eisenberg Howard M. , Jane John A. , Luerssen Thomas G. , Marmarou Anthony , Foulkes Mary A.
Published: November 2018

✓ The outcome of severe head injury was prospectively studied in patients enrolled in the Traumatic Coma Data Bank (TCDB) during the 45-month period from January 1, 1984, through September 30, 1987. Data were collected on 1030 consecutive patients admitted with severe head injury (defined as a Glasgow Coma Scale (GCS) score of 8 or less following nonsurgical resuscitation). Of these, 284 either were brain-dead on admission or had a gunshot wound to the brain. Patients in these two groups were excluded, leaving 746 patients available for this analysis.

The overall mortality rate for the 746 patients was 36%, determined at 6 months postinjury. As expected, the mortality rate progressively decreased from 76% in patients with a postresuscitation GCS score of 3 to approximately 18% for patients with a GCS score of 6, 7, or 8. Among the patients with nonsurgical lesions (overall mortality rate, 31%), the mortality rate was higher in those having an increased likelihood of elevated intracranial pressure as assessed by a new classification of head injury based on the computerized tomography findings. In the 276 patients undergoing craniotomy, the mortality rate was 39%. Half of the patients with acute subdural hematomas died — a substantial improvement over results in previous reports. Outcome differences between the four TCDB centers were small and were, in part, explicable by differences in patient age and the type and severity of injury.

This study describes head injury outcome in four selected head-injury centers. It indicates that a mortality rate of approximately 35% is to be expected in such patients admitted to experienced neurosurgical units.
A simple method for predicting imaging-based complications following gamma knife surgery for cerebral arteriovenous malformations
Authors: Ganz Jeremy C. , Reda Wael A. , Abdelkarim Khalid , Hafez Ayman
Published: November 2018

Object. The authors studied the relationship between dose planning parameters and complications in the treatment of cerebral arteriovenous malformations (AVMs).

Methods. There were 41 continuous unselected patients. The mean follow-up period was 19 months; the mean age was 28 years; the male/female ratio was 2.2:1.0; the median prescription dose was 25 Gy (range 14–25 Gy); the median prescription isodose was 50%. The median lesion volume was 4.4 cm3. The median lesion coverage was 93%; and the mean conformity index was 1.22.

The authors found no relationship between lesion volume or integral dose and the development of the clinical effects based on the adverse radiation effects (AREs); however, there was a significant relationship between both target volume and integral dose with the development of AREs as well as the severity of the AREs.

Conclusions. The integral dose could be used as a guideline for the prescription dose. Arguments are made for maximizing the prescription dose for the long-term safety of the patient.
Gamma knife surgery for cavernous hemangiomas: an analysis of 125 patients
Authors: Liu Kang-Du , Chung Wen-Yuh , Wu Hsiu-Mei , Shiau Cheng-Ying , Wang Ling-Wei , Guo Wan-You , Hung-Chi Pan David
Published: November 2018

Object. The authors sought to determine the value of gamma knife surgery (GKS) in the treatment of cavernous hemangiomas (CHs).

Methods. Between 1993 and 2002, a total of 125 patients with symptomatic CHs were treated with GKS. Ninety-seven patients presented with bleeding and 45 of these had at least two bleeding episodes. Thirteen patients presented with seizures combined with hemorrhage, and 15 patients presented with seizures alone. The mean margin dose of radiation was 12.1 Gy and the mean follow-up time was 5.4 years.

In the 112 patients who had bled the number of rebleeds after GKS was 32. These rebleeds were defined both clinically and based on magnetic resonance imaging for an annual rebleeding rate of 32 episodes/492 patient-years or 6.5%. Twenty-three of the 32 rebleeding episodes occurred within 2 years after GKS. Nine episodes occurred after 2 years; thus, the annual rebleeding rate after GKS was 10.3% for the first 2 years and 3.3% thereafter (p = 0.0038). In the 45 patients with at least two bleeding episodes before GKS, the rebleeding rate dropped from 29.2% (55 episodes/188 patient-years) before treatment to 5% (10 episodes/197 patient-years) after treatment (p < 0.0001). Among the 28 patients who presented with seizures, 15 (53%) had good outcomes (Engel Grades I and II). In this study of 125 patients, symptomatic radiation-induced complications developed in only three patients.

Conclusions. Gamma knife surgery can effectively reduce the rebleeding rate after the first symptomatic hemorrhage in patients with CH. In addition, GKS may be useful in reducing the severity of seizures in patients with CH.
Gamma knife surgery for vestibular schwannoma: 10-year experience of 195 cases
Authors: Chung Wen-Yuh , Liu Kang-Du , Shiau Cheng-Ying , Wu Hsiu-Mei , Wang Ling-Wei , Guo Wan-Yuo , Ming-Tak Ho Donald , Hung-Chi Pan David
Published: November 2018

Object. The authors conducted a study to determine the optimal radiation dose for vestibular schwannoma (VS) and to examine the histopathology in cases of treatment failure for better understanding of the effects of irradiation.

Methods. A retrospective study was performed of 195 patients with VS; there were 113 female and 82 male patients whose mean age was 51 years (range 11–82 years). Seventy-two patients (37%) had undergone partial or total excision of their tumor prior to gamma knife surgery (GKS). The mean tumor volume was 4.1 cm3 (range 0.04–23.1 cm3). Multiisocenter dose planning placed a prescription dose of 11 to 18.2 Gy on the 50 to 94% isodose located at the tumor margin. Clinical and magnetic resonance (MR) imaging follow-up evaluations were performed every 6 months.

A loss of central enhancement was demonstrated on MR imaging in 69.5% of the patients. At the latest MR imaging assessment decreased or stable tumor volume was demonstrated in 93.6% of the patients. During a median follow-up period of 31 months resection was avoided in 96.8% of cases. Uncontrolled tumor swelling was noted in five patients at 3.5, 17, 24, 33, and 62 months after GKS, respectively. Twelve of 20 patients retained serviceable hearing. Two patients experienced a temporary facial palsy. Two patients developed a new trigeminal neuralgia. There was no treatment-related death. Histopathological examination of specimens in three cases (one at 62 months after GKS) revealed a long-lasting radiation effect on vessels inside the tumor.

Conclusions. Radiosurgery had a long-term radiation effect on VSs for up to 5 years. A margin 12-Gy dose with homogeneous distribution is effective in preventing tumor progression, while posing no serious threat to normal cranial nerve function.
Gamma knife surgery for multiple hemangioblastomas
Authors: Park Yong Sook , Chang Jong Hee , Chang Jin Woo , Chung Sang Sup , Park Yong Gou
Published: November 2018

Object. The authors describe their experience in treating patients with hemangioblastoma, especially multiple lesions, with gamma knife surgery (GKS).

Methods.Nine patients with 84 hemangioblastomas underwent GKS between July 1992 and May 2003. Three patients harbored a single lesion and six patients had multiple lesions. Of the six patients with multifocal tumors, a diagnosis of von Hippel—Lindau disease had been established in five. In the patients with multiple lesions, the mean radiation dose delivered to the tumor margin was 16.6 Gy (range 12.8–29.75 Gy). The mean margin isodose was 60% (range 40–95%).

Three of the 84 lesions failed to be controlled after a mean follow-up period of 4.3 years (range 8.6–141 months). One patient who had undergone two GKS treatments suffered delayed radiation-induced complications, and posterior fossa decompression and ventriculoperitoneal shunt insertion were required.

Conclusions. To achieve tumor control and avoid morbidity, the surgeon should keep in mind minimizing field overlapping by using a small-diameter collimator or applying a steep dose gradient, and by accurate dose prescription.
Gamma knife surgery for intracranial cavernous hemangioma
Authors: Kim Moo Seong , Pyo Se Young , Jeong Young Gyun , Lee Sun Il , Jung Yong Tae , Sim Jae Hong
Published: November 2018

Object. The purpose of this study was to assess the benefits of radiosurgery for cavernous hemangioma.

Methods. Sixty-five cavernous hemangiomas were treated with gamma knife surgery (GKS) between October 1994 and December 2002. Forty-two patients attended follow up. The mean patient age was 37.6 years (range 7–60 years). The lesions were located in the frontal lobe in 12 cases, deep in the parietal lobe in five, in the basal ganglia in five, in the temporal in three, in the cerebellum in three, in the pons/midbrain in six, and in multiple locations in eight cases. The presenting symptoms were seizure in 12, hemorrhage in 11, and other in 19. The maximum dose was 26.78 Gy, and the mean margin dose was 14.55 Gy.

The mean follow-up period after radiosurgery was 29.6 months (range 5–93 months). The tumor decreased in size in 29 cases, was unchanged in 12, and increased in size in one. In the seizure group, seizures were controlled without anticonvulsant medication in nine cases (81.8%) after 31.3 months (range 12–80 months). After 93 months, one patient developed a cyst, which was resected. Rebleeding occurred in one case (2.3%). On T2-weighted imaging changes were seen in 11 cases (26.2%), in three (7.1%) of which neurological deterioration was correlated with imaging changes. In other cases these deficits were temporary.

Conclusions. The authors found that GKS was an effective treatment modality for cavernous hemangiomas, especially for those located within the brainstem, basal ganglia, or deep portions of the brain. It can reduce seizure frequency significantly although this takes time. In the group receiving a marginal dose below 15 Gy the patients fared better than when the dose exceeded 15 Gy.
Visual changes after gamma knife surgery for optic nerve tumors
Authors: Kwon Yang , Bae Jun Seok , Kim Jae Myung , Lee Do Hee , Kim Soon Young , Ahn Jae Sung , Kim Jeong Hoon , Kim Chang Jin , Kwun Byung Duk , Lee Jung Kyo
Published: November 2018

✓ Tumors involving the optic nerve (optic glioma, optic nerve sheath meningioma) are benign but difficult to treat. Gamma knife surgery (GKS) may be a useful treatment. The authors present data obtained in three such cases and record the effects of GKS.
Gamma knife surgery for hemangioblastomas
Authors: Tago Masao , Terahara Atsuro , Shin Masahiro , Maruyama Keisuke , Kurita Hiroki , Nakagawa Keiichi , Ohtomo Kuni
Published: November 2018

Object. The authors reviewed their 14-year experience using stereotactic radiosurgery for the treatment of hemangioblastomas and define the role and the proper strategy for radiosurgery of this condition.

Methods. This is a retrospective study of 38 hemangioblastomas in 13 patients. Seven patients had von Hippel—Lindau disease. All patients have undergone at least one follow-up visit. The median and mean tumor volumes were 0.23 cm3 and 0.72 cm3 respectively (range 0.004:4.84 cm3). Twenty-eight tumors received 20 Gy to the margin, and the remainder received 18 Gy. The median clinical follow-up period was 36 months (range 3–159 months).

No patient died. The survival rate was 84.6% (11 of 13 patients). The actuarial 5- and 10-year survival rates were both 80.8%. The median radiological follow-up period was 35 months (range 7–147 months). Only one tumor increased in volume 24 months after treatment in association with an intratumoral hemorrhage. The tumor control rate was 97.4% (37 of 38 tumors). Actuarial 5- and 10-year control rates were both 96.2%. New lesions and/or those increasing in size outside the irradiated area were discovered in five patients (38.5%). Nine tumors revealed peritumoral contrast enhancement which was seen more frequently in larger tumors with a volume greater than 0.5 cm3 (p = 0.0034).

Conclusions. Gamma knife surgery is a safe and effective method to control hemangioblastomas for as many as 10 years. Higher doses and smaller tumors probably contribute to good outcomes. Recurrence outside the original irradiated area is common. Peritumoral contrast enhancement may be seen in larger tumors. The authors recommend regular imaging follow up and early repeated treatment in the face of new or growing tumors.
Pineal tumors: analysis of treatment results in 20 patients
Authors: Amendola Beatriz E. , Wolf Aizik , Coy Sammie R. , Amendola Marco A. , Eber Daryl
Published: November 2018

Object. The authors evaluate their results when using gamma knife surgery (GKS) in the management of patients with tumors in the pineal region.

Methods. This is a retrospective clinical evaluation of 20 patients with primary tumors of the pineal region treated with GKS from November 1994 through August 2003. There were 13 germ cell tumors, two pineoblastomas, two low-grade gliomas, one primitive neuroectodermal tumor, one teratoma, and one pineocytoma. There were 10 male and 10 female patients. Their median age was 15.5 years (range 5–71 years). The median margin dose was 11 Gy (range 8–20 Gy). The median target volume was 3.1 cm3 (range 0.1–49.9 cm3). Five patients received sequential systemic chemotherapy and four underwent adjuvant conventional radiation therapy. Seventeen (85%) of 20 patients are alive with a median survival of 30.4 months (range 0–-85.7 months). Two patients required retreatment. Three patients died: one of unrelated causes, one who presented with extensive local disease, and the other of meningeal carcinomatosis with local control of the primary tumor. No complications from GKS were noted.

Conclusions. This initial experience suggests that GKS is a valuable treatment modality for the management of pineal region tumors. This technique offers excellent local tumor control and minimal patient morbidity, allowing for immediate use of systemic chemotherapy and/or conventional radiation if indicated.
Increased preservation of functional hearing after gamma knife surgery for vestibular schwannoma
Authors: van Eck Albertus T. C. J. , Horstmann Gerhard A.
Published: November 2018

Object. Gamma knife surgery (GKS) for vestibular schwannoma is still associated with an additional hearing loss of approximately 30%. The purpose of this study was to record the effect on hearing preservation of maintaining a margin dose of 13 Gy while reducing the maximum dose to 20 Gy.

Methods. Seventy-eight of 95 patients who entered a prospective protocol with a follow up of at least 12 months (mean 22 months) were evaluated. The mean tumor volume was 2.28 cm3. After a mean follow-up duration of 22 months, the magnetic resonance imaging—based tumor control rate was 87%. In two cases a second procedure (surgery) was necessary. Thus, the clinical control rate was 97.5%. In two cases there was an increase in trigeminal dysesthesia. One patient suffered transient facial nerve impairment. Functional hearing was preserved in 83.4% of the patients with functional hearing preoperatively.

Conclusions. Reducing the maximum dose to 20 Gy seems to be an effective treatment, which probably increases preservation of functional hearing without sacrificing the high tumor control rates achieved in radiosurgery. Post-radiosurgery tumor swelling occurred in 25% of the cases and was not correlated with hearing deterioration.
Gamma knife surgery of superficially located meningioma
Authors: Kim Dong Gyu , Kim Chi Heon , Chung Hyun-Tai , Paek Sun Ha , Jeong Sang Soon , Han Dae Hee , Jung Hee-Won
Published: November 2018

Object. The authors analyzed tumor control rates and complications in patients with superficially located meningiomas after gamma knife surgery (GKS).

Methods. Between 1998 and 2003, GKS was performed in 23 patients with 26 lesions in whom follow-up imaging for 1 year or more was available. The male/female ratio was 1:22. The mean age was 59 years. The median tumor volume was 4.7 cm3, and the mean margin dose was 16 Gy at the 50% isodose line. Peritumoral edema was revealed on magnetic resonance (MR) imaging in four patients before GKS. Magnetic resonance imaging and clinical examinations were performed every 6 months after GKS. The mean follow-up duration was 32 months.

The tumor shrank in eight cases, was stable in 17, and enlarged in one; thus 25 (95%) of 26 tumors were controlled. A peritumoral high signal on T2-weighted MR images was found in eight lesions and preexisting edema was aggravated in three lesions after GKS. Ten of these 11 patients complained of severe headache, and three patients experienced neurological deficits at the same time after a mean latency of 3 months; however, high signal was not demonstrated on imaging before 6 months on average. Steroid agents, when required, gave relief to all patients. The complication rate was 43% (10 of 23 cases). High signal disappeared in nine patients and decreased in the remaining two. High signal was associated with a high integral dose and a large tumor volume. Tumor shrinkage at the last follow-up examination was more prominent in the patients with symptomatic high signal (p = 0.03).

Conclusions. There was a good tumor control rate with a high complication rate. Longer follow up of more patients is needed. Adjusting the dose—volume relationship should be considered to reduce complications.
Microvascular decompression after gamma knife surgery for trigeminal neuralgia: intraoperative findings and treatment outcomes
Authors: Shetter Andrew G. , Zabramski Joseph M. , Speiser Burton L.
Published: November 2018

Object. The authors sought to determine whether the results of trigeminal microvascular decompression (MVD) are influenced by prior gamma knife surgery (GKS).

Methods. Gamma knife surgery is an established procedure for treating medically intractable trigeminal neuralgia but failures do occur. The authors assessed six patients (two men and four women; mean age 52 years) who experienced pain recurrence after GKS and elected to undergo trigeminal MVD via retrosigmoid craniotomy. Three patients underwent a single GKS to a maximal dose of 80 Gy, whereas three others underwent a second GKS to total of 120 to 135 Gy.

At surgery, none of the six patients demonstrated excess arachnoid thickening, grossly apparent changes in the nerve itself, or any other tissue alterations that made successful mobilization of a blood vessel from the trigeminal root entry zone technically more difficult. A single individual had a small atherosclerotic plaque in the superior cerebellar artery near its contact point with the trigeminal nerve. Follow up at a mean of 25.4 months (range 7.5–42 months) indicated that five patients were pain free. One patient had improved but still relied on medications for pain control.

Conclusions. In the authors' experience, trigeminal MVD can be performed without added difficulty in patients who have previously undergone GKS. The success rates seem similar to those normally associated with MVD. Patients who elect the less invasive option of GKS can be assured that trigeminal MVD remains a viable alternative at a later date if further surgery is required.