Skull base approaches and gamma knife radiosurgery for multimodality treatment of skull base tumors

2002 ◽  
Vol 97 ◽  
pp. 674-676 ◽  
Author(s):  
Paul C. Francel ◽  
Sumon Bhattacharjee ◽  
Paul Tompkins
Keyword(s):  
Radiation Dose ◽  
Skull Base ◽  
Gamma Knife ◽  
Gamma Knife Radiosurgery ◽  
Multimodality Treatment ◽  
Skull Base Tumor ◽  
Skull Base Tumors ◽  
Content Type ◽  
Fine Print

Object. The purpose of this study was to evaluate descriptive data obtained in patients who had received multimodality treatment with resection and gamma knife radiosurgery (GKS) for skull base tumors. Retrospective data were collected from 71 patients with skull base tumors who were treated from November 1996 to December 2000, all of whom underwent follow-up evaluation at 1 year or more. Methods. Data were collected from hospital charts and office records, including patient age, tumor type and location, number of tumors, maximum radiation dose, estimated radiation dose to the periphery, tumor volume, and percentage of patients with tumors smaller or the same size at follow-up evaluation. Conclusions. Of the 71 patients with 1 year or more of follow up, 93% had tumor either the same size or smaller and 34% of these patients had a smaller tumor size. It is concluded that: 1) GKS with multimodality treatment is effective for control of skull base tumors; 2) the radiosurgical team should consider the benefits of GKS for treatment of any skull base tumor to afford optimum patient management; and 3) neurosurgeons involved with the management of skull base tumors should either be trained and proficient in GKS or work closely with a colleague trained in the technique. This will ensure proper consideration of both options, resulting in overall improved patient treatment.

Analysis of the causes of treatment failure in gamma knife radiosurgery for intracranial arteriovenous malformations

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 104-106 ◽  
Author(s):  
Yang Kwon ◽  
Sang Ryong Jeon ◽  
Jeong Hoon Kim ◽  
Jung Kyo Lee ◽  
Dong Sook Ra ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Treatment Failure ◽  
Gamma Knife ◽  
Arteriovenous Malformations ◽  
Gamma Knife Radiosurgery ◽  
Intracranial Arteriovenous Malformations ◽  
Content Type ◽  
The Mean ◽  
Fine Print

Object. The authors sought to analyze causes for treatment failure following gamma knife radiosurgery (GKS) for intracranial arteriovenous malformations (AVMs), in cases in which the nidus could still be observed on angiography 3 years postsurgery. Methods. Four hundred fifteen patients with AVMs were treated with GKS between April 1990 and March 2000. The mean margin dose was 23.6 Gy (range 10–25 Gy), and the mean nidus volume was 5.3 cm3 (range 0.4–41.7 cm3). The KULA treatment planning system and conventional subtraction angiography were used in treatment planning. One hundred twenty-three of these 415 patients underwent follow-up angiography after GKS. After 3 years the nidus was totally obliterated in 98 patients (80%) and partial obliteration was noted in the remaining 25. There were several reasons why complete obliteration was not achieved in all cases: inadequate nidus definition in four patients, changes in the size and location of the nidus in five patients due to recanalization after embolization or reexpansion after hematoma reabsorption, a large AVM volume in five patients, a suboptimal radiation dose to the thalamic and basal ganglia in eight patients, and radioresistance in three patients with an intranidal fistula. Conclusions. The causes of failed GKS for treatment of AVMs seen on 3-year follow-up angiograms include inadequate nidus definition, large nidus volume, suboptimal radiation dose, recanalization/reexpansion, and radioresistance associated with an intranidal fistula.

Risk of injury to cranial nerves after gamma knife radiosurgery for skull base meningiomas: experience in 88 patients

1999 ◽  
Vol 90 (1) ◽  
pp. 42-49 ◽  
Author(s):  
Akio Morita ◽  
Robert J. Coffey ◽  
Robert L. Foote ◽  
David Schiff ◽  
Deborah Gorman
Keyword(s):  
Skull Base ◽  
Gamma Knife ◽  
Cranial Nerves ◽  
Gamma Knife Radiosurgery ◽  
Median Dose ◽  
Trigeminal Neuropathy ◽  
Content Type ◽  
Skull Base Meningiomas ◽  
Fine Print

Object. In this study the authors sought to determine the neurological risks and potential clinical benefits of gamma knife radiosurgery for skull base meningiomas.Methods. A consecutive series of 88 patients harboring skull base meningiomas were treated between 1990 and 1996 by using the Leksell gamma knife in a prospective clinical study that included a strict dose—volume protocol. Forty-nine patients had previously undergone surgery, and six had received external-beam radiotherapy. The median treatment volume was 10 cm3, and the median dose to the tumor margin was 16 Gy. The radiosurgical dosage to the optic nerve, the cavernous sinus, and Meckel's cave was calculated and correlated with clinical outcome. The median patient follow-up time was 35 months (range 12–83 months).Two tumors (2.3%) progressed after radiosurgery; the progression-free 5-year survival rate was 95%. At last follow-up review, 60 (68%) tumors were smaller and 26 (29.5%) remained unchanged. Clinical improvement (in vision, trigeminal pain, or other cranial nerve symptoms) occurred in 15 patients. Functioning optic nerves received a median dose of 10 Gy (range 1–16 Gy), and no treatment-induced visual loss occurred. Among nine patients with new trigeminal neuropathy, six received doses of more than 19 Gy to Meckel's cave.Conclusions. Gamma knife radiosurgery appeared to be an effective method to control the growth of most skull base meningiomas in this intermediate-term study. The risk of trigeminal neuropathy seemed to be associated with doses of more than 19 Gy, and the optic apparatus appeared to tolerate doses greater than 10 Gy. Considering the risks to cranial nerves associated with open surgery for comparable tumors, the authors believe that gamma knife radiosurgery is a useful method for the management of properly selected recurrent, residual, or newly diagnosed skull base meningiomas.

Gamma knife radiosurgery as a single treatment modality for large cerebral arteriovenous malformations

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 113-119 ◽  
Author(s):  
D. Hung-Chi Pan ◽  
Wan-Yuo Guo ◽  
Wen-Yuh Chung ◽  
Cheng-Ying Shiau ◽  
Yue-Cune Chang ◽  
...  
Keyword(s):  
Gamma Knife ◽  
Arteriovenous Malformations ◽  
Radiation Treatment ◽  
Gamma Knife Radiosurgery ◽  
Consecutive Series ◽  
Content Type ◽  
Obliteration Rate ◽  
Complete Obliteration ◽  
Fine Print

Object. A consecutive series of 240 patients with arteriovenous malformations (AVMs) treated by gamma knife radiosurgery (GKS) between March 1993 and March 1999 was evaluated to assess the efficacy and safety of radiosurgery for cerebral AVMs larger than 10 cm3 in volume. Methods. Seventy-six patients (32%) had AVM nidus volumes of more than 10 cm3. During radiosurgery, targeting and delineation of AVM nidi were based on integrated stereotactic magnetic resonance (MR) imaging and x-ray angiography. The radiation treatment was performed using multiple small isocenters to improve conformity of the treatment volume. The mean dose inside the nidus was kept between 20 Gy and 24 Gy. The margin dose ranged between 15 to 18 Gy placed at the 55 to 60% isodose centers. Follow up ranged from 12 to 73 months. There was complete obliteration in 24 patients with an AVM volume of more than 10 cm3 and in 91 patients with an AVM volume of less than 10 cm3. The latency for complete obliteration in larger-volume AVMs was significantly longer. In Kaplan—Meier analysis, the complete obliteration rate in 40 months was 77% in AVMs with volumes between 10 to 15 cm3, as compared with 25% for AVMs with a volume of more than 15 cm3. In the latter, the obliteration rate had increased to 58% at 50 months. The follow-up MR images revealed that large-volume AVMs had higher incidences of postradiosurgical edema, petechiae, and hemorrhage. The bleeding rate before cure was 9.2% (seven of 76) for AVMs with a volume exceeding 10 cm3, and 1.8% (three of 164) for AVMs with a volume less than 10 cm3. Although focal edema was more frequently found in large AVMs, most of the cases were reversible. Permanent neurological complications were found in 3.9% (three of 76) of the patients with an AVM volume of more than 10 cm3, 3.8% (three of 80) of those with AVM volume of 3 to 10 cm3, and 2.4% (two of 84) of those with an AVM volume less than 3 cm3. These differences in complications rate were not significant. Conclusions. Recent improvement of radiosurgery in conjunction with stereotactic MR targeting and multiplanar dose planning has permitted the treatment of larger AVMs. It is suggested that gamma knife radiosurgery is effective for treating AVMs as large as 30 cm3 in volume with an acceptable risk.

Factors related to complete occlusion of arteriovenous malformations after gamma knife radiosurgery

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 96-101 ◽  
Author(s):  
Jong Hee Chang ◽  
Jin Woo Chang ◽  
Yong Gou Park ◽  
Sang Sup Chung
Keyword(s):  
Gamma Knife ◽  
Arteriovenous Malformations ◽  
Gamma Knife Radiosurgery ◽  
Maximum Diameter ◽  
Content Type ◽  
Complete Occlusion ◽  
Factors Associated ◽  
Martin Grade ◽  
Fine Print

Object. The authors sought to evaluate the effects of gamma knife radiosurgery (GKS) on cerebral arteriovenous malformations (AVMs) and the factors associated with complete occlusion. Methods. A total of 301 radiosurgical procedures for 277 cerebral AVMs were performed between December 1988 and December 1999. Two hundred seventy-eight lesions in 254 patients who were treated with GKS from May 1992 to December 1999 were analyzed. Several clinical and radiological parameters were evaluated. Conclusions. The total obliteration rate for the cases with an adequate radiological follow up of more than 2 years was 78.9%. In multivariate analysis, maximum diameter, angiographically delineated shape of the AVM nidus, and the number of draining veins significantly influenced the result of radiosurgery. In addition, margin radiation dose, Spetzler—Martin grade, and the flow pattern of the AVM nidus also had some influence on the outcome. In addition to the size, topography, and radiosurgical parameters of AVMs, it would seem to be necessary to consider the angioarchitectural and hemodynamic aspects to select proper candidates for radiosurgery.

Gamma knife radiosurgery as a lesioning technique in movement disorder surgery

1998 ◽  
Vol 89 (2) ◽  
pp. 183-193 ◽  
Author(s):  
Ronald F. Young ◽  
Anne Shumway-Cook ◽  
Sandra S. Vermeulen ◽  
Peter Grimm ◽  
John Blasko ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Movement Disorder ◽  
Gamma Knife ◽  
Movement Disorders ◽  
Gamma Knife Radiosurgery ◽  
Safety And Efficacy ◽  
Content Type ◽  
Fine Print

Object. To increase knowledge of the safety and efficacy of the use of gamma knife radiosurgery in patients with movement disorders, the authors describe their own experience in this field and include blinded independent assessments of their results. Methods. Fifty-five patients underwent radiosurgical placement of lesions either in the thalamus (27 patients) or globus pallidus (28 patients) for treatment of movement disorders. Patients were evaluated pre- and postoperatively by a team of observers skilled in the assessment of gait and movement disorders who were blinded to the procedure performed. The observers were not associated with the surgical team and concomitantly and blindly also assessed a group of 11 control patients with Parkinson's disease who did not undergo any surgical procedures. All stereotactic lesions were made with the Leksell gamma unit using the 4-mm secondary collimator helmet and a single isocenter with maximum doses from 120 to 160 Gy. Clinical follow-up evaluation indicated that 88% of patients who underwent thalamotomy became tremor free or nearly tremor free. Statistically significant improvements in performance were noted in the independent assessments of Unified Parkinson's Disease Rating Scale (UPDRS) scores in the patients undergoing thalamotomy. Of patients undergoing pallidotomy who had exhibited levodopainduced dyskinesias, 85.7% had total or near-total relief of that symptom. Clinical assessment indicated improvements in bradykinesia and rigidity in 64.3% of patients who underwent pallidotomy. Independent blinded assessments did not reveal statistically significant improvements in Hoehn and Yahr scores or UPDRS scores. On the other hand, 64.7% of patients showed improvements in subscores of the UPDRS, including activities of daily living (58%), total contralateral score (58%), and contralateral motor scores (47%). Total ipsilateral score and ipsilateral motor scores were both improved in 59% of patients. One (1.8%) of 55 patients experienced a homonymous hemianopsia 9 months after pallidotomy due to an unexpectedly large lesion. No other complications of any kind were seen. Neuropsychological test scores that were obtained for the combined pallidotomy and thalamotomy treatment groups preoperatively and at 6 months postoperatively demonstrated an absence of cognitive morbidity. Follow-up neuroimaging confirmed correct lesion location in all patients, with a mean maximum deviation from the planned target of 1 mm in the vertical axis. Measurements of lesions at regular intervals on postoperative magnetic resonance images demonstrated considerable variability in lesion volumes. The safety and efficacy of functional lesions made with the gamma knife appear to be similar to those made with the assistance of electrophysiological guidance with open functional stereotactic procedures. Conclusions. Functional lesions may be made safely and accurately using gamma knife radiosurgical techniques. The efficacy is equivalent to that reported for open techniques that use radiofrequency lesioning methods with electrophysiological guidance. Complications are very infrequent with the radiosurgical method. The use of functional radiosurgical lesioning to treat movement disorders is particularly attractive in older patients and in those with major systemic diseases or coagulopathies; its use in the general movement disorder population seems reasonable as well.

Radiosurgery for Cushing's disease after failed transsphenoidal surgery

2000 ◽  
Vol 93 (5) ◽  
pp. 738-742 ◽  
Author(s):  
Jonas M. Sheehan ◽  
Mary L. Vance ◽  
Jason P. Sheehan ◽  
Dilantha B. Ellegala ◽  
Edward R. Laws
Keyword(s):  
Gamma Knife ◽  
Cushing’S Disease ◽  
Tumor Size ◽  
Transsphenoidal Surgery ◽  
Gamma Knife Radiosurgery ◽  
Magnetic Resonance Images ◽  
Cushing's Disease ◽  
Content Type ◽  
Fine Print

Object. Although transsphenoidal surgery has become the standard of care for Cushing's disease, it is often unsuccessful in normalizing cortisol production. In this study the authors investigate the safety and efficacy of gamma knife radiosurgery (GKRS) for Cushing's disease after failed transsphenoidal surgery.Methods. The records of all patients who underwent GKRS at the authors' institution after unsuccessful transsphenoidal surgery for Cushing's disease were retrospectively reviewed. Successful treatment was considered a normal or below-normal 24-hour urinary free cortisol (UFC) level. Records were also evaluated for relapse, new-onset endocrine deficiencies, interval change in tumor size, and visual complications.Forty-three patients underwent 44 gamma knife procedures with follow up ranging from 18 to 113 months (mean 39.1, median 44 months). Normal 24-hour UFC levels were achieved in 27 patients (63%) at an average time from treatment of 12.1 months (range 3–48 months). Three patients had a recurrence of Cushing's disease at 19, 37, and 38 months, respectively, after radiosurgery. New endocrine deficiencies were noted in seven patients (16%). Follow-up magnetic resonance images obtained in 33 patients revealed a decrease in tumor size in 24, no change in nine, and an increase in size in none of the patients. One patient developed a quadrantanopsia 14 months after radiosurgery despite having received a dose of only 0.7 Gy to the optic tract.Conclusions. Gamma knife radiosurgery appears to be safe and effective for the treatment of Cushing's disease refractory to pituitary surgery. Delayed recurrences and new hormone deficiencies may occur, indicating the necessity for regular long-term follow up.

Linear accelerator radiosurgery for vestibular schwannoma

2001 ◽  
Vol 94 (1) ◽  
pp. 7-13 ◽  
Author(s):  
Roberto Spiegelmann ◽  
Zvi Lidar ◽  
Jana Gofman ◽  
Dror Alezra ◽  
Moshe Hadani ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Gamma Knife ◽  
Linear Accelerator ◽  
Imaging Modality ◽  
Gamma Knife Radiosurgery ◽  
Cranial Neuropathy ◽  
Content Type ◽  
Linac Radiosurgery ◽  
Acoustic Neuromas ◽  
Fine Print

Object. The use of radiosurgery in the treatment of acoustic neuromas has increased substantially during the last decade. Most published experience relates to the use of the gamma knife. In this report, the authors review the methods and results of linear accelerator (LINAC) radiosurgery in 44 patients with acoustic neuromas who were treated between 1993 and 1997. Methods. Computerized tomography scanning was selected as the stereotactic imaging modality for target definition. A single, conformally shaped isocenter was used in the treatment of 40 patients; two or three isocenters were used in four patients who harbored very irregular tumors. The radiation dose directed to the tumor border was the only parameter that changed during the study period: in the first 24 patients who were treated the dose was 15 to 20 Gy, whereas in the last 20 patients the dose was reduced to 11 to 14 Gy. After a mean follow-up period of 32 months (range 12–60 months), 98% of the tumors were controlled. The actuarial hearing preservation rate was 71%. New transient facial neuropathy developed in 24% of the patients and persisted to a mild degree in 8%. Radiation dose correlated significantly with the incidence of cranial neuropathy, particularly in large tumors (≥ 4 cm3). Conclusions. Single-isocenter LINAC radiosurgery proved to be an effective treatment for acoustic neuromas in this series, with results that were comparable with those reported for gamma knife radiosurgery and multiple isocenters.

Acute symptoms after gamma knife radiosurgery

2002 ◽  
Vol 97 ◽  
pp. 631-634 ◽  
Author(s):  
E. J. St. George ◽  
J. Kudhail ◽  
J. Perks ◽  
P. N. Plowman
Keyword(s):  
Adverse Events ◽  
Gamma Knife ◽  
Gamma Knife Radiosurgery ◽  
Neurological Dysfunction ◽  
Content Type ◽  
Lesion Type ◽  
Patient Groups ◽  
Pin Site ◽  
Fine Print

Object. The purpose of this study was to examine the widely held assumption that early-onset symptoms after gamma knife radiosurgery (GKS) are uncommon. The study was designed to include all types of morbidity and not just those that lead to neurological dysfunction. It was hoped that the results of the study could lead to a more rational follow-up protocol. Methods. Data regarding adverse events were collected prospectively (within 2–3 weeks post-GKS) by telephone interview from 47 of the first 65 patients who could be reached. Immediate adverse events were defined as any new or unexpected symptom developing within 2 weeks of treatment and were graded as mild, moderate, or severe. Two thirds of all patients complained of new adverse symptoms; three patients required prolonged hospitalization, although in one case this was not related to the radiosurgery. The majority of symptomatic patients (91%) experienced mild or moderate complications. More than 50% of patients had headache. One third described pin site—related complications and one fifth suffered from nausea/vomiting or marked tiredness. Patients with moderate symptoms had a larger mean tumor volume and higher radiation dose than other patient groups. Prior radiation therapy, lesion type, or the posttreatment administration of steroid agents did not significantly influence the development of acute symptoms. Conclusions. Acute adverse events following GKS are not uncommon if all types of morbidity are considered. An increased appreciation of these other complications may improve posttreatment care.

Gamma knife radiosurgery for trigeminal neuralgia: the dry-eye complication

2002 ◽  
Vol 97 ◽  
pp. 525-528 ◽  
Author(s):  
Shinji Matsuda ◽  
Toru Serizawa ◽  
Makato Sato ◽  
Junichi Ono
Keyword(s):  
Trigeminal Neuralgia ◽  
Gamma Knife ◽  
Dry Eye ◽  
Trigeminal Nerve ◽  
Gamma Knife Radiosurgery ◽  
Ophthalmological Examination ◽  
Related Factors ◽  
Content Type ◽  
Fine Print

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 using 90 Gy for trigeminal neuralgia

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 152-154 ◽  
Author(s):  
Bradley Nicol ◽  
William F. Regine ◽  
Claire Courtney ◽  
Ali Meigooni ◽  
Michael Sanders ◽  
...  
Keyword(s):  
Trigeminal Neuralgia ◽  
Gamma Knife ◽  
Gamma Knife Radiosurgery ◽  
Complete Relief ◽  
Entry Zone ◽  
Content Type ◽  
Root Entry Zone ◽  
Good Pain Control ◽  
Fine Print

Object. The purpose of this paper was to assess the treatment of trigeminal neuralgia (TN) with the higher than normal dose of 90 Gy. Methods. Forty-two patients with typical TN were treated over a 3-year period with gamma knife radiosurgery. Every patient received a maximum dose of 90 Gy in a single 4-mm isocenter targeted to the root entry zone of the trigeminal nerve. Thirty of 42 patients had undergone no prior treatments. The median follow-up period was 14 months (range 2–30 months). Thirty-one patients (73.8%) achieved complete relief of pain. Nine patients (21.4%) obtained good pain control. Complications were limited to increased facial paresthesia in seven patients (16.7%) and dysgeusia in four patients (9.5%). Conclusions. The authors conclude that the use of 90 Gy is a safe and effective dose for the treatment of TN.

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