Gamma Knife surgery for schwannomas originating from cranial nerves III, IV, and VI

2008 ◽  
Vol 109 (Supplement) ◽  
pp. 149-153 ◽  
Author(s):  
In-Young Kim ◽  
Douglas Kondziolka ◽  
Ajay Niranjan ◽  
John C. Flickinger ◽  
L. Dade Lunsford
Keyword(s):  
Gamma Knife ◽  
Tumor Regression ◽  
Cranial Nerves ◽  
Neurofibromatosis Type ◽  
Symptomatic Improvement ◽  
Gamma Knife Surgery ◽  
Invasive Approach ◽  
Presenting Symptoms ◽  
History Of

Object Schwannomas from the motor cranial nerves controlling eye movement are rare. The authors evaluated the role of Gamma Knife surgery (GKS) in the management of schwannomas originating from cranial nerves III, IV, and VI. Methods Over a 7-year period, 8 patients with schwannomas originating from the oculomotor (2 patients), trochlear (5 patients), or abducent (1) nerve underwent GKS. The mean patient age was 46.1 years (range 19–59 years). The presenting symptoms included diplopia in 5 patients, ptosis in 1 patient, ophthalmoplegia in 1 patient, and headache in 1 patient. Two patients had a history of neurofibromatosis Type 2. Gamma Knife surgery was performed as primary management in 7 patients and after prior resection in 1 patient. The median and mean tumor volumes were 0.22 and 1.32 cm3 (range 0.03–7.4 cm3). A median margin dose of 12.5 Gy (range 11.0–13.0 Gy) was prescribed to the tumor margin. Clinical and imaging follow-up data were available for all 8 patients. Results Magnetic resonance imaging showed tumor regression in all patients. The progression-free period varied from 4 to 42 months, with a mean of 21 months. Over a mean of 23 months, 4 of the 5 patients with a trochlear schwannoma and symptoms of diplopia noted symptomatic improvement. No improvement was noted in the 2 patients with oculomotor nerve palsies. Headache was improved in the 1 patient with an abducent neuroma. Conclusions Gamma Knife surgery is an effective and minimally invasive approach capable of inactivating schwannomas originating from the oculomotor, trochlear, and abducent nerves. Accompanying trochlear function may improve. Longer follow-up and larger patient samples are needed to confirm the authors' initial observations.

Gamma Knife surgery for nonvestibular schwannomas: radiological and clinical outcomes

2012 ◽  
Vol 116 (1) ◽  
pp. 66-72 ◽  
Author(s):  
Mohamed Elsharkawy ◽  
Zhiyuan Xu ◽  
David Schlesinger ◽  
Jason P. Sheehan
Keyword(s):  
Gamma Knife ◽  
Maximum Dose ◽  
Progression Free Survival ◽  
Neurofibromatosis Type ◽  
Jugular Foramen ◽  
Gamma Knife Surgery ◽  
Tumor Control ◽  
Effective Treatment Option ◽  
Presenting Symptoms

Object Most intracranial schwannomas arise from cranial nerve (CN) VIII. Stereotactic radiosurgery is a mainstay of treatment for vestibular schwannomas. Intracranial schwannomas arising from other CNs are much less common. We evaluate the efficacy of Gamma Knife surgery on nonvestibular schwannomas including trigeminal, hypoglossal, abducent, facial, trochlear, oculomotor, glossopharyngeal, and jugular foramen tumors. Methods Thirty-six patients with nonvestibular schwannomas were treated at the University of Virginia Gamma Knife center from 1989 to 2008. The median patient age was 48 years (mean 45.6 years, range 10–72 years). Schwannomas arose from the following CNs: CN III (in 1 patient), CN IV (in 1), CN V (in 25), CN VI (in 2), CN VII (in 1), CN IX (in 1), and CN XII (in 3). In 2 patients, tumors arose from the jugular foramen. The median tumor volume was 2.9 cm3 (mean 3.3 cm3, range 0.07–8.8 cm3). The median margin dose was 13.5 Gy (range 9.3–20 Gy); the median maximum dose was 30 Gy (range 21.7–50.0 Gy). Results The mean and median follow-up times of 36 patients were 54 and 37 months, respectively (range 2–180 months). At the last radiological follow-up, the tumor size had decreased in 20 patients, remained stable in 9 patients, and increased in 7 patients. The 2-year actuarial progression-free survival was 91%. Higher maximum dose was statistically related to tumor control (p = 0.027). Thirty-three patients had adequate clinical follow-up. Among them, 21 patients had improvement in their presenting symptoms, 8 patients were stable after treatment with no worsening of their presenting symptoms, 2 patients developed new symptoms, and 1 patient experienced symptom deterioration. Notably, 1 patient with neurofibromatosis Type 2 developed new symptoms that were unrelated to the tumor treated with Gamma Knife surgery. Conclusions Gamma Knife surgery is a reasonably effective treatment option for patients with nonvestibular schwannomas. Patients require careful follow-up for tumor progression and signs of neurological deterioration.

STEREOTACTIC RADIOSURGERY FOR CAVERNOUS SINUS OR ORBITAL HEMANGIOMAS

Neurosurgery ◽  
2009 ◽  
Vol 65 (5) ◽  
pp. 914-918 ◽  
Author(s):  
Aftab A. Khan ◽  
Ajay Niranjan ◽  
Hideyuki Kano ◽  
Douglas Kondziolka ◽  
John C. Flickinger ◽  
...  
Keyword(s):  
Stereotactic Radiosurgery ◽  
Cavernous Sinus ◽  
Tumor Regression ◽  
Target Volume ◽  
Symptomatic Improvement ◽  
Primary Treatment ◽  
Vascular Tumors ◽  
Presenting Symptoms ◽  
Primary Treatment Modality

Abstract OBJECTIVE Hemangiomas are rare but highly vascular tumors that may develop in the cavernous sinus or orbit. These tumors pose diagnostic as well as therapeutic challenges to neurosurgeons during attempted removal. We analyzed our increasing experience using stereotactic radiosurgery (SRS). METHODS Eight symptomatic patients with hemangiomas underwent SRS between 1988 and 2007. The presenting symptoms included headache, orbital pain, diplopia, ptosis, proptosis and impaired visual acuity. The hemangiomas were located in either the cavernous sinus (7 patients) or the orbit (1 patient). Four patients underwent SRS as primary treatment modality based on clinical and imaging criteria. Four patients had previous microsurgical partial excision or biopsy. The median target volume was 6.8 mL (range, 2.5–18 mL). The median prescription dose delivered to the margin was 14.5 Gy (range, 12.5–19 Gy). The dose to the optic nerve in all patients was less than 9 Gy (range, 4.5–9 Gy). RESULTS The median follow-up period after SRS was 80 months (range, 40–127 months). Six patients had symptomatic improvement; 2 patients reported persistent diplopia. Follow-up imaging revealed tumor regression in 7 patients and no change in tumor volume in 1 patient. All the patients improved after SRS. CONCLUSION Our extended experience confirms that SRS is an effective management strategy for symptomatic intracavernous and intraorbital hemangiomas. Our study is the first long-term report on the safety and efficacy of SRS.

Results of Gamma Knife surgery for Cushing's disease

2013 ◽  
Vol 119 (6) ◽  
pp. 1486-1492 ◽  
Author(s):  
Jason P. Sheehan ◽  
Zhiyuan Xu ◽  
David J. Salvetti ◽  
Paul J. Schmitt ◽  
Mary Lee Vance
Keyword(s):  
Median Time ◽  
Gamma Knife ◽  
Cushing’S Disease ◽  
Cranial Nerves ◽  
Gamma Knife Surgery ◽  
High Rate ◽  
Cushing's Disease ◽  
Tumor Control

Object Cushing's disease is a challenging neuroendocrine disorder. Although resection remains the primary treatment option for most patients, the disease persists if there is residual or recurrent tumor. Stereotactic radiosurgery has been used to treat patients with persistent Cushing's disease after a prior resection. The authors report on the long-term risks and benefits of radiosurgery for Cushing's disease. Methods A retrospective review of a prospectively collected database of radiosurgery patients was undertaken at the University of Virginia. All patients with Cushing's disease treated with Gamma Knife surgery (GKS) were identified. Those without at least 12 months of clinical and radiological follow-up were excluded from this analysis. Rates of endocrine remission, tumor control, and adverse events were assessed. Statistical methods were used to identify favorable and unfavorable prognostic factors. Results Ninety-six patients with the required follow-up data were identified. The mean tumor margin dose was 22 Gy. The median follow-up was 48 months (range 12–209.8 months). At the last follow-up, remission of Cushing's disease occurred in 70% of patients. The median time to remission among all patients was 16.6 months (range 1–165.7 months). The median time to remission in those who had temporarily stopped taking ketoconazole at the time of GKS was 12.6 months, whereas it was 21.8 months in those who continued to receive ketoconazole (p < 0.012). Tumor control was achieved in 98% of patients. New loss of pituitary function occurred in 36% of patients. New or worsening cranial neuropathies developed in 5 patients after GKS, with the most common involving cranial nerves II and III. Conclusions Gamma Knife surgery offers a high rate of tumor control and a reasonable rate of endocrine remission in patients with Cushing's disease. The cessation of cortisol-lowering medications around the time of GKS appears to result in a more rapid rate of remission. Delayed hypopituitarism and endocrine recurrence develop in a minority of patients and underscore the need for long-term multidisciplinary follow-up.

scholarly journals Decreased Probability of Initial Pain Cessation in Classic Trigeminal Neuralgia Treated With Gamma Knife Surgery in Case of Previous Microvascular Decompression

Neurosurgery ◽  
2015 ◽  
Vol 77 (1) ◽  
pp. 87-95 ◽  
Author(s):  
Constantin Tuleasca ◽  
Romain Carron ◽  
Noémie Resseguier ◽  
Anne Donnet ◽  
Philippe Roussel ◽  
...  
Keyword(s):  
Trigeminal Neuralgia ◽  
Gamma Knife ◽  
Microvascular Decompression ◽  
Gamma Knife Surgery ◽  
University Hospital ◽  
Lower Probability ◽  
Patient Reported ◽  
History Of ◽  
Global Population

Abstract BACKGROUND: Microvascular decompression (MVD) is the reference technique for pharmacoresistant trigeminal neuralgia (TN). OBJECTIVE: To establish whether the safety and efficacy of Gamma Knife surgery for recurrent TN are influenced by prior MVD. METHODS: Between July 1992 and November 2010, 54 of 737 patients (45 of 497 with &gt;1 year of follow-up) had a history of MVD (approximately half also with previous ablative procedure) and were operated on with Gamma Knife surgery for TN in the Timone University Hospital. A single 4-mm isocenter was positioned in the cisternal portion of the trigeminal nerve at a median distance of 7.6 mm (range, 3.9–11.9 mm) anterior to the emergence of the nerve. A median maximum dose of 85 Gy (range, 70–90 Gy) was delivered. RESULTS: The median follow-up time was 39.5 months (range, 14.1–144.6 months). Thirty-five patients (77.8%) were initially pain free in a median time of 14 days (range, 0–180 days), much lower compared with our global population of classic TN (P = .01). Their actuarial probabilities of remaining pain-free without medication at 3, 5, 7, and 10 years were 66.5%, 59.1%, 59.1%, and 44.3%. The hypoesthesia actuarial rate at 1 year was 9.1% and remained stable until 12 years (median, 8 months). CONCLUSION: Patients with previous MVD showed a significantly lower probability of initial pain cessation compared with our global population with classic TN (P = .01). The toxicity was low (only 9.1% hypoesthesia); furthermore, no patient reported bothersome hypoesthesia. However, the probability of maintaining pain relief without medication was 44.3% at 10 years, similar to our global series of classic TN (P = .85).

Gamma Knife surgery in the treatment paradigm for foramen magnum meningiomas

2012 ◽  
Vol 117 (5) ◽  
pp. 864-873 ◽  
Author(s):  
Georgios Zenonos ◽  
Douglas Kondziolka ◽  
John C. Flickinger ◽  
Paul Gardner ◽  
L. Dade Lunsford
Keyword(s):  
Gamma Knife ◽  
Tumor Regression ◽  
Foramen Magnum ◽  
Gamma Knife Surgery ◽  
Symptom Improvement ◽  
Imaging Data ◽  
Safe Alternative ◽  
Primary Tumors ◽  
Treatment Paradigm

Object Microsurgical management of foramen magnum meningiomas (FMMs) can be associated with significant morbidity and mortality. Stereotactic radiosurgery may be an efficient and safe alternative treatment modality for such tumors. The object of this study was to increase the documented experience with Gamma Knife surgery (GKS) for FMMs and to delineate its role in an overall management paradigm. Methods The authors report on their experience with 24 patients harboring FMMs managed with GKS. Twelve patients had primary symptomatic tumors, 5 had asymptomatic but enlarging primary tumors, and 7 had recurrent or residual tumors after a prior surgery. Results Follow-up clinical and imaging data were available in 21 patients at a median follow-up of 47 months (range 3–128 months). Ten patients had measurable tumor regression, which was defined as an overall volume reduction > 25%. Eleven patients had no further tumor growth. Two patients died as a result of advanced comorbidities before follow-up imaging. One patient was living 8 years after GKS but had no clinical evaluation. Ten of 17 symptomatic patients with at least 6 months of follow-up had symptom improvement, and 7 remained clinically stable. Smaller tumors were more likely to regress. No patient suffered an adverse radiation effect after radiosurgery. Conclusions Gamma Knife surgery was a safe management strategy for small, minimally symptomatic, or growing FMMs as well as for residual tumors following conservative microsurgical removal.

scholarly journals Long-term follow-up studies of Gamma Knife surgery for patients with neurofibromatosis Type 2

2014 ◽  
Vol 121 (Suppl_2) ◽  
pp. 143-149 ◽  
Author(s):  
Shibin Sun ◽  
Ali Liu
Keyword(s):  
Gamma Knife ◽  
Neurofibromatosis Type ◽  
Hearing Preservation ◽  
Vestibular Schwannomas ◽  
Tumor Control ◽  
History Of ◽  
The Mean

ObjectThe aim of this study was to evaluate long-term clinical outcomes after Gamma Knife surgery (GKS) for patients with neurofibromatosis Type 2 (NF2) and the role of GKS in the management of NF2.MethodsFrom December 1994 through December 2008, a total of 46 patients (21 male, 25 female) with NF2 underwent GKS and follow-up evaluation for at least 5 years at the Gamma Knife Center of the Beijing Neurosurgical Institute. GKS was performed using the Leksell Gamma Knife Models B and C. The mean age of the patients was 30 years (range 13–59 years). A family history of NF2 was found for 9 (20%) patients. The NF2 phenotype was thought to be Wishart for 20 (44%) and Feiling-Gardner for 26 (56%) patients. Among these 46 patients, GKS was performed to treat 195 tumors (73 vestibular schwannomas and 122 other tumors including other schwannomas and meningiomas). For vestibular schwannomas, the mean volume was 5.1 cm3 (median 3.6 cm3, range 0.3–27.3 cm3), the mean margin dose was 12.9 Gy (range 10–14 Gy), and the mean maximum dose was 27.3 Gy (range 16.2–40 Gy). For other tumors, the mean volume was 1.7 cm3 (range 0.3–5.5 cm3), the mean margin dose was 13.3 Gy (range 11–14 Gy), and the mean maximum dose was 26.0 Gy (range 18.0–30.4 Gy). The median duration of follow-up was 109 months (range 8–195 months).ResultsFor the 73 vestibular schwannomas that underwent GKS, the latest follow-up MR images demonstrated regression of 30 (41%) tumors, stable size for 31 (43%) tumors, and enlargement of 12 (16%) tumors. The total rate of tumor control for bilateral vestibular schwannomas in patients with NF2 was 84%. Of the 122 other types of tumors that underwent GKS, 103 (85%) showed no tumor enlargement. The rate of serviceable hearing preservation after GKS was 31.9% (15/47). The actuarial rates for hearing preservation at 3 years, 5 years, 10 years, and 15 years were 98%, 93%, 44%, and 17%, respectively. Of the 46 patients, 22 (48%) became completely bilaterally deaf, 17 (37%) retained unilateral serviceable hearing, and 7 (15%) retained bilateral serviceable hearing. The mean history of the disease course was 12 years (range 5–38 years).ConclusionsGKS was confirmed to provide long-term local tumor control for small- to medium-sized vestibular schwannomas and other types of tumors, although vestibular schwannomas in patients with NF2 responded less well than did unilateral sporadic vestibular schwannomas. Phenotype is the most strongly predictive factor of final outcome after GKS for patients with NF2. The risk for loss of hearing is high, whereas the risk for other cranial nerve complications is low.

Gamma Knife surgery for subependymal giant cell astrocytomas

2011 ◽  
Vol 114 (3) ◽  
pp. 808-813 ◽  
Author(s):  
Kyung-Jae Park ◽  
Hideyuki Kano ◽  
Douglas Kondziolka ◽  
Ajay Niranjan ◽  
John C. Flickinger ◽  
...  
Keyword(s):  
Giant Cell ◽  
Gamma Knife ◽  
Tumor Regression ◽  
Local Tumor Control ◽  
Gamma Knife Surgery ◽  
Tumor Control ◽  
Subtotal Resection ◽  
Subependymal Giant Cell Astrocytoma ◽  
Large Tumor

Object The authors report their experience of using Gamma Knife surgery (GKS) in patients with subependymal giant cell astrocytoma (SEGA). Methods Over a 20-year period, the authors identified 6 patients with SEGAs who were eligible for GKS. The median patient age was 16.5 years (range 7–55 years). In 4 patients, GKS was used as a primary management therapy. One patient underwent radiosurgery for recurrent tumors after prior resection, and in 1 patient GKS was used as an adjunct after subtotal resection. The median tumor volume at GKS was 2.75 cm3 (range 0.7–5.9 cm3). A median radiation dose of 14 Gy (range 11–20 Gy) was delivered to the tumor margin. Results The median follow-up duration was 73 months (range 42–90 months). Overall local tumor control was achieved in 4 tumors (67%) with progression-free periods of 24, 42, 57, and 66 months. Three tumors regressed and one remained unchanged. In 2 patients the tumors progressed, and in 1 of these patients the lesion was managed by repeated GKS with subsequent tumor regression. The other relatively large tumor (5.9 cm3) was excised 9 months after GKS. The progression-free period for all GKS-managed tumors varied from 9 to 66 months. There were no cases of hydrocephalus or GKS-related morbidity. Conclusions Gamma Knife surgery may be an additional minimally invasive management option for SEGA in a patient who harbors a small but progressively enlarging tumor when complete resection is not safely achievable. It may also benefit patients with a residual or recurrent tumor that has progressed after surgery.

Gamma knife surgery for glomus jugulare tumors: an intermediate report on efficacy and safety

2005 ◽  
Vol 102 (Special_Supplement) ◽  
pp. 241-246 ◽  
Author(s):  
Jason Sheehan ◽  
Douglas Kondziolka ◽  
John Flickinger ◽  
L. Dade Lunsford
Keyword(s):  
Gamma Knife ◽  
Cranial Nerves ◽  
Gamma Knife Surgery ◽  
Long Term Results ◽  
Tumor Control ◽  
Content Type ◽  
Glomus Jugulare ◽  
Cranial Nerve Palsies ◽  
Fine Print

Object. Glomus jugulare tumors are rare tumors that commonly involve the middle ear, temporal bone, and lower cranial nerves. Resection, embolization, and radiation therapy have been the mainstays of treatment. Despite these therapies, tumor control can be difficult to achieve particularly without undo risk of patient morbidity or mortality. The authors examine the safety and efficacy of gamma knife surgery (GKS) for glomus jugulare tumors. Methods. A retrospective review was undertaken of the results obtained in eight patients who underwent GKS for recurrent, residual, or unresectable glomus jugulare tumors. The median radiosurgical dose to the tumor margin was 15 Gy (range 12–18 Gy). The median clinical follow-up period was 28 months, and the median period for radiological follow up was 32 months. All eight patients demonstrated neurological stability or improvement. No cranial nerve palsies arose or deteriorated after GKS. In the seven patients in whom radiographic follow up was obtained, the tumor size decreased in four and remained stable in three. Conclusions. Gamma knife surgery would seem to afford effective local tumor control and preserves neurological function in patients with glomus jugulare tumors. If long-term results with GKS are equally efficacious, the role of stereotactic radiosurgery will expand.

Gamma knife surgery for intracranial cavernous hemangioma

2005 ◽  
Vol 102 ◽  
pp. 102-106 ◽  
Author(s):  
Moo Seong Kim ◽  
Se Young Pyo ◽  
Young Gyun Jeong ◽  
Sun Il Lee ◽  
Yong Tae Jung ◽  
...  
Keyword(s):  
Basal Ganglia ◽  
Gamma Knife ◽  
Cavernous Hemangioma ◽  
Gamma Knife Surgery ◽  
Content Type ◽  
Presenting Symptoms ◽  
Cavernous Hemangiomas ◽  
The Mean ◽  
Fine Print

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.

Gamma Knife surgery for the management of glomus tumors: a multicenter study

2012 ◽  
Vol 117 (2) ◽  
pp. 246-254 ◽  
Author(s):  
Jason P. Sheehan ◽  
Shota Tanaka ◽  
Michael J. Link ◽  
Bruce E. Pollock ◽  
Douglas Kondziolka ◽  
...  
Keyword(s):  
Tumor Progression ◽  
Gamma Knife ◽  
Cranial Nerve ◽  
Cranial Nerves ◽  
Gamma Knife Surgery ◽  
High Rate ◽  
Tumor Control ◽  
Pulsatile Tinnitus ◽  
Glomus Tumors

Object Glomus tumors are rare skull base neoplasms that frequently involve critical cerebrovascular structures and lower cranial nerves. Complete resection is often difficult and may increase cranial nerve deficits. Stereotactic radiosurgery has gained an increasing role in the management of glomus tumors. The authors of this study examine the outcomes after radiosurgery in a large, multicenter patient population. Methods Under the auspices of the North American Gamma Knife Consortium, 8 Gamma Knife surgery centers that treat glomus tumors combined their outcome data retrospectively. One hundred thirty-four patient procedures were included in the study (134 procedures in 132 patients, with each procedure being analyzed separately). Prior resection was performed in 51 patients, and prior fractionated external beam radiotherapy was performed in 6 patients. The patients' median age at the time of radiosurgery was 59 years. Forty percent had pulsatile tinnitus at the time of radiosurgery. The median dose to the tumor margin was 15 Gy. The median duration of follow-up was 50.5 months (range 5–220 months). Results Overall tumor control was achieved in 93% of patients at last follow-up; actuarial tumor control was 88% at 5 years postradiosurgery. Absence of trigeminal nerve dysfunction at the time of radiosurgery (p = 0.001) and higher number of isocenters (p = 0.005) were statistically associated with tumor progression–free tumor survival. Patients demonstrating new or progressive cranial nerve deficits were also likely to demonstrate tumor progression (p = 0.002). Pulsatile tinnitus improved in 49% of patients who reported it at presentation. New or progressive cranial nerve deficits were noted in 15% of patients; improvement in preexisting cranial nerve deficits was observed in 11% of patients. No patient died as a result of tumor progression. Conclusions Gamma Knife surgery was a well-tolerated management strategy that provided a high rate of long-term glomus tumor control. Symptomatic tinnitus improved in almost one-half of the patients. Overall neurological status and cranial nerve function were preserved or improved in the vast majority of patients after radiosurgery.

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