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Dive into the research topics where George J. Kaptain is active.

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Featured researches published by George J. Kaptain.


Neurosurgery | 2002

Pituitary surgery: transsphenoidal approach.

John A. Jane; Kamal Thapar; George J. Kaptain; Nicholas Maartens; Edward R. Laws

THE TRANSSPHENOIDAL APPROACH for sellar tumors has evolved significantly since it was described initially during the first decade of the 20th century. The approach currently incorporates technological advancements and refinements in patient selection, operative technique, and postoperative care. Although many of these innovations are considered indispensable, the operative technique, as performed by contemporary neurosurgeons, is not standardized. This variability is a reflection of surgeon’s preference, the lessons of experience, and the bias inherent in neurosurgical training. The methods and preferences described herein embody the distillation of an experience gained from 3900 transsphenoidal operations.


Neurosurgery | 2001

Cranial base reconstruction after transsphenoidal surgery with bioabsorbable implants.

George J. Kaptain; David A. Vincent; Edward R. Laws

OBJECTIVE Reconstruction of the cranial base is often necessary after transsphenoidal surgery to prevent the occurrence of cerebrospinal fluid rhinorrhea and to maintain anatomic integrity. In most cases, sellar packing (fat, muscle, gelatin sponge) may be supported by bone or cartilage harvested at the time of surgery. The use of synthetic material, however, becomes desirable in cases in which an autograft is not available. Low-molecular-weight polylactide implants may serve as an effective alternative because they are immunologically inert, magnetic resonance imaging-compatible, and easily contoured to custom-fit a defect. METHODS AND RESULTS MacroSorb (MacroPore, San Diego, CA) absorbable plates are made from amorphous 70:30 poly (l-lactide-co-d,l-lactide) polymers. Implants are malleable at temperatures of 70°C and solidify at room or body temperature; plates are resorbed in 18 months. CONCLUSION Polylactide polymer implants are effective adjuncts in transsphenoidal surgery when cranial base reconstruction is necessary and when an endogenous osseous or cartilaginous graft is unavailable.


Drugs & Aging | 2000

Subarachnoid haemorrhage: Epidemiology, risk factors, and treatment options

George J. Kaptain; Giuseppe Lanzino; Neal F. Kassell

The present review focuses on subarachnoid haemorrhage (SAH) secondary to the rupture of an intracranial aneurysm, a condition with a high case fatality rate. Additionally, many of the surviving patients are left with significant disabilities. Risk factors for aneurysmal SAH include both genetic and acquired conditions. The most common presenting symptom is sudden onset of severe headache. Since headache is very common in the general population, it is not unusual that SAH is misdiagnosed at its onset with often catastrophic consequences. Unlike other acute neurological disorders such as brain injury, in which patient outcome is closely related to the extent of the injury occurring at the time of the trauma, patients with aneurysmal SAH are at risk of subsequent deterioration from ‘avoidable’ complications such as rebleed, vasospasm, hydrocephalus, and several other non-neurological general medical complications. Thus, the critical care management of the patient with SAH is of utmost importance in order to maximise the chances of satisfactory recovery. Although surgical clipping of the ruptured aneurysm remains the gold standard therapy, with the continuing refinement of endovascular techniques, a new, ‘less invasive’ option is now available, especially for patients considered poor surgical candidates.


Neurosurgery | 2000

Congenital absence of a cervical pedicle: report of two cases and review of the literature.

Jason P. Sheehan; George J. Kaptain; Jonas M. Sheehan; John A. Jane

OBJECTIVE AND IMPORTANCEThe congenital absence of a cervical pedicle is a rare clinical entity. Patients with this anomaly tend to present with cervical pain or after a traumatic incident. Initial evaluations with conventional radiography frequently lead to misinterpretation and misguided intervention. We report two cases of absent cervical pedicles and describe the presentation, diagnosis, and treatment of these patients. Moreover, we review the literature on this clinical entity. CLINICAL PRESENTATIONThe first patient was a 4-year-old boy who presented with neck pain after falling off a trampoline. His neurological examination did not reveal any focal abnormalities, but radiographs were thought to be consistent with a right, C4–C5, unilateral, jumped facet. The second patient was a 27-year-old woman who presented with severe neck, back, and left upper extremity pain and paresthesias after an alleged incident of spousal abuse. Her neurological examination results were remarkable for left upper extremity weakness and hemibody sensory changes. Conventional radiographs were thought to reveal a left, C3–C4, unilateral, locked facet. INTERVENTIONFor both patients, reduction attempts were made with Gardner-Wells tongs and traction. After failure to achieve adequate reduction, evaluations using two-dimensional computed tomography confirmed congenitally absent cervical pedicles. Both patients were ultimately treated conservatively and experienced resolution of their presenting symptoms. CONCLUSIONThe congenital absence of a cervical pedicle is a rare entity that is frequently misdiagnosed. Diagnoses can be accurately confirmed with two-dimensional computed tomography. Conservative treatment resulted in successful management of this clinical entity.


Surgical Neurology | 1999

Posterior inferior cerebellar artery aneurysms associated with posterior fossa arteriovenous malformation: Report of five cases and literature review

George J. Kaptain; Giuseppe Lanzino; Huy M. Do; Neal F. Kassell

BACKGROUND The association of posterior inferior cerebellar artery (PICA) aneurysms with posterior fossa arteriovenous malformation (AVM) is uncommon. Over the past 3 years, five patients with this condition were treated at this institution. A review of the clinical history of these and other reported cases has illuminated common threads in the presentation, treatment, and outcome of these lesions. METHODS The findings of 27 patients (5 from our institution and 22 from the medical literature) with PICA aneurysms associated with AVMs were reviewed. RESULTS Eighty-four percent of individuals presented with sub-arachnoid hemorrhage (SAH); 89% of these episodes resulted from aneurysm rupture documented by either intraoperative inspection or autopsy. All aneurysms were located on a feeding artery to the AVM, and 81% originated from distal portions of PICA. The majority of patients presented with Hunt & Hess grade I SAH; all patients who presented with hemorrhage were treated surgically. Surgical strategy was directed both to secure the aneurysm and to resect the AVM during the course of a single procedure. Although four individuals either died on admission or in the perioperative period, overall outcome was excellent or good in 82% of patients. CONCLUSIONS PICA aneurysms associated with AVMs most often involve the distal segments of the artery. Patients usually present with SAH secondary to aneurysmal rupture. Surgical clipping of the aneurysm and excision of the AVM is possible in a single procedure with minimal morbidity. Overall prognosis is favorable in 80% of the cases.


Neurosurgery | 2011

Management and implications of intraoperative cerebrospinal fluid leak in transnasoseptal transsphenoidal microsurgery.

George J. Kaptain; Adam S. Kanter; David K. Hamilton; Edward R. Laws

BACKGROUND: Nonvascularized autologous grafts used for sellar reconstruction in transseptal transsphenoidal surgery are commonly applied in the setting of intraoperative cerebrospinal fluid (CSF) leak and have been shown to be effective in preventing postoperative complications. OBJECTIVE: To assess the clinical implications of intraoperative CSF leak, to evaluate the efficacy of repair techniques using autologous nonvascularized materials, and to analyze the nature and timing of failures. These data may serve as a basis for assessing the utility of innovations in techniques and implant technologies. METHODS: A review was conducted of 257 consecutive patients who underwent transsphenoidal surgery that was complicated by intraoperative CSF leak from 1995 to 2001. Sellar reconstruction was performed with autologous materials except in reoperations in which septal materials were not available; lumbar drain catheters were used selectively. RESULTS: Six of the 257 patients (2.3%) developed postoperative CSF rhinorrhea occurring an average of 6.6 days after surgery. All 6 underwent reoperation, with 5 of 6 managed with operative lumbar drainage. Bacterial meningitis developed in 3 of 257 (1.2%). Worsening in visual function occurred in 8 of 257 (3.1%), with 1 of 257 (0.3%) suffering from permanent worsening of visual function. Additional surgery was performed in 2 of these patients, resulting in successful reversal of visual loss. Ten of 257 patients (3.9%) developed a subcutaneous hematoma at the fat graft harvest site, with 1 patient requiring surgical re-exploration. CONCLUSIONS: Watertight closure of the sella with autologous materials is effective in preventing postoperative rhinorrhea. Complications specific to the technique include graft site hematoma (4%) and rare instances of visual loss caused by optic nerve compression.


Neurosurgery | 2010

Gamma knife radiosurgery for dural arteriovenous fistulas.

Christopher P Cifarelli; George J. Kaptain; Chun-Po Yen; David Schlesinger; Jason P. Sheehan

BACKGROUND:The current management of intracranial dural arteriovenous fistulas (dAVFs) incorporates a multimodal approach involving microneurosurgery, endovascular embolization, and radiosurgery. OBJECTIVE:To explore the role of Gamma Knife radiosurgery for dAVFs. METHODS:The series includes patients with dAVFs who had Gamma Knife radiosurgery at the University of Virginia Medical Center between 1989 and 2005 with clinical follow-up through 2008. Medical records were reviewed to obtain clinical history, demographic data, and dosimetry. Radiographic records provided the location and anatomy of the dAVFs. Follow-up angiography was performed 2 to 3 years after treatment, with cure defined as complete obliteration of fistulous flow. Follow-up for clinical symptomology and quality of life was obtained from direct patient and primary physician questionnaires. RESULTS:Fifty-five patients underwent Gamma Knife radiosurgery for dAVFs during the study period. Twenty patients (36%) presented with intracranial hemorrhage before radiosurgery. Gamma Knife radiosurgery was preceded by craniotomy for microneurosurgical ablation in 11 patients (20%) or endovascular embolization in 36 patients (65%). Follow-up angiography was performed on 46 patients (83%) with documented obliteration in 30 patients (65%). Patients lost to follow-up were classified as treatment failures, adjusting the range of efficacy from 65% to 54%. Three patients (5%) suffered a posttreatment hemorrhage during the follow-up period, but no new permanent neurological deficits resulted from these events. CONCLUSION:Gamma Knife radiosurgery is an effective adjunct therapy for dAVFs with persistence of flow after open neurosurgical resection or endovascular treatment while still maintaining a role in nonaggressive dAVFs not amenable to either surgery or embolization.


Surgical Neurology | 1999

Secondary gain influences the outcome of lumbar but not cervical disc surgery

George J. Kaptain; Christopher I. Shaffrey; Tord D. Alden; Jacob N Young; Edward R. Laws; Richard Whitehill

BACKGROUND The expectation of monetary compensation has been associated with poor outcomes in lumbar discectomy, fueling a reluctance among surgeons to treat workers compensation cases. This issue, however, has not been investigated in patients undergoing cervical disc surgery. This study analyzes the relationship between economic forms of secondary gain and surgical outcome in a group of patients with common pay scales, retirement plans, and disability programs. METHODS All procedures were performed at the Portsmouth Naval Medical Center between 1993 and 1995; active duty military servicepersons who were treated for cervical radiculopathy were prospectively included. Clinical, demographic, and financial factors were analyzed to determine which were predictive for outcome. Financial data were used to create a compensation incentive (CI) which is proportional to the rank, years of service, potential disability, retirement eligibility, and base pay and reflects the monetary incentive of disability. The results of cervical surgery were compared to a previously reported companion population of patients treated for lumbar disc disease. A good outcome is defined as a return to active duty, whereas a referral for disability is considered a poor surgical result. RESULTS One hundred percent follow-up was obtained for 269 patients who were treated with 307 cervical operations. Only 16% (43/269) of cervical patients received disability, whereas 24.7% (86/348) of lumbar patients obtained a poor result (p = 0.0082). Although economic forms of secondary gain were not associated with outcome in cervical disease, both the position (p = 0.002) and duration of an individuals military career were significant factors (p = 0.02). Of the medical variables tested, multilevel surgery (p = 0.03) and revision operations at the same level (p = 0.03) were associated with referral for medical discharge. CONCLUSIONS Secondary gain in the form of economic compensation influences outcome in lumbar but not cervical disc surgery; this observation may in part account for the success of cervical surgery relative to lumbar discectomy. Social factors that are independent of the anticipation of economic compensation seem to influence the outcome of cervical disc surgery.


Neurosurgery | 1998

Successful excision of a large immature teratoma involving the cranial base: report of a case with long-term follow-up.

Giuseppe Lanzino; George J. Kaptain; John A. Jane; Kant Y. Lin

OBJECTIVE AND IMPORTANCE Massive congenital intracranial teratomas with extracranial extension are rare. The prognosis in these cases has been poor, with stillbirth or immediate postpartum death as the usual outcome. With recent advances in fetal monitoring, neonatal care, and surgical techniques used for the management of complex tumors of the cranial base, some of these lesions may now be amenable to radical surgical resection and then immediate craniofacial reconstruction. CLINICAL PRESENTATION A neonate with a large congenital immature teratoma involving the entire left side of the cranium and face was evaluated at our institution 1 day after birth. INTERVENTION Total resection of the mass and then immediate reconstruction of the deformed orbit, maxilla, and mandible were performed at 9 days of age. Additional operations on the midface and mandible to allow for a functional bite were subsequently required as the child developed during the next 2 years. Four years after resection, the patient exhibited a reasonable cosmetic result and only mild developmental delay. CONCLUSION We conclude that acceptable functional and cosmetic outcomes can be achieved by early intervention, consisting of radical resection and immediate craniofacial reconstruction, in some neonates with massive congenital craniofacial teratomas.


Pituitary | 1999

Estrogen Receptors in Prolactinomas: A Clinico-Pathological study

George J. Kaptain; Nathan E. Simmons; Tord D. Alden; Maria Beatriz Lopes; Mary Lee Vance; Edward R. Laws

Background: Antiestrogens are effective in the treatment of estrogen receptor (ER) positive breast carcinoma. The use of antiestrogen therapy in pituitary adenomas, however, has not been explored. This study attempted to identify a population who may benefit from antiestrogen therapy.Materials & Methods: Prolactinomas from 29 patients (10 men, 19 women) were analyzed for ER and Ki-67 labeling index using immunohistochemistry. Nine of the 19 women were either amenorrheic or had not received exogenous estrogen for at least one year. Ten women were menstruating either spontaneously or as a result of estrogen administration. Factors including age, serum prolactin level, tumor size, evidence of tumor invasiveness and recurrence of tumor were evaluated to determine if they were predictive of ER expression.Results: Tumors from 6/10 (60%) men were positive for ER. Among women who were having menses, 9/10 (90%) tumors were positive, whereas 6/9 (67%) tumors from amenorrheic women were positive. Statistical analysis revealed that none of the variables: gender, age, menstrual status, Ki-67 proliferative rate, exposure to dopamine agonists, preoperative prolactin level, tumor size, or invasiveness was predictive for the presence of the receptor. The incidence of ER, however, was significantly reduced in recurrent tumors (p=0.03).Conclusions: ER expression is less likely in recurrent tumors. The efficacy of ER antagonists cannot be inferred by gender or estrogen exposure.

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Manish K. Aghi

University of California

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Jana Portnow

City of Hope National Medical Center

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Santosh Kesari

University of California

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Tom Mikkelsen

Henry Ford Health System

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