Jason P. Sheehan
Jason P. Sheehan
Neurosurgical training is critical in providing residents with the skill set, knowledge, and confidence to perform challenging neurosurgical procedures. Radiosurgery, which neurosurgeons helped define and refine, differs from more traditional, open neurosurgical approaches. This study evaluates the opinions of residents on current radiosurgical training and the effect of a focused educational course on those residents.
The American Association of Neurological Surgeons sponsored a 3-day course focused on intracranial and spinal radiosurgery. Senior-level residents were nominated by US program directors to participate in the course. Twenty-eight residents from distinct training programs were surveyed before and after the course to discern current training practices in radiosurgery and the effect of the focused educational program. The median training level of the participants was postgraduate Year 5 (mean 5.3 years, range 3–7 years).
Two-thirds of residents reported that their training institutions had no formal radiosurgery rotation. Twenty-five percent planned to obtain postresidency fellowship training that would include radiosurgery. Before the course, 79% of the residents expected to include radiosurgery in their practice. However, prior to the course, those describing themselves as “very uncomfortable” with performing intracranial or spinal radiosurgery were 33.3 and 45.8%, respectively. After the course, mean self-assessment scores for understanding the indications and performing intracranial radiosurgery increased by 43 and 89%, respectively. The mean scores for understanding the indications and comfort with performing spinal radiosurgery increased by 79 and 200%, respectively. Following the course, there was a 12.3% increase in the number of residents planning to perform radiosurgery following residency.
Current neurosurgical residents appear uneasy about their grasp of radiosurgical indications and their ability to perform the procedure. Focused training courses sponsored by professional societies may improve resident education and training in this area of neurosurgery, which has a skill set and basis of knowledge different from traditional open neurosurgical procedures. Further evaluation of the radiosurgical training process for residents must be performed so as to ensure competency and sufficient workforce to meet expanding demands for neurosurgeons performing radiosurgery in a multidisciplinary climate.
Alana Tooze and Jason P. Sheehan
Pituitary adenomas and the treatment required for the underlying neuropathology have frequently been associated with cognitive dysfunction. However, the mechanisms for these impairments remain the subject of much debate. The authors evaluated cognitive outcomes in patients treated with or without Gamma Knife radiosurgery (GKRS) for an underlying pituitary adenoma.
This was a retrospective, institutional review board–approved, single-institution study. A total of 51 patients (23 male, 28 female) treated for pituitary adenoma were included in this neurocognitive study. Twenty-one patients underwent GKRS following transsphenoidal surgery, 22 patients were treated with transsphenoidal surgery alone, and eight patients were conservatively managed or were treated with medical management alone. Comparisons using psychometric tests of general intellectual abilities, memory, and executive functions were made between the treatment groups, between male and female patients, and between patients with Cushing’s disease and those with nonfunctioning adenoma (NFA).
The entire patient sample, the NFA group, and the GKRS group scored significantly below expected on measures of both immediate and delayed memory, particularly for visually presented information (p ≤ 0.05); however, there were no significant differences between the patients with Cushing’s disease and those with NFA (t ≤ 0.56, p ≥ 0.52). In those who underwent GKRS, memory scores were not significantly different from those in the patients who did not undergo GKRS (t ≤ 1.32, p ≥ 0.19). Male patients across the sample were more likely to demonstrate impairments in both immediate memory (t = −3.41, p = 0.003) and delayed memory (t = −3.80, p = 0.001) than were female patients (t ≤ 1.09, p ≥ 0.29). There were no impairments on measures of general intellectual functioning or executive functions in any patient group. The potential contributions of tumor size and hormone levels are discussed.
Overall, pituitary adenoma patients demonstrated relative impairment in anterograde memory. However, GKRS did not lead to adverse effects for immediate or delayed memory in pituitary adenoma patients. Cognitive assessment of pituitary adenoma patients is important in their longitudinal care.
James P. Caruso and Jason P. Sheehan
At the peak of his career, Walter J. Freeman II was a celebrated physician and scientist. He served as the first chairman of the Department of Neurology at George Washington University and was a tireless advocate of surgical treatment for mental illness. His eccentric appearance, engaging personality during interviews, and theatrical demonstrations of his surgical techniques gained him substantial popularity with local and national media, and he performed more than 3000 prefrontal and transorbital lobotomies between 1930 and 1960. However, poor patient outcomes, unfavorable portrayals of the lobotomy in literature and film, and increased regulatory scrutiny contributed to the lobotomy’s decline in popularity. The development of antipsychotic medications eventually relegated the lobotomy to rare circumstances, and Freeman’s reputation deteriorated. Today, despite significant advancements in technique, oversight, and ethical scrutiny, neurosurgical treatment of mental illness still carries a degree of social stigma.
This review presents a historical account of Walter Freeman’s life and career, and the popularization of the lobotomy in the US. Additionally, the authors pay special attention to the influence of popular literature and film on the public’s perception of psychosurgery. Aided by an understanding of this pivotal period in medical history, neurosurgeons are poised to confront the ethical and sociological questions facing psychosurgery as it continues to evolve.
Jason P. Sheehan and Jay Jagannathan
Intracranial radiosurgery has been proved effective for the treatment of brain metastasis. The treatment of paraspinal and spinal metastasis with spinal radiosurgery represents a natural extension of the principles of intracranial radiosurgery. However, spinal radiosurgery is a far more complicated process than intracranial radiosurgery. Larger treatment volumes, numerous organs at risk, and the inability to utilize rigid, frame-based immobilization all contribute to the substantially more complex process of spinal radiosurgery.
Beyond the convenience of a shorter duration of treatment for the patient, spinal radiosurgery affords a greater biological equivalent dose to a metastatic lesion than conventional radiotherapy fractionation schemes. This appears to translate into a high rate of tumor control and fast pain relief for patients. The minimally invasive nature of this approach is consistent with trends in open spinal surgery and helps to maintain or improve a patient's quality of life. Spinal radiosurgery has expanded the neurosurgical treatment armamentarium for patients with spinal and paraspinal metastasis.
Jason P. Sheehan
Christopher P. Cifarelli, David J. Schlesinger, and Jason P. Sheehan
Gamma Knife surgery (GKS) has become a significant component of neurosurgical treatment for recurrent secretory and nonsecretory pituitary adenomas. Although the long-term risks of visual dysfunction following microsurgical resection of pituitary adenomas has been well studied, the comparable risk following radiosurgery is not well defined. This study evaluates the long-term risks of ophthalmological dysfunction following GKS for recurrent pituitary adenomas.
An analysis of 217 patients with recurrent secretory (n = 131) and nonsecretory (n = 86) pituitary adenomas was performed to determine the incidence of and risk factors for subsequent development of visual dysfunction. Patients underwent ophthalmological evaluation as part of post-GKS follow-up to assess for new or worsened cranial nerve II, III, IV, or VI palsies. The median follow-up duration was 32 months. The median maximal dose was 50 Gy, and the median peripheral dose was 23 Gy. A univariate analysis was performed to assess for risk factors of visual dysfunction post-GKS.
Nine patients (4%) developed new visual dysfunctions, and these occurred within 6 hours to 34 months following radiosurgery. None of these 9 patients had tumor growth on post-GKS neuroimaging studies. Three of these patients had permanent deficits whereas in 6 the deficits resolved. Five of the 9 patients had prior GKS or radiotherapy, which resulted in a significant increase in the incidence of cranial nerve dysfunction (p = 0.0008). An increased number of isocenters (7.1 vs 5.0, p = 0.048) was statistically related to the development of visual dysfunction. Maximal dose, margin dose, optic apparatus dose, tumor volume, cavernous sinus involvement, and suprasellar extension were not significantly related to visual dysfunction (p >0.05).
Neurological and ophthalmological assessment in addition to routine neuroimaging and endocrinological follow-up are important to perform following GKS. Patients with a history of radiosurgery or radiation therapy are at higher risk of cranial nerve deficits. Also, a reduction in the number of isocenters delivered, along with volume treated, particularly in the patients with secretory tumors, appears to be the most reasonable strategy to minimize the risk to the visual system when treating recurrent pituitary adenomas with stereotactic radiosurgery.
Adomas Bunevicius, Darrah Sheehan, Mary Lee Vance, David Schlesinger, and Jason P. Sheehan
Stereotactic radiosurgery (SRS) is used for the management of residual or recurrent Cushing’s disease (CD). Increasing experience and technological advancements of Gamma Knife radiosurgery (GKRS) systems can impact the outcomes of CD patients. The authors evaluated the association of their center’s growing experience and the era in which GKRS was performed with treatment success and adverse events in patients with CD.
The authors studied consecutive patients with CD treated with GKRS at the University of Virginia since installation of the first Gamma Knife system in March 1989 through August 2019. They compared endocrine remission and complication rates between patients treated before 2000 (early cohort) and those who were treated in 2000 and later (contemporary cohort).
One hundred thirty-four patients with CD underwent GKRS during the study period: 55 patients (41%) comprised the early cohort, and 79 patients (59%) comprised the contemporary cohort. The contemporary cohort, compared with the early cohort, had a significantly greater treatment volume, radiation prescription dose, maximal dose to the optic chiasm, and number of isocenters, and they more often had cavernous sinus involvement. Endocrine remission rates were higher in the contemporary cohort when compared with the early cohort (82% vs 66%, respectively; p = 0.01). In a Cox regression analysis adjusted for demographic, clinical, and SRS characteristics, the contemporary GKRS cohort had a higher probability of endocrine remission than the early cohort (HR 1.987, 95% CI 1.234–3.199; p = 0.005). The tumor control rate, incidence of cranial nerve neuropathy, and new anterior pituitary deficiency were similar between the two groups.
Technological advancements over the years and growing center experience were important factors for improved endocrine remission rates in patients with CD. Technological aspects and results of contemporary Gamma Knife systems should be considered when counseling patients, planning treatment, and reporting treatment results. Studies exploring the learning curve for GKRS are warranted.