Howard Colman, Manfred Westphal and John H. Sampson
John H. Sampson
John H. Sampson and Blaine S. Nashold Jr.
✓ One patient with a pontine infarct due to a fusiform basilar artery aneurysm and one with an arteriovenous malformation within the tectum of the mesencephalon developed intractable facial pain. This pain was relieved in both patients by radiofrequency lesions in the dorsal root entry zone of the trigeminal nucleus caudalis.
John H. Sampson
Eric M. Gabriel, John H. Sampson and Robert H. Wilkins
✓ Complete excision of a cerebral arteriovenous malformation (AVM) should eliminate the future risk of an associated intracranial hemorrhage. Because total removal of an AVM may be difficult to assess at the time of surgery, postoperative angiography has become the accepted standard for documenting that the removal has been accomplished. However, even angiographically confirmed excision of an AVM does not completely ensure against rebleeding. Regrowth of an AVM with subsequent hemorrhage can occur. This has been documented in children and is attributed to forces acting on the immature vasculature of these younger patients. The authors report the case of an older patient whose AVM recurred when he was 28 years of age, despite an angiographically proven complete excision, and emphasize that, even in adults, angiographic documentation of total removal does not always eliminate the risk of reformation of an AVM.
John H. Sampson, James H. Carter JR., Allan H. Friedman and Hilliard F. Seigler
Brain metastases are a common and devastating complication in patients with malignant melanoma. Therapeutic options for these patients are limited, and the prognosis is usually poor.
Object. A retrospective review of 6953 patients with melanoma treated at a single institution was undertaken to identify demographic factors associated with the development of clinically significant brain metastases in 702 of these patients and to determine the factors influencing the prognosis of this population to permit more informed recommendations regarding surgical therapy.
Methods. Factors found to be associated with the development of brain metastases included male gender, primary lesions located on mucosal surfaces or on the skin of the trunk or head and neck, thick or ulcerated primary lesions, and histological findings of acral lentiginous or nodular lesions. The overall median survival time of all patients with brain metastases was 113.2 days, and these metastases contributed to the death of 94.5% of the patients in this group. Patients with primary lesions located in the head or neck region had a significantly shorter survival time relative to other patients with brain metastases, whereas patients with a single brain metastasis, patients without lung or multiple other visceral metastases, and patients whose initial presentation with melanoma included a brain metastasis had a significantly better prognosis. The small group of patients who survived for more than 3 years was characterized by the presence of a surgically treated, single brain metastasis in the absence of other visceral metastatic disease.
Conclusions. Although most patients with brain metastases resulting from melanoma have a dismal prognosis, some who are likely to survive for longer periods can be identified. In these patients surgical resection can significantly prolong meaningful survival. The decision to recommend surgery should be based primarily on the resectability of the brain metastases and on the status and number of other organs with metastatic lesions.
John H. Sampson, Michael M. Haglund, Allan H. Friedman and Matthew G. Ewend
Bryan D. Choi, Michael R. DeLong, David M. DeLong, Allan H. Friedman and John H. Sampson
The purpose of this study was to report the prevalence of neurosurgeons with both medical degrees (MDs) and doctorates (PhDs) at top-ranked US academic institutions and to assess whether the additional doctorate education is associated with substantive career involvement in academia as well as greater success in procuring National Institutes of Health (NIH) research funding compared with an MD-only degree.
The authors reviewed the training of neurosurgeons across the top 10 neurosurgery departments chosen according to academic impact (h index) to examine whether MD-PhD training correlated significantly with career outcomes in academia.
Six hundred thirteen neurosurgery graduates and residents between the years 1990 and 2012 were identified for inclusion in this analysis. Both MD and PhD degrees were held by 121 neurosurgeons (19.7%), and an MD alone was held by 492. Over the past 2 decades, MD-PhD trainees represented a gradually increasing percentage of neurosurgeons, from 10.2% to 25.7% (p < 0.01). Of the neurosurgeons with MD-PhD training, a greater proportion had appointments in academic medicine compared with their MD-only peers (73.7% vs 52.3%, p < 0.001). Academic neurosurgeons with both degrees were also more likely to have received NIH funding (51.9% vs 31.8%, p < 0.05) than their single-degree counterparts in academia. In a national analysis of all active NIH R01 grants awarded in neurosurgery, MD-PhD investigators held a disproportionate number, more than 4-fold greater than their representation in the field.
Dual MD-PhD training is a significant factor that may predict active participation in and funding for research careers among neurological surgeons at top-ranked academic institutions. These findings and their implications are of increasing relevance as the population of neurosurgeons with dual-degree training continues to rise.
John H. Sampson, Robert E. Cashman, Blaine S. Nashold Jr. and Allan H. Friedman
✓ This review was undertaken to determine the efficacy of using dorsal root entry zone (DREZ) lesions to treat intractable pain caused by trauma to the conus medullaris and cauda equina. Traumatic lesions of this area are unique in that both the spinal cord and the peripheral nerve roots are injured. Although DREZ lesions have been shown to relieve pain of spinal cord origin in many patients, they have been shown not to relieve pain of peripheral nerve origin. Therefore, 39 patients with trauma to the conus medullaris and cauda equina who underwent DREZ lesioning for intractable pain were reviewed retrospectively.
The results of this review demonstrate the efficacy of DREZ lesions in these patients. At a mean follow-up period of 3.0 years, 54% of patients were pain-free without medications, and 20% required only nonnarcotic analgesic drugs for pain that no longer interfered with their daily activities. Better outcomes were noted in patients with an incomplete neurological deficit, with pain having an “electrical” character, and with injuries due to blunt trauma. Operative complications included weakness (four patients), bladder or sexual dysfunction (three), cerebrospinal fluid leak (two), and wound infection (two), but overall, 79.5% of patients (31 of 39) were without serious complications. Complications were limited to patients with prior tissue damage at the surgical exploration site and were most prevalent in patients who underwent bilateral DREZ lesions.
In conclusion, this preliminary report suggests that DREZ lesions may be useful in combating intractable pain from traumatic injuries to the conus medullaris and cauda equina, with some risk to neurological function that may be acceptable in this group of patients.