Biomedical subjects
Paul C McCormick
Publications and source records attributed to Paul C McCormick.
Clinical management of intramedullary spinal ependymomas in adults.
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Pathologic and epidemiologic findings of intramedullary spinal cord tumors.
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Cost-effectiveness of single-level anterior cervical discectomy and fusion for cervical spondylosis.
STUDY DESIGN: Cost-effectiveness analysis with retrospective cost analysis and literature review. OBJECTIVE: To determine the relative cost-effectiveness of anterior cervical discectomy and fusion (ACDF) with autograft, allograft, and allograft with plating for single-level anterior cervical spondylosis. SUMMARY OF BACKGROUND DATA: There are several accepted methods of surgically treating single-level cervical spondylosis anteriorly. No study has clearly demonstrated the superiority of one method over the alternatives. The techniques may differ in their operative risks and resource use, perioperative complications, short-term outcome, and long-term outcome and complications. Formal cost-effectiveness analysis (CEA) provides a structure for analyzing many variables and comparing different treatment outcomes. Sensitivity analysis is used to test the robustness of the model and to determine variables that have significant effects on the results. Future areas of research and refinements of the CEA model can be developed from these findings. METHODS: A retrospective review of hospital charges was performed for 78 patients who underwent single-level ACDF with allograft alone or ACDF with allograft and plating (ACDFP). The charges were converted to estimated costs for fiscal year 2000 using the ratio of costs to charges method. A CEA model was developed consisting of a decision-analysis model for the first year postsurgery and a Markov model for the next 4 years after surgery. Probabilities and outcome utilities were estimated from the literature. Outcome was measured in quality-adjusted life years (QALYs), and incremental CEA was performed. Several variables were tested in one-way sensitivity analysis. RESULTS: Compared with ACDF with autograft, ACDF with allograft offered an improvement in quality of life at a cost of 496 dollars per QALY. ACDFP provided additional gains in quality of life compared with ACDF with allograft at a cost of 32,560 dollars per QALY in the base case analysis. In sensitivity analysis, these estimates varied between 417 dollars and 741 dollars per QALY and between 19,090 dollars per QALY and domination of ACDFP by ACDF with allograft, respectively. The results were most sensitive to assumptions regarding differences in the length of the postoperative recovery period. CONCLUSIONS: ACDF with allograft offers a benefit relative to ACDF with autograft at a cost of 496 dollars per QALY. ACDFP has a benefit relative to ACDF with allograft at an approximate cost of 32,560 dollars per QALY. CEA provides a method for comparing the benefits and risks of these three procedures. Further research needs to be performed regarding these procedures, particularly examining the postoperative recovery period.
Intramedullary spinal cord tumors: molecular insights and surgical innovation.
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Wrong science: the SPORT trial and its potential impact on neurosurgery.
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National and regional rates and variation of cervical discectomy with and without anterior fusion, 1990-1999.
STUDY DESIGN: A national hospitalization database was used to determine rates and trends in the treatment of cervical disc disease. OBJECTIVE: To examine the temporal and geographic variations in hospitalizations and surgical procedures for cervical disc disease. SUMMARY OF BACKGROUND DATA: Studies of spinal surgery during the 1980s showed significant increases in the rates for all procedures, particularly those involving fusion. The management of cervical disc disease continues to be controversial. METHODS: Data from the National Hospital Discharge Survey from 1990 through 1999 were analyzed. Records were selected and categorized according to an algorithm of International Classification of Diseases (ICD-9) procedure and diagnosis codes. RESULTS: During the study period, the rate of hospitalization for surgical and nonsurgical treatment of cervical disc disease did not increase significantly. There was, however, a statistically significant increase in the proportion of hospitalizations for the surgical treatment of cervical disc disease that included a fusion procedure. There also was significant geographic variation in the rate of fusion procedures, with the South having the highest rate. CONCLUSIONS: Although the rate of surgery for cervical disc disease did not increase significantly during the 1990s, the rate of fusion procedures did rise significantly.
Midline ventral intradural schwannoma of the cervical spinal cord resected via anterior corpectomy with reconstruction: technical case report and review of the literature.
OBJECTIVE AND IMPORTANCE: Spinal cord schwannomas are intradural nerve sheath tumors that almost universally occupy a dorsolateral, lateral, or ventrolateral position. Therefore, resection of these lesions typically proceeds via a posterior or posterolateral approach. CLINICAL PRESENTATION: We present a case of a midline ventral intradural schwannoma of the cervical spinal cord causing myelopathy. To the best of our knowledge, no previous reports specifically discuss purely midline ventral intradural schwannomas. INTERVENTION: Resection of the tumor was performed via an anterior cervical corpectomy with spinal arthrodesis and fixation. We review possible causes for such an anomalous location for schwannoma as well as the advantages and disadvantages of various surgical strategies for removing the tumor. CONCLUSION: This case exemplifies the usefulness of anterior approaches to the cervical spine in treating unusual intradural spinal cord tumors.
Spine patient outcomes research trial.
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Outcomes research and lumbar discectomy.
Lumbar discectomy is generally performed to reduce pain or disability and thereby improve quality of life. Important surgery-related results, therefore, include the patients' perceptions of the effect of surgery on their health and ability to perform daily tasks. Spine surgeons should have an understanding of basic concepts of outcome measurement and be able to select appropriate questionnaires and incorporate them into their clinical practices and research. A brief review of the fundamental principles of outcome research is presented, and the recent lumbar discectomy literature concerning these ideas is summarized. Properly designed, conducted, and reported outcome studies of lumbar discectomy will assist the spine surgeon in selecting appropriate patients for surgery, educating them regarding expected results, and comparing this procedure with novel treatments for lumbar disc disease.
A controlled prospective study of neuropsychological dysfunction following carotid endarterectomy.
BACKGROUND: Although subtle cognitive injury as revealed by neuropsychological testing occurs in a substantial number of patients following carotid endarterectomy (CEA), there is controversy about whether this finding is a result of the surgery or the anesthesia. OBJECTIVES: To examine the changes in neuropsychological test performance in patients following CEA vs a control group of patients older than 60 years following spine surgery, so as to determine whether neuropsychological dysfunction after CEA is a result of surgery or anesthesia. METHODS: Patients undergoing CEA (n = 80) and lumbar spine surgery (n = 25) were assessed with a battery of neuropsychological tests preoperatively and on postoperative days 1 and 30. The neuropsychological performance of patients in the control group was used to normalize performance for patients in the CEA group, by calculating z scores using the mean and SD of the change scores in the control group. Significant cognitive dysfunction was defined as performance that exceeded 2 SDs above the mean performance of patients in the control group. RESULTS: Postoperative days 1 and 30 total deficit scores were significantly worse in the CEA group compared with the controls. When individual test results were examined, the CEA group performed significantly worse than the controls on the Rey Complex Figure test and Halstead-Reitan Trails B on day 1, and on the Rey Complex Figure on day 30. Overall, cognitive dysfunction was seen in 22 patients (28%) in the CEA group on day 1 and in 11 (23%) of 48 patients on day 30. CONCLUSIONS: Subtle cognitive decline following CEA occurs and persists for at least several weeks after surgery. This decline was absent in a control group.
Spinal cord and intradural-extraparenchymal spinal tumors: current best care practices and strategies.
The management of patients with intradural spinal tumors differs in many respects from approaches taken for patients with intracranial tumors. Intramedullary lesions are often completely surrounded by normal spinal cord, displacing vital functional tracts eccentrically. Extramedullary lesions can drastically compress the spinal cord and nerve roots, reducing normal tissue to a ribbon-like consistency. The small amount of normal tissue relative to tumor has implications for surgery and postoperative adjuvant therapy. In addition, operative intervention must take spinal stability into consideration. In this report, we describe the current best care practices and strategies for patients with a diagnosis of spinal astrocytoma, ependymoma, hemangioblastoma, schwannoma, and meningioma. Treatment of patients with intradural tumors of the spinal cord and adjoining structures has changed over the past 20 years. Advances in many disciplines including neuroradiology, neurosurgery, neurooncology, and neuropathology have contributed to expediting diagnosis and improving outcomes.