Biomedical subjects
Stephen J Haines
Publications and source records attributed to Stephen J Haines.
Teaching evidence-based medicine to surgical subspecialty residents.
BACKGROUND: Curricula for the teaching of evidence-based medicine to residents have been the subject of reports, analyses, and commentary. Specific programs for teaching evidence-based medicine principles to surgical subspecialty residents have not been identified by the authors. The objective of this article is to report our experience in establishing a teaching program in the principles of evidence-based medicine to surgical subspecialty residents. STUDY DESIGN: We established a teaching program in the principles of evidence-based medicine for neurosurgical residents in a busy neurosurgical training program. Two hours were set aside every other week, replacing traditional professors' rounds with sessions led jointly by a neurosurgeon and an epidemiologist, but based on case presentations from patients currently being treated. From these presentations, searchable clinical questions were developed, and the literature was searched, critically analyzed, and summarized. Results of several cycles on this process are reported. RESULTS: The group developed a repository of Internet-based resources for evidence-based education and practice. Using these resources, the group analyzed six topics in the first 2 years of the program. These included the "best" way to clinically grade patients after subarachnoid hemmorhage, considerations in the biopsy and treatment of enhancing intracerebral mass lesions in patients with acquired immunodeficiency syndrome, the use of prophylactic anticonvulsants in patients with primary brain tumors, the identification of cervical spine injuries in the emergency department, the grading of the fractures of the odontoid process, and the value of removing retained bullets from the spinal canal. The outcomes ranged from finding insufficient evidence to reach a conclusion, through the identification of well-conducted and well-reported critical syntheses of the topic already available in literature, to the development of the detailed algorithm for cervical spine clearance that was accepted by the institution's emergency department. CONCLUSIONS: By dedicating some specific time and using resources readily available in most academic health centers, it is possible to incorporate the teaching of the principles of evidence-based practice into the ongoing education of residents on a busy surgical subspecialty service.
Evidence-based neurosurgery.
OBJECTIVE: The evidence-based medicine movement is gaining influence in many medical specialties. Although many think that clinical medicine always has been based on evidence, the discipline of evidence-based medicine places particular emphasis on a defined set of principles of critical analysis of individual research reports, methodologically rigorous synthesis of multiple reports, and the collection and dissemination of evidence repositories that allow rapid application of evidence in practice. This article provides a selective introduction to the discipline of evidence-based medicine as it applies to neurological surgery. METHODS: The vast literature on evidence-based medicine has been reviewed selectively to identify resources that are readable, accessible, and relevant to neurosurgery. RESULTS: The history, concepts, and techniques of evidence-based medicine are presented in brief, and educational and methodological resources, as well as evidence repositories, are introduced. CONCLUSION: The techniques of evidence-based medicine are relevant to neurological surgery. There is a relatively large repository of critically analyzed and summarized evidence that is useful to the neurosurgical practitioner. Familiarity with these techniques and repositories can help the neurosurgeon bring the best available evidence to bear on the care of individual patients.
Rapid development of Chiari I malformation in an infant with Seckel syndrome and craniosynostosis. Case report and review of the literature.
To illustrate the rapidity with which a child can develop a severe, symptomatic Chiari I malformation, the authors present the case of a 3-month-old infant with Seckel syndrome (microcephaly, micrognathia, craniosynostosis, and multiple other abnormalities) and posterior sagittal and bilateral lambdoid synostosis. The infant underwent magnetic resonance (MR) imaging shortly after birth; the initial image demonstrated the cerebellar tonsils in the posterior fossa, with no herniation. He subsequently developed severe apneic episodes and bradycardia; repeated MR imaging at 3 months demonstrated severe tonsillar herniation with compression of the brainstem. The child underwent posterior fossa remodeling surgery, including release of the posterior sagittal and lambdoid sutures and decompression of the Chiari I malformation. The patient's apnea gradually improved; however, he died of complications of pneumonia and sepsis several weeks later. The authors identified from the literature 21 patients in whom there was a documented MR image or other neuroimage that did not reveal evidence of a Chiari I malformation, followed by a subsequent study with clear documentation of the presence of Chiari I malformation. The interval between the initial study and the development of the tonsillar herniation ranged from 11 days to 18.5 years. In most cases, a lumbar cerebrospinal fluid (CSF) diversion had been performed. This patient developed a severely symptomatic Chiari I malformation during a 3-month period. These reports illustrate that the Chiari I malformation can develop rapidly in the face of increased intracranial pressure, craniosynostosis, and spinal CSF diversion.
Moving targets and ghosts of the past: outcome measurement in brain tumour therapy.
Evaluation of novel therapies for brain tumours should logically consider quality and quantity of patient survival as primary endpoints. The urgency of the problem, however, frequently leads investigators to use surrogate endpoints and historical controls in order to more rapidly evaluate outcome. To examine the impact of the use of surrogate endpoints and historical controls on the evaluation of innovative brain tumour therapy, selective literature review of three content areas (intraarterial chemotherapy for malignant glioma, interstitial brachytherapy for malignant glioma and stereotactic radiosurgery for cerebral metastasis and malignant glioma) was carried out. The impact of surrogate outcome measures and use of historical controls was assessed by comparing the results of trials using these methods and randomised clinical trials. In the evaluation of both intraarterial chemotherapy and interstitial brachytherapy, promising results in early phase trials were not confirmed in randomised clinical trials. This result can be explained by selection bias and predicted by the use of controls carefully selected from large treatment data bases. In the evaluation of stereotactic radiosurgery, early phase trials are promising, but randomised clinical trials have not yet been done. Prior experience suggests that the early promising results with stereotactic radiosurgery should be subjected to randomised clinical trial validation before being considered proven. Careful selection of controls for early phase trials is necessary if erroneous conclusions are to be avoided.
Discectomy strategies for lumbar disc herniation: results of the LAPDOG trial.
Since its introduction in the 1970s percutaneous treatment of lumbar disc herniation has been an attractive concept that has been the object of technical development and clinical application throughout the world. Little scientific evaluation of the efficacy and effectiveness of the procedure has been done. To estimate the success rates of automated percutaneous and conventional discectomy in comparable patients and to document the resource consumption of patients treated in these ways, a multicenter randomized clinical trial designed to compare both treatment efficacy and cost-effectiveness of automated percutaneous discectomy and conventional discectomy in adult patients with no prior lumbar spinal surgery, no coexistent lumbar spinal disease, unilateral single level lumbar radiculopathy with images confirming disc herniation at the appropriate level. In the course of the trial important technical advances allowing epidural extraction of free-fragment disc herniation was incorporated into the trial. It was not possible to enroll the required number of patients to complete the trial. Of 5735 screened patients, 95 were eligible and 36 were enrolled. Two elected watchful waiting and did not have any surgical procedure. Eight patients were lost to follow-up. Among the 27 evaluable patients, 41% of the percutaneous discectomy patients and 40% of the conventional discectomy patients were assessed as achieving "success" on the primary outcome measure. No clinical trial of any percutaneous discectomy technique provides definitive evidence supporting the efficacy or effectiveness of the procedure. Such evidence should be required by patients to whom such procedures are proposed and those who are asked to pay for them.
Discectomy strategies for lumbar disc herniation: study design and implications for clinical research.
Although previous studies have found automated percutaneous discectomy and epidural percutaneous discectomy to be less efficacious than conventional discectomy, these percutaneous procedures may be effective and cost-effective as a first surgical treatment for herniated lumbar disc. Percutaneous procedures for herniated lumbar disc continue to be performed throughout the world without definitive evidence of efficacy or effectiveness. The objective of this article is to report the design considerations and final design of a study with the following objectives: (1) to estimate the efficacy of automated percutaneous and conventional discectomy in treating single level herniated lumbar discs in comparable patient populations, and (2) to test the hypothesis that the use of percutaneous discectomy as the first surgical procedure in such patients would result in less cost and fewer complications than utilizing conventional discectomy as the first procedure. A multicenter randomized clinical trial was designed that followed published eligibility criteria closely, allowed flexibility in timing of surgery (while collecting natural history information on patients identified before electing surgery), incorporated adjustments for newly developed technology and accommodated the unusual demands of assessing a procedure acknowledged to have inferior medical outcomes when compared to conventional therapy but which offered potential advantages in cost and safety. The study was successfully designed and funded. In its implementation we experienced several obstacles that may affect the success of other clinical trials. Despite using established eligibility criteria, our patient enrollment was lower than expected. Academic health centers and traditional research settings are seeing fewer patients who would be eligible for discectomy; private clinical centers are treating eligible patients but lack the incentives to participate in clinical research. Automated percutaneous discectomy and epidural percutaneous discectomy are widely performed procedures and, despite the aforementioned obstacles, their efficacy and cost-effectiveness need to be scientifically evaluated if we are committed to delivering appropriate patient care.