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D D Correa

Publications and source records attributed to D D Correa.

4 recordsLinked to original sources
PubMed2000

An integrated functional magnetic resonance imaging procedure for preoperative mapping of cortical areas associated with tactile, motor, language, and visual functions.

OBJECTIVE: To evaluate an integrated battery of preoperative functional magnetic resonance imaging (fMRI) tasks developed to identify cortical areas associated with tactile, motor, language, and visual functions. METHODS: Sensitivity of each task was determined by the probability that a targeted region was activated for both healthy volunteers (n = 63) and surgical patients with lesions in these critical areas (n = 125). Accuracy of each task was determined by the correspondence between the fMRI maps and intraoperative electrophysiological measurements, including somatosensory evoked potentials (n = 16), direct cortical stimulation (n = 9), and language mapping (n = 5), and by preoperative Wada tests (n = 13) and visual field examinations (n = 6). RESULTS: For healthy volunteers, the overall sensitivity was 100% for identification of the central sulcus, visual cortex, and putative Wernicke's area, and 93% for the putative Broca's area (dominant hemisphere). For patients with tumors affecting these regions of interest, task sensitivity was 97% for identification of the central sulcus, 100% for the visual cortex, 91% for the putative Wernicke's area, and 77% for the putative Broca's area. These sensitivities were enhanced by the use of multiple tasks to target related functions. Concordance of the fMRI maps and intraoperative electrophysiological measurements was observed whenever both techniques yielded maps and Wada and visual field examinations were consistent with fMRI results. CONCLUSION: This integrated fMRI task battery offers standardized and noninvasive preoperative maps of multiple critical functions to facilitate assessment of surgical risk, planning of surgical routes, and direction of conventional, intraoperative electrophysiological procedures. Thus, a greater range of structural and functional relationships is brought to bear in the service of optimal outcomes for neurosurgery.

Adolescent↗
PubMed1999

Concordance between functional magnetic resonance imaging and intraoperative language mapping.

Although the correspondence between functional-magnetic resonance imaging (fMRI) representations of the sensorimotor cortex and intraoperative electrophysiology (including somatosensory evoked potential, SSEP, recordings and direct cortical stimulation) has been reported, a similar correspondence between fMRI and intraoperative localization of the language-sensitive cortex is not as well established. The aim of the present study was to evaluate the concordance between fMRI and intraoperative electrophysiology with respect to the localization of the language-sensitive and sensorimotor cortices. We present the results of 21 patients who underwent language and sensorimotor mapping by fMRI and intraoperative electrophysiology including SSEP recordings (n = 21), direct cortical stimulation of motor cortex (n = 15) and direct cortical stimulation of Broca's and Wernicke's area (n = 5). When responses were obtained with both methods, localization of function concurred in all cases. These observations suggest that fMRI represents a reliable preoperative tool for the identification of language-sensitive areas.

Adolescent↗
PubMed1995

Bismuth subsalicylate toxicity as a cause of prolonged encephalopathy with myoclonus.

Bismuth subsalicylate preparations are over-the-counter products for gastrointestinal complaints. Bismuth toxicity causes delirium, psychosis, ataxia, myoclonus, and seizures and is reversible over several weeks or months, when bismuth intake is stopped. We report a 54-year-old man with a 6-week history of progressive confusion and memory difficulty and a 2-3-week history of involuntary movements and gait impairment. His encephalopathy was further characterized by marked multifocal myoclonic jerks, coarse postural tremors, postural instability, and gait ataxia. He gradually improved. Extensive toxic, metabolic, and infectious workup demonstrated bismuth toxicity. Spinal tap and brain magnetic resonance scan were normal. Electroencephalography showed bihemispheric slowing. As his encephalopathy cleared, he reported using bismuth subsalicylate long term (daily intake of 8 oz). Bismuth levels 5 weeks after cessation of bismuth were elevated and normalized after 12 weeks. He followed a typical course for bismuth toxicity with subacute progressive encephalopathy and gradual recovery. Creutzfeldt-Jakob was strongly considered due to his rapidly progressive encephalopathy, multifocal myoclonus, and ataxia. Due to its rarity, bismuth toxicity is often overlooked. We hope this presentation will increase recognition of bismuth toxicity. We believe more detailed labeling of bismuth products is needed to avoid similar toxicity from this readily available product.

Bismuth↗