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Biomedical subjects

R Cosgrove

Publications and source records attributed to R Cosgrove.

18 recordsLinked to original sources
PubMed2001

Economic assessment of rheolytic thrombectomy versus intracoronary urokinase for treatment of extensive intracoronary thrombus: Results from a randomized clinical trial.

BACKGROUND: Despite advances in mechanical and pharmacologic therapy, thrombus-containing lesions are at high risk for adverse events and remain a challenging subset for percutaneous coronary revascularization. Recently, rheolytic thrombectomy with the AngioJet device has been shown to safely remove intracoronary thrombus, but the overall cost-effectiveness of this technique is unknown. METHODS: We determined in-hospital and 1-year follow-up costs for 349 patients with overt intracoronary thrombus who were randomly assigned to treatment with intracoronary urokinase (6- to 30-hour infusion followed by definitive revascularization; n = 169) or immediate thrombectomy with the AngioJet device (n = 180) as part of the Vein Graft AngioJet Study (VeGAS) 2 trial. Catheterization laboratory costs were based on measured resource utilization and 1998 unit costs, whereas all other costs were estimated from hospital charges and cost center-specific cost-to-charge ratios. RESULTS: Compared with urokinase, rheolytic thrombectomy reduced the incidence of periprocedural myocardial infarction (12.8% vs 30.3%, P <.001) and major hemorrhagic complications (2.8% vs 11.2%, P <.001) and shortened length of stay by nearly 1 day (4.2 vs 4.9 days; P =.02). As a result, AngioJet treatment reduced procedural costs, hospital room/nursing costs, and ancillary costs with resulting hospital cost savings of approximately $3500 per patient during the initial hospitalization ($15,311 vs $18,841, P <.001). These cost savings were maintained at 1 year of follow-up ($24,389 vs $29,109, P <.001). CONCLUSIONS: Compared with standard treatment with intracoronary urokinase, rheolytic thrombectomy both improves clinical outcomes and reduces overall medical care costs for patients with extensive intracoronary thrombus.

Angioplasty, Balloon, Coronary↗
PubMed1997

Evidence for rapid face recognition from human scalp and intracranial electrodes.

It is still generally believed that complex visual analysis is not carried out within the first 100 ms. Here we show that intra- and extracranial visual evoked potentials (VEPs) differentiate previously seen faces from novel faces as early as 50 ms after stimulus onset. EEG was recorded from scalp electrodes in 12 male healthy volunteers (group I) and intracranially from implanted depth electrodes in the temporal and frontal cortex of seven epilepsy patients (group II). Both groups were engaged in a face recognition task. All subjects showed significant differential responses which occurred very early (50-90 ms) and later (190-600 ms). In group II, the early responses were recorded more frequently in the right hemisphere, whereas the late differential VEPs were found in both hemispheres. Both types of VEPs were more frequent in the temporal neocortex, underlining its role as a major contributor to these fast recognition processes.

Adult↗
PubMed1997

The archaeological attributes of behaviour: difference or variability?

Did the Neanderthals evolve into anatomically modern humans, or were they replaced by incoming populations of Homo sapiens sapiens? This is perhaps the most well-known question debated by palaeoanthropologists and archaeologists interested in the period from roughly 250,000 to 30,000 years ago in Eurasia. But while this debate may have attracted most of the media attention, there are other research questions that are at least as worthy of public interest as biological origins.

Animals↗
PubMed1997

Neurophysiologic correlates of implicit face memory in intracranial visual evoked potentials.

Visual evoked potentials were recorded in the amygdala, hippocampus, mid- and inferotemporal cortex, orbitofrontal cortex, and lateral frontal cortex of seven epileptic patients while they were engaged in a difficult task requiring the discrimination between repeated and nonrepeated faces. The explicit recognition of previously seen faces was at chance levels, as measured by the accuracy of push-button responses. Nevertheless, all subjects showed clear-cut differential evoked responses to repeated versus nonrepeated faces, indicating implicit encoding of the distinction between the two types of stimuli. Differential responses were more frequent in neocortical recording sites (especially in the mid- and inferotemporal leads) than in limbic recording sites such as the amygdala and hippocampus. The authors conclude that implicit encoding processes are modulated by neocortical visual association areas of the temporal lobes.

Adult↗
PubMed1995

Cingulotomy for intractable obsessive-compulsive disorder. Prospective long-term follow-up of 18 patients.

BACKGROUND: The purpose of this study was to assess prospectively long-term change in obsessive-compulsive disorder (OCD) symptoms in patients with an OCD diagnosis that was confirmed by structured interview and with documented unsuccessful trials of multiple medications and attempts at behavior therapy. METHODS: We conducted an unblinded preoperative and follow-up assessment of comorbid diagnosis; OCD, depressive, and anxiety symptoms; and functional status in 18 patients who underwent cingulotomy. RESULTS: At a mean follow-up of 26.8 months, five patients (28%) met conservative criteria for treatment responders, and three others (17%) were partial responders. The group improved significantly in mean functional status, and few serious adverse events were found. Improvement in OCD symptoms was strongly correlated with improvement in depressive and anxiety symptoms. CONCLUSIONS: The rate of clinical improvement was consistent with a previous retrospective study in the same setting, indicating that 25% to 30% of the patients who previously were unresponsive to medication and behavioral treatments are significantly improved after cingulotomy. Cingulotomy remains a last resort treatment for severely incapacitated patients who have not responded to all other state-of-the-art pharmacological and behavioral treatments for OCD and is not to be taken lightly.

Adult↗
PubMed1995

Selectively distributed processing of visual object recognition in the temporal and frontal lobes of the human brain.

Evoked potentials to visually driven cognitive tasks were recorded through depth electrodes placed bilaterally within the amygdala, hippocampus, midtemporal and inferotemporal cortex, and lateral frontal cortex of 6 epileptic patients. Task-related differential response patterns were used to identify the recording sites engaged by specific aspects of visual encoding. In this group of 6 patients, the amygdala was most frequently engaged in encoding the familiarity of faces; midtemporal and inferotemporal cortex, in encoding perceptual identity and object categorization; and lateral frontal cortex, in holding visual object information in working memory. The two aspects of encoding that most frequently engaged the hippocampal region were related to working memory and object categorization. The processing of complex visual knowledge is thus anatomically distributed but regionally specialized. These experiments also showed that identical input and output parameters can engage different areas of the brain depending on the nature of the instructional set.

Adult↗
PubMed1993

Differential neural activity in the human temporal lobe evoked by faces of family members and friends.

In 6 patients, depth electrodes revealed differential evoked responses to familiar versus novel faces. These differential responses were obtained in the amygdala, hippocampus, and temporal neocortex but not in the dorsolateral frontal or cingulate cortex. The limbic and temporal structures that differentiated novel from familiar faces did not respond differentially to variations in luminance. Limbic structures and temporal cortex thus appear to participate in face recognition and in encoding the familiarity of visual experiences.

Adult↗
PubMed1991

Immunocytochemical demonstration of axonal and perikaryal acetylcholinesterase in human cerebral cortex.

The adult human neocortex contains a dense net of axons and perikarya which yield an acetylcholinesterase-rich enzymatic reaction pattern in histochemical experiments. We employed a monoclonal antibody to human acetylcholinesterase and a method for the concurrent visualization of histochemical and immunohistochemical reaction-products to explore the relationship between immunological and enzymatic markers of acetylcholinesterase. We observed that the cortical axons and perikarya with a histochemically determined acetylcholinesterase-rich enzymatic activity also contain acetylcholinesterase-like immunoreactivity. This was especially informative for the intracortical acetylcholinesterase-rich perikarya of layers III and V since these neurons require prolonged incubations for histochemical detection and since they are not conspicuous in other animal species. The availability of a reliable immunohistochemical method makes it possible to investigate the distribution of the acetylcholinesterase enzyme molecule independent of its enzymatic activity.

Acetylcholinesterase↗
PubMed1989

The measurement of toothbrush wear.

Toothbrushes wear out and progressively lose their ability to clean as the bristles abrade and become curled and matted. To study the factors that influence this process, we developed a quantitative measure of bristle splaying (wear index) and a method for judging and ranking the overall state of brush deterioration (wear rating) and used these to determine the effects of the individual user, brush design, time in use, and bristle material. Wear index is the average increase in brush-head dimensions normalized for maximum bristle length, and is dimensionless. Wear rating is a subjective means of classifying the increasing severity of deterioration on a scale of 0 to 3. The wear characteristics of a variety of commercial and experimental brushes with different design features were determined. Test variables were time in use, brush design (e.g., geometry and size of the brush head), and bristle composition. Time of use, the individual user, and bristle composition were found to have the strongest influences on splaying, and brush design was found to have the least influence. The wear index offers a quantitative means of comparing brushes of different dimensions at various stages of splaying. The wear rating, although qualitative, is a quick means of ranking brushes in various stages of deterioration. The two methods correlate (R2 = 0.87), and both are sensitive to several factors that affect brush durability. Therefore, these methods appear to be suitable not only for research, but also for quality control, the setting of standards, and for substantiation of advertising claims.

Adult↗
PubMed1988

Cavernous hemangiomas of the spinal cord: MR imaging.

In three patients with histologically proved cavernous hemangiomas of the spinal cord, magnetic resonance (MR) imaging was superior to myelography, delayed computed tomography (CT) myelography, and contrast-enhanced CT in depicting the lesion. The presence of mixed subacute and chronic hemorrhage, suggested by mixed high- and low-signal-intensity components of these lesions on MR images, may be characteristic of this rare, intramedullary vascular malformation.

Adult↗
PubMed1987

CT findings in late-onset epilepsy.

We reviewed the CT findings of 387 patients with new-onset seizures after the age of 50. Seizures were generalized in 212 patients, focal in 160, and indeterminant in 15. CT scanning revealed cerebral atrophy in 113 cases, ischemic lesions in 75, cerebral neoplasms in 20, and no abnormality in 177 cases. Tumours were found in only three patients with generalized seizures, and all three had focal neurological deficits at the time of CT diagnosis, while 17 neoplasms were discovered in patients with a focal seizure disorder. The majority of patients with late-onset epilepsy have a normal CT scan with cerebral atrophy being the most common abnormality detected. Cerebral vascular disease appears to be the most frequently identified cause of late-onset epilepsy, while cerebral neoplasms are uncommon.

Age Factors↗
PubMed1986

Embolization with temporary balloon occlusion of the internal carotid or vertebral arteries.

Functional vascular anastomoses at the base of the brain allow for temporary occlusion of the carotid or vertebral arteries. Six embolizations with temporary balloon occlusion of the internal carotid or vertebral artery are reported. Polyvinyl alcohol was the embolic material in all cases and all procedures were performed using digital angiography. The size of the embolic particles and the positioning of the balloon related to the branches of the occluded vessel is discussed.

Adolescent↗
PubMed1986

Spinal arteriovenous malformations: advances in therapeutic embolization.

Five patients with spinal arteriovenous malformations (AVMs) supplied at least in part by the anterior spinal artery were treated by embolization. Complete occlusion of the malformations was obtained without complication in all patients. Improved endovascular treatment of spinal AVMs is now possible with the use of calibrated particles of polyvinyl alcohol, serial digital subtraction angiography, and temporary balloon occlusion of the vertebral artery in cervical AVMs supplied by a pedicle arising from the vertebral artery.

Angiography↗
PubMed1984

The transfer of cephradine across the placenta.

The transfer of maternally administered cephradine (1 g given intravenously) to the fetal circulation and amniotic fluid was investigated in 2 pregnant patients undergoing fetoscopy. Cephradine was detected in fetal serum between 23 and 72 minutes after injection and was present in therapeutic concentrations. Fetal serum levels appeared to peak at approximately 40-50 min. Amniotic fluid levels were rising during the sampling period of 97 min. Cephradine is transferred across the placenta and appears to be a suitable antibiotic for use in selected obstetric patients when penetration of the fetal compartment is desirable.

Amniotic Fluid↗