Regional intensity of neurosurgical care and integration of aneurysm coiling in the United States.

AIM: There is wide regional variability in the volume of procedures performed for similar surgical patients throughout the United States. We investigated the association of the intensity of neurosurgical care with the diffusion of the novel technology of cerebral aneurysm coiling. METHODS: We performed a retrospective cohort study involving patients who underwent any neurosurgical procedure from 2005-2010 and were registered in the National Inpatient Sample (NIS) database. A sub-cohort of patients undergoing aneurysm clipping or coiling was also created. Regression techniques were used to investigate the association of the average risk-adjusted intensity of neurosurgical care with the average rate of coiling. RESULTS: There were significant disparities in the rate of coiling among several states (ANOVA, P<0.0001). It ranged from 0.24 in Maryland, where clipping was very predominant, to 0.82 in Minnesota, where coiling was the main treatment modality used. In multivariate analysis, higher coiling rate was associated with increased age, higher income, rural hospital location, and small institution size. The Midwest was association with higher rate in comparison to the Northeast, whereas the West and the South had even lower rates. Increasing rate of coiling was associated with increasing intensity of neurosurgical care. There was a positive correlation of the average risk-adjusted intensity of neurosurgical care with the average rate of coiling per state (Pearson's ρ=0.43, P<0.001). CONCLUSION: We observed significant disparities in the rate of coiling in the United States. Increased intensity of neurosurgical care was positively associated with the integration of coiling in treatment of cerebral aneurysms.

Socioeconomic characteristics of patients undergoing ambulatory diagnostic cerebral angiography in four US States.

AIMS: Several groups have demonstrated the safety of ambulatory cerebral angiography, with no patients experiencing complications related to early discharge. Although this practice appears to be safe, the socioeconomic characteristics factoring in the selection of the patients have not been investigated. METHODS: We performed a retrospective cohort study involving 45,226 patients undergoing outpatient and 159,046 undergoing inpatient cerebral angiography, who were registered in the State Ambulatory Surgery Databases (SASD) and State Inpatient Databases (SID) respectively for 4 US States (New York, California, Florida, North Carolina). RESULTS: In a multivariate analysis of diagnostic cerebral angiography, Caucasian race (OR 1.36, 95% CI, 1.31, 1.42) and male gender (OR 1.36, 95% CI, 1.31, 1.41), were significantly associated with outpatient procedures. Higher Charlson Comorbidity Index (CCI) (OR 0.60, 95% CI, 0.54, 0.67), high income (OR 0.70, 95% CI, 0.67, 0.73), high volume hospitals (OR 0.69, 95% CI, 0.66, 0.73), and coverage by Medicare/Medicaid (OR 0.96, 95% CI, 0.92, 0.99) were associated with a decreased chance of outpatient procedures. Institutional charges were significantly less for outpatient cerebral angiography. The median charge for inpatient diagnostic cerebral angiography was $26,968 as compared to $16,151 in the outpatient setting (P < 0.0001, Student's t-test). CONCLUSION: Access to ambulatory diagnostic cerebral angiography appears to be more common for patients with private insurance and less comorbidities, in the setting of lower volume hospitals. Further investigation is needed in the direction of mapping these disparities in resource utilization.

Indications for treatment of recurrent carotid stenosis.

BACKGROUND: There is significant variation in the indications for intervention in patients with recurrent carotid artery stenosis. The aim of the present study was to describe these indications in a contemporary cohort of patients. METHODS: This was a systematic review of all peer-reviewed studies reporting on the indications for carotid intervention in patients with recurrent stenosis after carotid endarterectomy (CEA) or carotid artery stenting (CAS) that were published between 1990 and 2012. RESULTS: There were 50 studies reporting on a total of 3524 patients undergoing a carotid procedure; of these, 3478 underwent CEA as the initial intervention. Reintervention was by CEA in 2403 patients and by CAS in 1121. Only 54·7 per cent of the patients were treated for any symptoms and, importantly, just 444 (23·1 per cent of 1926 symptomatic patients) underwent intervention for documented ipsilateral symptoms. None of the studies reported whether the patients were evaluated for other sources of emboli. The remaining 45·3 per cent of patients had asymptomatic restenosis and in the majority of the studies were treated when the degree of stenosis exceeded 80 per cent. The time to repeat intervention was significantly longer in patients with recurrent atherosclerosis, in asymptomatic patients and in patients undergoing CEA. CONCLUSION: The reported criteria for retreatment of carotid stenosis were not rigorous and there is still significant ambiguity surrounding the indications for intervention.

Characterization of cuticular proteins in the red flour beetle, Tribolium castaneum.

We are characterizing the cuticular proteins of Tribolium castaneum (Herbst) (Coleoptera:Tenebrionidae) to determine their role in the function of the exoskeleton. Based on qualitative analyses of cuticles, we focused on the sodium dodecyl sulfate (SDS)-extractable proteins. A small-scale cuticle "mini-prep" procedure was devised that yields preparations virtually free of contaminating cellular material compared to hand-dissected preparations, as assessed by fluorescent microscopy using DAPI to stain nuclei. Proteins extracted in 1% SDS from various developmental stages (last larval instar, pupal, adult) were analyzed by one-dimensional denaturing polyacrylamide gel electrophoresis and by two-dimensional gel electrophoresis. The cuticular protein profiles show both similarities and differences among the stages examined. The amino acid composition, glycosylation, and partial amino acid sequence of several abundant cuticular proteins indicate similarity to cuticular proteins of other insects.