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Purpose: The impact of cardiology fellows (CFs) and interventional cardiology fellows (ICFs) on patient radiation and contrast exposure during diagnostic coronary angiography and percutaneous coronary intervention is unknown. Methods: Between 2011 and 2014, 16,175 cases were retrospectively assessed involving 27 CFs, 22 ICFs and 24 staff as primary operators. Results: During diagnostic coronary angiography, ICFs administered the lowest radiation dose (5,648±5,523 cGy*cm2; 1.30 ± 1.27 mSv)—achieving 22% less radiation than the staff (6,889±4,294 cGy*cm2; 1.58 ± 0.99 mSv) and 36% less than CFs (7,700±6,751 cGy*cm2; 1.77 ± 1.55 mSv) (p

Background Glaucoma surgical management has evolved significantly with the introduction of minimally invasive glaucoma surgery. Our aim was to evaluate trends in Canadian glaucoma surgery billing code usage as a surrogate index of the current impact of this new technology in Canada's publicly funded health-care system. Methods Retrospective administrative health records analysis of all patients who underwent a publicly funded glaucoma filtration procedure from January 2003 to December 2016 in the 6 largest Canadian provinces. The frequency of glaucoma-related procedures was adjusted against primary open-angle glaucoma prevalence data. Frequency of all glaucoma filtration procedures with and without implantation of a drainage device in each province per year is reported. Results Nationwide, glaucoma filtration procedures per 1000 primary open-angle glaucoma patients per year remained constant, with increased drainage device implantation over time (P

PURPOSE: To describe a case of unilateral isolated traumatic posterior corneal ectasia characterized by advanced multi-modal diagnostic tests. METHODS: Case report and literature review. RESULTS: Following blunt trauma to the left eye, a 34-year-old woman presented with persistently blurry vision. Central corneal thickness was 300 µm, compared to 519 µm in the right eye. Scheimpflug tomography revealed significant corneal thinning in a defined inferotemporal region with corresponding elevation of the posterior corneal surface. Posterior corneal ectasia was confirmed with anterior segment optical coherence tomography. Wavefront aberrometry demonstrated increased higher order aberrations in the affected eye. Vision remained stable during 4.5 years of follow-up with a final visual acuity of 20/50 maintained with spectacle correction only. CONCLUSIONS: A unique case of unilateral post-traumatic posterior corneal ectasia was presented. The multi-modal imaging provided a detailed characterization of the structural characteristics of the cornea, guided management, and allowed for differentiation from other corneal pathologies at an early stage. [ Journal of Refractive Surgery Case Reports . 2021;1(2):e31–e35.]

To quantify changes in optical coherence tomography angiography (OCTA) parameters following intravitreal anti-vascular endothelial growth factor treatment for diabetic macular edema (DME), and to assess associations between pretreatment OCTA parameters and visual outcomes.Prospective cohort study.Twenty-nine patients with DME received 5 monthly intravitreal injections of aflibercept. OCTA data obtained at baseline and at 6 months were compared using the Wilcoxon signed-rank test. OCTA parameters were foveal avascular zone (FAZ) area, FAZ perimeter, FAZ circularity, vessel density in the superficial vascular plexus (segmented into central, inner, outer, and full Early Treatment of Diabetic Retinopathy Study [ETDRS] map regions. Subanalysis divided patients into treatment responders (reduction of central subfield thickness50 µm over treatment) and nonresponders. Associations between pretreatment OCTA parameters and visual acuity outcomes were analyzed using multivariable linear and logistic regression.A total of 29 patients were included: 25 patients (86.2%) had nonproliferative diabetic retinopathy, and 4 patients (13.8%) had proliferative diabetic retinopathy. Vessel density was reduced in the central (p = 0.004) and inner (p = 0.013) ETDRS map regions. This effect was significant only among treatment responders (central p = 0.002; inner p = 0.017). Pretreatment OCT and OCTA parameters were not associated with final visual acuity outcomes.Following intravitreal aflibercept treatment for DME, there was a significant decrease in vessel density of the superficial vascular plexus at the central and inner ETDRS map regions. This was seen only among treatment responders. Observations here are likely to represent the limits of OCTA technology itself, where pretreatment vessel density may have been artifactually overestimated by suspended scattering particles in motion. Pretreatment OCTA parameters did not serve as biomarkers for visual outcome following anti-vascular endothelial growth factor therapy.

To identify factors associated with secondary surgical intervention after glaucoma filtration surgery.Population-based retrospective cohort.Patient records with billing claims for a primary glaucoma filtration surgery occurring between April 2003 and March 2015 were identified. Each identified record was examined for instances of secondary glaucoma surgeries within the patient's first postoperative year. Baseline characteristics of patients who required secondary surgical intervention were compared with those who did not. A multivariable Cox proportional hazards model was used to calculate hazard ratios.Within a cohort of 10,097 patients, 349 (3.46%) underwent a secondary surgical intervention within the first postoperative year. Interventions were less frequent after surgeries that included an indwelling drainage device (HR=0.58 95% CI, 0.37-0.89), phacoemulsification (HR=0.33, 0.21-0.52), or both (HR=0.09, 0.03-0.31). Patients with preoperative aminoglycoside and mydriatic exposure had significantly increased risk of secondary surgical intervention (HR=3.19, 1.89-5.36) and (HR=2.32, 1.49-3.61). Patients who underwent surgery on their contralateral eye experienced secondary surgical interventions more frequently: 7.44 per 10,000 person-days (versus 1.18 per 10,000 person-days, p0.0001). No significant differences in the rates of secondary surgical intervention were observed for patients taking different classes of glaucoma medications or those exposed to higher amounts of benzalkonium chloride.In Ontario, the overall rates of secondary surgical interventions in the first postoperative year are low but significantly higher in certain patient populations. Further work is required to address the higher rate of secondary surgical intervention in patients with a history of certain perioperative eye drop medications and those who require sequential-bilateral procedures.

Purpose To develop and validate neural network (NN) vs logistic regression (LR) diagnostic prediction models in patients with suspected giant cell arteritis (GCA). Design: Multicenter retrospective chart review. Methods An audit of consecutive patients undergoing temporal artery biopsy (TABx) for suspected GCA was conducted at 14 international medical centers. The outcome variable was biopsy-proven GCA. The predictor variables were age, gender, headache, clinical temporal artery abnormality, jaw claudication, vision loss, diplopia, erythrocyte sedimentation rate, C-reactive protein, and platelet level. The data were divided into three groups to train, validate, and test the models. The NN model with the lowest false-negative rate was chosen. Internal and external validations were performed. Results Of 1,833 patients who underwent TABx, there was complete information on 1,201 patients, 300 (25%) of whom had a positive TABx. On multivariable LR age, platelets, jaw claudication, vision loss, log C-reactive protein, log erythrocyte sedimentation rate, headache, and clinical temporal artery abnormality were statistically significant predictors of a positive TABx (P≤0.05). The area under the receiver operating characteristic curve/Hosmer-Lemeshow P for LR was 0.867 (95% CI, 0.794, 0.917)/0.119 vs NN 0.860 (95% CI, 0.786, 0.911)/0.805, with no statistically significant difference of the area under the curves (P=0.316). The misclassification rate/false-negative rate of LR was 20.6%/47.5% vs 18.1%/30.5% for NN. Missing data analysis did not change the results. Conclusion Statistical models can aid in the triage of patients with suspected GCA. Misclassification remains a concern, but cutoff values for 95% and 99% sensitivities are provided (https://goo.gl/THCnuU).

Introduction Late open surgical conversion following endovascular aneurysm repair (EVAR) may occur more frequently after performing EVAR in anatomy outside the instructions for use (IFU). This study reviews predictors and outcomes of late open surgical conversion for failed EVAR. Methods This retrospective cohort study reviewed all EVARs performed at the Ottawa Hospital between January 1999 and May 2015. Open surgical conversions >1 month post EVAR were identified. Variables analysed included indication for conversion, pre-intervention AAA anatomy, endovascular device and configuration, operative technique, re-interventions, complications, and death. Results Of 1060 consecutive EVARs performed, 16 required late open surgical conversion. Endografts implanted were Medtronic Talent (n = 8, 50.0%), Medtronic Endurant (n = 3, 18.8%), Cook Zenith (n = 4, 25.0%), and Terumo Anaconda (n = 1, 6.2%). Eleven grafts were bifurcated (68.8%), five were aorto-uni-iliac (31.2%). The median time to open surgical conversion was 3.1 (IQR 1.0–5.2) years. There was no significant difference in pre-EVAR rupture status (1.4% elective, 2.1% ruptured, p = .54). Indications for conversion included: Type 1 endoleak with sac expansion (n = 4, 25.0%), Type 2 endoleak with expansion (n = 2, 12.5%), migration (n = 3, 18.8%), sac expansion without endoleak (n = 2, 12.5%), graft infection (n = 3, 18.8%), rupture (n = 2, 12.5%). Nine patients (56.2%) underwent stent graft explantation with in situ surgical graft reconstruction, seven had endograft preserving open surgical intervention. The 30 day mortality was 18.8% (n = 3, all of whom having had endograft preservation). Ten patients (62.5%) suffered major in hospital complications. One patient (6.5%) required post-conversion major surgical re-intervention. IFU adherence during initial EVAR was 43.8%, versus 79.0% (p Conclusions Open surgical conversion following EVAR results in significant morbidity and mortality. IFU adherence of EVARs later requiring open surgical conversion is markedly low. More data are required to elucidate the impact of increasing liberalisation of EVAR outside of IFU.

Temporal artery biopsy (TAB) is the gold standard for confirming the diagnosis of giant cell arteritis (GCA) when positive. However, the clinical significance of healed/healing (HH) arterial injury on TAB is not well understood. The purpose of this study was to evaluate the clinical significance of this finding on TAB by determining its association with seromarkers typically predictive of GCA.Single-centre, retrospective, investigational cohort study.A total of 385 consecutive TABs for clinical suspicion of GCA between January 2009 and January 2016.Elevations in erythrocyte sedimentation rate, C-reactive protein, and platelet count were compared between patients with negative TAB, GCA-positive TAB, and HH arterial injury using statistical trend testing. Odds ratios of seromarker elevations for HH arterial injury versus GCA were calculated.Seventy-six GCA-positive, 69 HH, and 240 negative TABs were identified. Mantel-Haenszel tests of trend indicated that platelets400 000/µL (p0.01), erythrocyte sedimentation rate ≥50 mm/hr (p0.01), and C-reactive protein ≥24.5 mg/L (p0.01) occurred with intermediate frequency in the HH TAB group. The odds of HH TAB were 3.6 times greater (95% CI 1.5-8.5) with platelets400 000/µL.HH arterial injury is a heterogenous group that requires treatment in the appropriate clinical setting. From our study, we found that the HH group is intermediate between GCA-positive and GCA-negative biopsy with respect to serology markers only. Thrombocytosis is an independent predictor of HH TAB. With further studies, this marker may be considered when making treatment decisions. Further studies are required to better understand this entity.

Background. Implantation of sutureless, scleral-fixated posterior chamber intraocular lenses (SSFIOL) is a promising option in the surgical management of patients unable to undergo standard cataract surgery due to insufficient capsular support. The purpose of this study was to describe the indications, visual outcomes and complications of SSFIOL implantation.Methods. Retrospective, investigational cohort study of 112 consecutive SSFIOL implantations between July 2013 and August 2017. Pre-operative ocular morbidity, operative indications, postoperative outcomes, complications, and reinterventions were summarized. Visual and refractive outcomes were compared between the pre- and latest postoperative visit using Wilcoxon signed-ranked test.Results. Mean follow-up: 13.0 ± 10.4 months. Primary surgical indication was dislocated IOL due to zonular weakness (77 eyes (68.8%)). At latest follow-up, there was improvement in uncorrected visual acuity (1.3 ± 0.8 to 0.64 ± 0.60 logMAR, p 30 mmHg (26.8%), cystoid macular edema (CME) (14.3%), transient hypotony (13.4%), iris capture (12.5%), uveitis-glaucoma-hyphema (UGH) syndrome (11.6%), vitreous hemorrhage (VH) (6.3%). Operative reinterventions included SSFIOL exchange (3.6%), SSFIOL repositioning (5.4%), SSFIOL removal (2.7%). Ten (8.9%) patients required multiple re-interventions.Conclusion. SSFIOL implantation is a reasonable option for eyes with inadequate capsular support, resulting in visual improvement in most patients. Many of the surgical complications were related to a floppy iris-lens diaphragm (UGH syndrome, iris capture), which were predisposed in eyes with complex pathology. Surgical modifications can be made to minimize the iris-related complications.

Although the absence of aneurysm-related mortality, postimplantation rupture, and reintervention after endovascular aneurysm repair (EVAR) is desirable, it may not necessarily reflect successful aneurysm sac exclusion. Sac regression may be a more sensitive marker for EVAR success and may be influenced by factors beyond the presence or absence of an endoleak. The objective of this study is to determine the rate of overall long-term sac regression after EVAR and the influence of nonanatomic factors, and endograft devices used at our center.This retrospective cohort study included all EVARs performed for intact and ruptured abdominal aortic aneurysms (AAAs) at a university teaching hospital. Preoperative, operative, and follow-up data were collected using clinical and radiologic institutional databases. Preoperative and post-EVAR sac diameters were determined by a blinded observer in accordance with Society for Vascular Surgery guidelines. Absolute and relative sac regression was determined at the following intervals: 0 to 6 months, 6 to 12 months, 12 to 18 months, 18 months to 2 years, 2 to 5 years, 5 to 10 years, and more than 10 years.From 1999 to 2015, 1060 patients underwent EVAR for an AAA at the Ottawa Hospital. Procedures were performed using a total of nine unique endograft devices, with five devices (Cook Zenith, n = 398; Medtronic Endurant, n = 375; Medtronic Talent, n = 183; Cook Zenith LP, n = 52; and Terumo Anaconda, n = 23) used in 97% of the procedures. The mean preoperative AAA diameter was 61.2 mm, with no detectable differences between endograft devices with respect to age, preoperative AAA diameter, or rupture diagnosis. Overall mean sac regression increased from -1.3 mm at 6 months, to -14.9 mm beyond 10 years. The majority of sac regression was achieved within 2 years. Only 90 of the 1060 patients (8.5%) experienced sac expansion of greater than 5 mm at some point during their follow-up period. Kaplan-Meier analyses revealed statistically significant device-specific variability in sac regression rates, even in the absence of an endoleak. Cox proportional hazard modeling demonstrated that age less than 75 years (hazard ratio [HR], 1.4; P = .001), female sex (HR, 1.4; P = .003), absence of type I endoleak (HR, 4.6; P .0001), AAA greater than 70 mm (HR, 1.6; P .0001), and both the Zenith (HR, 2.0; P .0001) and Endurant (HR, 1.7; P = .001) devices were associated with shorter time to more than 5 mm sac regression.This study demonstrated a pattern of sac diameter change after EVAR, with the majority of sac regression occurring within the first 2 years. Variability in sac regression was influenced by nonanatomic variables including age, sex, original AAA diameter, and specific endograft device, even after controlling for the presence or absence of an endoleak. The biophysical relationship between specific endograft design and materials, and sac regression is yet to be determined.

The impact of adopting new single photon emission computed tomography (SPECT) cameras and new reconstruction algorithms on left ventricular (LV) volumes has not been well established. We sought to understand the impact of hardware and software changes on normal LV reference ranges.Consecutive patients who underwent stress Tc-99m tetrofosmin 8-frame gated SPECT MPI were screened. Patients with a history of myocardial infarction, coronary revascularization, abnormal MPI, or known LV dysfunction/reduced ejection fraction were excluded. A total of 1953 consecutive normal patients, with rest LV end-diastolic volume (EDV) and end-systolic volume (ESV) measurements were analyzed. After stratifying according to sex, LV volumes indexed to body surface area were compared across the different gamma cameras.In a normal population, measurements with CZT were different from those obtained by the dual-headed NaI gamma cameras for LV EDVi (men: 53.6 ± 10.4 vs 48.3 ± 10.2 mL/m(2) and women: 43.3 ± 8.9 vs 37.8 ± 9.3 mL/m(2); P 0.001) and LV ESVi (men: 21.7 ± 7.0 vs 16.9 ± 6.2 mL/m(2) and women: 13.4 ± 5.3 vs 10.6 ± 4.7 mL/m(2); P 0.001). Inter- and intra-observer reliability for all measures was excellent. These findings were verified in a prospectively collected cohort. A sub-analysis of LV measurements comparing new resolution recovery and standard reconstruction software revealed no significant differences in LV measures.This study demonstrates that normal references ranges of LV volumes vary between SPECT cameras and confirms the need for establishing reference values that are camera specific.

To determine whether differences between eyes in axial length (AL) and corneal power (K) on optical biometry are predictive of refractive outcomes.Retrospective cohort study.A total of 729 patients (1458 eyes) who underwent bilateral phacoemulsification at TLC (Mississauga, Ontario, Canada) from September 2013 to August 2015.We compared the proportion of patients having0.5 diopters (D) of refractive error from target stratified by interocular axial length differences (IALDs) and interocular K differences (IKDs) between eyes as measured by optical biometry (IOL-Master, Carl Zeiss Meditec, Oberkochen, Germany). Analysis was repeated for 0.25 D or 1.0 D targets and for patients with uncorrected visual acuity (UCVA)0.3 logarithm of the minimum angle of resolution (logMAR) postoperatively.Proportions, odds ratios (ORs), and corresponding 95% confidence intervals (CIs) were computed using generalized estimating equations to account for within-patient correlation.Some 79.1% of eyes were ≤0.5 D of refractive target, 47.0% were ≤0.25 D, and 97.2% were ≤1.0 D. The OR of having a refractive outcome0.5 D from target for IALD cutoff of 0.2 mm was 1.4 (1.1-1.8), of 0.3 mm was 1.6 (1.2-2.1), and of 0.4 mm was 1.8 (1.3-2.5). This translates to 70.0% (63.5-75.7) within target for IALD of ≥0.4 mm versus 80.7% (78.4-82.9) for0.4 mm. For a given patient with IALD, the chance of being off target was similar for the shorter and longer eye. Eyes outside of target were twice as likely to be-0.5 D than0.5 D. Interocular K difference was largely not associated with prediction error, yet larger IKD-flat, steep, and average were associated with increased odds of UCVA0.3 logMAR postoperatively.Interocular axial length difference of as little as ≥0.2 mm is associated with a higher chance of0.5 D of refractive error from target and worse UCVA. Interocular K difference was not associated with worse refractive error from target, although a difference of ≥0.4 D was associated with worse UCVA. These cutoffs should be considered in preoperative planning and discussion with patients. Future study is required to assess whether repeating measurements, using adjunctive measurement devices, or attempting to separate true differences from artifact based on preoperative refractive characteristics reduces residual refractive error.

Prognostic value of positron emission tomography (PET) myocardial perfusion imaging (MPI) is well established. There is paucity of data on how the prognostic value of PET relates to the hemodynamic response to vasodilator stress. We hypothesize that inadequate hemodynamic response will affect the prognostic value of PET MPI. Using a multicenter rubidium (Rb)-82 PET registry, 3406 patients who underwent a clinically indicated rest/stress PET MPI with a vasodilator agent were analyzed. Patients were categorized as, “responders” [increase in heart rate ≥ 10 beats per minute (bpm) and decrease in systolic blood pressure (SBP) ≥10 mmHg], “partial responders” (either a change in HR or SBP), and “non-responders” (no change in HR or SBP). Primary outcome was all-cause death (ACD), and secondary outcome was cardiac death (CD). Ischemic burden was measured using summed stress score (SSS) and % left ventricular (LV) ischemia. After a median follow-up of 1.68 years (interquartile range = 1.17- 2.55), there were 7.9% (n = 270) ACD and 2.6% (n = 54) CD. Responders with a normal PET MPI had an annualized event rate (AER) of 1.22% (SSS of 0–3) and 1.58% (% LV ischemia = 0). Partial and non-responders had higher AER with worsening levels of ischemic burden. In the presence of severe SSS ≥12 and LV ischemia of ≥10%, partial responders had an AER of 10.79% and 10.36%, compared to non-responders with an AER of 19.4% and 12.43%, respectively. Patient classification was improved when SSS was added to a model containing clinical variables (NRI: 42%, p

Objective Endovascular aneurysm repair for ruptured abdominal aortic aneurysm is being increasingly applied as the intervention of choice. The purpose of this study was to determine whether survival and reintervention rates after ruptured abdominal aortic aneurysm vary between endograft devices. Methods This cohort study identified all ruptured abdominal aortic aneurysms performed at The Ottawa Hospital from January 1999 to May 2015. Data collected included patient demographics, stability index at presentation, adherence to device instructions for use, endoleaks, reinterventions, and mortality. Kruskal–Wallis test was used to compare outcomes between groups. Mortality outcomes were assessed using Kaplan–Meier survival analysis, and multivariate Cox regression modeling. Results One thousand sixty endovascular aneurysm repairs were performed using nine unique devices. Ninety-six ruptured abdominal aortic aneurysms were performed using three devices: Cook Zenith ( n = 46), Medtronic Endurant ( n = 33), and Medtronic Talent ( n = 17). The percent of patients presented in unstable or extremis condition was 30.2, which did not differ between devices. Overall 30-day mortality was 18.8%, and was not statistically different between devices ( p = 0.16), although Medtronic Talent had markedly higher mortality (35.3%) than Cook Zenith (15.2%) and Medtronic Endurant (15.2%). AUI configuration was associated with increased 30-day mortality (33.3% vs. 12.1%, p = 0.02). Long-term mortality and graft-related reintervention rates at 30 days and 5 years were similar between devices. Instructions for use adherence was similar across devices, but differed between the ruptured abdominal aortic aneurysm and elective endovascular aneurysm repair cohorts (47.7% vs. 79.0%, p 30 days post-endovascular aneurysm repair ( p = 0.01). Type 1 endoleak rates differed significantly across devices (Cook Zenith 0.0%, Medtronic Endurant 18.2%, Medtronic Talent 17.6%, p = 0.01). Conclusion Although we identified device-related differences in endoleak rates, there were no significant differences in reintervention rates or mortality outcomes. Favorable outcomes of Cook Zenith and Medtronic Endurant over Medtronic Talent reflect advances in endograft technology and improvements in operator experience over time. Results support selection of endograft by operator preference for ruptured abdominal aortic aneurysm.

A 27-year-old woman presented to her family doctor with bilateral ocular pain that waxed and waned, redness and photophobia. The symptoms had progressed over several months and were followed by hoarseness and dyspnea, all of which interfered with her activities of daily living. The patient’s

Introduction Aortic valve calcification (AVC) has been associated with major adverse cardiovascular events and all-cause mortality. We sought to develop and validate a method to quantify AVC using coronary CT angiography (CTA). Methods Of 59 patients who underwent both non-contrast and contrast enhanced coronary CTA, 25 patients served as the derivation cohort and 34 patients served as the validation cohort. For non-contrast enhanced CT, quantification of AVC was performed using the Agatston method for coronary artery calcification (CAC). For contrast enhanced coronary CTA, a region of interest (ROI) was placed in the ascending aorta and the mean aortic attenuation value (HU Aorta ) and standard deviation (SD) were measured. Using a calcium threshold of mean HU Aorta + 2SD, the AVC CTA was calculated. All other Agatston score parameters (weighting factors and area calculations) remained unchanged. Results In the derivation cohort, the correlation between AVC CAC and AVC CTA was excellent (r = 0.982). Using the line of best fit, a correction factor was calculated enabling the conversion of AVC CTA results to a AVC CAC equivalent (AVC Corrected = 1.868 × AVC CTA ). Using this correction in the validation cohort, the correlation and agreement between AVC CAC and AVC Corrected were good (ICC = 0.939; 95% CI: 0.881–0.969; kappa = 0.700; 95% CI: 0.469–0.931). Conclusion The quantification of AVC Corrected using contrast enhanced CTA is feasible using a systematic approach with very good reliability and good agreement with AVC CAC . Larger-scale validation studies are needed to determine whether the use of AVC CAC can be eliminated in favour of AVC Corrected .

Endovascular aneurysm repairs lacking suitable common iliac artery landing zones occasionally require graft limb extension into the external iliac artery, covering the internal iliac artery origin. The purpose of this study was to assess incidence of type II endoleak following simple coverage of internal iliac artery without embolization during endovascular aneurysm repair. Three hundred eighty-nine endovascular aneurysm repairs performed by a single surgeon (2004–2015) were reviewed. Twenty-seven patients underwent simple internal iliac artery coverage. Type II endoleak was assessed from operative reports and follow-up computed tomography imaging. No patient suffered type II endoleak from a covered internal iliac artery in post-operative computed tomography scans. Follow-up ranged from 0.5 to 9 years. No severe pelvic ischemic complications were observed. In conclusion, for selected cases internal iliac artery coverage without embolization is a safe alternative to embolization in endovascular aneurysm repairs, where the graft must be extended into the external iliac artery.

Impaired illness insight in schizophrenia is associated with non-adherence and worse outcomes. Schizophrenia patients also exhibit error-monitoring deficits, which have been proposed to cause poor insight. To test this hypothesis, we examined whether schizophrenia patients' deficits in neurophysiological error-monitoring indices, the error-related negativity (ERN) and error positivity (Pe) event-related potential (ERP) amplitudes, are associated with impaired insight. ERPs were recorded in 18 schizophrenia patients and 18 normal comparison participants during a Stroop task. Patients' subnormal ERN and Pe amplitudes did not correlate with insight, suggesting that impaired insight in schizophrenia stems from neurocognitive mechanisms other than deficient error monitoring. Canadian Institutes of Health Research (INO-112359)