Carotid Arterial Flow in Pseudoexfoliation Glaucoma and its Role in Diagnosing the Disease.

OBJECTIVE OF THE STUDY: The objective of the study was to investigate the change in carotid arterial flow in pseudoexfoliation glaucoma (XFG) for determining its diagnostic value. MATERIALS AND METHODS: Patients with XFG (N=30) and control subjects (N=22) were recruited. Common carotid artery (CCA) and internal carotid artery of each participant were examined using color Doppler and B-mode ultrasonography. Resistivity index (RI), as a flow parameter of interest, was measured and statistically compared between the 2 groups. Receiver operating characteristic was also produced to assess its diagnostic value. RESULTS: The measured RI values from the controls were within the expected range. Among CCA and internal carotid artery, only RI of CCA exhibited statistically significant changes in XFG (0.75±0.04 vs. 0.70±0.03 cm/s). Threshold value of RI=0.72 yielded 90% sensitivity and 73% specificity in distinguishing the cases of XFG from the controls. CONCLUSIONS: Flow dynamics of carotid arterial system exhibits different characteristics in individuals with XFG than controls. Such differences may serve as a basis for developing potentially new diagnostic biomarkers of XFG. Further studies are justified for examining the carotid flow in pseudoexfoliation syndrome and compare it against XFG for determining its power in differential diagnosis.

Ophthalmic artery blood flow parameters in pseudoexfoliation glaucoma.

PURPOSE: To investigate orbital flow parameters of ophthalmic artery (OA) in patients with pseudoexfoliation glaucoma (XFG) by ultrasonography. METHODS: This case-control study included 38 patients with XFG and 32 healthy control subjects. Color Doppler imaging was performed to evaluate orbital flow parameters of OA. Receiver operating characteristic analyses were performed to define the best cutoff value. RESULTS: In the XFG group, decreased peak systolic velocity (p = 0.114), end diastolic velocity (p = 0.002), and increased resistivity index (RI) (p<0.001) at OA compared to healthy controls were observed. A cutoff value 0.72 for OA RI was found to have a sensitivity of 66% and specificity of 94%. CONCLUSIONS: The results support the findings of increased vascular resistance in OA XFG. High sensitivity and specificity obtained for OA RI may be useful in evaluation of future therapeutic vascular agents.

Diagnostic accuracy and tolerability of contrast enhanced CT colonoscopy in symptomatic patients with increased risk for colorectal cancer.

OBJECTIVE: We compared the accuracy and tolerability of intravenous contrast enhanced spiral computed tomography colonography (CTC) and optical colonoscopy (OC) for the detection of colorectal neoplasia in symptomatic patients for colorectal neoplasia. METHODS: A prospective study was performed in 48 patients with symptomatic patients with increased risk for colorectal cancer. Spiral CTC was performed in supine and prone positions after colonic cleansing. The axial, 2D MPR and virtual endoluminal views were analyzed. Results of spiral CTC were compared with OC which was done within 15 days. The psychometric tolerance test was asked to be performed for both CTC and colonoscopy after the procedure. RESULTS: Ten lesions in 9 of 48 patients were found in CTC and confirmed with OC. Two masses and eight polyps, consisted of 1 tubulovillous, 1 tubular, 2 villous adenoma, 4 adenomatous polyp, 4 adenocarcinoma, were identified. Lesion prevalence was 21%. Sensitivity, specificity, accuracy, positive and negative predictive values were found 100%, 87%, 89%, 67% and 100%, respectively. Psychometric tolerance test showed that CTC significantly more comfortable comparing with OC (p=0.00). CTC was the preferred method in 37% while OC was preferred in 6% of patients. In both techniques, the most unpleasant part was bowel cleansing. CONCLUSION: Contrast enhanced CTC is a highly accurate method in detecting colorectal lesions. Since the technique was found to be more comfortable and less time consuming compare to OE, it may be preferable in management of symptomatic patients with increased risk for colorectal cancer.