Quantitative assessment of outer retinal folds on enface optical coherence tomography after vitrectomy for rhegmatogenous retinal detachment.

We aimed to investigate the possible causes of metamorphopsia for rhegmatogenous retinal detachment (RRD) based on findings of enface optical coherence tomography (OCT). The study was a retrospective, consecutive case series of 33 eyes with macula-off RRD. Metamorphopsia was measured by M-CHARTS and enface OCT images covering a macular area of 6 × 6 mm square obtained at 1, 3, and 6 months postoperatively. Within the outer retinal slabs of enface OCT, multiple lines that looked like folds were delineated in all eyes at month 1, and we succeeded in extracting images of folds by subtracting retinal vessels. We calculated their density by an image-processing technique. The mean M-CHARTS scores were 0.62 ± 0.47 at month 1 and 0.30 ± 0.29 at month 6 (P < 0.001). The fold density was 8.3 ± 4.2 at month 1 and 6.1 ± 3.1 at month 6 (P = 0.0044). The M-CHARTS scores at 6 months were significantly associated with the fold density at 1 month (r = 0.515, P = 0.002). In conclusion, enface OCT visualized the outer retinal folds in eyes that had undergone successful RRD surgery, and a larger number of folds was related to the remaining metamorphopsia.

Assessment of the hepatic arterial and portal venous blood flows during pregnancy with Doppler ultrasonography.

PURPOSE: The aim of this study was to evaluate whether the dual hepatic blood supply is altered in healthy pregnant women compared with that in nonpregnant women. MATERIALS AND METHODS: Flow wave-forms in common hepatic artery and portal vein were obtained in 67 healthy pregnant women at 10-40 weeks gestation and 22 nonpregnant women by using Doppler ultrasonography. RESULTS: In the nonpregnant group, the mean (SD) hepatic arterial blood flow, portal venous blood flow, and total liver blood flow were 0.57 (0.31) L/min, 1.25 (0.46) L/min, and 1.82 (0.63) L/min, respectively. In the healthy pregnant group, the portal venous blood flow and total liver blood flow significantly increased after 28 weeks gestation. However, the hepatic arterial blood flow remained unchanged during pregnancy. There was no relationship between the hepatic arterial blood flow and the portal venous blood flow. CONCLUSION: The results demonstrated that the hepatic perfusion increased during third trimester compared to nonpregnant level. Because the hepatic arterial blood flow remained unchanged during pregnancy, major determinant of the increase in the hepatic perfusion was the portal venous return. The data suggest that the hepatic arterial and portal venous vascular territories have regulatory mechanisms that allow for independent changes during pregnancy.

Two-dimensional thick-slice MR digital subtraction angiography for assessment of cerebrovascular occlusive diseases.

Although spatial resolution of current MR angiography is excellent, temporal resolution has remained unsatisfactory. We evaluated clinical applicability of 2D thick-slice, contrast-enhanced subtraction MR angiography (2D-MR digital subtraction angiography) with sub-second temporal resolution in cerebrovascular occlusive diseases. Twenty-five patients with cerebrovascular occlusive diseases (8 moyamoya diseases, 10 proximal internal carotid occlusions, and 2 sinus thromboses ) were studied with a 1.5-T MR unit. The MR digital subtraction angiography (MRDSA) was performed per 0.97 s continuously just after a bolus injection of 15 ml of gadolinium chelates up to 40 s in sagittal (covering hemisphere) or coronal planes. Subtraction images were generated at a workstation. We evaluated imaging quality and hemodynamic information of MRDSA in comparison with those of routine MR imaging, non-contrast MR angiography, and X-ray intra-arterial DSA. Major cerebral arteries, all of the venous sinuses, and most tributaries were clearly visualized with 2D MRDSA. Also, pure arterial phases were obtained in all cases. The MRDSA technique demonstrated prolonged circulation in sinus thromboses, distal patent lumen of proximal occlusion, and some collateral circulation. Such hemodynamic information was comparable to that of intra-arterial DSA. Two-dimensional thick-slice MRDSA with high temporal resolution has a unique ability to demonstrate cerebral hemodynamics equivalent to that of intra-arterial DSA and may play an important role for evaluation of cerebrovascular occlusive diseases.

Detection rate of the cervical gland area during pregnancy by transvaginal sonography in the assessment of cervical maturation.

OBJECTIVES: To detect the cervical gland area during normal pregnancy, and to determine its detection rate and relationship with cervical maturation. DESIGN: This was a mixed longitudinal and cross-sectional sonographic study involving a total of 514 transvaginal scans performed for detection of cervical gland area and measurement of cervical length in 260 normal singleton pregnancies at 16-41 weeks of gestation. The conventional cervical maturation index was measured simultaneously by digital examination. RESULTS: The detection rate of cervical gland area remained practically constant until the 31st week of pregnancy, but significantly decreased thereafter. Highly significant correlations were noted between the detection rate of cervical gland area and cervical length, cervical gland area and cervical maturation index, and cervical length and cervical maturation index. CONCLUSIONS: This study showed for the first time that cervical gland area can be detected sonographically and that its absence might be a predictor of preterm labor.

Pancreatic ductal adenocarcinoma: preoperative assessment with helical CT versus dynamic MR imaging.

PURPOSE: To compare helical computed tomography (CT) and dynamic, magnetic resonance (MR) imaging in the evaluation of pancreatic ductal adenocarcinoma. MATERIALS AND METHODS: Dynamic MR images obtained with breath holding, 256 phase- and 512 frequency-encoding steps, 5-mm section thickness, phased-array multicoil, and double-dose gadolinium were available from 21 patients. Dynamic MR images were retrospectively compared with helical CT images in the evaluation of tumor detection, local tumor extension, and vascular involvement. RESULTS: Tumors were detected on dynamic MR images of 19 of 21 (90%) patients and on helical CT scans of 16 (76%) patients. Dynamic MR imaging had equal or better sensitivity, accuracy, and agreement of tumor grade than did helical CT in the comparison of imaging findings and histopathologic findings. Dynamic MR imaging also had equal or better specificity than had helical CT in determination of local tumor extension and vascular involvement, except in the factors of duodenal invasion and portal venous system involvement. However, there was no statistically significant difference among any of these measurements. CONCLUSION: Dynamic MR imaging may be better than helical CT in the preoperative detection and evaluation of local tumor extension and of vascular involvement of pancreatic ductal adenocarcinomas.

An Economic Analysis of Water and Sanitation Infrastructure Improvements in the Colonias of El Paso County, Texas.

The authors conducted a cost-benefit analysis of a project to improve water supply and sanitation infrastructure in a rural community (colonia) along the United States-Mexico border. The present value of total costs in the scenario without improvements was $42,937,507, compared with net costs with improvements of $34,600,800. It is estimated that improved access to safe drinking water and solid waste sanitation prevented 155 cases of hepatitis A and 5,165 cases of gastrointestinal illness over 26 years and saved $846,541 in associated health care costs, approximately 10% of the total estimated savings. The majority of benefits was in the form of time savings and increased land values. The authors did not consider the value of improving environmental conditions for future generations and preventing communicable disease epidemics associated with poor sanitation. Accurate value estimates for these benefits might strengthen the argument for undertaking similar infrastructure-improvement projects in the colonias and in other underdeveloped rural areas of the United States. cost-benefit analysis; water supply and sanitation; health care costs; disease-prevention effectiveness Hanley & Belfus, Inc. Int J Occup Environ Health 1077-3525 2 3 1996 July/September Decreases in Subpopulations of T Lymphocytes and Natural Killer Cells in the Blood of Retired Chromate Workers 222 225 EN Takeshi Tanigawa Shunichi Araki Department of Public Health, Faculty of Medicine, University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan. Akinori Nakata Takaharu Araki Susumu Sakurai To examine the effects of past exposure to chromates on lymphocyte subpopulations in man, the authors measured subpopulations of T lymphocytes and natural killer (NK) cells by flow cytometry together with B lymphocytes in blood samples from 27 male workers and 22 healthy controls. All subjects were nonsmokers. The numbers of CD4+CD45RA+ (suppressor-inducer), CD8+ (suppressor/cytotoxic) and total T lymphocytes, CD16+CD57+ NK cells, and total lymphocytes in the blood of chromate workers were significantly smaller than those in the blood of healthy controls (analysis of covariance with age as a covariate). It is suggested that suppressor-inducer and suppressor/cytotoxic T lymphocytes and NK cells with intermediate NK cell activity are most susceptible to the effects of past exposure to chromates as compared with other lymphocyte subpopulations such as B and CD4+CD29+ T lymphocytes.

Postaortic left innominate vein: radiological assessment and pathogenesis.

Postaortic left innominate vein (PALIV) is a rare venous anomaly and the findings on plain chest radiographs have not been well described. Plain chest radiographs, CT and MR of nine adults known to have PALIV were reviewed. They all showed a high aortic arch, including four with a right-sided aortic arch and one with a double aortic arch, in postero-anterior radiographs, and seven showed curved shadows in the left upper mediastinum. On all lateral chest radiographs (n = 5), the superior retrosternal region was opacified by the high aortic arch. CT or MR images confirmed the aortic arch and/or innominate artery to be in that part of the retrosternal space, normally occupied by the left innominate vein, in all cases. Association of a curved shadow in the superior mediastinum with a high aortic arch on plain chest radiographs is therefore suggestive of, though not diagnostic for, PALIV. This entity was well documented by CT or MR and the radiological findings were considered to imply that developmentally PALIV is secondary to a high position of the aortic arch.