Duplex Color Doppler Evaluation of Retinal Arterial Blood Flow in Type 2 Diabetic Subjects without Retinopathy.

Background: Diabetic retinopathy is a vascular disorder affecting the microvasculature of retina. It is caused by changes in the blood vessels of retina. If untreated, it may lead to blindness which is usually preventable if retinopathy is diagnosed early and treated promptly. In ophthalmology, color Doppler imaging is a new method that enables us to assess the orbital vasculature. It allows for simultaneous two dimensional anatomical and Doppler evaluations of hemodynamic characteristics of retinal artery. Objective: To observe the difference between Doppler flow velocity indices (peak systolic velocity, end diastolic velocity and resistive index) of retinal artery in type 2 diabetic subjects without retinopathy and those of normal controls. Materials and Methods: This case-control study was carried out in the department of Radiology and Imaging, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM) in collaboration with Ophthalmology Outpatient Department, BIRDEM, Dhaka from July 2011 to June 2013. Eighty diabetic patients without retinopathy aged 27–68 years were enrolled as cases and age and sex matched 80 healthy subjects were selected as controls. Type 1 diabetic patients, type 2 diabetics with retinopathy, hypertensive and dyslipidemic subjects were excluded from the study. All the selected subjects underwent duplex Doppler ultrasonography of both eyes using 5 to 7.5 MHZ linear phase transducer. Duplex color Doppler findings including spectral analysis (PSV, EDV and RI) were recorded. Unpaired t test was done to compare blood flow velocity indices of retinal artery in type 2 diabetic patients without retinopathy and that of healthy control subjects. p value <0.05 was considered as significant. Results: Majority (42.5% and 47.5%) of subjects were in 4th decade of life in both groups with predominance of males. The mean duration of diabetes was 4.56 ± 2.1 years. Mean peak systolic velocity (PSV) in 80 diabetic patients without retinopathy was 10.70 ± 1.50 cm/sec ranging 5.30–16.10 cm/sec and that of 80 healthy subjects was 11.27 ± 0.98 cm/sec ranging 9.0–13.10 cm/sec. Mean end diastolic velocity (EDV) in 80 diabetic patients without retinopathy was 2.58 ± 0.67 cm/sec ranging 1.00 –5.10 cm/sec and that of 80 healthy subjects was 4.11 ± 2.7 cm/sec ranging 3.00–4.60 cm/sec. Mean resistive index (RI) in 80 diabetic patients without retinopathy was 0.75 ± 0.04 ranging 0.66–0.81 and that of 80 healthy subjects was 0.64 ± 0.02 ranging 0.60–0.70. Mean difference of retinal arterial RI of diabetic subjects without retinopathy and healthy control eyes was statistically significant (p<0.001). Conclusion: From the present study it can be concluded that, there is statistically significant difference between retinal arterial RI of type 2 diabetic patients without retinopathy and that of healthy control adult subjects.

Ultrasonographic determination of amniotic fluid volume in normal pregnancy.

Ultrasonographic assessment of amniotic fluid has important implications because documentation of abnormalities of amniotic fluid volume may provide valuable information to enhance fetal health assessment. But in our country no study was conducted to establish normal values of amniotic fluid volume. So, this study was designed to find out normal values of amniotic fluid volume at various stages of gestation. The study was conducted in the department of Radiology and Imaging, BIRDEM in collaboration with the department of Obstetrics and Gynaecology, BIRDEM from 1(st) July, 2001 to 30(th) June, 2002. One hundred and twenty patients of normal pregnancy between 15 to 38 weeks' gestation were scanned by ultrasonography and their amniotic fluid volume was measured. For each gestational age between 15 and 38 weeks, 5 patients were recruited, and only one examination was done per pregnancy. Currently, the three semi-quantitative methods of assessing amniotic fluid volume include the amniotic fluid index (AFI), single deepest pocket (SDP) and two diameter pocket (TDP). Amniotic fluid volume of the study population was measured by the three methods. The values were plotted against each week in tabulated form. Thus the normal range of amniotic fluid volume in three methods (AFI, SDP, TDP) across gestational age in normal pregnancies was established. The mean value of amniotic fluid volume in AFI, SDP and TDP were 13.224 cm, 4.679 cm and 19.252 cm(2) respectively. AFI and SDP showed amniotic fluid volume increased with increasing gestational age up to early third trimester, but volume decreased thereafter. The prevalence of false positive result for oligohydramnios was 0.83% for AFI, 0% for SDP and 23% for TDP. The prevalence of false positive result for hydramnios was 1.66% for AFI, 0.83% for SDP and 0% for TDP. Thus the normal values of amniotic fluid volume for each of the three ultrasonographic techniques in the perspective of our country were obtained from the study. As the study was conducted with a limited number of patients, further study may be carried out with a large number of observations to reevaluate the results of the study.

Preoperative discrimination of benign and malignant ovarian tumors using color Doppler sonography and its correlation with histopathology.

A total of forty clinically diagnosed ovarian tumors were studied over a period of one year. The study aimed at evaluating the efficacy of trans-vaginal color Doppler sonography (TV-CDS) in preoperative discrimination of benign and malignant ovarian tumors and to correlate the imaging findings with postoperative histopathological findings. The pulsatility Index (PI) and Resistive Index (RI) were studied as primary effecacy variables of TV-CDS. In the present study, using TV-CDS, 72.5% of the ovarian tumors were found benign and 22.8% were malignant which were significantly correlated with postoperative histopathological findings. The average PI for benign and malignant tumors were 1.98 and 0.77 respectively and RI for benign and malignant tumors were 0.62 and 0.41 respectively. The low PI and RI values in malignant tumors as compared to benign ones were statistically highly significant (p < 0.001). The validity tests for TV-CDS were found to be 90% sensitive, 100% specific and 97% accurate. The study concludes that TV-CDS is a useful imaging diagnostic modality in preoperative discrimination of benign and malignant ovarian tumors due to its excellent characterization of tumors neo-vascularization.