Abstract-Reliable and efficient optic disk localization and segmentation are important tasks in automated retinal screening. General-purpose edge detection algorithms often fail to segment the optic disk due to fuzzy boundaries, inconsistent image contrast or missing edge features. This paper presents an algorithm for the localization and segmentation of the optic nerve head boundary in low-resolution images (about 20µ per pixel). Optic disk localization is achieved using specialized template matching, and segmentation by a deformable contour model. The latter uses a global elliptical model and a local deformable model with variable edge-strength dependent stiffness. The algorithm is evaluated against a randomly-selected database of 100 images from a diabetic screening programme. Ten images were classified as unusable; the others were of highly variable quality. The localization algorithm succeeded on all bar one usable image; the contour estimation algorithm was qualitatively assessed by an ophthalmologist as having Excellent, Good or Fair performance in 83% of cases, and performs well even on blurred images.

Changes in retinal vessel diameter are an important sign of diseases such as hypertension, arteriosclerosis and diabetes mellitus. Obtaining precise measurements of vascular widths is a critical and demanding process in automated retinal image analysis as the typical vessel is only a few pixels wide. This paper presents an algorithm to measure the vessel diameter to sub-pixel accuracy. The diameter measurement is based on a two-dimensional difference of Gaussian model, which is optimized to fit a two-dimensional intensity vessel segment. The performance of the method is evaluated against Brinchmann-Hansen's half height, Gregson's rectangular profile and Zhou's Gaussian model. Results from 100 sample profiles show that the presented algorithm is over 30% more precise than the compared techniques and is accurate to a third of a pixel.

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Objective-To examine the traditional view that unawareness of hypoglycaemia and inadequate hypoglycaemic counterregulation in insulin dependent diabetes meilitus are manifestations of autonomic neuropathy.Design-Perspective assessment of unawareness of hypoglycaemia and detailed assessment of autonomic neuropathy in patients with insulin dependent diabetes according to the adequacy of their hypoglycaemic counterregulation.Setting-One routine diabetic unit in a university teaching hospital. IntroductionUnawareness of hypoglycaemia in diabetic patients is, by tradition, ascribed to autonomic neuropathy.'13 Some patients with insulin dependent diabetes mellitus have been shown to produce inadequate amounts of adrenaline and glucagon in response to hypoglycaemia, and these patients are more at risk from neuroglycopenia and hypoglycaemic coma.4 Diabetic autonomic neuropathy has also been suggested as the cause of defective adrenaline secretion in these patients,"7 and, in this way, as the cause of inadequate counterregulation. Previous studies investigating diabetic autonomic neuropathy and inadequate counterregulation have included only limited assessment of autonomic function, giving rise to conflicting results.89 We used an extensive battery of investigations of autonomic neuropathy to re-examine the relations among autonomic neuropathy, hypoglycaemic unawareness, and inadequate hypoglycaemic counterregulation.

Women and patients with previous genital fungal infections had higher risks of developing genital fungal infections with dapagliflozin treatment.

The acute effects of iv somatostatin (SRIH; 100 micrograms/h) on the urinary flow (Uvol), effective renal plasma flow (RPF), and glomerular filtration rate (GFR) were compared with those of a control infusion of 0.15 M NaCl in nine insulin-dependent diabetic (IDD) patients of less than 10 yr disease duration and six normal subjects (NS). RPF and GFR were measured using a standard primed constant isotope infusion of [125I]iodohippurate and [51Cr]chromium EDTA. Uvol, RPF, and GFR were measured during 20-min clearance periods. During the NaCl infusion mean Uvol, RPF, and GFR were 14.1 +/- 0.2 (+/- SEM), 708 +/- 4, and 150 +/- 1 mL/min in the IDD group and 12.7 +/- 0.4, 568 +/- 5, and 110 +/- 2 mL/min in the NS group, respectively. In the IDD patients Uvol, RPF, and GFR decreased from 16.6 +/- 1.8, 670 +/- 30, 146 +/- 4 mL/min pre-SRIH to 9.2 +/- 1 (P less than 0.001), 553 +/- 25 (P less than 0.001), and 130 +/- 5 (P less than 0.001) mL/min, respectively, at 120 min during the SRIH infusion. Similarly, in the NS group mean Uvol, RPF, and GFR were 14.2 +/- 0.6, 552 +/- 15, and 112 +/- 5 mL/min pre-SRIH and decreased to 7.4 +/- 0.6 (P less than 0.001), 422 +/- 7 (P less than 0.001), and 93 +/- 3 (P less than 0.001) mL/min, respectively, after 120 min of the SRIH infusion. SRIH, therefore, had a profound effect on renal function in both IDD patients and NS, resulting in a reduction in RPF, GFR, and, as a consequence, Uvol.

Two retinal cameras (Canon CR2 45NM and CR3 45NM) have recently become available and are capable of producing an instant colour photograph of a 450 field of retina, including the macula and optic disc, without dilatation of the pupils being necessary. The ability of each camera to detect diabetic retinopathy was compared with that of doctors in diabetic clinics using ophthalmoscopy during busy clinic hours. The CR3 was found to be considerably superior to the CR2 in terms of quality of photograph because it can use a smaller pupil. Overall, the detection rate ofthe camera was more than four times higher than that of ophthalmoscopy through undilated pupils and more than twice as high as that of ophthalmoscopy through dilated pupils. Lesions missed by ophthalmoscopy but detected by the camera included soft exudates and circinate rings of hard exudates, sometimes encroaching on the macula.

Six normal subjects received subcutaneous human, porcine, and bovine ultralente insulin (0.30 U/kg) and diluent (control) in randomized order. Plasma glucose, C-peptide, and insulin were measured for 32 h after injection. From 10 h onward human ultralente produced significantly lower plasma glucose levels (p less than 0.05-0.01) compared to bovine ultralente. Porcine ultralente produced an intermediate hypoglycaemic response up to 16 h and was similar to the bovine insulin from 24-32 h. Estimated exogenous insulin concentration was higher (p less than 0.05-0.001) following human ultralente compared to bovine ultralente between 2 and 22 h after injection. Up to 24 h the porcine preparation led to intermediate insulin levels, but becoming identical to bovine ultralente from 28-32 h. Peak mean exogenous insulin values for human, porcine, and bovine ultralente were 0.054, 0.044, and 0.023 nmol/l at 14, 16, and 18 h, respectively, reaching 0.022, 0.013, and 0.013 nmol/l at 32 h. The different pharmacokinetic behaviour of human and bovine ultralente insulin must be considered when initiating treatment with human ultralente or transferring patients from bovine to human ultralente.