Biomedical subjects

A A Pyott

Publications and source records attributed to A A Pyott.

3 recordsLinked to original sources

PubMed1994

Detection of diabetic retinopathy by scanning laser ophthalmoscopy.

A scanning laser ophthalmoscope (SLO) was used to examine the fundi of 54 diabetic patients through undilated pupils and the results compared by an experienced ophthalmologist with clinical examination through dilated pupils to assess the effectiveness of the SLO in detecting diabetic retinopathy. Whilst the SLO was not as good at detecting cotton wool spots and subtle intraretinal microvascular abnormalities, it did not miss any active new vessel formation and all eyes needing treatment would have been referred.

Diabetic Retinopathy↗

PubMed1993

Inter-observer variation in clinical optic disc biometry.

This study investigated the inter-observer reproducibility of measurements of the optic nerve head as carried out with a clinical optic disc biometer. This instrument employs a modification of indirect ophthalmoscopy to enable measurement of fundus structures. Measurements were made independently by two observers on 84 eyes of 47 patients. The median inter-observer differences for each measurement were as follows: maximum disc diameter, 0.085 mm; minimum disc diameter, 0.080 mm; maximum cup diameter, 0.098 mm; minimum cup diameter, 0.078 mm; disc area, 0.225 mm2; neuroretinal rim area, 0.215 mm2. Utilising the above measurements, the instrument automatically calculates a 'rim index' to take account of variations in disc size. It then interprets the disc as normal, suspicious or glaucomatous. The optic disc biometer produced seriously conflicting interpretations in 8 discs, 7 of which had been judged by both observers to have indistinct boundaries of the disc or cup.

Biometry↗

PubMed1990

Real time ultrasound in the assessment of intraocular foreign bodies.

The accurate detection and localisation of retained intraocular foreign bodies (IOFB) is important in the planning of subsequent surgical management. Using a porcine eye model, the authors have compared the relative detection rates of real time ultrasonography and plain roentgenograms for a variety of IOFBs. With an overall detection rate of 93%, ultrasonography appears to be a considerably more sensitive investigative tool than plain roentgenograms (40%) for the imaging of IOFBs, particularly those that are non-metallic.

Animals↗