Confocal scanning laser ophthalmoscope imaging superimpose two or three kinds of lasers to obtain images of different layers of retina, and then synthesize a pseudo-color fundus image by computer. Confocal scanning laser ophthalmoscope is widely used in outpatient fundus pre-examination and epidemiological screening of large samples due to its features of non-mydriatic, fast imaging, simple operation and high degree of patient cooperation. It has good clinical and scientific application value in the diagnosis and treatment of a variety of fundus diseases. Because of there is still a lack of unified standards for laser fundus photos in China, it is necessary to correctly identify the common fundus lesions in confocal scanning laser ophthalmoscope and to summarize and popularize the method of reading the photos in layers. In addition, we should give full play to the its advantage of layering and locating, and reasonably choose the combination of OCT, OCT angiography, FFA, ICGA, ultrasonography, so as to maximize its clinical application value and help clinical diagnosis.
Objective To study on the ultrastructural characteristic of segments of photoreceptors from neonatal retinas for supporting donor retina choice of retinal transplantation. Methods Photoreceptors from neonatal calf and adult calf were analysed by scanning electron microscopy and transmission electron microscopy. Results Segments of photoreceptors from neonatal calf appeared the mushroom pattern, in which, distal end of outer segment which was ball-shaped formed the head with mushrooms appearance, and the inner segments along with some of outer segments formed the body with mushrooms appearance. Within the outer segment, plasma membranes of adjacent evaginations form a disk subsequently. The a rray of most disks were vertical to the entire length of segments, but some were parallel and slope to.Owing to the incomplete formation, some rim of disk near distal end of outer segment revealed step-shaped appearance. The distal end of outer segment displays some processes consisted of membranous discs, much vesicular material and mitochondria, much rough endoplasmic reticulum (RER) and numerous polyso mes.Segments of photoreceptor connected with outer nuclear layer via the external limiting membrane. Conclusion The typical morphol ogical structures of outer segments suggest the immature and b gowth ability of photoreceptors of the retina of neonatal calf, and therefore the competence for donor material of retinal transplantation. (Chin J Ocul Fundus Dis, 2001,227-229)
Objective To verify the applicable significance of confocal scanning laser retinal tomography in agerelated macular degeneration (AMD). Methods Heidelberg confocal scanning laser tomography was used to measure 75 eyes of 59 patients with AMD, including 25 eyes of 20 patients with exudative AMD, 25 eyes of 16 patients with atrophic AMD, and 25 eyes of 23 patients with macular drusen. The differences of the width, volume and maximum height of Z profile signal of macula were analyzed. Results Z profile signal width in macular tomography of exudative AMD was wider than that of macular drusen; maximum height and volume in macular tomography of exudative AMD were larger than that of macular drusen (P<0.01); Z profile signal width, maximum height,and volume in macular tomography of atrophic AMD were wider and larger than that of macular drusen (P<0.05). Macular volume of exudative AMD was obviously larger than that of atrophic AMD (P<0.01). Conclusion Confocal scanning laser tomography may be one of the useful methods for objective evaluation of morphologic change for the development of AMD. (Chin J Ocul Fundus Dis, 2002, 18: 262-265)
Diabetic retinopathy (DR) is one of the most common causes of visual impairment and blindness in diabetic patients. It is particularly important to set up simpler, safer, non-invasive and highly effective methods for diagnosis as well as monitoring DR. A variety of new fundus imaging techniques show great advantages in early diagnosis, treatment and monitoring of DR in recent years. The main characteristics of wide-field scanning laser imaging system is achieving a large range of retinal image in a single photograph and without mydriasis. It provides several options for color images, FFA and FAF, which satisfy to detect the retina, choroid and vascular structure. Multi spectral fundus imaging system is suitable for DR screening, because it is able to recognize the typical characteristics of DR, such as microaneurysms, hemorrhage and exudation, and is non-invasive and convenient. OCT angiography is a quantitative examination that provides foveal avascular zone area, macular blood flow density, which provides strong evidence for DR diagnosis. The improvement of these new techniques will help us to build up a personalized evaluation system of DR.
Objective To test the hypothesis that the macular pigment may be a marker of foveal cone function and consequently the structural integrity of foveal cones.Methods Sixteen patients (32 eyes) diagnosed to have Stargardt dystrophy and three patients with full thickness macular holes by clinical criteria were studied with a scanning laser ophthalmoscopy (SLO) comparing argon laser blue and infrared images for the presence or absence of macular pigment (MP) in the fovea. An C++ computer based program was used to evaluate the density of MP. Eyes were graded into three categories: those without foveal macular pigment, those with partial pigment and those with normal amounts of macular pigment. These categories were compared with visual acuity determined by the Snellen chart. Results Thirteen eyes with a visual acuity of 20/200 or worse had no macular pigment in the fovea. Eleven eyes with visual acuity of 20/40 or better had a normal amount of macular pigment in the fovea and 1 eye had partial macular pigment. Eleven eyes with partial macular pigment had intermediary acuity value.Conclusions Foveal macular pigment is closely related to foveal cone acuity and therefore may be a marker for the presence of foveal cones. Infrared light is a sensitive indicator of early macular diseases.(Chin J Ocul Fundus Dis,2003,19:201-268)