We produced a model of normal eye growth in term-born subjects. Relative to normal, the ROP eye is characterized by delayed, abnormal growth.
Purpose Because preterm birth and retinopathy of prematurity (ROP) are associated with poor visual acuity (VA) and altered foveal development, we evaluated relationships among the central retinal photoreceptors, postreceptor retinal neurons, overlying fovea, and VA in ROP. Methods We obtained optical coherence tomograms (OCTs) in preterm born subjects with no history of ROP (none; n = 61), ROP that resolved spontaneously without treatment (mild; n = 51), and ROP that required treatment by laser ablation of the avascular peripheral retina (severe; n = 22), as well as in term born control subjects (term; n = 111). We obtained foveal shape descriptors, measured central retinal layer thicknesses, and demarcated the anatomic parafovea using automated routines. In subsets of these subjects, we obtained OCTs eccentrically through the pupil ( n = 46) to reveal the fiber layer of Henle (FLH) and obtained adaptive optics scanning light ophthalmograms (AO-SLOs) of the parafoveal cones ( n = 34) and measured their spacing and distribution. Results Both VA and foveal depth decreased with increasing ROP severity (term, none, mild, severe). In severe subjects, foveae were broader than normal and the parafovea was significantly enlarged compared to every other group. The FLH was thinner than normal in mild (but not severe) subjects. VA was associated with foveal depth more than group. Density of parafoveal cones did not differ significantly among groups. Conclusions Foveal structure is associated with loss of VA in ROP. The preserved FLH in severe (relative to mild) eyes suggests treatment may help cone axon development. The significantly larger parafovea and increased outer nuclear layer (ONL) thickness in ROP hint that some developmental process affecting the photoreceptors is not arrested in ROP but rather is supranormal.
Purpose To study the relation between retinal and tunica vasculosa lentis (TVL) disease in ROP. Although the clinical hallmark of retinopathy of prematurity (ROP) is abnormal retinal blood vessels, the vessels of the anterior segment, including the TVL, are also altered. Methods ROP was induced in Long Evans pigmented and Sprague-Dawley albino rats; room-air-reared (RAR) rats served as controls. Then, fluorescein angiographic images of the TVL and retinal vessels were serially obtained with a scanning laser ophthalmoscope (SLO) near the height of retinal vascular disease, ∼20 days-of-age, and again at 30 and 64 days-of-age. Additionally, electroretinograms (ERGs) were obtained prior to the first imaging session. The TVL images were analyzed for percent coverage of the posterior lens. The tortuosity of the retinal arterioles was determined using Retinal Image multiScale Analysis (RISA; Gelman et al., 2005). Results In the youngest ROP rats, the TVL was dense, while in RAR rats, it was relatively sparse. By 30 days, the TVL in RAR rats had almost fully regressed, while in ROP rats it was still pronounced. By the final test age, the TVL had completely regressed in both ROP and RAR rats. In parallel, the tortuous retinal arterioles in ROP rats resolved with increasing age. ERG components indicating postreceptoral dysfunction, the b-wave and oscillatory potentials (OPs), were attenuated in ROP rats. Conclusions These findings underscore the retinal vascular abnormalities and, for the first time, show abnormal anterior segment vasculature in the rat model of ROP. There is delayed regression of the TVL in the rat model of ROP. This demonstrates that ROP is a disease of the whole eye.
depression is detected and treated), but it is also well known that some doctors find it is easier to emphasise "somatic" reasons to keep problems connected with the treatment of suicidal patients away from themselves. The problems of countertransference with those patients have been described widely."Like Davis and Kosky we think that it is necessary to investigate hospital records, not only the officially published data, to estimate the incidence of suicide attempters. However, while this can show changes in a particular institution over time, basically it is an institution-centred approach . To some degree such research will reflect the rate of suicide attempts in the catchment area, but it is not the same as the rate in a geographically defined area, as the title of the paper suggests.From our findings in Vienna we conclude that official data cannot be used alone, as has been done by the authors in Perth. (They mention themselves that some of their data now are out of date.) As they could not prove that the registration (and therefore the suggested percentage of missing suicide attempts) in Perth was the same in 1971 and 1986, we think that it is not possible to draw conclusions from those data about changes of rates, or the distribution of age groups or sexes.
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