Soh Futagami

Patchy atrophy and lacquer cracks predispose to the development of choroidal neovascularisation in pathological myopia

Aims: To determine the incidence and predisposing findings for choroidal neovascularisation (CNV) in a large series of highly myopic patients. Methods: The medical records of 218 consecutive patients (325 eyes) with myopic fundus changes in the macula were reviewed. The incidence of CNV during a follow up of at least 3 years of highly myopic patients and identification of predisposing findings for the development of myopic CNV were examined. Results: Among 325 highly myopic eyes examined, 33 eyes (10.2%) developed myopic CNV. The incidence was higher (34.8%) among the fellow eyes of patients with pre-existing CNV than among eyes of patients without pre-existing CNV (6.1%). CNV developed in 3.7% with diffuse chorioretinal atrophy, in 20.0% with patchy atrophy, and in 29.4% with lacquer cracks. Conclusion: Approximately one in 10 highly myopic eyes developed myopic CNV in average 130.2 months. Patchy atrophy and lacquer cracks were shown to be important predisposing findings for CNV development.

Prevalence and characteristics of foveal retinal detachment without macular hole in high myopia.

PURPOSE To report the prevalence of foveal retinal detachment without macular hole in a large number of highly myopic eyes using optical coherence tomography (OCT), and to clarify the demographic characteristics associated with foveal retinal detachment in these eyes. DESIGN A consecutive, prospective, observational case series. METHODS In 134 eyes of 78 consecutive patients with high myopia (refractive error of -8 diopters or more), we performed complete ophthalmic examinations and studied cross-sectional images of the macula with OCT. The patients were divided into two groups according to the presence (group 1, n = 78 eyes of 45 patients) or absence (group 2, n = 56 eyes of 33 patients) of posterior staphyloma. Slit-lamp examination with a Goldmann three-mirror lens indicated that none of the eyes had a macular hole. RESULTS In seven of 78 eyes (9.0%) with posterior staphyloma (group 1), OCT revealed foveal retinal detachment. Two of the seven eyes had foveal retinoschisis. Optical coherence tomography revealed no retinal detachment or retinoschisis in any eye without posterior staphyloma (group 2). Visual acuity of the seven eyes with foveal retinal detachment ranged from 20/40 to 20/200. Two of the seven eyes had visual acuity 20/50 or better. No patients complained of recent, progressive visual impairment. All seven eyes with foveal retinal detachment had severe myopic fundus changes (focal chorioretinal atrophy or bare sclera). CONCLUSIONS In highly myopic eyes with posterior staphyloma, the prevalence of foveal retinal detachment without macular hole was 9.0%. In eyes with this type of retinal detachment, visual acuity varies and foveal retinal detachment tends to be missed on routine examination. Periodic examination using OCT is recommended for highly myopic eyes with severe myopic degenerative changes and posterior staphyloma.

Reduction of retinal blood flow in high myopia

PurposeTo investigate changes in retinal vessel diameter and blood velocity in high myopia using laser Doppler velocimetry.MethodsThirty-nine subjects (39 eyes) were enrolled in the study. The subjects were divided into three groups according to their refractive status; 15 eyes (15 patients) with emmetropia (within ±3.0 diopters), 14 eyes (14 patients) with mild myopia (between −3.0 and −8.0 diopters), and 10 eyes (10 patients) with high myopia (>−8.0 diopters). Patient age was matched between groups. Blood velocity and vessel diameter of the upper or lower temporal retinal artery were measured using laser Doppler velocimetry with an eye-tracking system, and measurements were compared between groups.ResultsThe average retinal blood flow and vessel diameter in highly myopic eyes were significantly decreased compared with emmetropic eyes or mild myopic eyes (Mann-Whitney U test, p<0.05). Also, there was significant difference regarding retinal blood flow and vessel diameter between eyes with mild myopia and the other groups. In addition, there was no significant difference in blood velocity between the three groups.ConclusionsRetinal blood flow was decreased in high myopia, mainly due to the narrowing of the retinal vessel diameter. Impaired retinal blood flow might have a role in the development of chorioretinal atrophy in high myopia.

Characteristics of patients with a favorable natural course of myopic choroidal neovascularization

ObjectiveTo identify the characteristics of patients with myopic choroidal neovascularization (CNV) who had a favorable visual prognosis without treatment.MethodsWe reviewed the medical records of 52 consecutive patients (57 eyes) with myopic CNV who were followed for at least 5 years after the onset of CNV. Clinical characteristics (patient age, CNV size and location, visual acuity at onset, chorioretinal atrophy development around CNV, and degree of myopia) were compared between patients whose visual acuity 5 years after CNV onset was better than 20/40 and those whose visual acuity was worse than 20/200.ResultsAmong 57 eyes, eight eyes (14.0%; 8 patients) had a final visual acuity better than 20/40. On the other hand, 37 eyes (64.9%; 33 patients) had a final visual acuity worse than 20/200. Statistical analysis revealed that the patients with a good prognosis (final visual acuity better than 20/40) were significantly younger, had significantly smaller CNV, and significantly better initial visual acuity (Mann–Whitney U-test, p<0.05). Juxtafoveal CNV was more frequently observed in patients with a good prognosis than in those with a poor prognosis (Fisher’s exact probability test, p<0.05). Only one patient (12.5%) in the good prognosis group developed a very limited area of chorioretinal atrophy around the regressed CNV, while 91.9% of the patients in the poor prognosis group developed chorioretinal atrophy. Refractive status and the axial length measurements did not differ between the two groups.ConclusionsSome young patients with myopic CNV retain favorable vision over the long term without active treatment. These information might be useful to predict the visual outcome of patients with myopic CNV.

Fundus Characteristics of High Myopia in Children

PurposeTo evaluate the fundus characteristics of highly myopic eyes in children.MethodsWe reviewed the medical records of 46 children (1 to 8 years old; mean age, 6.8 years) (80 eyes) with high myopia (4 D or more for children younger than 5 years, 6 D or more for children aged 6–8 years) seen consecutively during a 10-year period at the high-myopia clinic in our hospital. Children of up to 8 years of age at the initial visit were included in the study.ResultsFundus examination revealed posterior staphyloma in only one eye (1.3%) and mild chorioretinal atrophy around the optic disc in 13 eyes (16.3%). There were no patients with choroidal neovascularization or geographic atrophy in the posterior fundus. Myopic peripapillary crescent was observed in 26 eyes (33.8%), but the area of the crescent was relatively small (mean, 0.5 disc area).ConclusionsThe results of the present study showed that myopic fundus changes are uncommon and mild in children. They suggest that aging, in addition to mechanical stretching of the eyeball, might be important for the development of myopic fundus changes. Jpn J Ophthalmol 2005;49:306–311© Japanese Ophthalmological Society 2005

Factors associated with the development of chorioretinal atrophy around choroidal neovascularization in pathologic myopia

PurposeTo examine the influencing factors on the development of chorioretinal atrophy, which is the main cause of long-term visual decrease in myopic choroidal neovascularization (CNV), in a large series of highly myopic patients.MethodsSixty-five patients (81 eyes) with myopic CNV were studied retrospectively. The influence of the patient’s age, refractive error, axial length, visual acuity at onset of CNV, size of CNV, and grade of myopic retinopathy on the extent of chorioretinal atrophy more than 3 years after CNV onset was investigated by means of multiple linear regression analysis.ResultsSeventy-seven of 81 eyes (95.1%) developed chorioretinal atrophy around myopic CNV during the follow-up period. Multiple linear regression revealed that age was the most influencing factor for the development of chorioretinal atrophy in all the subjects. When we divided the subjects into two groups according to their age, however, CNV size was the only factor to influence the development of chorioretinal atrophy in the patients younger than 40 years, whereas age was still the only influencing factor in those older than 40 years.ConclusionsThe factors influencing the development of chorioretinal atrophy differ according to patient age. Local factors, such as CNV size, determine the tendency to develop chorioretinal atrophy in young patients. Systemic factors, such as patient age, play a greater part in older subjects.

Peripapillary crescent enlargement in highly myopic eyes evaluated by fluorescein and indocyanine green angiography

Aims: To evaluate angiographic features of myopic crescents using fluorescein angiography (FA) and indocyanine green angiography (IA). Methods: FA and IA angiograms of 88 highly myopic eyes (47 consecutive patients) were reviewed. The follow up period ranged from 5–28 years. Results: FA revealed two zones of the myopic crescent: a consistently hypofluorescent inner zone and an outer zone with delayed choroidal filling. IA revealed dislocation of the Zinn-Haller ring to the border between the two zones. Myopic crescent enlargement occurred in 68.1%. Only the outer zone increased significantly in most of the eyes with enlarged crescents. Conclusions: The inner zone might develop as a result of mechanical stretching, and the outer zone might be the result a secondary circulatory disturbance and mechanical stretching.

Indocyanine Green Angiography of Retrobulbar Vascular Structures in Severe Myopia

PURPOSE To evaluate angiographic findings of retrobulbar arteries and veins in severely myopic patients. METHODS We examined 416 severely myopic eyes (213 patients) with refractive errors greater than -8.25 diopters using indocyanine green videoangiography. A control group of 74 eyes (37 patients) had refractive errors within plano +/- 3 diopters. Four severely myopic patients underwent computed tomographic angiography to identify the entire intraorbital course of retrobulbar veins. RESULTS Of 416 severely myopic eyes, 231 (55.5%) exhibited retrobulbar arteries, which were tortuous and pulsatile behind the posterior pole of the globe. Retrobulbar arteries connected directly with choroidal arteries temporal to the macular area. In 17 of these 231 eyes, retrobulbar arteries were also observed nasal to the optic nerve head, continuous with the Zinn-Haller ring around the optic nerve head and directly connected with choroidal arteries. In 39 severely myopic eyes (31 patients), indocyanine green angiography disclosed retrobulbar veins, most of which coursed vertically just behind the posterior pole of the globe. These retrobulbar veins originated as an inferior vascular network of the inferior orbital vein and drained into the superior orbital vein in the upper orbit. CONCLUSION Retrobulbar arteries observed in this study were temporal and nasal short posterior ciliary arteries. Only the lateral collateral vein, which was one of the collateral channels between the superior and inferior orbital veins, was visible in severely myopic eyes. Indocyanine green angiography is useful in evaluating retrobulbar vascular structure in severely myopic eyes.

The quality of life in patients with pathologic myopia

PURPOSE To evaluate the functional status in daily life and the quality of life (QOL) of pathologic myopia patients. METHODS A cross-sectional study was conducted using data of consecutive pathologic myopia patients (n = 200) and control subjects (n = 144). The influence of the disease on the daily life and the QOL of patients were evaluated using a self-rated questionnaire. The questionnaire covered the full range of daily life activity, including daily tasks depending on visual acuity, social and emotional handicaps, and cognition of disease, and the QOL of pathologic myopia patients. RESULTS The functional status in daily life and the QOL of patients were reduced compared with control subjects. The influence of pathologic myopia on a patients daily life was primarily the result of three major factors, handicap, disability, and support. All three factors correlated with the QOL, the degree of handicap having the strongest correlation. CONCLUSION The functional status in daily life and the QOL of pathologic myopia patients were reduced; this decline in QOL was attributed to handicap and disability caused by the ocular disease.

Zinn-Haller arterial ring observed by ICG angiography in high myopia

AIMS To delineate the entire Zinn–Haller arterial ring angiographically in vivo. METHODS 382 highly myopic eyes (210 patients) with refractive errors greater than −8.25 D were examined using indocyanine green (ICG) videoangiography. A control group of 80 eyes (40 patients) had refractive errors within plano +/− 3 D. RESULTS The Zinn–Haller ring was visible in 206 of 382 highly myopic eyes (53.9%) by ICG angiography. Although only a part of the Zinn–Haller ring was visible in 162 of 206 eyes, in the remaining 44 eyes it was observed almost completely around the optic nerve head. No anastomotic channels between lateral and medial short posterior ciliary arteries were filled by ICG angiography. In 22 of the 44 eyes (50.0%) the Zinn–Haller ring was supplied by branches of the lateral and medial short posterior ciliary arteries; in seven eyes, it was supplied only by the lateral short posterior ciliary artery; and in seven eyes, it was supplied only by the medial short posterior ciliary artery. In none of the control subjects was the Zinn–Haller ring visible by ICG angiography. CONCLUSIONS The Zinn–Haller ring observed by ICG angiography was not a complete collateral circle between lateral and medial posterior ciliary arteries. Also, the patterns in supply vessels to the Zinn–Haller ring varied. ICG angiography made possible the detailed observation of the Zinn–Haller ring in human eyes in vivo.