Optical coherence tomography angiography (OCTA) is a new and non-invasive imaging technique that is able to detect blood flow signal in the retina and the choroid within seconds. OCTA is different from the traditional angiography methods. The major advantages of OCTA are that it can observe blood flow signal in different layers of the retina and the choroid without injecting any dye, provide blood flow information that traditional angiography cannot provide, and enrich pathophysiological knowledge of the retinal and choroidal vascular diseases., which help us to make an accurate diagnosis and efficient evaluation of these diseases. However there is a large upgrade potential either on OCTA technique itself or on clinical application of OCTA. We need to fully understand the advantage and disadvantage, and differences of OCTA and traditional angiography. We also need to know how to interpret the result of OCTA. With that we could make a fast diagnosis in a non-invasive way and improve our knowledge of the retinal and choroidal vascular diseases.
Objective To observe the spectral domain optical coherence tomography (SD-OCT) features of acute Vogt-Koyanagi-Harada (VKH) eyes before and after treatment.Methods Twenty-eight patients (56 eyes) with acute VKH diagnosed by slitlamp microscopy, B mode ultrasound and fundus fluorescein angiography (FFA) were enrolled in this study. All the patients were treated with steroid after diagnosis. SD-OCT was performed in all the patients before and after treatment. The follow-up was ranged from 12 to 32 weeks with a mean of (21.30plusmn;8.53) weeks. The foveal retinal detachment height, inner and outer segments (IS/OS) of photoreceptors, and the changes in retinal structure within the vascular arcades before and after treatment were comparatively analyzed. Results OCT examination results showed that before treatment, all eyes had retinal neural epithelial detachment. The average neural epithelial detachment height in the fovea was (635.44plusmn;340.04) mu;m. Forty-three eyes (76.8%) had different types of subretinal exudates; 41 eyes (73.2%) had b granular reflection in the subretinal space. Twenty-two eyes (39.3%) had paraforveal outer nuclear layer (ONL) thickening with finger-like protrusions attached with membrane-like structure. Thirty-three eyes (58.9%) had wavy lines of the retinal pigment epithelium (RPE). After the treatment, these exudates dissolved within one week and RPE line became straight. The retina reattached after (2.33plusmn;0.82) weeks. In most patients external limiting membrane and IS/OS became intact after (5.01plusmn;6.71) weeks and (11.40plusmn;7.89) weeks respectively. However, at the end of follow-up, 46 eyes (82.1%) still had focal areas of IS/OS defect and 11 eyes (19.6%) had focal ONL thinning. Conclusions Before the treatment, the OCT features of acute VKH are serous retinal detachment at fovea, different types of subretinal exudates and wavy RPE. After the treatment, the OCT features of acute VKH are exudates dissolving, straight RPE line and early recovery of external limiting membrane.
Objective To observe the choroidal thickness and its relationship with age and refraction status in Chinese population. Methods 180 healthy volunteers (360 eyes) were enrolled in this study. Based on the age, the volunteers were divided into A (20-29 years old), B (30-39 year old), C (40-49 years old), D (50-59 year old), E (60-69 year old), and F (70-85 year old) group, with 33, 31, 29, 30, 31, 26 volunteers respectively. And the volunteers were divided into ＜60 years old group with 123 volunteers and ge; 60 years old group with 57 volunteers. Enhanced depth imaging (EDI) choroidal scans were obtained in all eyes by using spectraldomain optical coherence tomography. Subfoveal choroidal thickness (CT) and CT at 1 mm/3 mm temporal, nasal, superior, inferior to the fovea (S 1 mm, I1 mm, T1 mm, N 1 mm, S, I3 mm, T3 mm, N3 mm) were measured. The differences of CT between different quadrants, genders, eyes and ages were comparatively analyzed. The correlations between age, refraction status and CT in the volunteers of ＜60 years old and ge; 60 years old group were analyzed. Results The subfoveal CT was (262.78plusmn;84.38) mu;m. The differences were significant between subfoveal CT and all the quadrants CT (P＜0.05) except for S1 mm and T1 mm (P＞0.05 ). There was no difference between genders or eyes in subfoveal CT (P＞0.05 ). There was no difference between A, B, C, D group in subfoveal CT (P＞0.05 ). The subfoveal CT of E and F group were thinner than A, B, C, D group (P＜0.05). In the ＜60 years old group, there was a positive correlation between refraction status and CT (r=0.147,P＜0.05); but no correlation between age and CT (r=－0.055, P＞0.05 ). In the ge; 60 years old group, there was a significant negative correlation between CT and age (r=－0.543, P＜0.05), but no correlation between refraction status and CT (r=-0.008, P＞0.05). Conclusions The average subfoveal CT in Chinese population was (262.78plusmn;84.38) mu;m. The refraction status is the main influence factors in subjects ＜60 years old, while the age is the main influence factors in subjects ge;60 years old.
Idiopathic macular hole (IMH) refers to full thickness defects of retina in macular area with no clear reasons. The management of IMH includes vitrectomy combined with internal limiting membrane (ILM) peeling and pharmacological vitreolysis. But ILM peeling may damage the inner retina; novel techniques, such as inverted ILM flap technique and foveola non-peeling ILM surgery, autologous ILM transplantation had made the method of ILM peeling more diversified with less damage. Pharmacological vitreolysis targeting fibronectin and laminin is considered to work in a two-step mechanism, involving both vitreoretinal separation and vitreous liquefaction. Furthermore, IMH judgment and prognosis indicators like ellipsoid zone, macular hole index, hole formation factor, diameter hole index and tractional hole index based on spectral domain optical coherence tomography enriched the assessment of macular hole diameter, depth and shape. How to make full use of new interventions to reduce the incidence of macular hole and obtain a better visual acuity with closed holes is an important direction for future research.
Objective To observe the clinical features of acute zonal occult outer retinopathy (AZOOR).Methods Eighteen patients (18 eyes) with AZOOR were enrolled in this study. All the patients were examined for corrected visual acuity, fundus examination, visual field and electroretinography (ERG). For part of these patients, fluorescein angiography (FFA), optic coherence tomography (OCT), visual evoked potential (VEP) and multifocal ERG (mf-ERG) were performed. Clinical features were observed. Comparative analysis was performed on the electrophysiological results between affected eyes and fellow eyes. The consistency of OCT, visual field and mf-ERG results was investigated.Results The patients included three males and 15 females. All patients were unilateral involved. 16 eyes (88.9%) were myopia, two eyes (11.1%) were emmetropia. 11 eyes (61.1%) have normal fundus; single yellow-white punctuate lesion or old RPE lesion near macular were found in three eyes (16.7%); depigmented zones in temporal retina were found in four eyes (22.2%). All central visual field results were abnormal, but peripheral visual field results were normal. OCT findings included irregularity, absence or breaks of the photoreceptor inner segment/outer segment (IS/OS) junction. Amplitudes of full-field ERG were reduced in the affected eyes (t=3.516，2.689，3.103，3.517，2.999，3.309；P＜0.05), and implicit times were delayed in most responses except for rod response (t=1.023,P=0.306). Amplitudes of P100 wave of visual evoked potential were reduced statistically (t=2.04,P=0.041), but the differences of implicit times between the affected eyes and the fellow eyes were not statistically significant (t=1.687,P=0.092). Amplitude reduction of multifocal ERG existed in all affected eyes. Coincidence was found between results of OCT and mf-ERG. But abnormal zones found by central visual field did not always coincide with those by mf-ERG. Conclusions The majority of patients who develop AZOOR are young women with myopia. Most patients have normal fundus. Central visual field and electrophysiological examinations are always abnormal. Irregularity, absence or breaks of the photoreceptor IS/OS junction can be proved by OCT.
Objective To observe the changes of retinal nerve fiber layer (RNFL) thickness and its correlation with visual field mean defects（MD）in Parkinsonprime;s disease (PD).Methods Fifteen eyes of 15 PD patients in early stage and 18 eyes of 18 normal controls undertook RNFL examination by Stratus OCT3. Circular scans (diameter is 3.46 mm) were taken around the optic nerve head including eight quadrants (superior, inferior, temporal, nasal, temporalsuperior, temporalinferior, nasalsuperior and nasalinferior). The RNFL thickness in different quadrants in the two groups was analyzed. The visual field of PD patients was measured by central 302 program of Humphery750 visual field analyzer, and the MD was recorded. The correlation between RNFL thickness and MD was analyzed by linear correlation and regression analysis.Results RNFL thicknesses of superior, inferior, temporal, nasal, temporalsuperior, temporalinferior, nasalsuperior, nasalinferior and average RNFL thickness in the control group were (132.7plusmn;17.4), (141.5plusmn;15.3) ,（83.2plusmn;17.5）, (83.7plusmn;22.3) ,（120.8plusmn;21.2）, (117.9plusmn;24.5) ,（109.6plusmn;20.6）,（110.2plusmn;27.7）, and（109.9plusmn;8.5）mu;m respectively, while in the PD group they were (128.1plusmn;25.3) , (128.6plusmn;13.2) , (68.7plusmn;13.5) , (76.5plusmn;17.8) ,（102.6plusmn;23.7）, (103.3plusmn;14.1) ,（101.2plusmn;20.9）,（96.6plusmn;15.0）,（102.3plusmn;11.9） mu;m. Compared with each other, the differences of RNFL thickness of inferior, temporal, temporalsuperior, temporalinferior and average RNFL thickness were statistically significant（t=2.595，2.700，2.330，2.153，2.131；P=0.014，0.011，0.026，0.040，0.041）. There was a close negative relationship between average RNFL thickness and MD in PD patients (r=-0.933，P＜0.0001). Conclusions RNFL thickness was significantly thinner in PD patients than that in the normal controls. There was a negative relationship between RNFL thickness and MD in PD patients.
Objective To observe the retinal and choroidal changes in morphology and thickness after photodynamic therapy(PDT) for idiopathic choroidal neovascularization(ICNV). Methods Sixteen eyes of 16 patients with ICNV were treated with verteporfin PDT. 16 eyes of 16 agematched normal subjects were observed for the purpose of comparison. The best corrected visual acuity(BCVA) was checked before and 1, 3 and 6 months after PDT treatment. Enhanced depth imaging optical coherence tomography (EDI-OCT) technique was used to measure central retinal thickness (CRT) and central choroidal thickness(CCT). The correlations between BCVA and CRT, CCT were analyzed by Pearson statistical anallyses. Results BCVA was improved at 1, 3 and 6 months after PDT, and the difference had statistical significance compared with that before treatment (F=3.08,P=0.030). There was edema in the retina at 1 month after PDT. CNV in 13 eyes became fibrotic at 3 months after PDT, and all became fibrotic at 6 months after PDT. The reflex of choroid correspond to CNV was weak at 1, 3 and 6 months after PDT. CRT decreased at 1, 3 and 6 months after PDT (F=8.946,P=0.000). The difference was statistically significant between the CRT of control group and that 1 months after PDT (P=0.001), but there was no statistically significant difference between the CRT of control group and that 3 and 6 months after PDT（P=0.128, 0.083）. The CCT group had no statistically significant difference before and 1, 3 and 6 months after PDT (F=1.674, P=0.170). The CCT group also had no statistically significant differences between the control group and 1, 3 and 6 months after PDT (P=0.186, 0.551, 0.98). The BCVA was inversely correlated with CRT and CCT, and the correlation had no statistical significance (r=－0.051,－0.164;P=0.739,0.283). Conclusions PDT may improve BCVA in ICNV. Retinal edema resolves, CRT decreases, but CCT had almost no changes after PDT.
Objective To measure the changes of eye shape and axial length of the eyeball before and after removing the scleral encircling buckles.Methods This is a prospective and controlled study. Twenty eyes (20 patients) with rhegmatogenous retinal detachment and the fellow eyes were enrolled in this study. All patients underwent scleral encircling buckling, and the buckles were removed 2.0-3.5 years after the surgery. The eye shape and axial length of both eyes were measured by three-dimensional computed tomography (3D-CT) before and one,three,six months after the removing surgery. The axial length was also measured by intraocular lens (IOL) Master.Results 3D-CT showed that buckled eyeball depressed at the equator, resulting in a gourd-shaped eyeball. One month after removing the encircling buckle the depression disappeared. By 3D-CT scanning, the axial lengths of buckled eyes were (27.65plusmn;1.22), (27.3plusmn;1.56), (27.29plusmn;1.46) and (27.12plusmn;1.49) mm before and one, three, six months after the removing surgery respectively. The difference between before and after removing surgery was not statistically significant (t=2.89,P=0.723). By IOLMaster, the axial length of operated eyes were (28.32plusmn;1.94), (28.17plusmn;1.87), (28.21plusmn;1.94), (28.25plusmn;1.93） mm respectively. The difference between before and after removing the encircling band was not statistically significant (t=3.304, P=0.93). There was no significant difference in these two measuring modes (t=3.705,P=0.847).Conclusions Encircling buckling can cause eyeball indentation, removing the encircling band can rescue the indentation. There are no changes in the axial length before and after removing the encircling buckles.
The improvement of diagnostic levels for fundus diseases depend on the advancements of fundus imaging technology. Different fundus imaging technologies allow doctors to inspect ocular fundus from different aspects such as morphological or functional changes of retina. As a basic fundus examination method, optical coherence tomography provides highresolution and crosssectional retinal images coupled with noninvasive advantages. Fully understanding of the advantages and disadvantages of each fundus imaging technique, appropriate choosing one or combining several imaging techniques, and optimizing diagnostic procedures for each fundus disease are crucial steps to improve our diagnostic levels of ocular fundus diseases.
Objective To observe the characteristics of fundus fluorescein angiography（FFA）and optical coherence tomography（OCT）in nonarteritic anterior ischemic optic neuropathy (NAION),and investigate its relation with visual acuity and course of disease.Methods The clinical data of 47 patients (47 eyes) with NAION were retrospectively analyzed. All the patiens had undergone visual acuity，fundus and visual field examination，meanwhile FFA and OCT were carried out at first visit. FFA and visual field were carried out by routine. OCT was carried out by line and circle shape scanning in macula and optic disc. Thirtyfive NAION patients were checked with OCT at half, one, two, three and six month after onset in respectively. Take the healthy fellow eyes of 36 NAION patiens as control group.The FFA,visual field,OCT characteristics and relation with visual acuity and course disease were comparatively analyzed.ResultsFFA showed that all the eyes appear as delayed filling of the optic disc in early stage and hyperfluorescence leakage of the optic disc in late stage，besides hyperfluorescence presented to macular area in 24 eyes. OCT showed that optic papilla swelling and physiological depression narrow or nearly disappearance, neuroepithelial layer thickening or neuroepithelial layer eminence and subretinal fluidity area opaca between optic disc and macula. There were 14 eyes with normal physiological depression and 22 eyes with small physiological depression or non physiological depression in control group. Half month after onset，the neuroepithelial layer thickness of macula fovea, the maximum thickness of neuroepithelial layer between optic disc and macula，and the average retinal nerve fiber layer（RNFL）thickness in NAION group were higher than those in the control group，the difference were statistically significant (F=6.51，26.12，75.49；P＜0.05).Two months after onset，the maximum thickness of neuroepithelial layer between optic disc and macula, the average RNFL thickness, and the RNFL thickness of temporal optic disc in NAION group were significant thinner, but the elevated height of the optic disc in NAION group were near those of the control group. Three months after onset，the average RNFL thickness and the RNFL thickness of temporal optic disc in NAION group decreased continually, they were lower than those of the control group, the difference were statistically significan（F=75.49，37.92；P＜0.05）.Visual field showed that inferior defect were found in 21 eyes (45%). With progress, the superior RNFL thickness obviously decreased, coincidence with appearance of visual field. It indicate that the superior optic atrophy serious. Visual acuity had significant negative correlation with the neuroepithelial layer thickness of macula fovea, the neuroepithelial layer maximum thickness between optic disc and macula, the average RNFL thickness, the RNFL thickness of temporal optic disc(r=-0.394,-0.424,-0.412,-0.464；P＜0.05).Conclusions FFA showes that hyperfluorescence leakage appearanced in part macula. OCT showes that RNFL becomes thinner as the disease duration increases. The results of OCT and visual field examinaion in the configuration of optic disc and changes of RNFL are accordant.