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.
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.