Objective To observe the diameters of macular hole and destroyed boundary line between inner and outer segment (IS/OS) of the photoreceptors and the correlation with the visual acuity in patients with idiopathic macular hole(IMH). Methods The clinical data of 39 eyes (37 patients) with IMH were retrospective analyzed. All the patients had undergone the examinations of visual acuity (Snellen chart), intra-acular pressure, ocular fundus (indirect ophthalmoscope), and Fourier-domain optical coherence tomography (FD-OCT) whose speed was 27 000A scan/s, area was 6.0 mmtimes;6.0 mm, and the mode was 512times;128. The diametres of macular hole and destroyed IS/OS, and the correlations with visual acuity were detected. Results The mean logMAR was 0.99plusmn;0.44 (ranged from 0.15 to 2.00),the mean diameter of macular holes was (942.0plusmn;348.4) mu;m(ranged from 171 to 1491 mu;m), and the mean diameter of IS/OS disruption was (1870.3plusmn;673.2) mu;m(range from 463 to 3176 mu;m). There was a significant correlation among the diameter of the macular hole, the diameter of the IS/OS disruption, and logMAR in IMH (P＝0.038, 0.002, 0.000）. In eyes with closed macular hole after surgery, the logMAR and the diameter of the IS/OS disruption had a significant decrease. Conclusion Using FD-OCT the photoreceptor changes can be visualized in vivo. The abnormality in the ISOS boundary line appears to be involved for a much larger area beyond the macular hole itself, and persists there with small size even after the macular hole closure surgery.
ObjectiveTo observe the pathological changes of central retinal artery occlusion (CRAO) by optical coherence tomography (OCT).MethodsFifty-three eyes of 53 patients who were diagnosed as CRAO in our center between January 2001 to January 2004 underwent the examination by OCT. The intervals between the disease onset and OCT examination were less than 2 weeks. The scan modes of OCT were horizontal or vertical line scan. The locations of scanning were macular, posterior pole of retina, optical papilla and the focus of bleeding or exudation.ResultsThe OCT pathological changes of CRAO in vivo includes increase of retinal thickness and reflex of retina, width of dark layer of photoreceptor (edema), edema or cystoid edema of fovea, retinal bleeding, cotton-wool spot and papilla edema. Four patients who had ciliary retinal artery showed normal retinal structure in the supply region of ciliary retinal artery.ConclusionOCT can display the pathological changes of retinal tissues in CRAO in vivo, especially on the old patients or the patients with systemic disease who were contraindicated by FFA. The unique OCT image of pathological changes of CRAO supply the objective signs for the instant clinical diagnosis.(Chin J Ocul Fundus Dis, 2005,21:74-78)
Objective To investigate the characteristics of optical coherence tomography (OCT) images in idiopathic macular hole. Methods OCT、color photography and fundus fluorescein angiography were performed in 65 cases(70 eyes) of macular holes and which were then graded by connecting to their clinical characteristics. Results Among the 70 eyes the number of 1～4 stages of macular holes were 11,12,36 and 11 eyes respectively.In eyes of stage 1 OCT images showed flattening or disappearing of fovea and minimally reflective space within or beneath the neurosensory retina;stage 2 showed a fullthickness hole with an attached operculum and surrounding edema;stage 3 displayed a full-thickness hole with surrounding edema and stage 4 showed a full-thickness hole and a complete separation of the poterior hyaloid membrane from the retina.The dimeter of the macular holes in stage 2,3 and 4 were (241.75plusmn;107.08),(699.78plusmn;160.99), (631.36plusmn;243.46)mu;m,respectively. Conclusions OCT can display the characteristics of idiopathic macular holes and measure the diameters of holes quantitatively. (Chin J Ocul Fundus Dis, 1999, 15: 205-208)
Objective To observe the Fourierdomain optical coherence tomography（FD-OCT）characteristic of idiopathic epiretinal membrane (ERM) and its correlation with the patients visual acuity. Methods The 116 eyes (112 patients) with idiopathic epiretinal membrane were included in this study. All the patients had undergone examination of visual acuity (LogMAR chart), ocular fundus (direct ophthalmoscope and fundus pre-set lens), and FD-OCT (Zeiss HD-OCT) with the speed of 27 000 A scan/s,area of 6.0 mmtimes;6.0 mm, and mode of 512times;128. The central fovea thickness (CFT), volume (V), average thickness (AT) were collected from the OCT readings, and the fovea thickness (FT) was measured manually. Data were analyzed using SPSS 16.0. Results The traction on retina caused by ERM can be divided into 3 types according to the OCT findings: no traction (9.48%), tangential traction (84.48%) and tangential traction with anteriorposterior traction (6.04%). A total of 97 eyes (83.62%) had retinal edema (diffuse or cystoid) and the edema located at the outer nuclear layer(ONL), outer plexiform layer(OPL)and inner nuclear layer (INL) . A total of 14 eyes (12.07%) had retinal nerve fiber layer (RNFL) schisis and 27 eyes (23.28%) had inner segment/outer segment junction (IS/OS) impairment. Statistic analysis revealed that BCVA was not related to the age, gender, types of traction, presence of IS/OS damage or RNFL schisis (Pgt;0.05), but was related with CFT(Plt;0.05). Conclusions Idiopathic ERM can exert different types of traction on the macular, and cause different types of retinal lesions. OCT is a useful tool to measure these lesions. CFT reading is closely related to patients' visual acuity.
ObjectiveTo evaluate Micron Ⅳ retinal imaging system in three mouse models of retinal diseases. MethodsMouse models of oxygen induced retinopathy (OIR) model (OIR group), N-methyl-N nitrosourea (MNU) model (MNU group) and N-methyl-D-aspartate (NMDA) model (NMDA group) were induced in 24 healthy male C57BL/6J mice. Fundus photograph, fundus fluorescein angiography (FFA) and optical coherence tomography (OCT) and electroretinogram (ERG) were used to evaluate these mice. All the imaging examinations were performed by Micron Ⅳ retinal imaging system. ResultsOIR mice showed tortuous and dilated retinal vessels in fundus photograph, neovascularization plexus and vascular leakage in FFA, and epiretinal fibrovascular tissue and tortuous expansion vascular vessels in OCT. MNU mice showed wax yellow optic disk without retinal pigmentary changes, slight thinning of retinal blood vessels in FFA, and normal structure and thickness in OCT. The a-wave amplitudes of the maximum mixed response decreased significantly, and were (15.38±4.36) μV and (13.78±5.52) μV at 2 or 3 days of modeling, respectively. NMDA mice showed a pale retina with vasospasm. ERG revealed that there was no obvious change in latency of a- and b-wave, but significantly decreased amplitude of b-wave at 12 hours and 24 hours after modeling with (72.28±7.18) μV and (65.35±9.18) μV, respectively. ConclusionMicron Ⅳ retinal imaging system is a real-time, non-invasive tool to study the retinal structure and function in animal models of retinal diseases.
Objective To observe the effects of local macular foveal photoreceptor defects on visual acuity.Methods Thirty-one patients (31 eyes) with photoreceptor defect in macular fovea (case group) diagnosed by spectral domain optical coherence tomography (SD-OCT) and 30 patients (30 eyes) age- and diopter- matched normal subjects (control group) were enrolled in this study. There were 22 eyes with full photoreceptor defects and 9 eyes with outer segment defects in case group. All subjects were examined for best corrected visual acuity (BCVA), slit-lamp microscopy, direct ophthalmoscope and SD-OCT. Independent sample t-test was used to compare central foveal thickness (CFT) between case group and control group. Difference of logMAR BCVA, CFT, maximum width and height of photoreceptor defects, defected area and residual retinal thickness in macular between patients with full photoreceptor defects and outer segment defects were also compared.Results The CFT of case group and control group were (225.32plusmn;19.70),(240.02plusmn;10.70) mu;m, the difference was not statistically significant (t=-1.96, P＞0.05). In full photoreceptor defects and outer segment defects patients, the mean logMAR BCVA were 0.22plusmn;0.31, 0.32plusmn;0.43; the mean CFT were (224.09plusmn;20.57), (228.33plusmn;18.17) mu;m; the maximum width of photoreceptor defects were (131.32plusmn;108.18), (143.22plusmn;66.93) mu;m; the mean defected area were (0.022plusmn;0.054), (0.019plusmn;0.019) mm2; the mean maximum height of photoreceptor defects were (77.41plusmn;6.62), (44.89plusmn;4.26) mu;m; the mean residual retinal thickness were (87.00plusmn;20.31), (128.33plusmn;23.54) mu;m respectively. There was no statistical significance between full photoreceptor defects and outer segment defects patients in the mean logMAR BCVA, CFT, maximum width of photoreceptor defects and defected area (t=-0.76, -0.538, -0.305, 0.166; P＞0.05), but there were significant difference in mean maximum width of photoreceptor defects and residual retinal thickness (t=12.72, -4.91;P＜0.05). Conclusions The local photoreceptor defects in macular fovea can lead to decrease of visual acuity. The wider the photoreceptor defects, the worse the visual acuity.
Objective To observe the imaging features of ultra-wide field short wave fundus autofluorescence (SW-FAF) in eyes with multiple evanescent white dot syndrome (MEWDS), and analysis the correspondence to conventional images. Methods It was a retrospective case series study. Thirteen patients (14 eyes) diagnosed with MEWDS were enrolled. There were 12 females and 1 male, aged from 22 to 57 years, mean age was 34.5 years. All the eyes underwent fundus color photography, optical coherence tomography (OCT) and ultra-wide field autofluorescence (FAF). Simultaneous fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed in 6 eyes. The characteristic changes of SW-FAF in studied eyes were observed and compared with the images of FFA and ICGA. All the eyes were followed up every 1 to 2 weeks, with an average of 16.7 weeks. The characteristic images of SW-FAF and corresponding OCT were studied during follow up. Results MEWDS presented with numerous multiple hyper-autofluorescent spots, sized from 50-500 μm, with a vague boundary in ultra-wide field SW-FAF. These spots located mainly at the peripapillary area and the posterior pole with a confluent pattern. The lesions extended to the mid-peripheral retina as well and became more scattered. The distribution of the hyper-autofluorescent lesions in SW-FAF corresponded roughly to that of the greyish-white spots seen in color photograph and the hyper-fluorescent spots detected by FFA. It was consistent with the distribution of hypo-fluorescent spots in late-phase ICGA as well. But the number of the spot showed in FAF is much more than that in FFA, and slightly less than that in ICGA. The OCT scans through the hyper-autofluorescent lesions in SW-FAF showed impairment of outer retina. After the recovery, the hyper-autofluorescent spots disappeared with the outer retina structure repaired completely. Conclusions MEWDS presented with numerous multiple hyper-autofluorescent spots which located mainly at the peripapillary area in ultra-wide field SW-FAF. The distribution of the hyper-autofluorescent lesions in SW-FAF corresponded roughly to color photograph, FFA and ICGA in late-phase. The OCT scans through the hyper-autofluorescent lesions in SW-FAF showed impairment of outer retina.
Ophthalmic imaging including radiographic imaging, acoustic imaging and optical imaging, as a branch of medical imaging has developed rapidly. Optical imaging is very suitable for fundus examination because of the physiological characteristics of the eye. Ophthalmoscope and fundus fluorescein angiography are two historical stages of fundus optical imaging, which become an independent new discipline now, including infrared fundus photography, fundus autofluorescence, fundus fluorescein and indocyanine green angiography and optical coherence tomography. Comprehensive optical imaging plays an irreplaceable role in the diagnosis and treatment evaluation of ocular fundus diseases. Appropriate understanding the principles and significance of various optical imaging methods is very important for their clinical applications.
ObjectiveTo observe the morphologic characteristics of drusen in atrophic age-related macular degeneration (AMD) by spectral domain optical coherence tomography (SD-OCT). MethodsFifty-four patients (84 eyes) with macular drusen and atrophic AMD, and 56 age-matched control patients (56 eyes) with cataract were included in this study. Atrophic AMD patients were divided into two groups: D1 group with drusen involving the fovea (42 eyes) and D2 group with drusen not involving the fovea (42 eyes). The SD-OCT images in macular (6 mm×6 mm scans) were acquired, and the foveal retinal thickness (FRT) was measured. The size, morphology, inner reflection, homogeneity of drusen and its relationship with surrounding tissues were analyzed. ResultsThe FRT of D1 group, D2 group and control group were (160.90±38.47), (194.21±26.11), (222.42±19.29) μm respectively. The FRT of D1 group and D2 group were thinner than that of control group (F=57.08, P=0.00). Totally 1124 drusen were found by SD-OCT images in 84 eyes, with an average of 10.84 drusen in each eye. 3.0%, 12.5% and 84.5% of all 1124 drusen were small, medium and large sized respectively. 56.6%, 14.2%, 20.4% and 8.8% of all drusen were dome, pointed, saw-toothed and basal-shaped respectively. 17.1%, 57.5% and 25.4% of all drusen had low, medium and high internal reflectivity respectively. The internal reflectivity of 65.6%, 2.8% and 31.7% of all drusen were homogeneous, nonhomogeneous with core, and nonhomogeneous without core respectively. Overlying retinal pigment epithelium (RPE) damage and photoreceptor inner segment/outer segment (IS/OS) junction damage were presented in 34.5% and 24.8% drusen respectively. The most common type of drusen was dome-shape, homogeneous, with medium internal reflectivity, and without overlying RPE or IS/OS junction damage (81.0%). ConclusionsThe FRT becomes thinner in patients with drusen. The most common drusen types are dome-shaped, homogeneous, with medium internal reflectivity, and without overlying RPE or IS/OS junction damage.
Objective To analyze the clinical presentations and radiological characteristics of acute exacerbation of idiopathic pulmonary fibrosis ( IPF) . Methods Clinical and radiological data of 2 patients with acute exacerbation of IPF from April 2006 to July 2008 were retrospectively analyzed and literatures were reviewed. Results Both patients were senior male patients over 60 years old. Dyspnea, cough and inspiratory crackles were the major symptoms and signs. Two patients were experiencing an exacerbation of dyspnea for one week and half of month, respectively. PaO2 /FiO2 of both patients was less than225 mm Hg. In both patients, high-resolution computed tomography ( HRCT) scans at the exacerbation showed typical signs of IPF including peripheral predominant, basal predominant reticular abnormality, with honeycombing and traction bronchiectasis and bronchiolectasis, and newly developing alveolar opacity. HRCT scan showed peripheral area of ground-glass attenuation adjacent to subpleural honeycombing in one patient, and diffusely distributed ground-glass opacity in another patient. Two patients had received corticosteroid treatment. For one patient, the symptoms improved, and ground-glass attenuation adjacent to subpleural honeycombing had almostly resolved. The other patient died of respiratory failure. Conclusions Some acute exacerbation in idiopatic pulmonary fibrosis can be idiopathic. The clinical presentations mainly include the worsening of dyspnea within short time. HRCT generally demonstrates new bilateral ground-glass abnormality with or without areas of consolidation, superimposed on typical changes of IPF.