The status and advances in the application of optical coherence tomography and optical coherence tomography angiography in non-arteritic ischemic optic neuropathy / 中华眼底病杂志

Non-arteritic ischemic optic neuropathy (NAION) is a neurological disease due to poor perfusion in optic disk. It causes severe visual function impairment, characterized by loss of vision and visual field defect. Optical coherence tomography (OCT) is vital for detecting anterior laminar depth, peripapillary nerve fiber layer thickness, ganglion cell complex thickness and peripapillary choroid thickness change in eyes with NAION at different course of the disease. In addition, OCT features are in accordance with visual function impairment. OCT angiography (OCTA) reveals retinal and choroidal vasculature networks in optic and macular area. OCTA revealed vasculature perfusion decline in eyes with NAION, even if their visual sensitivity and visual evoked potential were normal. Studying OCT and OCTA features is vital for exploring the pathogenesis and prognosis of NAION.

Diagnostic value of thickness of macular ganglion cell complex and retinal nerve fiber layer measured by optical coherence tomography in patients with anterior ischemic optic neuropathy / 中华实验眼科杂志

Background Anterior ischemic optic neuropathy (AION) is a common eye disease,and early diagnosis is very important for reserving useful vision.Frequency-domain optical coherence tomography (FD-OCT) can display retinal microstructure in vivo and quantify the thickness of macular ganglion cell complex (GCC) and retinal nerve fiber layer (RNFL).Previous study on assessing retinal ganglion cell loss is assessed by measuring the RNFL thickness,while recent researches showed that GCC thickness measurement can reveal the retinal structure change in AION patients.However,there is few comparative studies on the diagnostic efficiency of RNFL thickness versus GCC thickness for AION.Objective This study was to evaluate and analyze the diagnostic value of GCC thickness and RNFL thickness measured by FD-OCT in patients with AION.Methods Fifteen eyes of 15 patients with AION and 14 normal eyes of 14 normal persons were enrolled in Eye Hospital of Tianjin Medical University from December 2013 to July 2014.Macular GCC thickness and disc RNFL thickness were measured by FD-OCT,and macular GCC thickness included superior,inferior and average GCC thickness around 6 mm×6 mm of macula,and focal loss volume (FLV) and global loss volume (GLV) were calculated.The disc RNFL thickness included superior,inferior and mean RNFL thickness around disc.The measuring outcomes between AION group and normal control group were compared.The diagnostic efficiency of GCC thickness and RNFL thickness was evaluated by the area under the receiver operating characteristic (ROC) curve.Results Compared with normal control group,the GCC thickness at superior,inferior and average GCC thickness at macula were thinner,with significant differences between them (t=-3.402,P=0.002;t =2.690,P=0.012;t=2.913,P=0.007).The FLV and GLV values were (8.39±4.54) μm3and (19.57±10.66) μm3 in the AION group,which were significantly lower than (0.64±0.48) μm3 and (1.14±0.91) μm3 in the normal control group (t=5.036,6.732;both at P＜0.01).The disc RNFL thicknesses of superior,inferior and average RNFL were thinner in the AION group than those in the normal control group,with significant differences between them (t=2.815,P=0.009;t =2.392,P=0.024;t =2.863,P=0.008).The AUC of FLV and GLV for AION were both 1.000,and that of superior GCC thickness,inferior GCC thickness and average GCC thickness at macula was 0.871,0.819 and 0.795,respectively.The AUC of average RNFL thickness and disc superior,inferior RNFL thicknesses for AION were 0.814,0.809 and 0.762,respectively.Conclusions The diagnosis ability of GCC and RNFL thickness for AION is comparable.FLV and GLV appear to have the strongest efficiency in the evaluation of GCL in AION patients.Macular GCC measurement may provide a good alternative or a complementary practice to RNFL scans for the diagnosis of AION.

Nonarteritic anterior ischemic optic neuropathy following pars plana vitrectomy for macular hole treatment: case report / Neuropatia óptica isquêmica anterior não arterítica pós vitrectomia pars plana para tratamento do buraco macular: relato de caso

ABSTRACT Herein, we report a case of nonarteritic anterior ischemic optic neuropathy (NAION) following uneventful pars plana vitrectomy for macular hole treatment. A 56-year-old previously healthy woman presented with a full-thickness macular hole in right eye (OD) and small cup-to-disc ratios in both eyes. Five days after surgery, she noticed sudden painless loss of vision in OD and was found to have an afferent pupillary defect and intraocular pressure of 29 mmHg. Fundus examination showed right optic disc edema and the resolution of a macular hole with an inferior altitudinal visual field defect. Erythrocyte sedimentation rate, C-reactive protein levels, and general physical examination findings were normal. She was treated with hypotensive eyedrops and oral prednisone, resulting in mild visual improvement and a pale optic disc. A combination of face-down position and increased intraocular pressure due to a small optic disc cup were considered as potential mechanisms underlying NAION in the present case. Vitreoretinal surgeons should be aware of NAION as a potentially serious complication and be able to recognize associated risk factors and clinical findings.

RESUMO Nosso objetivo é descrever a ocorrência de neuropatia óptica isquêmica anterior não-arterítica (NOIA-NA) após vitrectomia posterior para tratamento do buraco macular. Uma mulher de 56 anos de idade previamente hígida apresentou buraco macular de espessura total no olho direito (OD) e uma relação escavação disco pequena em ambos os olhos. No quinto dia de pós-operatório ela notou uma perda visual súbita e indolor OD associado a presença de um defeito pupilar aferente relativo e pressão intraocular de 29 mmHg neste mesmo olho. A avaliação do fundo de olho revelou a presença de edema de disco óptico e buraco macular fechado OD associado a presença de defeito de campo visual altitudinal inferior. A velocidade de hemossedimentação e a dosagem da proteína C reativa foram normais, assim como o exame físico geral. A paciente foi tratada com colírios hipotensores e prednisona oral e evoluiu com discreta melhora visual e palidez de disco óptico. Acreditamos que a combinação de posição de cabeça virada para baixo associado a um aumento da pressão intraocular em um paciente com relação escavação disco pequena são os possíveis mecanismos para a ocorrência de NOIA-NA neste presente caso. Os cirurgiões de retina e vítreo devem estar atentos a esta possível grave complicação e reconhecer os seus fatores de risco relacionados assim como sua apresentação clinica.

Optical coherence tomography angiography in anterior ischemic optic neuropathy / 中华眼底病杂志

Objective To observe the optic disc perfusion in anterior ischemic optic neuropathy (AION) patients.Methods Forty eyes of 40 AION patients and 30 eyes of 30 normal subjects were included.The stage of the diseases was defined based on the course of the disease,including acute stage (less than 3 weeks) and recovery stage (more than 3 months).Optic disc blood flow area,outer vascular density and blood flow index were measured by optical coherence tomography angiography in all the subjects.Optic disc perfusion was observed in acute and recovery stage of disease.Results The optic disc blood flow area,outer vascular density and blood flow index were decreased of AION eyes in acute stage compared with the normal subjects,the difference was statistically significant (P＜0.05);while the optic disc blood flow area,outer vascular density and blood flow index of AION eyes in the recovery stage showed no significant difference compared with normal subjects (P＞0.05).Conclusion Disc perfusion is reduced in AION at the acute stage,but recovered at the recovery stage.

Characteristics of multifocal eletrotetinogram in nonarteritic anterior ischemic optic neuropathy and its relationship with visual acuity and macular central retinal thickness / 中华眼底病杂志

Objective To observe the characteristics of multifocal eletrotetinogram (mfERG) in nonarteritic anterior ischemic optic neuropathy (NAION) and its relationship with visual acuity and macular central retinal thickness (CRT).Methods By means of patients self-contrast analysis.40 patients (40 eyes) with NAION were collected underwent the examinations of best corrected visual acuity, fundus color photography, fundus fluorescein angiography and field of vision.All the disease and normal eyes had underwent the examination of frequency-domain optical coherence tomography (fdOCT) and mfERG.The CRT and retinal thickness about perifovea, parafovea were documented with fdOCT.All patients underwent the retinal macular function exam with mfERG.Centered by macular fovea, the reaction zone were divided into 5 rings from inside to outside by circles, ring 1 0.00°, ring 2 5.44°, ring 3 10.31°, ring 4 16.31°, ring 5 23.42°.Treated ring 1 hexagon as macular center the amplitude densities of P1 wave, the amplitude of P1 and N1 wave, and the latencies of P1and N1 wave at cvcry ring were observed.The relationship between mfERG characteristics and visual acuity or CRT were analyzed by Spearman correlation analysis.Results fdOCT revealed that there was significantly statistical difference in the retinal thickness about perifovea between disease eyes and contralateral eyes (P＜＜0.05).The increase of CRT and retinal thickness about parafovea had no significantly statistical difference between diseases eyes and contralateral eyes (P＞0.05).mfERG revealed that the decrease of amplitude densities about P1 wave at ring 1 to 2 had significantly statistical difference between two groups (P＜0.05);there were no significantly statistical difference in the amplitude densities of P1 wave at ring 3 to 5;the decrease of amplitude about P1 and N1 wave at ring 1 had significantly statistical difference between two groups (P ＜ 0.05).There was no significantly statistical difference in the amplitude of P1 and N1wave at ring 2 to 5, the latencies of P1 and N1 wave at ring 1 to 5 (P＞0.05).The correlation analysis revealed that the amplitude densities and amplitude of P1 wave at ring 1, amplitude of N1 wave at ring 1 had no effect on visual acuity (r=0.087,0.195,-0.134;P＞0.05) and CRT(r=-0.154,0.365, 0.412;P＞0.05).Conclusions Compared with contralateral eyes,the disease eyes were significantly decrease in amplitude densities of P1 wave at ring 1 to 2, amplitude of P1 and N1 wave at ring 1.There are no correlated between the amplitude densities of P1 wave at ring 1,amplitude of P1 and N1 wave at ring 1 and visual acuity or CRT.

Diagnosis and treatment of non-arteritic anterior ischemic optic neuropathy / 中华眼底病杂志

The characteristics of non-arteritic anterior ischemic optic neuropathy (NAION) include sudden decline of visual acuity, sector-shaped visual field defect connected with the physiological blind spot or hemi-visual field defect, and optic disc edema. Early angiographic abnormalities of optic disc and peripapillary choroidal circulation are important cues for the diagnosis. Angiography combined with visual field test can make the diagnosis more accurate. The pathological mechanism and process of NAION and ischemic cardiovascular/cerebrovascular disease are essentially the same. There are several critical issues in this field we need focus on, including strengthening the cooperation with relevant professional disciplines; improving the ocular ischemia through drugs, intervention and other means; preventing more serious cardiovascular events and intervening in a number of high-risk populations to reduce the incidence of AION.