Microperimetry and spectral domain optical coherence tomography in myelinated retinal nerve fibers

Dear Sir,I write to present the correlation between microperimetric （MP） values and the density of myelinated retinal nerve fibers （MNFs） in optical coherence tomography （OCT） imaging.

Retinal Functional Changes Measured by Microperimetry after Intravitreal Ranibizumab Injection and Sulfotanshinone Sodium Injection for Macular Edema Secondary to Retinal Vein Occlusion

Objectives: To study the visual field changes after intravitreal ranibizumab (IVR) injection and sulfotanshinone sodium (SS) injection for macular edema (ME) secondary to retinal vein occlusion (RVO), and discuss the value of microperimetry as a routine diagnostic test in the follow-up of RVO patients. Methods: This was a retrospective, interventional, case-series study. Twelve eyes of 12 RVO patients, including 6 eyes with central RVO (CRVO) and 6 eyes with branch RVO (BRVO) were included. The eyes were treated with IVR (0.5 mg) injections and SS injections (20 mg per day, one week consecutively in one month). The outcomes measured included best corrected visual acuity (BCVA), central retinal thickness (CRT), mean defect (MD), pattern standard deviation (PSD), macular light sensitivity of the central 16 points in CRVO group and the central 8 points in BRVO group before and after the treatment. Statistical analyses were then performed on the main outcome measures. Results: An improvement of BCVA was found in all patients after treatment with significant difference (t = 7.74, p p p p > 0.05). All RVO patients had their macular light sensitivity of the involved part improved significantly (t = 5.03, p p p < 0.01). The Pearson’s correlation was calculated among BCVA, MD, macular light sensitivity and CRT. No obvious significance was found between CRT and BCVA outcomes, whereas MD and mean macular light sensitivity outcomes were closely related to BCVA results in the BRVO group and the latter showed a more intimate correlation. No similar correlation was found in RVO and CRVO group. Conclusion: IVR injection and SS injection together could effectively improve the therapeutic effect in RVO patients with ME. Microperimetry could be used as a routine diagnostic test and a possible valuable tool in the follow-up of patients with RVO, especially in BRVO.

Central Retinal Microperimetry by Scanning Laser Ophthalmoscopy in Chiasmal Patients with Visual Inattention Temporally at Monocular Visual Acuity Testing

Background: In a previous study, a specific visual behaviour was described in four chiasmal patients. It manifested as inattention/ignorance within the temporal visual space (“visual blocking”) at monocular visual acuity testing. Moreover, in 3 out of the 4, the process of reading a text appeared cognitively impaired. Methods: As a supplement to conventional visual field testing, the present analysis focus was on microperimetry by Scanning Laser Ophthalmocopy (SLO). Our aim was to identify the perceptual retinal counterparts to the temporally located visual field defects as caused by the visual pathway lesion on a chiasmal level, possibly also to indicate the apparently ineffective saccadic movements underlying that only part of the line on the chart could be given. Results and Conclusions: The central retinal areas with lacking recognition by SLO testing were given by black rectangles expressing scotomatous points;they clustered in a zone extending nasally from the fixation area, as expected. The methodology further depicted an orderly fixation in two cases, and only minor deviation in two. Fixation saccades thus were considered by and large within normal and with only exceptional outlier points recorded. All considered, the shortcomings of the perceptual mechanisms underlying the lateralised visual inattention as observed in the four patients have remained without a satisfactory explanation.

MP-3 microperimeter in early primary open angle glaucoma with a new pattern

AIM:To investigate macular microperimetry in patients with early primary open angle glaucoma(POAG)using a new custom-made pattern,and analyze the characteristics of macular sensitivity.METHODS:This case-control study included 38 patients with POAG,who were divided into pre-perimetric glaucoma(18 eyes of 18 patients),early-stage(20 eyes of 20 patients),and control(20 eyes of 20 patients)groups.All subjects underwent standard 24-2 humphrey visual field test.An MP-3 microperimeter with a new custom-made pattern(28 testing points distributed in four quadrants,covering the central 10°of the retina)was used to evaluate macular sensitivity.Ganglion cell complex(GCC)thicknesses were examined using an RS-3000 Advance OCT system.The features of structure and function were analysed per quadrant.RESULTS:The pre-perimetric glaucoma group had significantly lower inferior hemifield macular sensitivity compared to controls(P<0.05).The early-stage POAG group had significantly lower average,inferior hemifield,inferonasal,and inferotemporal mean sensitivities compared to the pre-perimetric glaucoma group(P<0.05),and lower macular sensitivity in all sectors compared to controls(P<0.05).Regarding GCC thickness,all sectors in the early-stage POAG group became thinner compared to those in controls(P<0.05);whereas all sectors in the early-stage POAG group,except the superonasal quadrant,became thinner compared to those in the pre-perimetric glaucoma group(P<0.05).Macular sensitivity and GCC thickness were significantly associated in each sector.The inferotemporal quadrant had the highest correlation coefficients(0.840).The structure-function relationship for the inferonasal and inferotemporal sectors was stronger compared to the corresponding superior sectors.CONCLUSION:Microperimetry reveals variations in macular sensitivity in patients with early glaucoma earlier than conventional perimetry,particularly in pre-perimetric glaucoma cases in which it might be undetectable by conventional methods.The new custom-made pattern may improve the accuracy of microperimetry by enhancing point arrangement and reducing fatigue effects.Macular sensitivity measured by MP-3 with this pattern shows statistically significant structural and functional associations with the thicknesses of the GCC.

Efficacy and safety of subthreshold micropulse laser in the treatment of acute central serous chorioretinopathy

·AIM:To analyze the efficacy and safety of subthreshold micropulse laser(SML)in the treatment of acute central serous chorioretinopathy(CSC).·METHODS:This is a retrospective case analysis study.Totally 58 eyes of 58 patients were enrolled,and they were divided into different groups.And 39 patients were treated with SML(SML group)and 19 patients were only observed(observation group).The follow-up period was 3mo after diagnosis.The best corrected visual acuity(BCVA),central retinal thickness(CRT),superficial retinal vascular density(SRVD),deep retinal vascular density(DRVD),the superficial and deep foveal avascular zone(FAZ)area,retinal light sensitivity(RLS),perfusion area of choroidal capillary layer(CCL),subfoveal choroidal thickness(SFCT)and fundus autofluorescence(FAF)were investigated.·RESULTS:The BCVA,CRT,SRVD,DRVD,the superficial and deep FAZ area,RLS,SFCT of SML group were significantly improved at 3mo(all P<0.05).In the observation group,only CRT,DRVD and SFCT were improved(all P<0.05).Other research items in the observation group were not significantly different from baseline(all P>0.05).At the last follow-up,the BCVA and RLS in the SML group were better than those in the observation group,and CRT was lower,SRVD and DRVD,perfusion area of CCL were larger(all P<0.05).On FAF,no change of treatment spots was found after treatment.No structural laser damage was observed on optical coherence tomography(OCT)and optical coherence tomography angiography(OCTA),and no choroidal neovascularization was observed.·CONCLUSION:SML treatment of acute CSC can improve BCVA,RLS,and perfusion area of CCL,reduce CRT,increase SRVD and DRVD,and is safe.

Time in range as a useful marker for evaluating retinal functional changes in diabetic retinopathy patients

·AIM:To elucidate the relationship between macular sensitivity and time in range(TIR)obtained from continuous glucose monitoring(CGM)measures in diabetic patients with or without diabetic retinopathy(DR).·METHODS:This was a cross-sectional study including 100 eyes of non-DR patients and 60 eyes of DR patients.An advanced microperimetry was used to quantitate the retinal mean sensitivity(MS)and fixation stability in central macula.TIR of 3.9-10.0 mmol/L was evaluated with CGM.Pearson coefficient analysis and multiple linear regression analysis were used to assess the correlation between TIR and retinal sensitivity.·RESULTS:In a comparison of non-DR patients,significant differences(P<0.05)were found in Hb A1c,TIR,coefficient of variation(CV),standard deviation of blood glucose(SDBG)and mean amplitude of glucose excursion(MAGE)values in DR patients.Besides,those DR patients had significantly poor best-corrected visual acuity(BCVA,log MAR,P=0.001).In terms of microperimetry parameters,retinal mean sensitivity(MS)and the percentages of fixation points located within 2°and 4°diameter circles were significantly decreased in the DR group(P<0.001,P<0.001,P=0.02,respectively).The bivariate contour ellipse area(BCEA)encompassing 68.2%,95.4%,99.6%of fixation points were all significantly increased in the DR group(P=0.01,P=0.006,P=0.01,respectively).Correlation analysis showed that MS were significantly correlated with Hb A1c(P=0.01).TIR was positively correlated with MS(r=0.23,P=0.01).SDBG was negatively correlated with MS(r=-0.24,P=0.01)but there was no correlation between CV and MAGE with MS(P>0.05).A multivariable linear regression analysis was performed to prove that TIR and SDBG were both independent risk factors for MS reduction in the DR group.·CONCLUSION:TIR is correlated with retinal MS reduction in DR patients,suggesting a useful option for evaluating DR progression.

What is new in central serous chorioretinopathy?

Central serous chorioretinopathy(CSCR) is considered a benign, self-limiting disease. However, as many as third of the patients have recurrent episodes or chronic disease that may cause significant functional impairment. New diagnostic tools and new treatment modalities are emerging in order to improve the functional outcomes of these patients. Spectral domain optical coherence tomography(SD-OCT) has the ability to image individual layers of the retina and choroid. SD-OCT images in CSCR patients have demonstrated increased subfoveal thickness measurements, high reflective deposits in areas of subretinal precipitates and changes in the Retinal pigment epithelium layers of the asymptomatic eyes of patients with supposedly unilateral CSCR. A positive correlation was found between the level of distribution to the layer of inner segment/outer segment junction of the photoreceptors and the visual impairment. Fundus autoflouresence images show a wide variety during different stages of the disease in CSCR patients. Minimal abnormalities during the early stages are followed by hyperautofluoresence in the detached area in later stages, often in a manner of inferior gravitation and at the borders of the detachments. The chronic phase is characterized by varying degrees of atrophy and areas of decreased autofluorescence surrounding areas ofchronic leaks. These changes help differentiate an active disease from an inactive state. Multifocal electroretinography(mf ERG) has the ability to demonstrate a persistent depression despite the resolution of subretinal detachments. It is therefore being investigated as a follow up tool for patients with chronic CSCR. An excellent correlation was found between changes in mf ERG and visual function. Macular microperimetry, measuring retinal sensitivity within the central visual field, is intended to compensate for the underestimation of visual impairment in patients with macular diseases. Reduced retinal sensitivity was found in areas of previous subretinal fluids in CSCR patients. The device can also serve as a follow up tool in these patients. Regarding treatment in CSCR patients, focal argon laser photocoagulation treatment may be applied to small extrafoveal leaks. However, the main purpose of this treatment is to shorten disease duration, with no advantage over observation regarding final visual outcome, rate of progression to chronic CSCR or number of recurrences. Photodynamic therapy(PDT) with verteporfin has been shown to completely resolve serous detachment in 60%-80% of patients and to have a partial affect in the remaining patients. Reduced-fluence treatment is replacing fullfluence therapy in order to minimize side effects with no accompanying reduced effectiveness. Visual acuity is also improved following reduced-fluence PDT compared to placebo. It has also been found that patients with intense hyperfluorescence are more likely to show resolution of accumulating fluid compared to patients with mild or no leakage observed on indocyanine-green angiography prior to treatment. Regarding newer treatment modalities, intravitreal injections of anti-vascular endothelial growth factor agents have a limited effect in patients with CSCR. Recent reports have not demonstrated an advantage for this treatment in regards to anatomic and functional outcome. Micropulse diode laser was not proven to be safer or more effective than argon laser or PDT. Corticosteroid antagonists, not tested in controlled trials, may have a beneficial effect in patients with CSCR. Aspirin may also play a role in treating these patients, with rapid recovery of visual acuity and reduced number of recurrences observed. In conclusion, imaging is evolving rapidly while the clinical implications of these new imaging modalities are less clear. Large randomized trials investigating different treatment modalities are still lacking.

Resolving Myopic Foveoretinal Detachment by Fovea-Saving Internal Limiting Membrane Peeling: A Case-Series Report

Background: In highly myopic eyes, myopic foveoschisis (MF), the earliest stage of myopic traction maculopathy (MTM), is present in up to 34% of patients with pathologic myopia and slowly progresses to form foveoretinal detachment (FRD) or macular hole (MH) with or without macular hole retinal detachment (MHRD) as a part of its natural history. Aim: To describe the microstructural and functional results in three highly myopic eyes that underwent macular surgery for early-stage MTM. The last postoperative structural findings were correlated with the final vision and macular automated microperimetry evaluation. Methods: We retrospectively reviewed three highly myopic eyes that underwent successful fovea-saving internal limiting membrane (FS-ILM) macular surgery for chronic FRD at Oftalmologia Integral ABC, Mexico City, Mexico. We performed postoperative multimodal microstructural and functional evaluations, including SD-OCT, SS-OCT, and microperimetric macular examinations. Results: There was a substantial difference between best-corrected visual acuity (BCVA) preoperatively and postoperatively in all three cases. Postoperative surgery was associated with significant improvement in visual acuity confirmed using a paired-sample permutation test. The mean presurgical BCVA value (LogMAR;mean ± SE) was ~0.83 ± 0.15, and the postsurgical value was ~0.43 ± 0.52 (P = 0.00065). The myopic foveoretinal detachment evaluation was ~7.3 ± 3.5 months, with a mean postoperative follow-up time of ~14 ± 4.08 months. Furthermore, postoperative multimodal imaging tests demonstrated an abnormal microstructural foveal SS-OCT pattern without evidence of macular hole (MH) development at the postoperative follow-up. Macular microperimetry confirmed a subclinical reduced macula threshold sensitivity with an anomalous retinal sensitivity analysis map and a stable central foveal fixation site. Conclusions: Even with the successful microstructural disappearance of myopic macular detachment, the last multidisciplinary functional and structural assessments demonstrated different subclinical macular alterations.

Evaluation of visual functional and morphology change in young patients with idiopathic choroidal neovascularization

Background Idiopathic choroidal neovascularization （ICNV） is an uncommon disorder affecting primarily individuals younger than the age of 50 years. In CNV patients, no apparent cause can be determined. This study aimed to evaluate the functional and morphological change of the retina with ICNV in young adults. Methods In this retrospective study, 32 eyes of 32 patients with subfoveal or juxta/extra foveal ICNV had been admitted into the Shanghai First People＇s Hospital from January 2009 to July 2010. The functional changes were evaluated using the best corrected visual acuity （BCVA） and the microperimetry in the macular area.