Spontaneous posterior vitreous detachment:A glance at the current literature

Spontaneous posterior vitreous detachment(PVD)is a common age-related condition in which prevalence tends to increase with age.Acute PVD can cause the onset of symptoms that include visual disturbances,myodesopsia and photopsia.The goal of this short review was to provide a quick glance at the important factors related to PVD based on current literature in this field,which includes incidence,symptoms,diagnosis,risk factors,and education for patients with acute symptoms,and treatments.The take home message is that an ophthalmic examination at the onset of symptoms is of utmost importance,considering that irreversible sight-threatening complications can be prevented if diagnosed and treated promptly.

Ultrasound reliability in detection of retinal tear in acute symptomatic posterior vitreous detachment with vitreous hemorrhage

Cross-sectional study of 75 consecutive patients presenting with acute symptomatic posterior vitreous detachment（ASPVD） and vitreous hemorrhage was conducted at University Eye Clinic,University Hospital ＂Sveti Duh＂,Zagreb,Croatia.To check ultrasound reliability in detecting retinal tears in patients with ASPVD,transpalpebral ultrasound of the eye and the orbit was performed followed by fundus examination initially and in 6 wk period.In 13（17%） patients membranous lesion with ultrasound characteristics of retinal tear was detected.Ophthalmoscopy confirmed the diagnosis in 8/13 patients.In 62/75 patients neither ultrasound nor clinical examination revealed retinal tear.Sensitivity of ultrasound examination was 100%,specificity 92%,positive predictive value 62% and negative predictive value 100%.Ultrasound proved to be a reliable and accurate method for detection of retinal tears in ASPVD.Given the high sensitivity and negative predictive value,negative result on B-scan ultrasound excludes the probability of the retinal tear with a high degree of certainty.

Assessment of posterior vitreous detachment on enhanced high density line optical coherence tomography

The state of the vitreo-retinal interface affects various retinal diseases, and the presence or absence of a posterior vitreous detachment （PVD） is one of the most important factors. As such, various studies studying PVD in relation to retinal disease have been performed.

Comment on “Ultrasound reliability in detection of retinal tear in acute symptomatic posterior vitreous detachment with vitreous hemorrhage”

Dear Editor,We were interested to read the paper by Kuzmanovic Elabjer et al.The purpose of the authors was to assess ultrasound reliability in detecting retinal tears in patients with acute symptomatic posterior vitreous detachment （ASPVD）. They performed transpalpebral ultrasound of the eye and the orbit followed by fundus examination initially and in 6wk period.

Posterior vitreous detachment rate following intravitreal dexamethasone injection

AIM: To determine whether intravitreal dexamethasone(DEX) implant induces posterior vitreous detachment or not. METHODS: We retrospectively reviewed 810 eyes of 405 patients who underwent intravitreal DEX implantation due to macular edema caused by diabetic and retinal venous occlusion in our clinic. The eyes having no injection were determined as the control group. The examination findings of the patients before the injection and 3 mo after the injection and optical coherence tomography(OCT) images were scanned. The pre-injection OCT findings and OCT findings of the patients having no posterior vitreous detachment(PVD) and determined to have partial PVD were compared. RESULTS: The separation in vitreoretinal adhesion and total PVD development of DEX-injected 56/208(26.9%) eyes were statistically greater in comparison with the 12/129(9.3%) eyes that had not been injected(P=0.001). PVD development was observed more in the patients that were younger, had larger macula thickness and lower visual acuity. CONCLUSION: It can be stated that intravitreal DEX implant induces PVD development. Prospective, controlled studies are required in order to determine prognosis of vitreoretinal disease in PVD-developed patients and in non-PVD-developed patients.

Application of immersion B-scan ultrasonography in diagnosis of complex retinal detachment,persistent hyperplastic primary vitreous and intraocular tumors

AIM:To evaluate the diagnostic value of panoramic immersion B-scan ultrasonography(Pano-immersion B-scan,PIB)in complex retinal detachment(RD),persistent hyperplastic primary vitreous(PHPV)and intraocular tumors.METHODS:The clinical data of 44 patients collected from May 2012 to December 2019 in Chinese PLA General Hospital was retrospectively studied.All of these patients underwent PIB of the eye,because it was difficult to diagnose by routine ocular fundus examination,conventional ultrasound or/and ultrasonic biomicroscope(UBM)due to opacity of refractive media,pupillary occlusion,large involvement or special location of the lesion.The imaging features of difficult cases in PIB were analyzed.The diagnosis accuracy rating of PIB were evaluated and contrasted with conventional ultrasound or UBM by the standard of intraoperative diagnosis or/and pathological results.RESULTS:According to intraoperative diagnosis or pathological results as gold standard,among the 44 cases,there were 19 cases missed diagnosis,misdiagnosed or difficult-to-diagnose by conventional ultrasound or UBM,including 4 cases of long-standing RD difficult to diagnose,4 cases misdiagnosed,and 11 cases incompletely observed or miss diagnosed.The diagnostic accuracy rate of PIB and conventional ultrasound or UBM were 100%(44/44)and 56.82%(25/44),and the sensitivity of them were 100%and 56.82%.All the patients underwent PIB and were diagnosed as RD(15 cases),retinal and choroidal detachment(4 cases),subchoroidal hematocele(1 case),vitreous opacity and/or organic membrane formation(4 cases),PHPV(12 cases),iris and/or ciliary body tumors(3 cases),and choroidal tumors(6 cases).According to the intraoperative diagnosis or pathological results,the diagnostic coincidence rate of PIB was 100%,which was significantly higher than conventional ultrasound and UBM.CONCLUSION:PIB can help to accurately diagnose complex RD,PHPV,and intraocular masses with special location or/and excessive size.It has important diagnostic value for patients with equivocal findings at conventional ultrasound examination.

4D label-free proteomic analysis of vitreous from patients with rhegmatogenous retinal detachment

AIM:To identify metabolites,proteins,and related pathways involved in the etiology of rhegmatogenous retinal detachment(RRD)for use as biomarkers in diagnosing and treating RRD.METHODS:Vitreous specimens were collected and liquid chromatography-tandem mass spectrometry analysis was per formed using the four-dimensional label-free technique.Statistically significant differentially expressed proteins,gene ontology(GO)terms,Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway representations,and protein interactions were analyzed.RESULTS:Nine specimens were subjected to proteomic analysis.In total,161 proteins were identified as differentially expressed proteins(DEPs),including 53 upregulated proteins and 108 downregulated proteins.GO functional analysis revealed that some DEPs were enriched in neuron-related terms and membrane protein terms.Moreover,KEGG analysis indicated that the cell adhesion molecule metabolic pathway was associated with the greatest number of DEPs.Finally,the evaluation of protein-protein interaction network revealed that DEPs were clustered in neuronal adhesion,apoptosis,inflammation and immune responses,correct protein folding,and glycolysis.CONCLUSION:Proteomic profiling is useful for the exploration of molecular mechanisms that underlie RRD.This study reveals increased expression levels of proteins related to heat shock protein content,glycolysis,and inflammatory responses in RRD.Knowledge regarding biomarkers of RRD pathogenesis may help to prevent the occurrence of RRD in the future.

Expression levels of ROS and Atg proteins in the vitreous in rhegmatogenous retinal detachment

AIM:To detect the concentrations of reactive oxygen species(ROS),transient receptor potential mucin-1(TRPML1),and autophagy-related(Atg)proteins(LC3-Ⅰ,LC3-Ⅱ,and Beclin1)in vitreous humor of patients with simple rhegmatogenous retinal detachment(RRD).METHODS:RRD patients enrolled as the RRD group,and patients with idiopathic macular hole(IMH)and idiopathic macular epiretinal membrane(IMEM)were enrolled as control group.The levels of ROS,TRPML1,LC3-Ⅰ,LC3-Ⅱ,and Beclin1 in vitreous humor of patients in the RRD and control groups were detected by enzyme-linked immunosorbent assay(ELISA).RESULTS:The RRD group included 28 eyes 28 patients and had a higher concentration of ROS in vitreous humor(631.86±18.05 vs 436.34±108.22 IU/m L,P<0.05).The ROS level in patients with a wide retinal detachment(RD)extent(RD range≥1/2)was higher than that with a narrow RD extent(RD range<1/2,P<0.05).ROS concentration was negatively correlated with RD time(r=-0.46,P=0.01).The expression levels of LC3-Ⅰand Beclin1 significantly decreased in RRD(P<0.05),but there were no correlations with the RD time,RD extent,or macular involvement.CONCLUSION:In eyes with RRD,the concentration of ROS in vitreous humor increases and the expression levels of Atg proteins decrease,reflecting possibly that autophagy is inhibited.

Visual Outcomes and Risk of Rhegmatogenous Retinal Detachment Following Posterior Capsule Rupture during Cataract Surgery: With vs without Dropped Nuclear Lens Fragments

Background: Cataract surgery is the most frequently performed surgery worldwide. Posterior capsule rupture (PCR) remains one of the most common complications of cataract surgery and a major risk factor for poor visual outcomes. Cataract surgeries complicated by PCR and vitreous loss are managed with anterior vitrectomy at the time of surgery. However, the situation can be further complicated by dropping lens particles into the vitreous cavity necessitating a secondary pars plana vitrectomy (PPV). Purpose: To compare the visual outcomes and risk of rhegmatogenous retinal detachment (RRD) between eyes that required anterior vitrectomy (AV) alone for the management of vitreous loss and eyes that required AV and subsequent PPV for the management of dropped nuclear lens fragments (DNLF) following cataract surgery complicated by PCR in a tertiary care teaching hospital in Saudi Arabia. Methods: Medical records of patients in whom PCR occurred during phacoemulsification cataract surgery requiring AV or subsequent PPV for DNLF were retrospectively reviewed over a 6-year period from January 2016 to December 2021. Results: PCR occurred in 183 (2.3%) of 7757 consecutive eyes that underwent phacoemulsification cataract surgery during the study period. Seven eyes were excluded from analysis for missing data or short follow-up. Of the 176 eyes, 147 eyes (83.5%) were managed with AV alone, and the remaining 29 eyes (16.5%) underwent a secondary PPV for DNLF. After excluding eyes with pre-existing ocular pathology, final best-corrected visual acuity (BCVA) was similar in both groups with a mean of 0.32 logMAR (P = 0.99). Two of 147 eyes (1.4%) in the AV group developed RRD with poor final BCVA whereas none of the eyes in DNLF group developed RRD. Conclusion: The risk of RRD is lower in eyes that required PPV for DNLF than in eyes that were managed with AV alone following PCR during cataract surgery. The poor visual outcomes in eyes that suffered RRD underscore the importance of postoperative retinal examination and early detection of retinal breaks.

Posterior vitreous cortex contributes to macular hole in highly myopic eyes with retinal detachment

Background It was well known that tangential vitreoretinal traction and epiretinal membrane play important roles during the formation of macular hole （MH） associated with retinal detachment （RD） in highly myopic eyes. But it was not clear about the correlations between anteroposterior traction, posterior vitreous cortex （PVC） and MH-RD. The vitreous status in highly myopic eyes were analyzed to explore the effect of PVC in the role of MH-RD formation. Methods Sixteen consecutive highly myopic eyes with RD due to MH were retrospectively analyzed from January 2009 to April 2009. The preoperative examinations for detecting posterior vitreous detachment （PVD） and vitreoretinal traction included B-mode ultrasonography and optical coherence tomography （OCT）. The residual PVC and PVD were confirmed intraoperatively during triamcinolone acetonide （TA） assisted vitrectomy. Results Under ultrasonography, the preoperative PVD patterns were stratified as： complete PVD in three （19%） eyes, partial PVD in eight （50%） eyes, and no PVD in five （31%） eyes. OCT confirmed vitreoretinal traction and no complete PVD in 10 （63%） eyes, including anteroposterior traction in four eyes and tangential traction in six eyes. During TA-assisted vitrectomy, it was confirmed that no complete PVD existed in 16 eyes, including six eyes （38%） finally diagnosed of partial PVD, and five （31%） eyes with vitreoschisis. Anteroposterior vitreoretinal traction around MH is always in conjunction with partial PVD （67%）, and high proportion （80%） of vitreoschisis is associated with tangential vitreoretinal traction. Comparing with the precision of TA staining of PVD diagnosis, the coincidence rate of ultrasonography was 69% （P=0.02）, and that of OCT was 63% （P 〈0.01）. Conclusions The residual PVC due to partial PVD or vitreoschisis may cause the anteroposterior or tangential traction of macular area, which contributes to the formation of MH and subsequent RD in highly myopic eyes. And it is necessary to realize the vitreoretinal relationship and assess the status of PVC synthetically for surgery by combined ultrasonography and OCT preoperatively and TA staining intraoperatively.

Clinical observation of vitrectomy combined with endolaser photocoagulation at the edge of posterior scleral staphyloma for macular hole retinal detachment in high myopia

AIM: To observe the clinical effect of pars plana vitrectomy(PPV) and silicone oil filling surgery combined with intraoperative posterior scleral staphyloma(PS) marginal retinal photocoagulation in the treatment of high myopic macular hole retinal detachment(MHRD) with PS.METHODS: This was a retrospective clinical study. From May 2017 to March 2020, 62 MHRD patients with PS(62 eyes) were enrolled in the study. Patients were divided into 23 G PPV combined with PS marginal retina intraoperative photocoagulation group(combined group) and conventional surgery group(conventional group), with 31 eyes in each. Triamcinolone acetonide and indocyanine green were used to remove the epiretinal membrane and the posterior macular inner limiting membrane(ILM). In the combined group, 2 to 3 rows of retinal photocoagulation were performed on the edge of the PS. The patients were followed up for an average of 8.34±3.21 mo. The first retinal reattachment rate, macular hole closure rate, Duration of silicone oil tamponade, best corrected visual acuity(BCVA) and average number of operations were observed and compared between the two groups.RESULTS: The first retinal reattachment rates of the eyes in the combined group and the conventional group were 96.7%(29/31) and 67.7%(21/31), respectively(χ~2=6.613, P=0.010). The macular hole closure rates in the combined group and the conventional group were 74.2%(23/31) and 67.7%(21/31), respectively(χ~2=0.128, P=0.721). The Duration of silicone oil tamponade of the patients in the combined group was lower than that of the routine group(t=-41.962, P≤0.001). Postoperative log MAR BCVA values of patients in the combined group and the conventional group were 1.27±0.12 and 1.26±0.11, compared with the log MAR BCVA before surgery, each group was improved(t=19.947, t=-19.517, P≤0.001, P≤0.001). There was no significant difference in the log MAR BCVA between the eyes of the two groups(t=-0.394, P=0.695). The average numbers of operations on the eyes in the conventional group and the combined group were 2.39±0.62 and 2.06±0.25 times, the combined group had fewer operations on average(t=-2.705, P=0.009). CONCLUSION: Intraoperative PPV treatment of MHRD with PS combined with PS marginal endolaser photocoagulation can effectively increase the rate of retinal reattachment after the first operation, reduce the number of repeated operations, and reduce the postoperative duration of silicone oil tamponade.

The clinical features of posterior scleritis with serous retinal detachment: a retrospective clinical analysis

AIM: To summarize the clinical features, systemic associations, risk factors and choroidal thickness (CT) changing in posterior scleritis (PS) with serous retinal detachment.METHODS: This retrospective study included 23 patients diagnosed PS with retinal detachment from August 2012 to July 2017. All patients' medical history and clinical features were recorded. The examinations included best corrected visual acuity (BCVA), intraocular pressure (IOP), fundus examination, and routine eye examinations. Posterior coats thickness (PCT) was determined by B-scan ultrasound, the CT was measured by enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT) and clinical data were compiled and analyzed.RESULTS: After application of extensive exclusion criteria, 23 patients with PS remained (13 females, 10 males). The average age at presentation was 29.5±9.24 years old. Ocular pain and blurred vision were the two most common complained symptoms by patients. Anterior scleritis occurred in 12 patients, which was confirmed by ultrasound biomicroscopy (UBM) examination. Despite all patients displaying serous retinal detachment in their macula, no fluorescein leakage was observed in the macular area. Optic disc swelling was documented in 10 of the 23 eyes. From B-scan ultrasound examination, the PCT in creased with fluid in Tenon's capsule demonstrated as a typical T-sign. The average PCT was 2.51±0.81 mm in the PS-affected eyes and only 1.09±0.29 mm in the unaffected eye (P<0.0001). The subfoveal CT was 442.61 ±55.61 μm, which correlated with axis length (r=-0.65, P=0.001) and PCT (r=0.783, P<0.001). The BCVA and IOP did not correlate with either CT or PCT.CONCLUSION: PS with serous retinal detachment presented a variety of symptoms, such as pain, visual loss, and physical indicators. Typical T-sign detected by B-scan ultrasound is a useful confirmatory sign for PS diagnosis. Pathological increases in CT might be a potential predictive factor for inflammation.

A simple new technique for the induction of residual posterior vitreous cortex removal and membrane peeling

AIM:To describe a quick,cost-effective alternative to using a scraper to remove the residual posterior vitreous cortex and create an inner limiting membrane(ILM)flap during vitrectomy.METHODS:The surgical technique and a retrospective interventional single-center series of cases were described.A hook was made on the tip of a conventional syringe needle(outer diameter,0.6 mm;23 gauge)by bending the needle against a plate.We used this hook to remove the residual posterior vitreous cortex and create an ILM flap during vitrectomy.The efficacy and safety of using this instrument in ophthalmological procedures for a variety of vitreoretinal disorders were evaluated.RESULTS:The hook was effective for removing focal or diffuse residual posterior vitreous cortex in eyes with rhegmatogenous retinal detachment,proliferative diabetic retinopathy,and pathological myopia.It was also successfully used to make a free edge of the ILM and help strip the epiretinal membrane.There were no serious complications associated with using the hook in delicate ophthalmological procedures.CONCLUSION:The hook,made by bending a conventional needle,is a simple and cost-effective instrument for removing residual posterior vitreous vortex and to create epiretinal and ILM flaps during vitrectomy in eyes with various vitreoretinal diseases.

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.

Missed retinal breaks in rhegmatogenous retinal detachment

AIM： To evaluate the causes and associations of missed retinal breaks（MRBs） and posterior vitreous detachment（PVD） in patients with rhegmatogenous retinal detachment（RRD）.METHODS： Case sheets of patients undergoing vitreo retinal surgery for RRD at a tertiary eye care centre were evaluated retrospectively. Out of the 378 records screened, 253 were included for analysis of MRBs and191 patients were included for analysis of PVD,depending on the inclusion criteria. Features of RRD and retinal breaks noted on examination were compared to the status of MRBs and PVD detected during surgery for possible associations.RESULTS： Overall, 27% patients had MRBs. Retinal holes were commonly missed in patients with lattice degeneration while missed retinal tears were associated with presence of complete PVD. Patients operated for cataract surgery were significantly associated with MRBs（P =0.033） with the odds of missing a retinal break being1.91 as compared to patients with natural lens. Advanced proliferative vitreo retinopathy（PVR） and retinal bullae were the most common reasons for missing a retinal break during examination. PVD was present in 52% of the cases and was wrongly assessed in 16%. Retinal bullae,pseudophakia/aphakia, myopia, and horse shoe retinal tears were strongly associated with presence of PVD.Traumatic RRDs were rarely associated with PVD. CONCLUSION： Pseudophakic patients, and patients with retinal bullae or advanced PVR should be carefully screened for MRBs. Though Weiss ring is a good indicator of PVD, it may still be over diagnosed in some cases. PVD is associated with retinal bullae and pseudophakia, and inversely with traumatic RRD.

Is there a relationship between dopamine and rhegmatogenous retinal detachment?

Dopamine and its receptors have been widely studied in the neurological conditions and in the retina. In this study, we evaluated the possible role of dopamine in rhegmatogenous retinal detachment(RRD) by comparing the amount of 3,4-dihydroxyphenylacetic acid(DOPAC), a surrogate index of retinal dopamin levels, in the vitreous sample of patients affected by RRD with those affected by macular pucker and vitre ous hemorrhage. Our results showed that significantly higher levels of DOPAC were found in the vitreou sample of patients affected by RRD compared with those affected by vitreous hemorrhage and macula pucker(P = 0.002). Specifically, no trace of the substance was found in vitreous hemorrhage and macula pucker samples. A slightly significant positive correlation was found among DOPAC and post-operativ best corrected visual acuity(r = 0.470, P = 0.049). No correlation was found between DOPAC and the day elapsed between diagnosis and surgery(P = 0.317). For the first time our findings suggest that DOPAC i released in RRD, but not in other retinal diseases such as vitreous hemorrhage and macular pucker. More over, we showed a correlation between visual acuity outcome and the amount of DOPAC in the vitreous This might have a potential, although still unknown, implication in the pathogenesis of the disease and/o in the associated photoreceptors loss. This study was approved by the Ethics Committee of Rome Tor Ver gata University Hospital(R.S.92.10) on September 24, 2010.

Reliability of the ocular trauma score for the predictability of traumatic and post-traumatic retinal detachment after open globe injury

AIM: To elucidate the question of whether the ocular trauma score(OTS) and the zones of injury could be used as a predictive model of traumatic and post traumatic retinal detachment(RD) in patients with open globe injury(OGI).METHODS: A retrospective observational chart analysis of OGI patients was performed. The collected variables consisted of age, date, gender, time of injury, time until repair, mechanism of injury, zone of injury, injury associated vitreous hemorrhage, trauma associated RD, post traumatic RD, aphakia at injury, periocular trauma and OTS in cases of OGI. RESULTS: Totally 102 patients with traumatic OGI with a minimum of 12 mo follow-up and a median age at of 48.6 y(range: 3-104 y) were identified. Final best corrected visual acuity(BCVA) was independent from the time of repair, yet a statistically significant difference was present between the final BCVA and the zone of injury. Severe trauma presenting with an OTS score Ⅰ(P<0.0001) or Ⅱ(P<0.0001) revealed a significantly worse BCVA at last follow up when compared to the cohort with an OTS score >Ⅲ. OGI associated RD was observed in 36/102 patients(35.3%), whereas post traumatic RD(defined as RD following 14 d after OGI) occurred in 37 patients(36.3%). OGI associated RD did not correlate with the OTS and the zone of injury(P=0.193), yet post traumatic RD correlated significantly with zone Ⅲ injuries(P=0.013). CONCLUSION: The study shows a significant association between lower OTS score and zone Ⅲ injury with lower final BCVA and a higher number of surgeries, but only zone Ⅲ could be significantly associated with a higher rate of RD.

Effect of the position of the corneal lamella on the frequency of its detachment

AIM:To determine the influence of gaps[places where neither the donor's nor the recipient's Descemet's membrane(DM)is present]and overlaps(places where the recipient's DM is covered by the donor's DM)on the frequency of postoperative detachment of DM endothelial keratoplasty(DMEK)lamellae.METHODS:Totally 64 eyes of 64 patients with Fuchs'endothelial dystrophy or bullous keratopathy indicated for DMEK were randomly divided in two groups.The diameter of the implanted DMEK lamella was the same in both groups(8 mm),but we changed the diameter of the removed recipient DM.In the first group(32 eyes),the circular area was approximately 8.5 mm(gaps);in the second group(32 eyes),the diameter was 7.5 mm(overlaps).Postoperatively we noted all cases of detachment visible on the slit lamp and these cases we indicated for rebubbling.We also measured the uncorrected distance visual acuity(UDVA)as well as corrected distance visual acuity(CDVA)in decimal and postoperative endothelial cell density(ECD).The minimum follow-up time was 6mo.RESULTS:The number of rebubbling procedures in the entire group of patients was 13,i.e.,20.3%,with 6 eyes(18.7%)in the gap group,and 7 eyes(21.9%)in the overlap group.Lamella replacement(re-DMEK)was required in 3(gap group)and 2 patients(overlap group),respectively.The dif ference between the groups was statistically insignificant.The UDVA was 0.54±0.21 in the gap group and 0.58±0.24 in the overlap group.The CDVA was 0.74±0.22 and 0.80±0.16,respectively.ECD was 1920±491 and 2149±570 cells/mm2.The small differences between both groups were not statistically significant.CONCLUSION:We do not notice any difference in the group of patients with overlaps or gaps of DM.The presence of small areas of gaps or overlaps does not affect the frequency of detachment of the DMEK lamellae.

Comparison of two Nd:YAG laser posterior capsulotomy: cruciate pattern vs circular pattern with vitreous strand cutting

AIM： To investigate the effects and safety of neodymium： yttrium-aluminium-garnet（Nd：YAG） laser posterior capsulotomy with vitreous strand cuttingMETHODS： A total of 40 eyes of 37 patients with symptomatic posterior capsular opacity（PCO） were included in this prospective randomized study and were randomly subjected to either cruciate pattern or round pattern Nd：YAG posterior capsulotomy with vitreous strand cutting（modified round pattern）. The best corrected visual acuity（BCVA）, intraocular pressure（IOP）, refractive error, endothelial cell count（ECC）, anterior segment parameters, including anterior chamber depth（ACD） and anterior chamber angle（ACA） were measured before and 1 mo after the laser posterior capsulotomy. RESULTS： In both groups, the BCVA improved significantly（P〈0.001 for the modified round pattern group, P=0.001 for the cruciate pattern group）; the IOP and ECC did not significantly change. The ACD significantly decreased（P〈0.001 for both） and the ACA significantly increased（P=0.001 for the modified round pattern group and P=0.034 for the cruciate group）. The extent of changes in these parameters was not significantly different between the groups.CONCLUSION： Modified round pattern Nd：YAG laser posterior capsulotomy is an effective and safe method for the treatment of PCO. This method significantly changes the ACD and ACA, but the change in refraction is not significant. Modified round pattern Nd：YAG laser posterior capsulotomy can be considered a good alternative procedure in patients with symptomatic PCO.

Safety and efficacy of posterior sub-Tenon＇s carboplatin injection versus intravitreal melphalan therapy in the management of retinoblastoma with secondary vitreous seeds

AIM： To evaluate the safety and efficacy of posterior sub-Tenon＇s carboplatin injection compared to intravitreal melphalan injection in the management of retinoblastoma （RB） with secondary vitreous seeds. The outcome measures were vitreous seeds regression, need for other treatment modalities to achieve ocular salvage and treatment side effects. METHODS： A prospective interventional comparative nonrandomized study included RB eyes developed secondary vitreous seeds during the period of follow up. They subdivided into two groups： study group Ⅰ where posterior sub-Tenon＇s carboplatin （20 mg/2 mL） was injected and study group Ⅱ where intravitreal melphalan （20 μg/0.1 mL） was injected. The injections repeated every 2-4wk. RESULTS： Thirty-three eyes were included in the study. Seventeen eyes （16 patients） in study group Ⅰ and 16 eyes （16 patients） in study group Ⅱ. Ten eyes （30.3%） were completely salvaged following local chemotherapies, Ocular salvage was 23.5% following posterior sub-Tenon＇s carboplatin injection versus 37.5% following intravitreal melphalan raised to 47.1% and 75% with addition of external beam radiotherapy （EBR） with no statistically significant difference between the study groups （P=0.16）. A statistically significant correlation was found between ocular salvage rate and type of vitreous seeds either dust, spheres and clouds （r=0.42, P=-0.015） and eyes harbor new solid tumor growth （r=0.35, P=0.045）. The mean and median follow up periods following local chemotherapy injections were 2.0y in the study group Ⅰand 2.37y in the study group Ⅱ. Few complications were reported： periorbital edema in all eyes and ocular motility disturbances in 13 eyes （76.5%） following posterior sub-Tenon＇s carboplatin injection. Vitreous hemorrhage developed in 2 eyes （12.5%） and localized retinopathy in 5 eyes （31.25%） following intravitreal melphalan. ~ CONCLUSION： Local chemotherapy for treatment of RB with secondary vitreous seeds is safe and can salvage 30.3% of eyes without EBR. There is a superiority of intravitreal melphalan in ocular salvage however, no statistically significant difference between both groups.