Silicone oil insulation effects on flash electroretinogram and visual evoked potential in patients with retinal detachment / Efectos del aislamiento del aceite de silicona sobre el electrorretinograma flash y el potencial evocado visual en pacientes con desprendimiento de retina

Background: Silicone oil is used as endotamponade following vitreoretinal surgery to maintain the retina reattached when indicated. This study investigates the hypothesis that silicone oil causes insulation effects on the retina by affecting its response to light. Methods: Electrophysiological responses to a flash stimulus were recorded using full-field electroretinography (ERG) and visual evoked potentials (VEP). Recordings were performed in 9 patients who underwent surgery for retinal detachment, before (1–2 days) and after (2–3 weeks) silicone oil removal (SOR) in both the study and the control eye. Flash ERG and VEP recordings were performed according to the ISCEV standard protocol. Results: Statistically significant differences were found in the study eye in the amplitudes of the ERG responses and their corresponding ratios, i.e. the amplitude after SOR over the amplitude before SOR, in all conditions tested. No differences were observed in the control eye. The mean ratio of photopic ERG response was 3.4 ± 2.4 for the study and 1.0 ± 0.3 for the control eye (p<0.001). The mean ratio of ERG flicker response was 3.1 ± 2.4 and 1.0 ± 0.3, respectively (p = 0.003). Scotopic flash ERG ratio was 5.0 ± 4.4 for the study and 1.3 ± 0.6 for the control eye (p = 0.012). No differences were observed for the amplitude and latency of flash VEP response after SOR. Conclusions: Silicone oil causes a reduction in flash ERG responses; no effect was found on flash VEP responses. ERGs in eyes filled with silicone oil should not be considered representative of retinal functionality, in contrast to VEPs, which are not affected by silicone oil presence.(AU)

Macular edema after surgery to treat rhegmatogenous retinal detachment: 1-year follow-up, incidence, and associated risk factors.

PURPOSE: To clarify the postoperative incidence of macular edema in patients undergoing surgery to repair rhegmatogenous retinal detachment and identify the associated risk factors. METHODS: In this prospective, observational study, 79 patients who underwent surgery to correct rhegmatogenous retinal detachment using pars plana vitrectomy with silicone oil injection were analyzed. Patients were followed up postoperatively at 7, 30, 90, 180, and 365 days. At each visit, optical coherence tomography was performed to assess the presence or absence of macular edema. were analyzed as possible risk factors for macular edema: age, sex, macular status (attached or detached), presence of vitreoretinal proliferation, history of previous intraocular surgery, reported time of symptoms suggestive of rhegmatogenous retinal detachment up to the date of surgery, and the surgical modality performed. RESULTS: The 1-year macular edema prevalence rate was 26.6%. In the adjusted analysis, older patients had a higher risk of macular edema, and each 1-year increase in age increased the risk of macular edema by 6% (95% confidence interval = 1.00-1.12). The macular status, vitreoretinal proliferation, the surgical technique used, prior intraocular surgery, and the intraocular lens status were not identified as risk factors. However, the incidence of macular edema increased up to 180 days after surgery, peaking at 10.6%, and then decreased until 365 days after surgery. CONCLUSION: Macular edema was a common complication after surgery to treat rhegmatogenous retinal detachment, with its incidence peaking between 30 and 180 days after surgery. Age was an important risk factor for macular edema in this cohort.

Surgical management of a case of giant retinal tear with closed funnel retinal detachment in a pediatric patient.

BACKGROUND: A 7-year-old male child was brought by his parents with a complaint of low vision in both eyes for 2 months. The child had low vision in both the eyes for 1.5 years, but the parents noticed when it worsened further 2 months back, leading to profound vision loss. On ophthalmic evaluation, the child did not perceive light in the right eye. Furthermore, anterior segment examination showed complicated cataract and open funnel retinal detachment with intra-retinal cysts in ultrasound (USG) B scan. In the left eye, he could appreciate light but with poor fixation. Fundus evaluation of the left eye showed total retinal detachment on indirect ophthalmoscopy, which was confirmed on USG B scan. Since the right eye had poor visual potential, no intervention was done. The left eye underwent pars plana vitrectomy with silicone oil tamponade, which led to successful anatomical outcomes. The immediate and late postoperative periods were uneventful, and the child was kept under follow-up and was observed closely. PURPOSE: To educate regarding the surgical management of giant retinal tears in a pediatric patient. SYNOPSIS: To inform regarding the surgical challenges faced and steps adopted to manage such cases. HIGHLIGHTS: Through this case, we want to highlight the challenges faced, such as delayed presentation, difficult preoperative evaluation, intraoperative difficulties such as mobile retina, absence of posterior vitreous detachment, and tenacious vitreous gel. We also want to emphasize on the steps taken to overcome the challenges. CONCLUSION: In such challenging situations, effective planning, careful manipulation, and persistence are essential for success. VIDEO LINK: https://youtu.be/T0Gy6Wj13zI.

Silicone Oil Tamponade for Therapy of Primary Retinal Detachment in Patients Who Live at High Altitudes.

BACKGROUND: Uncomplicated rhegmatogenous retinal detachment (RRD) is mainly treated with vitrectomy and gas tamponade or, alternatively, scleral buckling surgery. However, gas tamponade inflates at high altitudes, causing significant complications. Silicone oil (SO) tamponade volume is unaffected by atmospheric pressure and may be used in patients who live or must undertake travel at high altitudes. PURPOSE: To determine the anatomical and functional outcomes after pars plana vitrectomy (PPV) with SO tamponade in primary uncomplicated RRD. METHODS: Twenty-eight consecutive cases of patients operated between January 2017 and December 2022 in Jules-Gonin University Eye Hospital in Lausanne were included in this retrospective study. All patients had a follow-up of at least 3 months after SO removal. RESULTS: Primary reattachment was achieved in all 28 eyes. Mean follow-up was 17.2 months (range: 3 - 51 months) after SO removal. Mean age at the time of intervention was 60 years (range: 21 - 80 years). Vision was stabilized or improved in 27 eyes (96%). One patient demonstrated a slight visual acuity decrease due to cataract formation at the last follow-up. In all patients, SO was removed 2 to 5 months after primary repair. In 14 of the 21 phakic patients, concomitant cataract surgery was performed. No surgical complications were encountered. Postoperatively, 5 (18%) patients had ocular hypertension, presumably steroid related, that was successfully controlled with topical treatment. CONCLUSION: PPV with SO injection seems to be a safe and efficient surgical approach in the treatment of primary uncomplicated RRD in patients living at high altitudes and was associated with good anatomical and functional outcome in our series. However, the need for a follow-up surgery to remove SO should be weighed in these cases.

Management of macula-on giant retinal tear detachments- outcome of pars-plana-vitrectomy with silicone oil versus gas tamponade.

BACKGROUND: To compare the outcome of eyes with a macula-on giant retinal tear (GRT) detachment treated with pars-plana-vitrectomy (PPV) depending on the used endotamponade. METHODS: All consecutive cases with a macula-on GRT-associated rhegmatogenous retinal detachment (RRD) managed with PPV between 2007 and 2022 were retrospectively assessed depending on the selected endotamponade. By reviewing medical charts and surgical protocols the pre- and intraoperative parameters were analysed in detail. The number of vitreoretinal (VR) procedures needed for reattachment, the redetachment rate and the functional outcome were evaluated. Eyes treated with primary silicone oil (SO) tamponade were compared to eyes with primary gas tamponade. Cases with pre-existing conditions affecting outcome e.g. macula-off situation, history of trauma, status after complicated cataract surgery, former VR surgery or proliferative vitreoretinopathy grade C or higher were excluded. RESULTS: Overall, 51 eyes of 45 patients with a macula-on GRT detachment were treated with PPV and SO (n = 32; 63%) or gas (n = 19; 37%) endotamponade in the observed period. Eyes with primary SO tamponade underwent on average 2.3 (SD 0.8) VR procedures and had a redetachment rate of 13% (n = 4). Eyes with gas tamponade showed a higher redetachment rate of 32% (n = 6) with a mean number of 1.6 (SD 1.0) PPV procedures. Postoperative best-corrected visual acuity (BCVA) was significantly better in eyes with primary gas tamponade (mean logMAR BCVA 0.32; SD 0.30) compared to eyes with SO (mean logMAR BCVA 0.60; SD 0.42; p = 0.008). CONCLUSIONS: Surgical management of GRT-associated RRDs is complex. In clinical routine often SO is used as endotamponade. Because of known disadvantages (second procedure necessary for SO removal, unexplained SO-related visual loss, secondary glaucoma, SO emulsification) some VR surgeons prefer a gas tamponade. In our cohort, eyes with a gas compared to SO tamponade showed higher redetachment rates. However, the final postoperative BCVA was significantly better in eyes with gas compared to SO tamponade. TRIAL REGISTRATION: The trial protocol was approved by the local ethics committee on 25th of November 2022 (Ethikkommission der Universität Regensburg, Votum 22-3166-104).

Progressive retinoschisis and retinal detachment after uncomplicated macular hole repair surgery.

PURPOSE: To report a rare case of progressive retinoschisis and retinal detachment after uncomplicated macular hole (MH) surgery. CASE DESCRIPTION: A 67-year-old man with recent onset vision complaints in the right eye (visual acuity - 20/30), was diagnosed with a small idiopathic full-thickness MH. He underwent a 3-port 25G pars plana vitrectomy surgery with internal limiting membrane peeling and air endotamponade. RESULTS: MH closed with a normal foveal contour and intact retinal layers by the 1st post operative week and vision improved to 20/20. At the 7th week follow-up period, the patient complained of visual disturbances in his right eye for 2 days. Optical coherence tomography scans revealed development of peripheral retinoschisis which progressed towards the macula over the next 4 weeks. At the 13th week following the retinal surgery, patient developed sudden profound vision loss to hand motions and a total retinal detachment was noted. He underwent a second retinal surgery with retinectomy to the stiff retina and silicone oil endotamponade. At the last follow-up visit 8 weeks after the second surgery, the visual acuity had improved to 20/120 and the retina was well-attached with silicone oil in place. CONCLUSION: We present a rare case of progressive retinoschisis and retinal detachment caused by residual ILM contraction after MH repair surgery. To the best of our knowledge, no such complication after MH repair surgery has been reported in the literature.

One-Year Outcomes of the PAUL Glaucoma Implant Compared With the Ahmed Glaucoma Valve for the Treatment of Silicone Oil Glaucoma.

PRCIS: Longer-term studies with a larger sample size are needed to demonstrate the superiority or equivalence of these procedures. OBJECTIVE: To evaluate the outcomes of the PAUL glaucoma implant (PGI) and Ahmed glaucoma valve (AGV) in patients with secondary glaucoma caused due to silicone oil emulsification. PATIENTS AND METHODS: A retrospective examination was conducted using the medical records of 36 patients who developed secondary glaucoma due to silicone oil emulsification after vitreoretinal surgery and then underwent PGI and AGV implantation surgery. The main outcome measures in the PGI and AGV groups were intraocular pressure (IOP) and its change, the number of antiglaucoma medications, and postoperative complications during the 12-month follow-up period. IOP of <6 mm Hg is used to define hypotonia. RESULTS: There was no statistically significant difference among the patients who underwent PGI and AGV surgeries in terms of IOP averages, both preoperatively and postoperatively on day 1, week 1, month 1, month 3, month 6, and month 12 ( P > 0.05). Before PGI and AGV implantation, the mean IOP was 40 ± 13 mm Hg and 39.3 ± 10 mm Hg, and the mean number of medications was 3.8 ± 0.4 and 4 ± 0, respectively. At the end of the 12-month follow-up period, the mean IOP was 13.5 ± 2.2 ( P < 0.001) mm Hg and 14.9 ± 4.2 ( P < 0.001) mm Hg, whereas the mean number of glaucoma medications decreased to 1.7 ± 1.3 ( P < 0.001) and 1.9 ± 1.8 ( P < 0.001) in the PGI and AGV groups, respectively. Surgical success was achieved in 17 of 18 eyes (94%) in the PGI group and 16 of 18 eyes (89%) in the AGV group. CONCLUSIONS: Although the outcomes were similar in both the PGI and AGV groups, complications requiring medical and surgical intervention were less common in the PGI group. Longer-term studies with a larger sample size are needed to demonstrate the superiority or equivalence of these procedures.

Improved Outcomes with Heavy Silicone Oil in Complex Primary Retinal Detachment: A Large Multicenter Matched Cohort Study.

PURPOSE: To establish whether Densiron 68, a heavier-than-water endotamponade agent, is an effective alternative to conventional light silicone oil in primary rhegmatogenous retinal detachment (RD) surgery for eyes with inferior breaks in the detached retina and severe proliferative vitreoretinopathy (PVR). DESIGN: Cohort study of routinely collected data from the European Society of Retina Specialists and British and Eire Association of Vitreoretinal Surgeons vitreoretinal database between 2015 and 2022. PARTICIPANTS: All consecutive eyes that underwent primary rhegmatogenous RD surgery using Densiron 68 or light silicone oil as an internal tamponade agent. METHODS: To minimize confounding bias, we undertook 2:1 nearest-neighbor matching on inferior breaks, large inferior rhegmatogenous RDs, PVR, and, for visual analyses, baseline visual acuity (VA) between treatment groups. We fit regression models including prognostically relevant covariates, treatment-covariate interactions, and matching weights. We used g-computation with cluster-robust methods to estimate marginal effects. For nonlinear models, we calculated confidence intervals (CIs) using bias-corrected cluster bootstrapping with 9999 replications. MAIN OUTCOME MEASURES: Presence of a fully attached retina and VA at least 2 months after oil removal. RESULTS: Of 1061 eyes enrolled, 426 and 239 were included in our matched samples for anatomic and visual outcome analyses, respectively. The primary success rate was higher in the Densiron 68 group (113 of 142; 80%) compared with the light silicone oil group (180 of 284; 63%), with an adjusted odds ratio of 1.90 (95% CI, 1.63-2.23, P < 0.001). We also observed a significant improvement favoring Densiron 68 of -0.26 logarithm of the minimum angle of resolution (logMAR) in postoperative VA between the 2 groups (95% CI, -0.43 to -0.10, P = 0.002). The anatomic benefit of using Densiron 68 in eyes with inferior retinal breaks and large detachments was more pronounced among eyes with PVR grade C. We found no evidence of visual effect moderation by anatomic outcome or foveal attachment. CONCLUSIONS: Densiron achieved higher anatomic success rates and improved visual outcomes compared with conventional light silicone oil in eyes with inferior retinal pathology and severe PVR. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Development of cystoid macular edema after uneventful cataract surgery in eyes with a history of vitrectomy using silicone oil versus gas tamponade.

BACKGROUND/OBJECTIVES: The purpose of this study is to investigate whether history of silicone oil tamponade may predispose to the development of cystoid macular edema (CMO) following uneventful post-vitrectomy cataract surgery. SUBJECTS/METHODS: This is a retrospective study that was conducted at a single academic institution. Records of patients who underwent pars plana vitrectomy (PPV) with or without silicone oil tamponade and subsequent cataract surgery between 2017-2020 were reviewed. Macular optical coherence tomography (OCT) findings up to 4 years after surgery were assessed. RESULTS: A total of 95 eyes were included. Forty-one eyes underwent cataract surgery and had a history of PPV with silicone oil tamponade (Group 1). Fifty-four eyes underwent cataract surgery by phacoemulsification and had a history of PPV with gas tamponade (Group 2). Average follow up time after cataract surgery was 41.1 months. In Group 1, the incidence of OCT-detected CMO was 39.0%, compared to 27.8% in Group 2 (p = 0.247). The incidence of clinically significant CMO in Group 1 was 22.0%, compared to 18.5% in Group 2 (p = 0.679). The duration of CMO was significantly longer in Group 1 (p = 0.041) and cases were less likely to resolve by the last follow up visit (p = 0.040). CONCLUSIONS: The incidence of OCT-detected or clinically significant pseudophakic CMO is not significantly different between eyes with prior PPV with gas tamponade versus silicone oil tamponade. However, CMO after uneventful cataract surgery may have a prolonged course if there is history of silicone oil tamponade, requiring longer treatment.

Corneal Toxicity of Intravitreal Methotrexate Used for the Treatment of Proliferative Vitreoretinopathy in Silicone Oil-Filled Eyes: A Case Series.

PURPOSE: The purpose of this study was to evaluate the corneal toxicity of intravitreal methotrexate used for the prevention of proliferative vitreoretinopathy (PVR). METHODS: In this retrospective case series, eyes with recurrent retinal detachment secondary to PVR were treated with intravitreal injections of 400 µg methotrexate at an average frequency of every 7 days after vitrectomy with silicone oil tamponade. Corneas were examined for corneal epitheliopathy by slit-lamp biomicroscopy before each injection. RESULTS: Thirteen eyes of 12 patients were reviewed. All had a history of recurrent retinal detachment secondary to PVR treated with vitrectomy and silicone oil. The median age was 35 years (range: 9-83). Four patients (33%) were female. The median follow-up duration was 8 weeks (range: 5-10). The median BCVA (logMAR notation) was 2.00 preoperatively, 2.00 at 1 month postoperatively, and 2.00 at the most recent follow-up (P = 0.969). Ten eyes (77%) were pseudophakic. Nine eyes (69%) had a preexisting ocular comorbidity. The median number of injections was 8 (range: 5-10). The median interval time between each injection was 7.0 days (range: 5.8-10.5), and the median follow-up period beyond last injection was 16 weeks (range: 8-28). Two eyes (15.4%) developed mild corneal epitheliopathy during the course of the treatment. CONCLUSIONS: Most eyes in this small series tolerated methotrexate injections without corneal toxicity. In eyes that developed epitheliopathy, the findings were mild and not treatment-limiting.

Desprendimiento de retina: la importancia del cribado de la agudeza visual / Retinal detachment: the importance of visual acuity screening

El desprendimiento de retina es una patología infrecuente en Pediatría y presenta diferencias con respecto a los casos que se dan en la edad adulta. Predomina en varones escolares. El subtipo más frecuente es el regmatógeno y la principal causa son los traumatismos, sin olvidar otras causas como las sindrómicas y lesiones no accidentales. El abordaje de esta patología es quirúrgico, aunque el éxito anatómico de la cirugía no implica buen resultado funcional. Presentamos el caso de un niño en el que se detectó una disminución unilateral importante de la agudeza visual en consulta programada (AU)

The retinal detachment is an infrequent pathology in pediatrics and presents differences with the cases that occur in adulthood. It predominates in school-age boys. The most frequent subtype is rhegmatogenous and the main cause is trauma, without forgetting other causes such as syndromic and non-accidental injuries. The approach to this pathology is surgical, although the anatomical success of the surgery does not imply a good functional result. We present the case of a child in whom a significant unilateral decrease in visual acuity was detected in a scheduled consultation (AU)

MACULAR HOLE ASSOCIATED WITH AGE-RELATED MACULAR DEGENERATION: Pathogenesis and Surgical Outcomes.

PURPOSE: To ascertain the pathogenesis of macular hole (MH) associated with age-related macular degeneration (AMD) and its surgical outcomes. METHODS: Patients with full-thickness MH associated with AMD (higher grades than intermediate) were enrolled. The mechanism of MH formation and closure rate after vitrectomy (surgical outcome) were determined using optical coherence tomography imaging. RESULTS: The mechanism of MH formation (35 eyes) associated with AMD was classified into four types: vitreomacular traction (42.9%), gradual retinal thinning caused by subretinal drusen or pigment epithelial detachment (22.9%), massive subretinal hemorrhage (20.0%), and combined (14.3%). In the 41 eyes that underwent vitrectomy, the logarithm of the minimum angle of resolution best-corrected visual acuity improved from 0.82 (0.10-2.30) preoperative to 0.69 (0.10-2.30) postoperative (P = 0.001). Successful closure of the MH was achieved in 33 eyes (80.5%) after vitrectomy. No significant association was observed between the closure rate of MH after vitrectomy and mechanism of MH formation (P = 0.083). CONCLUSION: The mechanism of MH formation associated with AMD was classified into four types and was not related to its surgical outcome. Considering visual improvement and surgical outcome after vitrectomy in our study, active surgical treatment can be considered for MH associated with AMD.

Management of a case of Enhanced S-cone syndrome with massive foveoschisis treated with pars plana vitrectomy with silicone oil tamponade.

Introduction: Goldmann Favre Syndrome (GFS) is a vitreoretinal degenerative disease with macular retinoschisis. The current treatment of foveoschisis is topical and oral carbonic anhydrase inhibitors.Case: A 22-year-old male diagnosed with GFS presented a progressive decrease in vision of the right eye. The optical coherence tomography showed a significant macular schisis. A medical treatment with topical and oral carbonic anhydrase inhibitors was ineffective. We performed a pars plana vitrectomy and silicone oil placement which led to an improvement of the visual acuity and a reduction of the foveoschisis.Conclusion: We describe here the first case of surgical treatment for macular schisis in a patient with GFS.

Chronic mild and acute severe glaucomatous neurodegeneration derived from silicone oil-induced ocular hypertension.

Recently, we established silicone oil-induced ocular hypertension (SOHU) mouse model with significant glaucomatous neurodegeneration. Here we characterize two additional variations of this model that simulate two distinct glaucoma types. The first is a chronic model produced by high frequency (HF) pupillary dilation after SO-induced pupillary block, which shows sustained moderate IOP elevation and corresponding slow, mild glaucomatous neurodegeneration. We also demonstrate that although SO removal quickly returns IOP to normal, the glaucomatous neurodegeneration continues to advance to a similar degree as in the HF group without SO removal. The second, an acute model created by no pupillary dilation (ND), shows a greatly elevated IOP and severe inner retina degeneration at an early time point. Therefore, by a straightforward dilation scheme, we extend our original SOHU model to recapitulate phenotypes of two major glaucoma forms, which will be invaluable for selecting neuroprotectants and elucidating their molecular mechanisms.

Difference in the efficacy of intravitreal dexamethasone implant before and after silicone oil removal: A case report.

RATIONALE: An intravitreal dexamethasone (IV-DEX) implant is safe and effective for the treatment of macular edemas; however, the efficacy of IV-DEX implants in silicone oil (SO)-filled eyes remains controversial. There is no previous study comparing an IV-DEX implant in the same eye with and without intravitreal SO. PATIENT CONCERNS: A 72-year-old man with proliferative diabetic retinopathy, macular edema, and rhegmatogenous retinal detachment, treated with pars plana vitrectomy with SO tamponade had refractory macular edema. DIAGNOSIS: Refractory macular edema. INTERVENTION: Subtenon triamcinolone injection, intravitreal anti-vascular endothelial growth factor injection, and IV-DEX implantation were performed; this was followed by intravitreal SO removal combined with IV-DEX implantation. OUTCOMES: The macular edema did not decrease significantly with posterior subtenon triamcinolone injection, intravitreal anti-vascular endothelial growth factor injection, and IV-DEX implantation; however, the edema was relieved after SO removal and a new IV-DEX implantation. LESSONS: IV-DEX implant may be less efficacious in the treatment of macular edema in an SO-filled eye than that in a normal vitreous cavity.

Case Report: Acute Retinal Necrosis after Intravitreal Ranibizumab for Exudative Macular Degeneration.

SIGNIFICANCE: Acute retinal necrosis (ARN) may occur after intravitreal ranibizumab (IVR) treatment for patients with exudative age-related macular degeneration (AMD). Awareness of this unusual but devastating complication after IVR is needed. Early identification may help provide timely antiviral treatment and prevent irreversible visual loss. PURPOSE: This study aimed to report a case of ARN after IVR in a patient with exudative AMD. CASE REPORT: A 67-year-old male patient complained of blurred vision in his left eye for 1 month. The patient was diagnosed with exudative AMD after detailed ophthalmic clinical evaluations. He received IVR once in his left eye. Three days after IVR, he developed varicella-zoster virus-associated ARN, which was treated with systemic and intravitreal antiviral therapy. Because of progressive inflammation, the patient underwent 25G pars plana vitrectomy with silicone oil tamponade. Seven months later, the patient was administered intravitreal aflibercept once in his left eye. Three months after intravitreal aflibercept, he underwent removal of silicone oil, and retinal detachment occurred 2 weeks after the surgery because of low IOP, and the patient eventually discontinued treatment. CONCLUSIONS: This study reports the first case of varicella-zoster virus-associated ARN after IVR. Early ARN may be very difficult to distinguish from intraocular inflammation after IVR. Therefore, early detection of viral DNA in the intraocular fluid using polymerase chain reaction is recommended. Immediate antiviral treatment may be beneficial to prevent severe visual loss.

Bilateral Necrotizing Retinitis following Encephalitis Caused by the Pseudorabies Virus Confirmed by Next-Generation Sequencing.

Purpose: The objective of this study was to report a case of bilateral necrotizing retinitis following viral encephalitis caused by the pseudorabies virus.Case report: A 49-year-old male had decreased bilateral visual acuity after the recovery of consciousness for one month. He had been in an unconsciousness status due to encephalitis for two months before the ocular symptoms developed. He was a pig slaughterer. Ocular ultrasound showed bilateral vitreous haze and retinal detachment. A vitrectomy and silicone oil tamponade were performed on the left eye. During surgery, massive periphery retinal necrosis appearing as a tattered fish net, and multiple retinal holes were observed. The pseudorabies virus was detected by next-generation sequencing in the vitreous specimen.Conclusion: The pseudorabies virus may cause bilateral necrotizing retinitis following viral encephalitis among those with close contact to pigs. Intraocular fluid provides a greater selection of samples and a longer time window for pathogenic detection.

Silicone oil in vitreoretinal surgery: indications, complications, new developments and alternative long-term tamponade agents.

Silicone oil (SO) has been used as a long-term tamponade agent in the treatment of complicated vitreoretinal diseases for about half a century, during which time many advances in surgical techniques and technologies have been made. This review summarizes the chemical and physical properties of SO, its indications and complications, including particularly emulsification. The mechanisms and risk factors for emulsification are discussed, as well as novel strategies for its effective removal. Finally, the review focuses on new improved formulations of SO, including research into slow-release pharmacological agents within SO and provides an overview of alternatives to SO for the purpose of long-term tamponade that are being developed.