Measurement of intraocular temperature in glaucoma: week-day and seasonal fluctuations

PURPOSE

To evaluate long-term intraocular temperature (IOT) variations in eyes with primary open-angle glaucoma (POAG) using an intraocular telemetric sensor.

METHODS

This prospective, open-label, multicentre observational study analysed the IOT variations in 22 eyes of 22 patients with POAG. All enrolled patients underwent implantation of an intraocular pressure (IOP) sensor during cataract surgery. The telemetric system uses a built-in temperature sensor to control measured IOP for temperature. Each time a patient measures their IOP, both the IOP and IOT are recorded in the reader device. Patients were instructed to self-measure their IOP as often as desired, but at least four times daily. Recorded readings were retrieved and analysed using mixed effect models and pairwise comparisons using Bonferroni correction to assess the statistical significance of average IOT variations between each individual weekday and calendar month.

RESULTS

The mean age of patients was 67.8±6.8 years and 36.4% were women. A total of 132 745 readings over 21 102 measurement-days were obtained. On average, IOT was significantly higher on Sundays (34.57°C; 95% CI 34.37 to 34.78) than on any other day of the week (p<0.001). Mean IOT on other weekdays ranged from 34.48°C to 34.51°C. Over the year, IOT followed a clear seasonal pattern, reaching its maximum in July (34.8°C; 95% CI 34.56 to 34.97) and its minimum in January (34.4°C; 95% CI 34.15 to 34.56; p<0.001).

CONCLUSIONS

This study demonstrates the feasibility of continual and long-term measurement of IOT using intraocular sensors. The results show significant short-term and long-term fluctuations of IOT. Research is warranted to understand the impact of IOT variations on IOP, ocular perfusion and glaucoma progression.

Erworbene Katarakte

Weitaus seltener und daher weniger bekannt als die altersbedingte Katarakt ist die sekundär erworbene Katarakt, die eine diagnostische und chirurgische Herausforderung darstellen kann. Dieser Beitrag gibt einen Überblick über die häufigsten Subtypen vor allem bei Erwachsenen und beleuchtet die chirurgischen Besonderheiten einschließlich perioperativer Charakteristika.

Erworbene Katarakte

Weitaus seltener und daher weniger bekannt als die altersbedingte Katarakt ist die sekundär erworbene Katarakt, die eine diagnostische und chirurgische Herausforderung darstellen kann. Dieser Beitrag gibt einen Überblick über die häufigsten Subtypen vor allem bei Erwachsenen und beleuchtet die chirurgischen Besonderheiten einschließlich perioperativer Charakteristika.

Influence of the scleral indentation technique on the re-detachment rate following retinal detachment surgery

Purpose

The aim of this study was to determine whether the choice of scleral indentation technique during primary rhegmatogenous retinal detachment surgery has an influence on the risk of re-detachment.

Methods

We included retrospectively 154 eyes with a primary rhegmatogenous retinal detachment treated in the Eye Clinic Sulzbach/Saar Germany, who were operated on by two experienced surgeons using the same basic surgical setup. Surgeon A performed an external 360° indentation, shaved the vitreous base using the light pipe cap, and used the operating microscope (opm) for direct visualization. Surgeon B performed an external 360° indentation, shaved the vitreous base using a simple indentor, and used an endoillumination (light pipe) with the opm and a handheld widefield lens for direct visualization.

Results

Comparing both indentation procedures, 15.66% (13/83) of patients operated on by surgeon A and 9.86% (7/71) of patients operated on by surgeon B had a retinal re-detachment within a follow-up period of 6 months (adj. p = 0.64, two-proportion Z-test).

Conclusion

The rate of retinal re-detachment could be influenced by the indentation technique at the end of surgery favoring external indentation and internal visualization with an endoilluminator (chandelier light). We attribute this to the better visualization of the vitreous base facilitated by endoillumination. However, many variables play a role in the development of retinal re-detachment, requiring further studies with a larger number of patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40942-022-00362-8.

What we already know:

Scleral indentation is widely recognized as an important step in rhegmatogenous retinal detachment surgery via pars-plana vitrectomy.

There are several surgical techniques for scleral indentation, however the procedures are neither standardized, nor have they ever been compared to one another to the best of our knowledge.

What this study adds:

This study shows that the rate of retinal re-detachment could be influenced by the indentation technique at the end of surgery favoring external indentation and internal visualization with an endoilluminator (chandelier light).

We attribute this to the better visualization of the vitreous base facilitated by endoillumination.

REVISED PREDICTIVE BIOMARKER FOR OCRIPLASMIN THERAPY IN VITREOMACULAR TRACTION DISORDERS

PURPOSE

To determine a statistically optimal limit of adhesion size in vitreomacular traction (VMT) syndrome for ocriplasmin treatment.

METHODS

In this retrospective, consecutive, interventional study, we included 106 patients treated with ocriplasmin injection because of VMT between July 2013 and January 2018. A univariate and multivariate risk analysis was performed with grouped factors and continuous factors. We used a receiver operating characteristic curve to measure the prognostic relevance of each continuous factor for therapy success and determined the statistically optimal cutoff value at which specificity and sensitivity are simultaneously maximized.

RESULTS

Among the grouped factors, only a phakic lens status showed a highly significant positive influence on the resolution of the VMT. For the continuous factors, only the adhesion diameter before injection was a good predictor of anatomical success. The statistically optimal threshold value for the adhesion size was calculated to be 480 µm. Eyes below this limit had a 6.84-fold better chance of VMT resolution compared with eyes with a larger adhesion diameter.

CONCLUSION

The threshold value of the VMT diameter for ocriplasmin therapy could be statistically defined as 480 µm and may thus be a new quantitative biomarker to predict treatment success.

Comparative cytotoxic and antiproliferative profile of methotrexate and fluorouracil on different ocular cells

PURPOSE

To analyse the cytotoxic and antiproliferative effect of methotrexate (MTX) and fluorouracil (5-FU) in vitro on fibroblasts, retinal pigment epithelial (RPE) and photoreceptor cells as an adjunct for reducing the incidence of proliferative vitreoretinopathy (PVR) after rhegmatogenous retinal detachment surgery.

METHODS

Methotrexate and 5-FU were dissolved separately in balanced salt solution (BSS) with concentrations ranging from 0-8000 µg/ml and 0-4000 µg/ml, respectively. All solutions were analysed in terms of pH and osmolarity and applied for 1 h to fibroblasts (BJ), RPE (ARPE-19) and photoreceptor (661W) cell lines adherently cultivated in 96-well cell culture plates (10 000 cells/well). 24 h after incubation, the proliferative (BrdU), metabolic (CellTiter-Glo) and apoptotic (Caspase 3/7) activity of the cells were examined in vitro.

RESULTS

5-FU had an antiproliferative effect on BJ and ARPE-19 cells starting from low concentrations (2 µg/ml). However, the viability of 661W cells decreased and apoptosis was induced with increasing 5-FU concentration. In contrast, MTX up to a concentration of 266 µg/ml did neither result in a significant loss of viability nor in increased caspase 3/7 activity of BJ, ARPE-19 and 661W cells and inhibited the proliferation of ARPE-19 already at low concentrations starting from 8 µg/ml.

CONCLUSIONS

Methotrexate dissolved in BSS is biocompatible up to a concentration of 266 µg/ml and may act as an intraoperative rinse solution to inhibit RPE proliferation in PVR-diseased eyes. Contrary, the use of 5-FU within the posterior segment of the eye is limited by its cell-damaging effect on photoreceptor cells.

Clinical results after single asymmetrical shark fin for graft orientation in DMEK

PURPOSE

Evaluating the effect of a single peripheral triangular mark to ensure the correct anterior-posterior graft orientation in DMEK.

METHODS

Retrospective study of patients scheduled for DMEK due to Fuchs endothelial dystrophy and divided into 2 study groups: Group -M (n = 184) had no mark of the EDM (Endothelial Descemet membrane) and group + M (n = 193) had a triangular peripheral mark. Follow-up time was 1 year after surgery.

RESULTS

The postoperative graft turning and Re-DMEK rate could be significantly reduced by the use of a peripheral mark (p = 0.002, p = 0.001, respectively). Re-DMEK due to primary graft failure was significantly associated with prior graft turning (p < 0.001). Both groups showed comparable values for visual acuity, central corneal thickness and endothelial cell count after a follow-up of 1 year.

CONCLUSION

Single peripheral triangular marking is a simple and cost-saving addition to EDM preparation to ensure the correct orientation of the graft intraoperatively and could lead to a significant reduction in graft turning and re-DMEK rate in this study.

Cleavage plane after liquid-bubble preparation of Descemet's membrane

PURPOSE

To investigate the ultrastructure of the cleavage plane of human cornea after liquid-bubble-prepared tissue for Descemet's membrane endothelial keratoplasty (DMEK).

METHODS

Experimental study with scanning electron microscopy (SEM) and block-face SEM of 18 corneal specimens. Fresh human research donor corneoscleral discs (n = 12) were prepared with liquid-bubble technique or examined as untreated controls (n = 3). In addition, Descemet's membrane samples, n = 3, were obtained in DMEK surgery.

RESULTS

The cleavage plane after liquid-bubble Descemet's membrane (DM) preparation was consistently located between interfacial matrix and posterior stromal collagen lamellae, providing a largely smooth surface exposing the amorphous interfacial zone without any significant amounts of adherent stromal remnants. No demarcation of a distinct pre-DM layer could be detected.

CONCLUSION

The DMEK graft preparation performed by liquid-bubble technique showed a smooth cleavage plane and could not reveal any demarcation of a distinct pre-DM layer.

Effectiveness of ocriplasmin in real-world settings: A systematic literature review, meta-analysis, and comparison with randomized trials

Purpose

Effectiveness of ocriplasmin for vitreomacular traction (VMT) varies depending on the presence of common ocular conditions and patient selection criteria. We carried out a systematic literature review and meta‐analysis of ocriplasmin studies conducted in real‐world settings (RWS) and compared outcomes with those from randomized controlled trials (RCTs).

Methods

We included prospective and retrospective studies from RWS documenting effectiveness of ocriplasmin in patients with VMT with or without MH, and RCTs of ocriplasmin versus control. Key end‐points were vitreomacular adhesion resolution (VMAR), nonsurgical MH closure, need for vitrectomy and safety. We conducted meta‐regression on pooled results to evaluate effects of baseline covariates and study design on outcomes.

Results

Thirty RWS (2402 patients) and 5 RCTs (737 patients) were included epiretinal membrane (ERM) and broad VMA were more prevalent in RCTs. Primary VMAR, vitrectomy and MH closure rates were comparable between RWS and RCTs. Rates of nsVMAR were significantly higher in RWS than RCTs (odds ratio 1.66; 95% confidence interval [CI]: 1.18–2.34). nsVMAR rates were inversely associated with ERM prevalence (odds ratio 0.20; 95% CI: 0.08–0.51). Compared with the recent OASIS trial, RWS reported a higher incidence of new/worsening subretinal fluid cases and less photophobia, photopsia, vitreous floaters, electroretinogram abnormalities and MH progression.

Conclusions

Ocriplasmin was significantly more effective in achieving nsVMAR in RWS than in RCTs. Lower ERM prevalence in RWS was the single significant explanatory variable for this difference. Conclusions on ocriplasmin safety in RWS are limited due to inconsistent reporting.

The impact of limbus detection, arcus lipoides and limbal vessels on the primary patency of clear cornea incisions in femtosecond laser-assisted cataract surgery

PURPOSE

To analyse the factors influencing the primary patency of clear corneal incisions in femtosecond laser-assisted cataract surgery (FLACS).

METHODS

In this prospective single-centre study, the graphical user interfaces of 159 patients undergoing femtosecond laser-assisted cataract surgery were documented by video. Subsequently, the quality of limbus detection along with the incidence of vessels and an arcus lipoides were assessed by a grading system and analysed in relation to the primary patency of the incisions. In particular, the differences between a superior and a temporal main incision were analysed.

RESULTS

The designed grading system could be applied in all cases without any problems. Limbus detection was highly inhomogeneous but had no influence on the patency of the incisions (46.3% poor, 18.4% moderate, 35.1% good). The characteristics of the arcus lipoides had little influence on the patency of the main incisions. Pronounced vascular ingrowth caused more tissue bridges but did not reduce the patency of the incisions. Temporal access was generally easier to open than a superior one (97.1% versus 88.9%).

CONCLUSION

We showed a patency rate of superior FLACS incisions of over 97% with the Femto LDV Z8 in our study. Temporal main incision is preferable to superior main incision in more difficult situations. The new grading system is suitable for further studies to provide information on the quality of the incision.

Selective Large-Area Retinal Pigment Epithelial Removal by Microsecond Laser in Preparation for Cell Therapy

Purpose

Cell therapy is a promising treatment for retinal pigment epithelium (RPE)-associated eye diseases such as age-related macular degeneration. Herein, selective microsecond laser irradiation targeting RPE cells was used for minimally invasive, large-area RPE removal in preparation for delivery of retinal cell therapeutics.

Methods

Ten rabbit eyes were exposed to laser pulses 8, 12, 16, and 20 µs in duration (wavelength, 532 nm; top-hat beam profile, 223 × 223 µm²). Post-irradiation retinal changes were assessed with fluorescein angiography (FA), indocyanine green angiography (ICGA), and optical coherence tomography (OCT). RPE viability was evaluated with an angiographic probit model. Following vitrectomy, a subretinal injection of balanced salt solution was performed over a lasered (maximum 13.6 mm2) and untreated control area. Bleb retinal detachment (bRD) morphology was then evaluated by intraoperative OCT.

Results

Within 1 hour after irradiation, laser lesions showed FA and ICGA leakage. OCT revealed that large-area laser damage was limited to the RPE. The angiographic median effective dose irradiation thresholds (ED50) were 45 µJ (90 mJ/cm2) at 8 µs, 52 µJ (104 mJ/cm2) at 12 µs, 59 µJ (118 mJ/cm2) at 16 µs, and 71 µJ (142 mJ/cm2) at 20 µs. Subretinal injection over the lasered area resulted in a controlled, shallow bRD rise, whereas control blebs were convex in shape, with less predictable spread.

Conclusions

Large-area, laser-based removal of host RPE without visible photoreceptor damage is possible and facilitates surgical retinal detachment.

Translational Relevance

Selective microsecond laser-based, large-area RPE removal prior to retinal cell therapy may reduce iatrogenic trauma.

Novel vitreous substitutes: the next frontier in vitreoretinal surgery

PURPOSE OF REVIEW

After removing the native vitreous during vitreoretinal surgery, an adequate substitute is required to ensure homeostasis of the eye. Current clinically used endotamponades (silicone oil, gases, semifluorinated alkanes) are effective in promoting retinal reattachment, but lead to complications such as emulsification, prolonged inflammation, blurred vision, raised intraocular pressure, cataract formation or the need for revision surgery. The aim of this review is to provide an update on novel vitreous substitutes with a focus on polymer-based systems.

RECENT FINDINGS

Polymeric hydrogels provide favourable properties such as high water content, optical transparency, suitable refractive indices and densities, adjustable rheological properties, injectability, biocompatibility and their ability to tamponade the retina via viscosity and swelling pressure, comparable to the native human vitreous body. Here, vitreous replacement strategies can be divided into chemically or physically crosslinked hydrogel systems that are applied as preformed or in-situ gelling matrices.

SUMMARY

Several hydrogel-based vitreous substitutes have already been positively evaluated in preclinical tests and have the potential to enter the clinical phase soon.

Functional and structural outcome after vitrectomy combined with subretinal rtPA Injection with or without additional intravitreal Bevacizumab injection for submacular hemorrhages

Background

To analyze the functional and anatomical outcome after vitrectomy with subretinal rtPA (recombinant tissue plasminogen activator) combined with or without an intravitreal Bevacizumab injection.

Patients and methods

Retrospective, consecutive case series of 31 pseudophakic patients with submacular hemorrhage (SMH) due to neovascular age-related macular degeneration (AMD) treated with vitrectomy, subretinal rtPA and pneumatic air displacement with or without an additional intravitreal Bevacizumab injection. The primary endpoints were best-corrected visual acuity (BCVA), and central macular thickness (CMT) measured by SD‑OCT. The secondary endpoint was a displacement of hemorrhage from the subretinal space three months after surgery.

Results

31 eyes of 31 patients were treated with vitrectomy and subretinal rtPA. 17/31 were treated simultaneously with an intravitreal Bevacizumab injection (group +B) and 14/31 without (group -B). The mean visual acuity improved significantly in both groups (from 1.37±0.39 to 1.03±0.57 logMAR in +B and from 1.48±0.48 to 1.01±0.38 logMAR in group –B, p<0.05). The mean CMT decreased in group +B from 607±179 μm to 424±205 μm (p = 0.2) and in group –B from 722±216 μm to 460±202 μm (p<0.05). A central displacement of the hemorrhage could be achieved in 47% in group +B, whereas in group -B displacement could be achieved in 50% (p = 0.44).

Conclusions

Vitrectomy with subretinal rtPA injection and air tamponade with or without simultaneous intravitreal Bevacizumab injection displaces SMH and improves BCVA effectively. In comparison, the postoperative outcome is comparable regardless of whether or not intravitreal bevacizumab is applied simultaneously.

[Postoperative endophthalmitis-a review of literature]

Postoperative endophthalmitis is one of the most feared complications for ophthalmologists, and the number of infections after intraocular procedures have been increasing. Nonetheless, a prompt intervention can result in the recovery of vision. In the past, endophthalmitis after cataract surgery was accountable for the majority of cases but is becoming less frequent due to the progress of surgical techniques and demographic developments with a steadily increasing number of intravitreal injections. In this article, the different forms of postoperative endophthalmitis are assessed in terms of pathophysiology and their specific characteristics depending on their etiology.

New optical coherence tomography grading system for macula-off rhegmatogenous retinal detachment: how off is off?

Background/Aims

The classification of retinal detachment is currently still based on many objective criteria such as duration of symptoms and funduscopic macular status, which leaves some important questions unanswered. The most important factor is the macular status, which is determined using direct or indirect ophthalmoscopy. Optical coherence tomography (OCT) has become a standard tool in clinical practice and enables detecting the exact extent of subretinal fluid in macula-off/on retinal detachment. We introduce a new and simple OCT-based grading system for macular detachment to provide a basis for further investigations to determine the optimal timing for surgery.

Methods

We retrospectively included 155 patients who were treated for retinal detachment. We defined the extent of the macular detachment in six stages based on the Early Treatment Diabetic Retinopathy Study (ETDRS) grid of the OCT scan.

The outermost ring of the ETDRS grid was defined as zone 1, the middle ring as zone 2 and the inner ring as zone 3. Only zone 3 differed in the retinal detachment height grades (grade a <250 µm vs grade b >250 µm). Retinal detachment heights that could not be measured were considered grade 4 (ungradable) detachments.

Results

Forty-seven patients had no macular involvement (grade 0). Regarding macular detachment, 14 patients had grade 1, 20 had grade 2, 9 had grade 3a, 29 had grade 3b and 36 had grade 4.

Conclusion

The newly developed OCT grading system for macular involvement following retinal detachment is a crucial tool to objectively classify a retinal detachment in order to be able to make better statements in the future, like for defining the optimal time for surgical intervention. A secondary benefit of this grading system would be that it improves predicting postoperative visual acuity.