To Örebro University

Purpose: To assess vision outcomes, risk of complications and whether age, gender, specific OCT changes and preoperative vision affect the prognosis for postoperative vision development. We seek to clarify the prognosis of LMH after surgery and assess whether complications can be reduced with appropriate management.

Methods: This retrospective study includes consecutive Lamellar Macular Hole (LMH) surgeries at Örebro University Hospital (2013– 2019), re-evaluated using the OCT-based consensus definition. Cases were classified as Epiretinal Membrane Foveoschisis (ERM-F) or LMH. Pre- and postoperative data were collected from medical records. Statistical analyses were performed with support from medical statisticians.

Results: Both the ERM-F and LMH groups showed Highly significant visual development (p-adj = 0.0010 and 0.0012 respectively), with a median visual improvement of 90% and 38%, respectively. Even the older LMH group, in which the majority (81%) exhibited pathological OCT findings, showed a median improvement of 61% and a significant visual improvement (adjusted p = 0.026).

Conclusion: The results indicate good potential for visual improvement in both groups. Even if the LMH group experiences positive vision improvement, these patients would experience further improvement without the aforementioned OCT changes. Early surgery is highly recommended, ideally before photoreceptor damage occurs; if already present, it should be performed as soon as possible to prevent further OCT pathology.

PURPOSE: This study reports clinical outcomes up to 6 years after Descemet's membrane endothelial keratoplasty (DMEK) performed at the Department of Ophthalmology, Örebro University Hospital, Örebro, Sweden.

METHODS: The study has a cross-sectional and case series design. Inclusion criteria were all DMEK-operated eyes during 2013-2018 until repeat keratoplasty.

RESULTS: Altogether 162 eyes from 120 patients were enrolled. Among eyes without preoperative comorbidities, examined 1-6 years after DMEK, 85.8% achieved visual acuity of 0.1 logMAR or better. The median endothelial cell density (ECD) loss was 27% in a cohort of eyes examined 1-2 years post-DMEK, 31% at 2-3 years, 42% at 3-4 years, and > 60% at 4-6 years post-DMEK. ECD at the examination timepoint was correlated with donor ECD (as expected) and time since surgery.

CONCLUSION: The results from DMEK surgeries in Örebro, Sweden, are promising. Further studies with even longer follow-up are needed to evaluate graft sustainability.

PURPOSE: The objective of this study was to evaluate the possibility of analysing quality indicators for uncomplicated primary rhegmatogenous retinal detachment in a hospital department of ophthalmology without the support of a national registry or need to collect data from referring ophthalmological centres.

METHODS: In 2014, we operated 231 consecutive eyes with uncomplicated retinal detachment. Our quality indicators were primary anatomical success, final anatomical success and postoperative endophthalmitis. We reviewed medical records in our university surgical department retrospectively and compared them with medical records from the regional hospitals that had referred most of the operated patients and done their own postoperative examination. Our hypothesis was that any retinal re-detachment and/or serious postoperative complication would be reported back.

RESULTS: The medical records at the surgical department revealed primary anatomic success for 91.3% of eyes and final anatomical success of 99.6%. The data from the regional hospitals confirmed that our hypothesis was correct. All patients with adverse outcomes were referred back for reoperation. Patients who were not referred again had an attached retina and showed no signs of endophthalmitis.

CONCLUSION: Our hypothesis that data in the surgical department's medical records would closely reflect those in referring hospitals was borne out. This supports, under current conditions, an effective strategy for analysing chosen quality indicators without relying on a national registry or reviewing records from regional hospitals.

PURPOSE: To develop a treatment model of rhegmatogenous retinal detachment (RRD) in which the effects of various vitreous tamponades can be explored.

METHODS: In a primary session, detachment was produced in the right eye of 24 rabbits using vitrectomy, posterior vitreous detachment, retinal break induction, and subretinal injection of viscoelastic solution. The following day, detachments were treated in 16 eyes using SF6 (n = 8) or Healaflow® (HF, a cross-linked hyaluronic acid hydrogel, n = 8) tamponade. Animals were followed for 1 month and thereafter examined macroscopically and morphologically in hematoxylin and eosin-stained sections.

RESULTS: Retinal detachment (RD) was successfully treated using repeated surgery. Two HF eyes developed progressive vitritis and were excluded from further evaluation. Enlargement of the initial retinal rupture with concomitant RD was seen in 4/8 SF6 eyes, while all 6 HF eyes displayed an attached retina. Attached areas showed a normal retinal morphology except for in 1 HF eye with extensive degeneration.

CONCLUSIONS: The RRD repeat vitrectomy model offers a possibility to explore the efficacy and complications of novel potential vitreous tamponades. Gel-based Healaflow® displays excellent anatomic reattachment, however, vitritis and retinal degeneration in some cases warrants further investigation.

PURPOSE: To describe the long-term results of surgical repair of patients with optic disc pit maculopathy (ODP-M).

METHODS: Prospective, consecutive, noncomparative follow-up study including 12 patients with ODP-M treated by pars plana vitrectomy (PPV), peeling of internal limiting membrane followed by gas tamponade. Subretinal fluid (SRF) was drained in 11 eyes through a retinotomy without laser photocoagulation. Preoperatively, macular detachment with retinoschisis was seen in 9 out of 12 eyes with three eyes having only subretinal fluid in the macular area. The median age at surgery was 20 years (range 9-60 years).

RESULTS: Follow-up time from initial surgery was 63 months (median). Eight eyes were anatomically reattached after one operation without remaining SRF in the macula. Two patients required a reoperation due to leakage from the retinotomy and another two underwent a second PPV procedure due to late recurrences. Successful healing was at follow-up control observed in 11 of 12 eyes. There was no statistically significant difference in visual acuity between patients before and after surgery (p = 0.24). Central visual field defects with depressed mean deviation were detected in all treated eyes.

CONCLUSION: In this long-term study of ODP-M final outcome regarding healing was relatively efficacious, however, a relatively large proportion had complications associated to retinotomies. We conclude that drainage of SRF should likely be avoided since it appears to contribute little to the resorption rate of SRF and seems to linked to unnecessary risks.

PURPOSE: To investigate the inflammatory response of current and future potential vitreous substitutes in an experimental in vivo vitrectomy model.

METHODS: Twenty-five gauge pars plana vitrectomy was performed in the right eye of 60 pigmented rabbits, with subsequent injection of 0.5-1.0 ml of Healaflow® (cross-linked hyaluronic acid, n = 12), Bio-Alcamid® (polyalkylimide, n = 8), silicone oil (n = 12), or balanced saline solution (BSS, n = 28). Postoperative clinical evaluation was performed; and the rabbits were sacrificed at 1 day, 1 week, or 1 month. The eyecups were then examined macroscopically; the retinas sectioned and stained with hematoxylin and eosin (Htx), and immunohistochemically labeled for glial fibrillary acidic protein (GFAP), CD45, galectin-3, CD68, and CD20. Unoperated left eyes from treated animals as well as eyes from untreated animals were used as controls.

RESULTS: Vitrectomy without major complications was achieved in 46/60 eyes. The remaining 14 eyes were analyzed separately. One eye developed endophthalmitis after 1 week and was excluded. Eyes treated with Healaflow®, silicone oil, and BSS had a comparable appearance macroscopically and in Htx-stained sections, whereas Bio-Alcamid®-injected eyes exhibited increased macroscopic inflammation and severely affected retinas. GFAP upregulation was present in all treatment groups, most prominent in eyes treated with Bio-Alcamid® and silicone oil. Upregulation of CD45 and CD68 in the inner retina and vitreous space was most prominent with Bio-Alcamid® treatment, and these eyes together with their silicone oil-treated counterparts also displayed a stronger upregulation of CD20-labeled cells compared with remaining groups. General upregulation of galectin-3, mainly in the inner retina, was found in all groups. In eyes with perioperative complications, labeling of CD45, CD68, and especially GFAP was comparably high.

CONCLUSIONS: We here describe differences in the postsurgery inflammatory profiles of existing and potential vitreous substitutes. Bio-Alcamid® and silicone oil display severe signs of gliosis and inflammation, whereas Healaflow® elicits minimal reactions comparable with BSS, highlighting its potential application as a vitreous substitute in a future clinical setting.

BACKGROUND: To report beta-trace protein (βTP) levels in the subretinal fluid (SRF) of four patients with a macular detachment associated with optic disc pit (ODP).

METHODS: Four patients with a serous retinal detachment involving the macula was operated by pars plana vitrectomy (PPV) with C2 F6 gas tamponade and peeling of internal limiting membrane (ILM). Patients with a follow-up period exceeding one year postoperatively were included in the study. The SRF was drained using a fine cannula without laser photocoagulation, and the samples were analysed using particle-enhancing nephelometry. The levels of βTP were compared to 20 routine cerebrospinal fluid (CSF) samples.

RESULTS: In four of the five samples from SRF had relatively low βTP levels, with a mean concentration of 6.6 mg/l (range 2.0 to 23.1 mg/l) compared to 16.0 mg/l (range 6.3-26.8 mg/l) in CSF. The only SRF sample within the range corresponding to normal CSF was the first sample from patient 4, and the analysis of the renewed aspirate during the second operation was 2.8 mg/l. Postoperatively, the regression of SRF was slow, but regression of SRF in the foveal region took place in all cases; however, visual acuity (VA) was improved in only half of the patients.

CONCLUSION: The results from the analysed SRF regarding βTP concentration in these patients indicate that the SRF in ODP is not identical to CSF, as the concentrations of βTP differ.

Purpose: Vitrectomy requires the substitution of the natural vitreous, as well as tamponading of retinal breaks. Clinically available alternatives such as gas and silicone oil have side effects such as inflammation, secondary glaucoma, cataract, and a need for head posturing. In this study, a hydrogel of cross-linked sodium hyaluronic acid (Healaflow(®)) is evaluated for use as a novel vitreous substitute.

Methods: A combined 25-20-gauge pars plana vitrectomy with posterior vitreous detachment was performed in the right eye of twelve pigmented rabbits, with subsequent injection of approximately 1 ml Healaflow(®). Clinical evaluation, measurement of intraocular pressure (IOP), and full-field ERG were performed postoperatively. The rabbits were sacrificed at different time-points between 42 and 105 days. After enucleation, the eyes were examined macroscopically, photographed, and prepared for histological examination with routine microscopy and immunohistochemistry.

Results: Healaflow(®) was successfully used with standard surgical procedures and remained translucent but did lose most of its viscosity during the postoperative period. One rabbit was lost due to unrelated causes. In two eyes iatrogenic partial retinal detachments were seen, and in two eyes significant cataract developed due to intra-operative complications. ERG-recordings revealed no toxic effect on rod or cone function. Routine microscopy and immunohistochemistry demonstrated normal morphology with some Müller cell activation (up-regulation of glial acidic fibrillary protein, GFAP) compared to unoperated eyes and no significant DNA-fragmentation (TUNEL-assay).

Conclusions: Healaflow® did not affect retinal morphology or function negatively during long-term use as a vitreous substitute, making it highly interesting in this setting. An estimated retention time of a few weeks suggests potential for use as a short-term tamponade. Future work will include an increased ratio of cross-linking to prolong the structural integrity of the gel.

Purpose: To describe a new model for in vitro assessment of novel vitreous substitute candidates.

Methods: The biological impact of three vitreous substitute candidates was explored in a retinal explant culture model; a polyalkylimide hydrogel (Bio-Alcamid (R)), a two component hydrogel of 20 wt.% poly (ethylene glycol) in phosphate buffered saline (PEG) and a cross-linked sodium hyaluronic acid hydrogel (Healaflow (R)). The gels where applied to explanted adult rat retinas and then kept in culture for 2, 5 and 10 days. Gel-exposed explants were compared with explants incubated under standard tissue culture conditions. Cryosections of the specimens were stained with hematoxylin and eosin, immunohistochemical markers (GFAP, Vimentin, Neurofilament 160, PKC, Rhodopsin) and TUNEL.

Results: Explants kept under standard conditions as well as PEG-exposed explants displayed disruption of retinal layers with moderate pyknosis of all neurons. They also displayed moderate labeling of apoptotic cells. Bio-Alcamid (R)-exposed explants displayed severe thinning and disruption of retinal layers with massive cell death. Healaflow (R)-treated explants displayed normal retinal lamination with significantly better preservation of retinal neurons compared with control specimens, and almost no signs of apoptosis. Retinas exposed to Healaflow (R) and retinas kept under standard conditions showed variable labeling of GFAP with generally low expression and some areas of upregulation. PEG-exposed retinas showed increased GFAP labeling and Bio-Alcamid (R)-exposed retinas showed sparse labeling of GFAP.

Conclusions: Research into novel vitreous substitutes has important implications for both medical and surgical vitreoretinal disease. The in vitro model presented here provides a method of biocompatibility testing prior to more costly and cumbersome in vivo experiments. The explant culture system imposes reactions within the retina including disruption of layers, cell death and gliosis, and the progression of these reactions can be used for comparison of vitreous substitute candidates. Bio-Alcamid (R) had strong adverse effects on the retina which is consistent with results of prior in vivo trials. PEG gel elicits reactions similar to the control retinas whereas Healaflow (R) shows protection from culture-induced trauma indicating favorable biocompatibility.