International Olympic Committee (IOC) consensus paper on sports-related ophthalmology issues in elite sports

Vision plays an important role in an athletes' success. In sports, nearly 80% of perceptual input is visual, and eye health and sports medicine are closely intertwined fields of utmost importance to athletes. The physical nature of sports activities renders individuals more prone to various eye injuries than the general population. Ocular trauma can lead to lifelong sequelae, and impaired vision requires careful follow-up and management. Apart from injuries, athletes may also experience vision problems that can hamper their performance, including blurred vision, double vision, and light sensitivity. The interdisciplinary nature of sports medicine necessitates collaboration between sports medicine professionals and ophthalmologists. Through such collaborations, athletes can receive appropriate eye care, education on proper eye protection and guidance on adopting good eye health practices. If any inconspicuous symptoms are not detected and treated promptly, athletes may acquire systemic injuries because of defective vision, preventing them from achieving high level athletic performance in competitions. The protection of the elite athlete is the responsibility of all of us in sports medicine. To advance a more unified, evidence-informed approach to ophthalmic health assessment and management in athletes and as relevant for sports medicine physicians, the International Olympic Committee Consensus Group aims for a critical evaluation of the current state of the science and practice of ophthalmologic issues and illness in high-level sports, and present recommendations for a unified approach to this important issue.

Retinal surgery quality indicators for uncomplicated primary rhegmatogenous retinal detachment without a national registry

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.

A prospective long-term follow-up study of optic disc pit maculopathy treated with pars plana vitrectomy, drainage of subretinal fluid and peeling of internal limiting membrane

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.

A New Retinal Detachment Treatment Model for Evaluation of Vitreous Tamponades

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.

Preoperative preparation of eye with chlorhexidine solution significantly reduces bacterial load prior to 23-gauge vitrectomy in Swedish health care

Background

Bacteria in the conjunctiva present a potential risk of vitreous cavity infection during 23-gauge pars plana vitrectomy (PPV). Current preoperative procedures used in Sweden include irrigation with chlorhexidine solution (CHX) 0.05% only and no iodine solutions. We evaluated the bacterial diversity and load before and after this single antibacterial measure.

Methods

In a prospective, consecutive cohort we investigated bacterial growth in samples from 40 eyes in 39 consecutive individuals subjected to vitrectomy. A conjunctival specimen was collected from each preoperative patient before and after irrigating of eye with CHX, 0.05% solution. Iodine was not used during any part of the surgery. One drop of chloramphenicol was administered prior to surgery. Samples from vitreous cavity were collected at the beginning and end of vitrectomy. All conjunctival specimens were cultured for different species and quantified using colony forming units (CFU).

Results

There was a significant 82% reduction in the total number of CFUs for all bacteria in all eyes (P < 0.0001), and 90% reduction for coagulase negative staphylococci (CoNS) alone (P = 0.0002). The number of eyes with positive bacterial growth in conjunctival samples decreased from 33 to 18 after irrigation with CHX (P = 0.0023). The most common bacteria prior to surgery were CoNS (70%), Propionibacterium acnes (55%) and Corynebacterium species (36%). No case of post-vitrectomy endophthalmitis was reported during mean follow-up time, which was 4.6 ± 2.3 (range; 1.5 to 9) months.

Conclusions

Patients undergoing PPV harbored bacteria in conjunctiva capable of causing post-vitrectomy endophthalmitis. Preoperative preparation with CHX significantly reduced the bacterial load in the conjunctival samples subsequently leading to very low inoculation rates in recovered vitreous samples. Thus, CHX used as a single disinfectant agent might be an effective preoperative procedure for eye surgery in Sweden. This is a relatively small study but the results could be a reference for other intraocular surgeries.

Levels of beta-trace protein in optic disc pit with macular detachment

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 C₂F₆ 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.

[Floorball – a common cause of sport related eye injury]

Floorball - a common cause of sport related eye injury The aim of this study was to survey the incidence and type of sport related to eye injuries with special interest in floorball. A prospective study was conducted December 1st 2013 through November 30th 2014 at the Department of Ophthalmology, Örebro University Hospital. All patients presenting with an acute sports related eye injury were offered to be included. Information was collected from a self-administered questionnaire and from medical journals. During the study period, 49 patients sought care for sports related eye injuries, and 26 (53%) of those were related to floorball. The number of patients who agreed to take part in the study was 38, of which 25 had injuries related to floorball. Among the floorball players, there were two patients where the injury caused permanent vision impairment. None of the floorball players wore eye protection at the time of injury. According to this study, protective eyewear should be recommended when playing floorball, regardless of age or setting.

The efficiency of cross-linking methods in eradication of bacteria is influenced by the riboflavin concentration and the irradiation time of ultraviolet light

PURPOSE

To determine bacterial eradication using numerous riboflavin concentrations and different ultraviolet light A (UVA) radiant and exposure time in an experimental model.

METHODS

Dilutions of Staphylococcus epidermidis were mixed with riboflavin at varying concentrations (0.007–0.09%). Effects on bacterial growth were evaluated after 0, 3, 6, 30 and 60 min of UVA exposure (irradiance 30 and 3 mW/cm2). Standard settings of UVA were compared with high-power UVA approach. Different fluid thicknesses of the exposed dilutions were also examined to improve the model.

RESULTS

Bacterial eradication (%) was increased after 60 compared with 30 min of UVA exposure for concentrations of 0.03–0.07% but not for 0.09% riboflavin.There was a significant difference between the efficacy between 0.03 and 0.09% and eradication dropped from 80%to 50%(p = 0.01).A correlation could be calculated for the amount of riboflavin at 60 min of UVA and the ability to kill bacteria(p = 0.01). The antibacterial effect was more pronounced when the tested bacterial suspension thickness was reduced. High-power UVA method was less potent in microbial elimination, eradicating only 60%of bacteria after 6 min versus 97–99%after 60 min in the low-power setting, compared with respective controls (p = 0.02).

CONCLUSIONS

In these in vitro experiments, a longer UVA exposure time in combination with lower riboflavin levels were found to be favourable in killing bacteria as compared to the standard cross-linking settings. Further studies are needed to evaluate the clinical relevance of these findings.

Comparison of UVA- and UVA/riboflavin-induced growth inhibition of Acanthamoeba castellanii

PURPOSE

To investigate whether ultraviolet light (UVA) at 365 nm can inhibit/eliminate Acanthamoeba growth and if riboflavin would potentiate such an association.

METHODS

Acanthamoeba castellanii in a fluid medium with a concentration of approximately 1.7 × 10(4) protozoa/ml were prepared with (0.01 %) and without riboflavin. Exposure of UVA (dose 5.475 J/cm(2)) took place twice, with each illumination period followed by culturing of 10 μl in peptone yeast-extract glucose (PYG) medium for 7 days. Every suspension prepared had a non-exposed control solution. Determination of Acanthamoeba was conducted daily, by count in Burker chamber days 4 through 7 after exposure. Statistical analysis was done by repeated-measurement ANOVA and post-hoc analysis for unpaired samples.

RESULTS

The exposure of ultraviolet light resulted in an inhibited growth of Acanthamoeba compared to the non-exposed solutions, with a statistically significant reduction over time (p = 0.0003). The addition of riboflavin did not amplify the effect, and there were no tendencies for an interaction effect between UVA and riboflavin.

CONCLUSIONS

The antiprotozoal effect of the UVA wavelength, utilized in CXL, is solely mediated by ultraviolet light, and riboflavin does not seem to amplify the antimicrobial efficacy.

Experts do not agree when to treat retinopathy of prematurity based on plus disease

OBJECTIVES

To investigate inter-reader agreement on five severity levels of central vascular changes (none, mild, moderate, severe pre-plus disease, plus disease) and aggressive posterior retinopathy of prematurity (ROP), and to see whether an unintended shift in indication for treatment occurred.

METHODS

Four international ROP readers participated. Before the grading of the photographs, the readers were informed that a high proportion of advanced ROP cases were included. In total, 243 photographs/948 quadrants were available from 136 infants. As a standard series of photographs was available, grading was performed under optimised conditions.

RESULTS

The four readers agreed on the quadrant scores of only 70 (7.38%) of the 948 quadrants--that is, on 1, 5, 15, 4 and 45 quadrants for scores 0, 1, 2, 3 and 4, respectively. The mean scores differed systematically between the readers (permutation test, p<0.0001). Agreement on presence of aggressive posterior ROP from all four readers was not obtained for any of the photographs. Readers scored plus disease in at least two quadrants in 95.5% of the eyes for which treatment was indicated. All four readers agreed on the scoring of indication for treatment for 195 eyes (80.2%); however, treatment was only recommended in 18 (7.4%) eyes. One reader was found to differ systematically from the others in indicating treatment (Rasch analysis; p=0.0001). Finally, a significant shift in indication for treatment occurred between birth period 2000-2002 and 2003-2006 (Mann-Whitney rank sum test, p<0.001).

CONCLUSIONS

Inter-reader agreement on central vascular changes is poor, especially when based on more than two rating categories. The subjective nature of diagnosing such vascular changes possibly resulted in earlier treatment of preterm infants in Denmark over the entire study period (1997-2006). The recent increased incidence of treated infants in Denmark is, at least in part, explained by a significant shift in indication for treatment.

Longterm follow-up of pars plana vitrectomy for vitreous floaters: complications, outcomes and patient satisfaction

PURPOSE

Floaters caused by degenerative or postoperative changes in the vitreous can interfere with all aspects of visual functioning. The aim of this study is to report the longterm outcome of pars plana vitrectomy (PPV) for persistent vitreous opacities.

METHODS

In a retrospective, non-randomized, interventional case study we reviewed all cases of vitreous floaters that were vitrectomized at our department between 1997 and 2006. Patient complaints and satisfaction were assessed by a questionnaire administered at the end of follow-up.

RESULTS

Seventy-three consecutive cases were included (61 patients). Mean Snellen best corrected visual acuity (BCVA) before surgery was 0.81. Overall, 85% of patients complained of severe or very severe difficulty caused by floaters. A total of 42% of eyes were pseudophakic, four of which were operated with combined PPV and phacoemulsification. Mean follow-up time was 37 months. Of the phakic eyes, 60% were operated for cataract during follow-up. One retinal detachment (RD) occurred immediately postoperatively (1.3%) and another four eyes developed RD during longterm follow-up 24-44 months after PPV (5.5% of cases). Postoperative BCVA remained mostly unchanged. Overall, 88% of patients were satisfied with the results of the operation.

CONCLUSIONS

Some patients make considerable complaints as a result of vitreous opacities and their distress does not correlate with visual acuity. Vitrectomy is a safe and effective procedure with which to help these patients. Patients should be informed about the risk of cataract progression, unexpected inflammatory reaction and an increased risk for RD several years after PPV (5.5%).

Evaluation of viscoelastic poly(ethylene glycol) sols as vitreous substitutes in an experimental vitrectomy model in rabbits

The aim of this study was to employ an experimental protocol for in vivo evaluation of sols of 5 wt.% poly(ethylene glycol) (PEG) in phosphate-buffered saline as artificial vitreous substitutes. A 20 gauge pars plana vitrectomy and posterior vitreous detachment were performed in the right eye of eight pigmented rabbits. Approximately 1 ml of the viscoelastic PEG sols was then injected into the vitreous space of six eyes. PEG with an average molecular weight of 300,000 and 400,000 g mol(-1) was used in two and four eyes, respectively. Two eyes received balanced salt solution and served as controls. Full-field electroretinography was carried out and intra-ocular pressure (IOP, palpation) measured pre- and post-operatively at regular intervals up to 41 days. The rabbits were killed and the eyes examined by retinal photography, gross macroscopic examination and histology. The viscoelastic sols were successfully injected and remained translucent throughout the post-operative period, with some inferior formation of precipitates. None of the eyes displayed IOP elevation post-operatively, but in three of the PEG sol injected eyes transient hypotony was noted. One eye sustained retinal detachment during surgery and another two in the post-operative period. ERG recordings confirmed preservation of retinal function in three out of four eyes injected with 400,000 g mol(-1) PEG. Histological examination revealed up-regulation of glial acidic fibrillary protein in Müller cells in PEG sol injected eyes, but normal overall morphology in eyes with attached retinas. The viscosity of the sol was not retained throughout the post-operative period, indicating the demand for polymer cross-linking to increase residence time. The results provide promising preliminary results on the use of PEG hydrogels as a vitreous substitute.

Vasoproliferative retinal tumours in a Swedish population

PURPOSE

To describe the clinical appearance and the visual outcome of a cohort of patients with vasoproliferative retinal tumours (VPRTs) that were diagnosed and treated between 2002 and 2007 at the University Hospital of Örebro.

METHODS

Nine patients with diagnosed VPRTs were included in a retrospective study. The mean age at the time of diagnosis was 50.2 years (range 7-74 years). Follow-up time ranged between 14 and 83 months (mean 42.6). Nine out of ten eyes received cryotherapy; six eyes were also treated with photocoagulation. One patient was treated with intravitreal injections of ranibizumab (Lucentis(®)) and another was referred for brachytherapy. Because of persisting macular oedema, one eye was treated with intravitreal injection of triamcinolon.

RESULTS

Of the treated eyes, one had anterior uveitis, six had macular oedema at baseline and four had an exudative retinal detachment at the time of diagnosis. Seven eyes underwent vitrectomy because of epiretinal membranes. Visual acuity at diagnosis was 0.21 (mean) (range 0.02-0.6) and at latest check-up 0.30 (mean) (range light perception (LP)-1.0), with improvement in six eyes and deterioration in two. Two out of four patients with retinal detachment were successfully treated surgically.

CONCLUSION

VPRTs are benign intraretinal changes. Several complications are associated with this condition. All patients in this study had symptom-giving tumours and six patients (six eyes) already had profound macular oedema at presentation. In these cases, when complications have already developed, the final visual prognosis is poor, thereby making it important to detect these tumours early. The patient who received anti-vascular endothelial growth factor (VEGF; Lucentis) therapy showed a slow improvement and distinct regression in exudations during the follow-up time. However, no increase in visual acuity was seen. At latest examination a peripheral exudative retinal detachment was still observed. Whether anti-VEGF treatment is effective, as either an alternative or complementary therapy, must be established in the future.

Electroporation therapy of skin cancer in the head and neck area

BACKGROUND

Electroporation therapy is a new cancer treatment modality in which a locally applied electrical field enhances cell membrane permeability, allowing greater intracellular accumulation of a chemotherapeutic agent.

OBJECTIVE

To evaluate the efficacy of electroporation therapy in treating basal cell and squamous cell carcinomas of the skin.

MATERIALS AND METHODS

Six patients with skin cancer of the head and neck were treated using electroporation therapy with intratumorally injected bleomycin. Orbital growth, facial nerve proximity, or proximity to cartilage of the external meatus complicated four of these tumors. The intention was curative. The follow-up period was 24 months and included biopsies after 8 weeks.

RESULTS

In four of the six patients, one treatment was enough to eradicate the tumor. In one patient, the tumor persisted even after a second treatment with electroporation therapy. A septal cartilage perforation was the only major complication. The cosmetic results were very satisfactory. One additional recurrence was recorded 6 months after the follow-up period

CONCLUSION

Electroporation therapy is a promising new cancer treatment that should be further evaluated as an alternative to surgery, especially in complicated skin cancer.

Evaluation of antibacterial efficacy of photo-activated riboflavin using ultraviolet light (UVA)

BACKGROUND

To evaluate the antibacterial efficacy of photo-activated riboflavin using Ultraviolet A (UVA) on three bacterial strains commonly detected in keratitis.

METHODS

Three bacterial strains (Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa) were cultured on blood/hematin-agar plates and dispersed in PBS. Dispersion was done of 10 microl of bacterial stock-solutions in 90 microl of RPMI, where different riboflavin molarities had been added, to achieve a bacterial concentration of 1-4 x 10 (4)/ml. Riboflavin end molarities before illumination were 0, 100, 200, 300 and 400 microM. Each solution had a negative control. The solutions were illuminated with UVA (365 nm) for 30 minutes (5.4 J/cm(2)) and then continued for a total time of 60 minutes (10.8 J/cm(2)). A count of CFU was conducted after incubation and results compared.

RESULTS

In all tested strains, a slight decrease of bacteria was seen when exposed to UV for 30 minutes. A doubling of the UV dose showed a marked decrease of bacterial count in all bacteria tested. The combination of UV and riboflavin showed a more extensive reduction of CFU, confirming an interaction effect between UV and riboflavin.

CONCLUSION

Riboflavin photo-activation using UVA (365 nm) can achieve an extensive eradication of bacteria, and the combination is more potent in reducing bacterial number than UV alone.

Follow-up of 15 children with severe ROP 1987-1989

Between 1987-89 fifteen premature infants with severe retinopathy of prematurity (ROP), at the age of ten months or less, were admitted as outpatients to the Department of Ophthalmology at the Orebro Medical Center Hospital. Initial examination of the infants showed that 6 eyes had stage 3+, 3 eyes had stage 4B and 21 eyes had stage 5 ROP. All 15 infants were born at gestational week 24-28 (mean value 26) and had a birth weight between 600 and 1310 g (mean 907 g). For stage 3+ cryotherapy was performed. For stage 4B and 5 buckling procedure and vitreous surgery was performed in an attempt to re-attach the retina. The children were followed 2-5.5 years. Postoperatively, the retinas of all eyes in stage 3+ and 4B were attached. Four retinas out of seventeen stage 5 eyes were later found to be centrally re-attached. One eye with stage 3+ and four eyes with stage 5 were not treated at all. At follow-up of stage 3+ and 4B, visual acuity was measurable in all eyes; in stage 5 only two out of four eyes with anatomically reattached retinas had perception of light.

Sheathotomy in complicated cases of branch retinal vein occlusion

PURPOSE

To report the clinical experience and results of using a microsurgical technique to decompress the arteriovenous connection in complicated branch retinal vein occlusion (BRVO) combined with haemorrhage, oedema and ischaemia.

METHODS

We carried out a retrospective, non-randomized, interventional case study of the surgical sheathotomy decompression procedure. We enrolled 12 patients (seven women, five men; median age 64 years) with BRVO and decreased visual acuity (VA) caused by haemorrhage, oedema and ischaemia. The mean duration of thrombosis was 7 months (2-15 months). The patients were examined for pre- and postoperative best corrected VA (BCVA), intraocular pressure (IOP) and fundus photography. Ten patients were examined with fluorescein angiography and eight with ocular coherence tomography (OCT). Postoperative progression of cataract was recorded, as were other complications. The mean follow-up time was 20 months (8-39 months).

RESULTS

Best corrected VA had improved in nine patients, was unchanged in one patient and had deteriorated in two patients at the last follow-up. Noted complications were venous haemorrhage at surgery in five patients, retinal detachment in one patient and progression of cataract in four patients.

CONCLUSIONS

Microsurgical treatment with sheathotomy of BRVO is a technically feasible procedure with few complications. Postoperative increased reperfusion could explain the resolution of macular haemorrhage, oedema and ischaemia, and may improve visual function in patients with this common vascular eye disease.

Photoreceptor survival in transplantation of autologous iris pigment epithelial cells to the subretinal space

PURPOSE

To investigate photoreceptor survival in transplantation of non-cultured iris pigment epithelial (IPE) cells to the subretinal space in a prospective experimental study.

METHODS

Upper iridectomies were carried out in the right eyes of 37 pigmented rabbits. Suspensions of freshly harvested autologous IPE cells (without culturing) were prepared and injected into the subretinal space of the same eye. Follow-up examinations were carried out using ophthalmoscopy and colour fundus photography. The rabbits were killed at 1, 2, 3 and 6 months, respectively, and the eyes examined with light and electron microscopy.

RESULTS

On histological examination, the photoreceptor cells were found to be well-preserved in grafted areas at 1-3 months. At 6 months, the photoreceptors generally disclosed a normal nuclear layer and long outer segments when overlying areas with single cells or clusters of transplanted IPE cells. Multilayers of cells in abundance, including native RPE cells and macrophages (stained with RAM 11), particularly under microfolds of the neural retina, were occasionally associated with photoreceptor damage and nuclear drop out from the outer retinal layer. There was no inflammatory response in the choroid and the choriocapillaris remained patent.

CONCLUSION

The experiments show that grafting freshly harvested autologous IPE cells to the subretinal space is feasible and that the photoreceptors generally survive for at least 6 months when overlying the transplanted areas. Multilayers of abundant cells in the subretinal space may induce adverse focal effects on adjacent photoreceptors.

The Swedish national survey of surgical excision for submacular choroidal neovascularization (CNV)

PURPOSE

To compare the visual outcome after surgical removal of subfoveal choroidal neovascularization (CNV) in patients younger and older than 50 years of age.

METHODS

Patient records from all Swedish centers performing submacular CNV surgery were reviewed and 90 patients treated between 1992-1999 with a follow-up of 6 months or more were included. The results obtained in 49 patients aged 51-89 years (median=72 years) with neovascular disease caused by age-related macular degeneration (AMD) were compared with the outcome of 41 patients aged 6-49 years (median=36 years) with CNV secondary to non-AMD causes. The main outcome measure was the improvement or deterioration in visual acuity (standardized in logMAR units) at 6 months following surgery. Secondary endpoints were recurrent CNV and surgical complications.

RESULTS

The level of preoperative visual acuity was not significantly different between younger patients with CNV associated with non-AMD and older patients with visual loss due to AMD (p=0.069). However, visual acuity at 6 months after surgery was better (p=0.0042) in younger patients (median improvement=0.19 logMAR) than in older patients (median improvement=0.0 log MAR). Marked visual improvement (>1 log MAR unit) was seen in 29% of non-AMD patients <50 years compared to 0% in the AMD group >50 years.

CONCLUSION

Surgical removal of submacular CNV does not appear to improve visual acuity in patients > 50 years of age. However, it may be beneficial for younger patients where a substantial improvement of visual acuity is seen in a subset of these patients. Further studies are required to assess the long-term outcome.

Experimental transplantation of autologous iris pigment epithelial cells to the subretinal space

PURPOSE

To investigate the cellular morphology in the subretinal space following transplantation of iris pigment epithelial (IPE) cells from the same eye.

METHODS

Following an iridectomy, fresh IPE cells were prepared and no culturing performed. After pars plana vitrectomy, a suspension of autologous IPE cells was injected into the subretinal space in 37 rabbits. The grafts were monitored by ophthalmoscopy and colour fundus photography. Rabbits were sacrificed at 1, 2, 3 and 6 months, respectively, and the eyes examined with light and electron microscopy.

RESULTS

The grafted area retained the same configuration over 6 months but then appeared less pigmented. At 1-3 months, the IPE formed one or more contiguous layers on top of native RPE. At 6 months, cells compatible with grafted IPE were present in the subretinal space, often forming monolayer-like chains integrating with the native RPE. Depigmented cells of presumed IPE origin were seen and frequently in association with abundant melanin granules located in the apical portion of adjacent RPE cells. In such areas, large macrophage-like cells were observed.

CONCLUSION

Transplanted IPE cells survived for up to 6 months in the subretinal space. Our observations suggest a scenario of remodelling of the cellular layers in the subretinal space over time where grafted IPE cells formed a compound layer with the native RPE. Transplantation of autologous IPE cells may have a potential as a treatment modality in selected cases of age-related macular degeneration.

Cellular migration into neural retina following implantation of melanin granules in the subretinal space

BACKGROUND

In some retinal diseases and following transplantation of retinal pigment epithelium (RPE), melanin granules are liberated to the subretinal space. Our aim was to investigate the cellular response to implanted extracellular melanin.

METHODS

After pars plana vitrectomy, 17 albino rabbits received a suspension of melanin granules in the subretinal space. Postoperative examination included ophthalmoscopy, color fundus photography, histology using monoclonal antibodies identifying RPE cells (AE1/3), macrophages (RAM 11), B-lymphocytes (CD20) and T-lymphocytes (CD45), and electron microscopy. The follow-up time was 2 weeks, 4 weeks and 6 months.

RESULTS

On fundus photographs, the layer of melanin showed focal attenuation with lighter areas at 6 months. Melanin granules were phagocytosed by RPE cells and macrophages at 2 weeks, as identified by monoclonal antibodies. In areas where an abundance of melanin was present, multilayers of macrophages were seen associated with considerable photoreceptor damage. Pigment-laden cells invaded the neural retina. The cellular infiltration of the retina was focal, and when it involved the outer nuclear layer the photoreceptor damage was severe. Electron microscopy demonstrated the presence of melanosomes intracellularly in Müller glia. The process of phagocytosis and removal of melanin granules from the subretinal space was slow and not completed at 6 months.

CONCLUSION

Our experiments show that implantation of melanin granules in the subretinal space of albino rabbits may induce a considerable phagocytic cellular response featuring the host's RPE, macrophages and glial cells. The migration of pigment-laden cells into the neural retina was associated with focal photoreceptor damage.

Cyclosporine treatment of RPE allografts in the rabbit subretinal space

PURPOSE

To determine the effects of systemic cyclosporine A (CsA) on the survival of retinal pigment epithelial (RPE) allografts in the subretinal space in an animal model using atraumatic transplantation surgery.

METHODS

Following pars plana vitrectomy, an RPE cell suspension from brown rabbits was injected with a glass micropipette into the subretinal space of 39 albino rabbits. For immunosuppression, 22 rabbits were given an injection of CsA, 20 mg daily intramuscularly, 17 rabbits with RPE grafts were controls. The grafts were monitored by biomicroscopy, color fundus photography, and fluorescein angiography. Rabbits were sacrificed at 1, 3 and 6 months, respectively, and the eyes processed for light and electron microscopy including immunohistochemistry.

RESULTS

After three months, the transplanted RPE cells, in both the CsA group and the controls, formed a monolayer in the subretinal space. Although a few macrophages were encountered, there was no massive cellular infiltration and the photoreceptor layer was well preserved. After six months, however, there was a disruption of grafted RPE cells in both groups, characterized by dispersion of melanin pigment in the subretinal space, and invasion of macrophages with focal photoreceptor damage but no infiltration of lymphocytes in the retina or choroid. No significant differences between the CsA treated and the control eyes were discernible.

CONCLUSION

Although the subretinal space has been considered an immunologically privileged site, we found that the survival of RPE allografts was limited. CsA did not prevent RPE allograft destruction in the subretinal space. The transplant seems to be disrupted either by immunological mechanisms that are not inhibited by CsA, or by nonimmunologic events.

Long-term outcome of RPE allografts to the subretinal space of rabbits

PURPOSE

To determine the long-term RPE allograft survival in the subretinal space using suspensions of RPE cells and atraumatic transplantation surgery.

METHODS

Nineteen albino rabbits were transplanted with suspensions of pigmented RPE cells from brown rabbits. Following pars plana vitrectomy, the RPE cell suspension was injected through a small retinotomy using a glass micropipette into the subretinal space under microscopic control. No immunosuppression was used. The eyes were monitored by biomicroscopy, color fundus photography, and fluorescein angiography. Rabbits were sacrificed at 1, 3 and 6 months, respectively, and the eyes processed for light and electron microscopy, using monoclonal antibodies for identifying macrophages.

RESULTS

Transplanted RPE cells were present in the subretinal space in all eyes at 6 months. There was no fluorescein leakage. Generally, the RPE allograft formed a monolayer, but focal fragmentation and disruption with dispersion of melanin pigment occurred. Foci of multilayers of cells in the subretinal space, containing large macrophages, were associated with adjacent photoreceptor damage. There was no infiltration of lymphocytes but macrophages and glial cells were contiguous to the transplant. Cells harboring intracytoplasmatic melanin pigment were observed in the neural retina.

CONCLUSION

Transplantation of RPE cell suspensions to the subretinal space generally forms a monolayer that persists at 6 months. However, in areas of multilayers of RPE cells and macrophages, graft failure occurs in combination with adjacent photoreceptor damage. Graft failure is not associated with the infiltration of lymphocytes, but other mechanisms seem to occur.

Tackling the "dropped nucleus"

PURPOSE

To summarize and analyse the results of our experience in treating patients with a "dropped nucleus".

METHODS

The case records of nineteen patients who underwent surgery for a "dropped nucleus" at the Ophthalmology Departments of Sahlgren's University Hospital, Gothenburg, and Orebro Medical Centre, Orebro, Sweden during 1994 were retrospectively reviewed to determine the mode of treatment used and the results of surgery. The frequency of this complication was also calculated for Sweden as a whole with the help of the National Cataract Register.

RESULTS

The lens was successfully removed in all eyes. No retinal breaks or detachments were present at vitrectomy or follow-up. One eye was lost to panophthalmitis 11 days after the vitrectomy; the remaining 18 eyes showed a favourable outcome.

CONCLUSION

The loss of a crystalline lens to the vitreous during cataract surgery is a severe complication. We recommend that an experienced vitreoretinal surgeon should be consulted at an early stage.

Long-term results of macular pucker surgery

PURPOSE

Macular pucker patients were re-examined 16-90 months after surgery (mean 72 months) to evaluate visual acuity, metamorphopsia, and complications, with particular reference to cataract development. Surgery had been performed on 48 eyes in 46 patients, 31 eyes having a primary, and 17 eyes a secondary macular pucker.

RESULTS

At the 6-month control 65% of the eyes with a primary macular pucker and 35% of the eyes with a secondary macular pucker exhibited an improved visual acuity defined as doubling or more of the visual angle. At the last control 57% of the primary group and 33% of the secondary group had a visual acuity which still exceeded the preoperative value. At the final examination a cataract progression was observed in 22/28 (79%) of the primary group and 8/14 (57%) of the secondary group. In the primary group 11% and in the secondary group 36% of the eyes suffered a retinal detachment. All cases were successfully treated and none were followed by visual deterioration.

CONCLUSION

The improvement in visual quality after macular pucker surgery appears to be long-standing, if not permanent, especially in primary cases. In those eyes in which a decrease in visual acuity is observed, the most frequent cause is cataract development.

The use of perfluorocarbon liquids in vitreoretinal surgery

Two perfluorocarbon liquids (perfluoro-n-octane and perfluorodecaline) were evaluated as technical aids in vitreoretinal surgery in 42 patients. Perfluorocarbon liquids were found to stabilize the retina and simplify removal of repiretinal membranes, which in many cases permitted the subsequent use of an expanding gas instead of silicone oil at the conclusion of the operation. The infusion of a perfluorocarbon liquids allowed the drainage of subretinal fluid through peripheral retinal breaks obviating the need for a retinotomy in most cases. No difference could be observed between the two types of perfluorocarbon liquids, and there were no adverse effects associated with their use. The retina was centrally attached in 32 eyes (76%) at 3-10 months follow-up.

Severe retinopathy of prematurity in infants from the southern regions of Sweden

We studied children born in 1986-1989 with severe retinopathy of prematurity (ROP) defined as stage 3 "plus" or more. Sixteen children from the southern and central areas of Sweden were identified and 15 of these were referred to Orebro Medical Center Hospital for surgical treatment of ROP. The incidence of severe ROP was estimated as 0.8 per 10,000 newborns per year. All children were born before 29 weeks' gestation and weighed less than 1310 g; they also needed ventilatory support for a long time. The overall neonatal morbidity was high. A model for eye examination in premature newborns is suggested.

Healon GV in posterior segment surgery

Healon, a viscoelastic preparation of Sodium hyaluronate, has been reported effective in posterior segment surgery for dissection of epiretinal membranes, i.e. proliferative diabetic retinopathy and macular pucker. A more viscous substance might be more effective for this kind of surgery. Therefore, a new Sodium hyaluronate preparation Healon GV with a ten times greater viscosity at rest than Healon, was tested in an open clinical study. Twenty-four patients of both sexes and not younger than 18 years were enrolled. The follow-up time was three months. The main indications for using Healon GV were: to separate membranes from the retina, to stop bleeding and to reposition a detached retina. 0.2-0.5 ml of Healon GV was injected through a 27 gauge bent cannula and at close of surgery irrigated out of the eye. Postoperatively the patients were monitored concerning intraocular pressure, vitreous clarity, anterior chamber flare and visual acuity. Healon GV was found to make the surgical procedure simpler and safer. No inflammatory reaction and no increase of IOP was observed.

Healon Yellow as a surgical tool in maneuvering intraocular tissues

Tinted sodium hyaluronate (Healon Yellow) was used during posterior segment surgery mainly for the dissection of epiretinal membranes in cases of proliferative diabetic retinopathy and macular pucker. The yellow color facilitated injecting the viscoelastic substance under the membranes and simplified its removal at the end of surgery.

A new technique of treating rhegmatogenous retinal detachment using the Q-switched Nd:YAG laser

In eyes with retinal detachment and a horseshoe break, vitreous traction on the retina has been relieved by severing the flap of the break with the aid of the Q-switched Nd:YAG laser. The retina often flattens in eyes with shallow retinal detachment after this treatment; the breaks then can be sealed off with argon laser. In cases of retinal detachment treated with expanding gas, fewer recurrences were observed when vitreous traction had been relieved by Nd:YAG laser treatment.

Sealing of retinal breaks with metal tacks. Evaluation of a new procedure in retinal re-attachment surgery

Metal retinal tacks were used in 18 patients with complicated retinal detachments, such as giant tears (3 cases), severe proliferative vitreoretinopathy (PVR) (7 eyes) and diabetic traction and rhegmatogenous detachment (8 cases). All eyes had undergone vitreous microsurgery, including excision or segmentation of epiretinal membranes, fluid-air (SF6) or silicone oil exchange. Retinal breaks and the cut edges of retinotomies and retinectomies were successfully sealed by metal tacks. Retinal re-attachment was achieved in 9 cases and partial re-attachment in another 5 eyes (follow-up 3-6 months). Retinal tears in diabetic macular detachment associated with extensive epiretinal fibrovascular membranes were also successfully sealed despite persisting traction. Our first experience indicates that the closing of retinal breaks with metal tacks is a major step forward in retinal re-attachment surgery.