Intra‐ocular diathermy forceps

Purpose

The purpose of this study was to develop intra‐ocular diathermy forceps and test them on perfused porcine cadaver eyes.

Methods

We designed two types of 23‐gauge intra‐ocular bipolar diathermy forceps by modifying commercially available membrane peeling forceps. In the first type, the emitting electrode is connected to one‐half of the core and the return electrode to the other half, with one jaw of the forceps attached to each half. In the second type, the emitting electrode is attached to the core and both jaws of the forceps, and the return electrode to the surrounding tube. We compared the new diathermy forceps to conventional intra‐ocular diathermy, on perfused porcine cadaver eyes. First‐order retinal artery and vein closure was confirmed both by a perfusion study and by histology of the treated vessels.

Results

Type 1 diathermy forceps closed retinal arteries and veins more successfully (five of five and five of five successful treatments, respectively) than Type 2 diathermy forceps (five of five and four of five, respectively) and conventional diathermy (three of five and four of five, respectively). Less energy was used with Type 1 compared to Type 2 and conventional for artery closure (1.5 ± 0.0 versus 4.6 ± 3.3 versus 2.1 ± 0.8 joules, respectively) and vein closure (1.5 ± 0.0 versus 5.4 ± 4.6 versus 2.4 ± 0.8 joules, respectively). Histology of the treated vessels confirmed the perfusion study results.

Conclusion

We designed two types of a new multifunctional intra‐ocular instrument with the ability to peel membranes and to grasp, compress and coagulate retinal blood vessels. Both types pose operational advantages compared to current conventional intra‐ocular diathermy.     

Retinal artery occlusion following intravitreal anti‐VEGF therapy

Purpose: Anti‐vascular endothelial growth factor (anti‐VEGF) therapy effectively inhibits angiogenesis and is now enjoying widespread use in the treatment of age‐related macular degeneration (AMD). It may also have a role in the treatment of macular oedema secondary to other conditions. VEGF is a signalling molecule that has a variety of roles, including vasoregulation and effects on the coagulation homeostasis. Anti‐VEGF therapy may therefore have adverse effects on ocular blood flow. Methods: Two cases of retinal artery occlusion after intravitreal injection of anti‐VEGF are presented. Both patients were given the treatment to reduce macular oedema secondary to central retinal vein occlusion. Possible mechanisms are discussed. Results: Patient 1 developed a central retinal artery occlusion within 1 month of an intravitreal injection of ranibizumab (Lucentis^®). The macular oedema was totally resolved at 1 month; final visual acuity (VA) was light perception. Patient 2 developed a branch retinal artery occlusion in the macula 2 days after an intravitreal injection of bevacizumab (Avastin^®). The macular oedema was almost resolved within 1 week and did not recur; final VA was 0.6. Conclusions: Anti‐VEGF therapy may have a role in the treatment of macular oedema caused by central retinal vein occlusions. However, our report indicates that the therapeutic principle may be associated with an increased risk of retinal arterial occlusions.     

Retinal capillary angioma managed with trans‐pupillary thermotherapy

Retinal capillary angioma is a tumour‐like nodule of the retina and was first described in 1904 by von Hippel. This disease is characterised among the congenital syndromes known as the phakomatoses. It is the only known phakomatosis that does not exhibit skin lesions. A patient with retinal capillary angioma with leakage and haemorrhage is described and the differential diagnosis discussed. In addition, this patient was treated with transpupillary thermotherapy and the available therapies are summarised.     

Long‐term results of the effect of intravitreal ranibizumab on the retinal arteriolar diameter in patients with neovascular age‐related macular degeneration

Purpose: To study the effect of intravitreal (IVT) ranibizumab on the retinal arteriolar diameter in patients with neovascular age‐related macular degeneration (AMD). Methods: Ten eyes of 10 patients with previously untreated neovascular AMD were included. All eyes had three monthly IVT injections of ranibizumab and then were retreated as needed, based on visual acuity and optical coherence tomography (OCT) criteria. The diameter of the retinal arterioles was measured in vivo with a retinal vessel analyser (RVA) before the first IVT injection, 7 and 30 days after the first, the second and the third injection, and at month 12 of follow‐up. Results: A significant vasoconstriction of the retinal arterioles was observed following each one of the first three IVT injections of ranibizumab. Thirty days following the first, second and third injection, there was a mean decrease of 8.4 ± 3.2%, 11.9 ± 4.5% and 18.5 ± 7.2%, respectively, of the retinal arteriolar diameter compared with baseline (p < 0.01). At month 12, the vasoconstriction was still present with a mean decrease of 19.1 ± 8.3% of the retinal arteriolar diameter compared with baseline (p < 0.01). Median number of ranibizumab injections was 4 (range 3–10). There was no correlation between the number of injections and percentage diameter decrease at month 12 (r = ?0.54, p > 0.1). There was no significant change in mean arterial pressure (MAP) during the period of follow‐up (p > 0.05). Conclusions: These results suggest that IVT ranibizumab induces sustained retinal arteriolar vasoconstriction in eyes with neovascular AMD.     

Bilateral macular sub‐retinal fluid and retinal pigment epithelial detachment associated with type 2 membrano‐proliferative glomerulonephritis

Choroidal neovascularisation (CNV) and idiopathic central serous chorioretinopathy (ICSC) are recognised ocular complications related to type 2 membrano‐proliferative glomerulonephritis. We report a 38‐year‐old white male who presented with a 10‐day history of blurring of vision, micropsia and metamorphopsia. He had been diagnosed recently to have type 2 membrano‐proliferative glomerulonephritis. On examination, there was bilateral retinal pigment epithelial (RPE) detachment with overlying sub‐retinal fluid without any drusen. Fundus fluorescein angiography (FFA) and optical coherence tomography (OCT) confirmed the diagnosis of atypical ICSC. Three months later, sub‐retinal fluid and RPE detachment resolved and VA had recovered to 6/6. The case highlights the importance of ophthalmological assessment in these patients to recognise sight‐threatening complications.     

Interpretation of RNFLT values in multiple sclerosis‐associated acute optic neuritis using high‐resolution SD‐OCT device

Purpose: Optical coherence tomography (OCT) has emerged as the technique of choice in measuring the retinal nerve fibre layer (RNFL) quantitatively. It is suggested that RNFL reduction may correlate with lesion burden and diffuse axonal degeneration in the whole CNS of patients with multiple sclerosis (MS). However, RNFL changes because of optic neuritis (ON) must be taken into account. Methods: Twenty‐three patients with acute ON (46 eyes) associated with clinical definite MS (23 ON eyes, 23 fellow eyes) and 23 sex‐ and age‐matched healthy controls were studied. Retinal nerve fibre layer thickness (RNFLT) was measured at baseline, using a high‐resolution spectral domain OCT (SD‐OCT) applying circular, peripapillary OCT scans with a novel eye‐tracking mechanism. Results: The internal OCT software was able to identify RNFL atrophy in three out of five of the acute ON eyes and one out of four of the fellow eyes with previous ON episodes. Retinal nerve fibre layer thickness of two ON (8.7%) and five fellow eyes (21.7%) was overestimated, thus located within the 95% and 5% confidence interval of the company standard values (not marked pathologic). In contrast, our comparison with age‐ and sex‐matched controls revealed RNFL atrophy suggestive of prior, clinically silent RNFL loss in ON and fellow eyes (30.4%). Conclusion: Retinal nerve fibre layer thickness measurements at a single time‐point seem to have a limited role in detecting prior clinically silent optic nerve injury. Our data suggest that affected eyes should be compared with the fellow eyes and a sufficient number of age‐ and sex‐matched controls to allow the detection of even subtle RNFL changes at baseline. The role of OCT for disease monitoring of MS must be evaluated in detail, as ON is often the initial symptom of MS.     

Retinal thickness in myopic and non‐myopic eyes*

Purpose: To investigate the retinal thickness profile in myopic and non‐myopic eyes. Methods: The retinal thickness profile of 30 myopic eyes [spherical equivalent error (SER) between ?6.00 and ?13.63 D] and 31 non‐myopic eyes (SER between +2.75 and ?0.50 D) were measured using the Stratus OCT (Carl Zeiss Meditec, Dublin, CA, USA). Two scan types were used: the Macular Thickness Map and the Customized Line Scan for a central 80° horizontal retinal thickness profile. Results: At foveal center and fovea, myopic eyes had a thicker retina than the non‐myopic group (p = 0.002 and 0.044, respectively). At other zones of the macula, the retina was significantly thinner in myopic eyes compared to non‐myopic eyes (p < 0.01, unpaired t‐test). From 40° nasal to 40° temporal retina, a general reduction of retinal thickness was observed across the myopic retina compared to the non‐myopic retina except at 20° nasal to fixation. Conclusions: There was general reduction in retinal thickness within the horizontal central 80° in myopic eyes compared with non‐myopic eyes.     

Functional and anatomical results after a single intravitreal Ozurdex injection in retinal vein occlusion: a 6‐month follow‐up – The SOLO study

Purpose:  To evaluate the efficacy of intravitreal dexamethasone implants in eyes with cystoid macular oedema (CME) secondary to branch retinal vein occlusion (BRVO) or central retinal vein occlusion (CRVO) in the clinical everyday practice, examine the effects of early retreatment and compare the results with the GENEVA study. Methods:  The charts of 102 patients (102 eyes) with CME secondary to BRVO (n = 54) or CRVO (n = 48) treated with Ozurdex at 8 centres were retrospectively reviewed. The patients were examined monthly over a 24‐week period. Slit‐lamp biomicroscopy, measurement of best‐corrected visual acuity (BCVA) and measurement of the central retinal thickness (CRT) with spectral‐domain optical coherence tomography (SD‐OCT) were performed at baseline and at every follow‐up examination. With progression of the disease (loss of one line or increased central retinal thickness (CRT) of 150 μm), a reinjection of Ozurdex or anti‐VEGF was offered. Additional supplementing sectorial or panretinal laser photocoagulation was considered based on the individual status of the retina. Results:  In the BRVO group, the median BCVA was 0.6 logMAR (Snellen equivalent of 0.25) at baseline and improved to 0.4 logMAR (Snellen equivalent of 0.40) after 4 weeks, 0.3 logMAR (Snellen equivalent of 0.50) after 8 weeks, 0.4 logMAR (Snellen equivalent of 0.40) after 12 weeks, 0.5 logMAR (Snellen equivalent of 0.32) after 16 weeks, 0.4 logMAR (Snellen equivalent of 0.40) after 20 weeks and 0.45 logMAR (Snellen equivalent of 0.35) after 24 weeks. The mean CRT was 559 ± (SD) 209 μm at baseline and it decreased to 335 ± 148 μm after 4 weeks, 316 ± 137 μm after 8 weeks, 369 ± 126 μm after 12 weeks, 407 ± 161 μm after 16 weeks, 399 ± 191 μm after 20 weeks and 419 ± 196 μm after 24 weeks. In the CRVO group, the median BCVA was 0.7 logMAR (Snellen equivalent of 0.20) at baseline and improved to 0.4 logMAR (Snellen equivalent of 0.40) after 4 weeks, 0.4 logMAR (Snellen equivalent of 0.40) after 8 weeks, 0.6 logMAR (Snellen equivalent of 0.25) after 12 weeks, 0.6 logMAR (Snellen equivalent of 0.25) after 16 weeks, 0.5 logMAR (Snellen equivalent of 0.32) after 20 weeks and 0.52 logMAR (Snellen equivalent of 0.30) after 24 weeks. The mean CRT at baseline was 740 ± 351 μm and it decreased to 419 ± 315 μm after 4 weeks, 352 ± 261 μm after 8 weeks, 455 ± 251 μm after 12 weeks, 497 ± 280 μm after 16 weeks, 468 ± 301 μm after 20 weeks and 395 ± 234 μm after 24 weeks. The BCVA improvement was statistically significantly better (p < 0.05) compared with baseline in both groups at every follow‐up visit. The mean CRT maintained significantly better when compared with baseline in both groups at all follow‐up visits. Early reinjection was indicated in BRVO in 40.7% after 17.5 ± 4.2 weeks and in CRVO in 50% after 17.68 ± 4.2. Six eyes (11%) with BRVO received a sectorial laser photocoagulation at a mean interval of 22 ± 5.0 weeks. Seven eyes (15%) with CRVO received a panretinal laser photocoagulation after a mean interval of 18 ± 7.0 weeks. The BCVA improvement and the mean CRT reduction were statistically significant (p < 0.05) compared with baseline in both groups at every follow‐up visit. Conclusions:  Dexamethasone intravitreal implant resulted in a significant improvement of the BCVA and reduction of CME in patients with BRVO or CRVO. Early retreatment after 16 weeks instead of 24 weeks, like in the GENEVA study, was indicated in 50% to stabilize the improved functional and anatomical results.     

Phenotypic findings in C1QTNF5 retinopathy (late‐onset retinal degeneration)

Purpose: To describe the ocular and electrophysiological phenotype of four patients with late‐onset retinal degeneration (LORD). Methods: Clinical examination, fundus and anterior segment photography, fundus autofluorescence imaging and spectral domain optical coherence tomography (SD‐OCT) were performed. Three patients underwent pattern and full‐field electroretinography (ERG). Patient DNA was screened for the c.686C>G, p.Ser163Arg mutation in C1QTNF5. Results: All affected individuals had a family history suggestive of autosomal dominant inheritance with full penetrance. Molecular analysis identified a heterozygous c.686C>G, p.Ser163Arg mutation in C1QTNF5 in DNA from all four affected probands. All four patients presented in their 50s with nyctalopia and developed central visual loss in their 60s. Peripupillary iris atrophy and long anterior zonular insertions were present in three of four patients. Dilated fundus examination revealed scalloped areas of retinal pigment epithelium (RPE) atrophy in the mid‐periphery and widespread atrophy in the posterior pole. Full‐field ERGs were consistent with rod‐cone dystrophy with pattern ERG evidence of severe macular involvement. SD‐OCT revealed widespread loss of the photoreceptors with absence of the inner/outer segment junction line and concurrent thinning of the outer nuclear layer. Diffuse choroidal thinning, mainly affecting the inner choroid with loss of the choriocapillaris, was observed. Conclusion: C1QTNF5 retinopathy is an autosomal dominant LORD resulting in a complex ocular phenotype involving the RPE and ciliary epithelium. SD‐OCT findings revealed widespread photoreceptor loss and diffuse choroidal thinning.     

Optos‐guided pattern scan laser (Pascal)‐targeted retinal photocoagulation in proliferative diabetic retinopathy

Purpose: To investigate the clinical effects and safety of targeted pattern scan laser (Pascal) retinal photocoagulation (TRP) in proliferative diabetic retinopathy (PDR). Methods: Prospective and non‐randomized study of 28 eyes with treatment‐naive proliferative diabetic retinopathy (PDR). Single‐session 20‐ms‐Pascal TRP strategy applied 1500 burns to zones of retinal capillary non‐perfusion and intermediate retinal ischaemia guided by wide‐field fluorescein angiography (Optos). Main outcome measures at 12 and 24 weeks included; PDR grade (assessed by two masked retina specialists); central retinal thickness (CRT); mean deviation (MD) using 24‐2 Swedish interactive threshold algorithm (SITA)‐standard visual fields (VF); and ETDRS visual acuity (VA). Results: Following primary TRP, there was PDR regression in 76% of patients at 12 weeks (κ = 0.70; p < 0.001). No laser re‐treatment was required at 4 weeks, and 10 eyes underwent repeat TRP at 12 weeks. Wide‐field Optos angiography at 24 weeks showed complete disease regression in 37% and partial regression in 33%. Additional panretinal laser photocoagulation (PRP) was planned for active PDR in 30%. There were significant reductions in CRT over time (10.4 μm at 12‐weeks, p = 0.007; 12.1 μm at 24‐weeks, p = 0.0003). The MD on VFs improved after 12 weeks (+1.25 dB; p = 0.015) and 24 weeks (+1.26 dB, p = 0.01). The VA increased by +3 letters at 24 weeks (95% CI, 1.74–5.01; p < 0.0001). Conclusions: This pilot study reports that Optos‐guided Pascal 20‐ms TRP using 1500 burns for treatment‐naive PDR is a promising procedure with favourable safety profile.