Chorioretinal Toxicity of Perfluorooctane (Ala Octa): Results From 48 Surgical Procedures in Geneva.

PURPOSE: To compare outcomes of patient who underwent surgery using perfluorooctane (PFO; C8F18; Ala Octa) with those who underwent surgery with perfluorodecalin (F-Decalin). DESIGN: Retrospective, consecutive, comparative, interventional case series. METHODS: A total of 48 eyes that underwent vitrectomy with PFO were compared to 29 eyes that underwent vitrectomy with perfluorodecalin. Two experienced surgeons performed vitrectomies at the Geneva University Eye Clinic. Visual acuity before, at 8 and 24 weeks after surgery, was documented, and spectral domain optical coherence tomography (SD-OCT) images were analyzed for abnormalities. RESULTS: Two patients experienced severe retinal toxicity, including 1 with severe vision loss. However, no statistical differences in VA were observed between the PFO and perfluorodecalin patients. Analysis of SD-OCT images showed differences in occurrence of several abnormalities, for example, inner segment-outer segment alterations were found in 60.4% of eyes treated with PFO and in 10.3% of perfluorodecalin-treated eyes; retinal atrophic areas were found in 41.7% of PFO and in none of the perfluorodecalin eyes; inner limiting membrane contraction was found in 58.4% of PFO and in none of perfluorodecalin eyes; inner retina cystic alterations were found in 58.3% of PFO eyes and 17.2% of perfluorodecalin eyes; outer retina cystic alterations were found in 39.6% of PFO eyes and 13.8% of perfluorodecalin eyes; retinal holes were found in 14.6% of PFO eyes and in none of the perfluorodecalin eyes; and outer retinal inclusions were found in 20.8% of PFO eyes and in 3.45% of perfluorodecalin eyes. CONCLUSIONS: Perfluorooctane caused significantly more toxic damage than perfluorodecalin. Special consideration should be given to develop a central European Union (EU) control agency for medical devices and to reevaluate safety procedures currently accepted by the EU and International Organization for Standardization for intraocular surgery.

Cystoid macular oedema and iris-fixated intraocular lens treated with intraocular lens exchange: A case series and review.

This series of case reports describes six eyes from five patients that underwent intraocular lens (IOL) exchange with scleral-fixated IOLs for cystoid macular oedema associated with iris-fixated IOLs between 2005 and 2015. Macular oedema was assessed using ocular coherence tomography (OCT). The six eyes in this series were treated by IOL removal and implantation of a scleral -sutured IOL with four points of fixation in the sulcus. Visual acuity improved in all six eyes. On OCT, macular oedema resolved after 3 months in all eyes. There were no surgical complications from the IOL exchange. One eye had a pupilloplasty and another had a diaphragm IOL to treat a major iris impairment from prior surgeries. The cause of cystoid macular oedema in these cases remains controversial but has been well recognized in eyes with iris-sutured IOLs. The absence of sutures with posterior fixation of an iris claw IOL prevents progressive corneal endothelial cell loss but does not prevent macular oedema, even in vitrectomized eyes. In conclusion, macular oedema resolved and visual acuity improved after implant exchange with a secondary scleral-fixated IOL in these cases. This procedure should be considered as a solution to persistent symptomatic cystoid macular oedema from an iris-fixated implant.

Inflammatory Biomarkers Profile as Microenvironmental Expression in Keratoconus.

Keratoconus is a degenerative disorder with progressive stromal thinning and transformation of the normal corneal architecture towards ectasia that results in decreased vision due to irregular astigmatism and irreversible tissue scarring. The pathogenesis of keratoconus still remains unclear. Hypotheses that this condition has an inflammatory etiopathogenetic component apart from the genetic and environmental factors are beginning to escalate in the research domain. This paper covers the most relevant and recent published papers regarding the biomarkers of inflammation, their signaling pathway, and the potentially new therapeutic options in keratoconus.

Unusual bilateral traumatic maculopathy following whiplash injury.

An unusual extensive bilateral macular oedema (MO) with spontaneous resolution occurred following a car crash accident. Qualitative and quantitative analysis of the macular region using spectral domain optical coherence tomography (SD-OCT) and multifocal electroretinogram (mfERG) was performed daily during the first 7 days, as well as at 3 and 6 months following the accident. SD-OCT examination demonstrated extensive MO accompanied by neurosensory detachment and subretinal fluid. During the 7 days following the accident there was gradual resolution of the oedema accompanied by visual recovery. One year later no anatomical changes were observed, the mfERG showed complete recovery and visual acuity returned to normal level. Although whiplash is a common injury in motor vehicle accidents, whiplash maculopathy (WMP) is rarely reported, most likely due to underdiagnosis. Here we describe the spontaneous resolution of a severe MO after whiplash injury in a car crash accident.

Treatment of diabetic macular edema with sustained-release glucocorticoids: intravitreal triamcinolone acetonide, dexamethasone implant, and fluocinolone acetonide implant.

INTRODUCTION: Diabetic macular edema (DME) can be treated with intravitreal glucocorticoids, particularly triamcinolone acetonide, dexamethasone (DEX), and fluocinolone acetonide (FA). AREAS COVERED: The pathophysiology of DME includes multiple growth factors such as VEGF and also inflammatory mediators. Glucocorticoids act on DME through multiple pathways, and current research into their efficacy, safety, and therapeutic potential when administered intravitreally is discussed. CONCLUSION: The intravitreal route of administration minimizes systemic side effects of glucocorticoids. Furthermore, sustained-release low-dose delivery via the DEX implant or the FA implant will limit frequent intravitreal injection and possibly some cost associated with intravitreal anti-VEGF therapy. In addition, the durable action of these treatments facilitates combination therapy. Patients can receive these implants as foundational therapy, and then receive additional treatment with laser or intravitreal anti-VEGF agents as combination therapy, which may conceivably provide some synergistic benefit. While the FA implant lasts much longer than the DEX implant, potentially decreasing the visit and treatment burden on patients and their families, the FA implant appears to have a greater risk of inducing ocular hypertension and cataract. However, these modalities have not been directly compared in a clinical trial and there is insufficient evidence to draw more elaborate conclusions.

Association of the optic disc structure with the use of antihypertensive medications: the thessaloniki eye study.

PURPOSE: To investigate the association of antihypertensive medications with optic disc structure by blood pressure (BP) level, in nonglaucoma subjects. DESIGN: Cross-sectional, population-based study. METHODS: A subset of Thessaloniki Eye Study participants was included in this study. Subjects were interviewed for medical history and underwent extensive ophthalmic examination, BP measurement, and optic disc imaging with the Heidelberg retinal tomograph. Subjects treated for hypertension were grouped in the following groups: (1) angiotensin-converting enzyme inhibitors and/or angiotensin-receptor blockers; (2) beta blockers and/or calcium-channel blockers; (3) diuretics alone or combined with others; and (4) other combinations. Cup size and cup-to-disc (C/D) ratio in the above groups were compared with the untreated group, using regression models. Analyses were rerun for subjects with systolic BP (SBP)<140 mm Hg, SBP≥140 mm Hg, diastolic BP (DBP)<90 mm Hg, and DBP≥90 mm Hg. RESULTS: Among 232 subjects, 131 were receiving antihypertensive medications. In subjects with DBP<90 mm Hg, all medications groups were associated with larger cup size and higher C/D ratio compared with the untreated group. Results were similar in subjects with SBP<140 mm Hg, with the exception of the beta blockers and/or calcium-channel blockers group. None of the medications groups were associated with the Heidelberg retinal tomograph parameters in those with DBP≥90 mm Hg or SBP≥140 mm Hg. CONCLUSIONS: All classes of antihypertensive medications were associated with larger cup size and higher C/D ratio in subjects with either DBP<90 mm Hg or SBP<140 mm Hg. These results suggest that there is no specific medication-related effect on optic disc structure, and the associations found are mediated through the hypotensive effect of antihypertensive medications.

Femtosecond laser-assisted retinal imaging and ablation: experimental pilot study.

PURPOSE: To investigate retinal imaging and ablation using femtosecond laser pulses. MATERIALS AND METHODS: Two non-amplified near-infrared femtosecond lasers were used to irradiate porcine retinal specimens in vitro. The lasers were used for tissue removal as well as multiphoton laser scanning microscopy. RESULTS: Ablation of the nerve fiber layer was performed at pulse energies of 1.0 nJ to 3.9 nJ. Control laser scanning images were acquired within seconds after irradiation. Specimens were additionally investigated with electron microscopy. CONCLUSIONS: Non-amplified femtosecond lasers may allow precise surgery controlled by fast high-resolution imaging of the target.

Association of blood pressure status with the optic disk structure in non-glaucoma subjects: the Thessaloniki eye study.

PURPOSE: To study the association of blood pressure (BP) status on the optic disk structure as measured with the Heidelberg Retina Tomograph (HRT) in people without glaucoma. DESIGN: Cross-sectional population-based setting study. METHODS: Consecutive participants in the Thessaloniki Eye Study were included in this study. HRT images of the optic disk and BP measurements were taken. Hypertension was defined as a systolic BP (SBP) > or =140 mm Hg, diastolic BP (DBP) >/=90 mm Hg, or both. Subjects were classified in three groups by SBP and DBP. The Kruskal-Wallis test was used to compare the three groups with respect to the HRT parameters. Regression models adjusted for age, gender, height, disk size, intraocular pressure, cardiovascular disease, diabetes, and duration of antihypertensive treatment were used for each HRT parameter to compare values among the different groups. The P value was considered significant at <.05. RESULTS: A total of 232 subjects were included in the analysis. Rim area was significantly different among groups when DBP was considered as the criterion to classify subjects (P = .005). In regression models, cup area, and cup-to-disk (c/d) ratio were increased in subjects with normal DBP that was the result of treatment, as compared with both the high DBP and untreated normal DBP groups. CONCLUSIONS: In patients without glaucoma, the DBP <90 mm Hg that results from antihypertensive treatment is associated with increased cupping and decreased rim area of the optic disk. This information should be considered in research aiming to define the role of the BP status as an independent factor initiating optic disk changes and/or as a contributing factor to glaucoma damage.

The role of optic nerve blood flow in the pathogenesis of glaucoma.

Many theories have surfaced regarding the exact mechanisms behind glaucomatous damage, but the complex nature of the disease and the inaccessibility of the internal structures of the human eye have limited current knowledge. Increased intraocular pressure is the risk factor most often associated with glaucomatous optic neuropathy; ischemic insult to the optic nerve has also been suggested as a possible cause of cellular damage. The aim of this review is to cover the possible role of optic nerve head hemodynamics in the pathogenesis of glaucoma.

Interobserver variability in confocal optic nerve analysis (HRT).

BACKGROUND/AIMS: To study the observer-related variability of optic nerve head (ONH) measurements using confocal laser scanning tomography (HRT I) in a screening setting. METHODS: Six experienced glaucoma specialists independently evaluated 50 ONH topographies from 25 adults using HRT software ver. 2.01 in a masked fashion. ONH topographies were obtained from a cohort study of 882 healthy adults and additionally included one patient with glaucomatous eyes. A glaucoma-screening-like setting was intended. The mean interobserver difference was defined as the mean percentual difference between an observer's analysis and the mean of all six observers for all eyes and all observers. The interobserver range was calculated for each eye as the percentual difference between the lowest and highest measurement, with the highest measurement as denominator. Additionally, Kendall's coefficient of rank concordance was assessed for the main HRT parameters. RESULTS: Mean disc area ranged from 1.83 +/- 0.49 to 2.21 +/- 0.40 mm(2) (mean interobserver difference: 8.3%; interobserver range: 5-50%; rank concordance: 0.86). The lowest mean interobserver differences were found for mean retinal nerve fibre layer thickness (RNFLT; 6.5%), maximum cup depth (2.9%) and cup shape (6.8%). An increased interobserver range was significantly correlated to a low cup to disc area ratio (r=0.64, P<0.0001). CONCLUSIONS: The observer-dependent diagnostic variability of HRT measurements can lead to divergent diagnostic evaluation of the ONH in a screening setting. Any HRT software relying on a reference database is exposed to relevant observer-related variability of the disc area. For screening purposes, HRT measurements should be completed by other diagnostic methods to compensate for possible diagnostic uncertainty.

Comparison of ocular hemodynamics measured by a new retinal blood flowmeter and color Doppler imaging.

BACKGROUND AND OBJECTIVE: To compare measurements of a new retinal blood flow device with central retinal artery blood velocity. MATERIALS AND METHODS: One randomly selected eye from each of 13 subjects was examined. Blood flow was measured by laser blood flowmeter and velocity by color Doppler imaging. The correlation between measurements was analyzed using regression analysis where a P value of less than .05 and coefficient of regression values of greater than .5 were considered significant. RESULTS: The laser blood flowmeter produced vessel diameter measurements of 90.1 +/- 18.7 microm (mean +/- standard deviation), velocity of 19.7 +/- 8.06 mm/sec, and flow measurements of 4.24 +/- 2.41 microL/min. Central retinal artery peak systolic velocity, end diastolic velocity, and mean velocity correlated significantly with laser blood flowmeter velocity (P = .01, r = .66; P < .01, r = .77; and P = .003, r = .76, respectively) and flow (P = .01, r = .71; P = .03, r = .6; and P = .01, r = .69, respectively). CONCLUSIONS: The laser blood flowmeter produces retinal artery flow and velocity measurements that correlate with central retinal artery peak systolic velocity end diastolic velocity, and mean velocity measurements. Further validation of the laser blood flowmeter's accuracy in measuring real flow warranted and likely requires more invasive in vivo studies (in animal models). However, this study supports the ability of the laser blood flowmeter to measure retinal blood flow.

Ultrasound biomicroscopy images: long-term results after deep sclerectomy with collagen implant.

PURPOSE: The aim of this study was to understand the long-term outflow pathway mechanisms after deep sclerectomy - when collagen implant is resorbed - using ultrasound biomicroscopy (UBM). METHODS: Forty-three eyes of 32 patients with medically uncontrolled open-angle glaucoma at least 1 year after deep sclerectomy were studied in an observational, non-randomised, consecutive case series. Postoperatively 15 eyes (35.7%) had goniopuncture with the Nd:YAG laser. Four eyes (9.5%) had postoperative subconjunctival injections of mitomycin C and two eyes (4.7%) had an injection of 5-fluorouracil, because of intraocular pressure (IOP) increase. Complete examination and UBM of the filtering site were performed 1-6 years after surgery. The following parameters were assessed: (1) Presence of a subconjunctival filtering bleb; (2) presence and volume of an intrascleral cavity; (3) presence of a suprachoroidal hypoechoic area. RESULTS: Intraocular pressure decreased significantly from 28.1+/-2.5 mmHg preoperatively to 12.4+/-3.8 (range 7-25) mmHg at the time of UBM (at least 1 year after surgery). Forty eyes showed clinically a diffuse filtering bleb. UBM demonstrated a subconjunctival space in all eyes. In 39 eyes (92.8%) an intrascleral cavity was observed. The mean volume of this cavity was 1.8 (range 0.11-6.53) mm(3). In 19 eyes (45.2%) we observed a hypoechoic area in the suprachoroidal space. CONCLUSION: UBM examination demonstrated several aqueous humour drainage pathways. A low-reflective diffuse subconjunctival space meant persistent filtration in all eyes. More than 1 year after surgery 92.8% of eyes had a remaining intrascleral cavity. In almost half of the patients an additional suprachoroidal outflow was observed, significantly correlated with a lower IOP.