Collagen Cross- Linking for Paediatric Keratoconus

Background:

Since the late 1990s corneal crosslinking (CXL) has been proposed as a new treatment option which can stop progression of keratoconus with promising results in adults.

Objective:

Keratoconus presents a higher rate and faster progression in paediatric patients and for this reason prompt and effective treatment is essential. Due to its success in adult keratoconus patients, CXL has been recently applied to children in order to stop or slow progression of keratoconus in paediatric patients.

Conclusions:

This article will present an update of the literature on the topic of CXL in this age group.

Investigation of associations of ARMS2, CD14, and TLR4 gene polymorphisms with wet age-related macular degeneration in a Greek population

Background

Age-related macular degeneration (AMD) is a multifactorial degenerative ocular disease that leads to loss of central vision. Functional gene polymorphisms have already been associated with the disease (for example, ARMS2 A69S, rs10490924).

Aim

The goal of our study was to verify the correlation of the aforementioned ARMS2 variation with the disease, to examine, for the first time, the role of the CD14 C260T variation (rs2569190), and to investigate the association of two TLR4 polymorphisms (Asp299Gly or rs4986790 and Thr399Ile or rs4986791) in a Greek population with the wet form of AMD.

Patients and methods

Genomic DNAs were isolated from blood samples of 103 healthy controls and 120 Greek patients with wet AMD who were age- and sex-matched, and all of whom were clinically evaluated. For the genotyping of all selected polymorphisms, polymerase chain reaction–restriction fragment length polymorphism analysis was performed.

Results and conclusions

This study confirmed the association between the ARMS2 variation and AMD, detecting the T risk allele in a significantly higher frequency in the patient group, compared with the control subjects (45% vs 29.13%, P<0.001, odds ratio [OR] 1.99, confidence interval 1.34–2.95). For the CD14 polymorphism, no statistically significant correlation was observed. As for the TLR4 polymorphisms, the percentage of heterozygotes increased from 2.9% to 11.7% in the patient population for Asp299Gly and from 1.9% to 10% for the Thr399Ile polymorphism (ORs 4.40 [P=0.01] and 5.61 [P=0.0088], respectively). Although our ARMS2 and CD14 results provided definite conclusions, the role of innate immunity TLR4 gene awaits further investigation in larger AMD populations with more clinical data collected on past microbial infections.

Homosexuality according to ancient Greek physicians

Homosexuality and pedophilia in ancient Greece greatly concerned many researchers who were mainly interested in highlighting the social aspect of this phenomenon in ancient Greek society. An important source on the subject was the paintings of a man and his lover in attic black and red figured pottery, up to the end of the 5th century BC. Another main source was the information that derived from the texts of ancient Greek literature, especially poetry. Homosexuality was not only referring to relationships between males, but it was also manifested in lesbian love. It is believed that in the Homeric world homosexuality was not favored. In Greek society of the archaic period, the restriction of women at home, the satisfaction of sexual needs with courtesans, the marriage for the purpose of maintaining and managing the property, put women aside, marginalizing them in terms of social life, impeding the cultivation of emotional relationships between sexes. At the same time, in the society of those times, the aristocratic ideal, the constant communication of men during military training and the war, the male nudity in sports and the promotion of beauty and bravery in athletic contests, as well as the gatherings and the entertainment of men at the symposia, created a suitable substrate in which male homosexuality could develop. In this context, pedophile relationships were developed mainly during the archaic period, as recorded on vase paintings, where a mature man developed a special relationship with a teenager of the same social class. The mature man had the role of mentor for the juvenile, he would look after him and cover his living expenses and education cost. In this relationship, exhibiting predominantly the social dimension of an initiation process and introduction to adult life, the erotic homosexual intercourse could find a place to flourish. The above-mentioned relationship could not last forever, given that this would later transform into an emotional connection of friendship and trust. Besides, the constant homosexual relationships and male prostitution were considered to be reprehensible behaviors. Regarding the lesbian love, the main example was Sappho and her poems that praised love between women. Nevertheless, the relationship with the girls in the poems is considered to be similar to that Socrates had with his students, an intense personal relationship which would not involve sexual love and could probably be a platonic love. Ancient Greek physicians used their methodological tools in order to interpret homosexuality as a mental disease, but ancient medical dogmas such as the theory of humors, stereopathology and their variations could not offer an explanation for homosexuality.

Professor Sergei Semjonovic Golovin (1866-1931): A Pioneer of Ocular Surgery

Professor Sergei Semjonovic Golovin (1866-1931) is considered as one of the founders of ophthalmology in Russia. He received a worldwide reputation thanks to his achievements in ocular surgery and pathology. He introduced new surgical techniques such as Golovin's operation (Exenteratio orbitosinualis), Golovin's osteoplastic frontal sinus operation, ligation of orbital veins, and opticociliary neurectomy. He also introduced his "cytotoxic theory" to interpret sympathetic ophthalmia. He was a reputable professor of ophthalmology.

Anti-platelet effects of anti-glaucomatous eye drops: an in vitro study on human platelets

PURPOSE

Altered platelet aggregability has been implicated in the pathogenesis of glaucoma. This study aims to investigate the anti-platelet potential of intraocular pressure lowering drops, with the possibility of establishing it as an additional mechanism of anti-glaucomatous action.

MATERIALS AND METHODS

The anti-aggregating effects of a series of anti-glaucomatous eye drops were determined on human platelets in the platelet aggregation model, using four known aggregating factors (platelet activating factor [PAF], adenosine diphosphate [ADP], thrombin receptor-activating peptide [TRAP], and arachidonic acid [AA]).

RESULTS

Almost all of the tested samples inhibited platelet aggregation induced by PAF, ADP, TRAP, and AA, except for Alphagan, which did not demonstrate inhibition of ADP- and TRAP-induced aggregation at a wide range of concentrations. Trusopt, Betoptic, and Azarga eye drops were the most potent inhibitors of all four aggregating factors, while Alphagan was the least potent (P<0.05).

CONCLUSION

This study shows that anti-glaucomatous eye drops possess anti-platelet effects, and this was shown for the first time by experimenting on human platelets.

Receptor of Advanced Glycation End Products Gene Polymorphism and Primary Open-Angle Glaucoma

PURPOSE

The purpose of this study was to investigate the potential association between primary open-angle glaucoma and receptor of advanced glycation end products (AGER) polymorphisms in a Greek population.

METHODS

This is a case-control study of 106 patients with primary open-angle glaucoma and 120 healthy control subjects of Greek origin surveyed for AGER polymorphisms (rs1051993 and rs2070600) and a potential correlation to primary open-angle glaucoma.

RESULTS

AGER polymorphisms showed no statistically significant difference between patients with primary open-angle glaucoma and healthy controls.

CONCLUSIONS

Our study did not find any significant association between AGER polymorphism and primary open-angle glaucoma. Since we cannot reject the possibility that oxidative stress is a crucial factor for the development of primary open-angle glaucoma, further studies may be needed to confirm the importance of the AGER gene in the glaucoma pathogenesis.

Dreams in ancient Greek Medicine

Dreams preoccupied the Greek and Roman world in antiquity, therefore they had a prominent role in social, philosophical, religious, historical and political life of those times. They were considered as omens and prophetic signs of future events in private and public life, and that was particularly accentuated when elements of actions which took place in the plot of dreams were associated directly or indirectly with real events. This is why it was important to use them in divination, and helped the growth of superstition and folklore believes. Medicine as a science and an anthropocentric art, could not ignore the importance of dreams, having in mind their popularity in antiquity. In ancient Greek medicine dreams can be divided into two basic categories. In the first one -which is related to religious medicine-dreams experienced by religionists are classified, when resorted to great religious sanctuaries such as those of Asclepius (Asclepieia) and Amphiaraos (Amfiaraeia). These dreams were the essential element for healing in this form of religious medicine, because after pilgrims underwent purifications they went to sleep in a special dwelling of the sanctuaries called "enkoimeterion" (Greek: the place to sleep) so that the healing god would come to their dreams either to cure them or to suggest treatment. In ancient Greek literature there are many reports of these experiences, but if there may be phenomena of self-suggestion, or they could be characterized as propaganda messages from the priesthood of each sanctuary for advertising purposes. The other category concerns the references about dreams found in ancient Greek medical literature, where one can find the attempts of ancient Greek physicians to interpret these dreams in a rational way as sings either of a corporal disease or of psychological distress. This second category will be the object of our study. Despite the different ways followed by each ancient Greek physician in order to explain dreams, their common intention was to give a rational answer for the creation and content of dreams setting aside any supernatural beliefs. In addition they tried to explain in a scientific way the correlation that could have emerged between the story that took place in dreams and the events that happened in everyday life. Nevertheless, ancient Greek physicians focused especially on nightmares, which were associated with physical problems. For those physicians these nightmares included information about the corporal disease of the patient, which had a reflection in the dream, and they could help them to diagnose the problem in order to restore balance of the body.

The Effect of Vitamin E on Oxidative Stress Indicated by Serum Malondialdehyde in Insulin-dependent Type 2 Diabetes Mellitus Patients with Retinopathy

Background:

Several studies have focused on oxidative stress on diabetes mellitus (DM). Our purpose was to investigate the impact of oxidative stress on progression of diabetic retinopathy (DR) in insulin-dependent type 2 DM patients, measuring serum malondialdehyde (MDA), as well as to examine the effect of vitamin E on DR progression in the above-mentioned patients.

Methods:

Participants in the study were 282 insulin-dependent type 2 DM patients with DR. All participants underwent a thorough ophthalmological examination, so as to grade DR, along with serum MDA measurement. All participants received 300mg vitamin E daily for 3 months and were examined again. Serum MDA pre- and post-intake of Vitamin E was the main outcome.

Results:

Serum MDA was positively associated with DR stage, while there was a statistically significant difference pre- and post-intake of vitamin E in all DR stages. In a subgroup analysis of patients with proliferative DR, there was a significant difference at baseline between patients who have received prior laser photocoagulation and the treatment naïve patients, while after intake of vitamin E, no statistically significant difference was noticed.

Conclusion:

Oxidative stress has been found to play significant role in the pathogenesis and progression of DR, while vitamin E seems to reduce MDA levels and subsequent oxidative stress, suggesting that it might have protective role in DR progression.

Electrophysiological assessment for early detection of retinal dysfunction in β-thalassemia major patients

PURPOSE

The purpose of this study was to assess the role of various diagnostic tests in early detection of retinal changes in β-thalassemia major patients.

METHODS

Thirty-eight visually asymptomatic β-thalassemia major patients receiving regular blood transfusions and iron-chelation therapy with deferoxamine (group A, n = 13), deferasirox (group B, n = 11) or deferoxamine with deferiprone (group C, n = 14) and fourteen age- and sex- matched healthy individuals were included in the study. All participants underwent ophthalmoscopy, full-field electroretinography (ERG), visual evoked potentials (VEP), multifocal electroretinography (mfERG), fundus autofluorescence (FAF) imaging and optical coherence tomography (OCT) scans.

RESULTS

Retinal pigment epithelium changes were present in two cases. Scotopic ERG demonstrated decreased a-wave amplitude in groups A, B and C (p = 0.03, p = 0.002 and p = 0.002, respectively) and decreased b-wave amplitude in groups B and C (p = 0.002 and p = 0.01, respectively) compared to controls. Photopic ERG showed delayed b-wave latency in groups A and C (p = 0.03 and p = 0.03, respectively) ERG maximal combined response and VEP response did not differ between groups. MfERG showed reduced retinal response density in ring 1 in groups A, B, C (p < 0.001, p < 0.001, p = 0.001, respectively) and ring 2 in group B (p = 0.02) and delayed latency in ring 5 in groups A and B (p = 0.04 and p = 0.04, respectively). Abnormal FAF images appeared in three cases and OCT abnormalities in one case, whereas no changes were observed in controls (p = 0.55 and p = 1.00, respectively).

CONCLUSIONS

Full-field ERG and mfERG are more sensitive tools for detecting early retinal changes in β-thalassemia patients compared with ophthalmoscopy, VEP, FAF imaging and OCT scans.

The Role of mf-ERG in the Diagnosis and Treatment of Age-Related Macular Degeneration: Electrophysiological Features of AMD

INTRODUCTION

Age-related macular cegeneration (AMD) is the leading cause of visual dysfunction worldwide, affecting 9-25% of individuals between 65 and 75 years old.

METHODS

We have reviewed the published articles investigating the role of multifocal electroretinogram (mf-ERG) in the diagnosis and treatment of AMD.

RESULTS

Visual evoked potentials have revealed decreased amplitudes and higher latencies in patients with AMD, while the degeneration of photoreceptors and abnormalities of retinal pigment epithelium can be identified by electro-oculogram recordings. Moreover, ERG can detect the functional abnormalities observed in AMD and evaluate each therapeutic approach. The record of local electrophysiological responses coming from different retinal areas can be accurately performed by mfERG.

CONCLUSION

The accuracy of mfERG in detecting the degeneration of photoreceptors, as well the disturbances of macular function, could be useful both in the early diagnosis of AMD and the assessment of treatment efficacy.

Subconjunctival orbital fat prolapse and thyroid associated orbitopathy: a clinical association

Background

Thyroid associated orbitopathy (TAO) comprises a spectrum of well-recognized clinical signs including exophthalmos, eyelid retraction, soft tissue swelling, ocular misalignment, keratopathy as well as a number of less common manifestations. Subconjunctival fat prolapse is a rare clinical condition occurring typically spontaneously in elderly patients with a mean age of 65–72 years. We describe subconjunctival prolapse of orbital fat as an uncommon clinical association of TAO.

Materials and methods

Observational study of six patients presenting with a subconjunctival protrusion under the lateral canthus in a series of 198 consecutive cases with TAO examined at a tertiary care referral center.

Results

A superotemporally located yellowish, very soft, freely mobile subconjunctival protrusion developed unilaterally in two and bilaterally in four patients with TAO (incidence 3.03%). It was one of the presenting manifestations of TAO in four of ten eyes studied and incited the diagnostic work-up for TAO in two of six patients in this series. Magnetic resonance imaging of the orbit indicated fat density in continuity with intraorbital fat in the area of protrusion. A male to female preponderance of 4:2 and an advanced mean age at onset of TAO is noteworthy for these six patients compared to the pool of 192 patients (64.8 versus 51.8 years, respectively, P=0.003) not bearing this sign.

Conclusion

Subconjunctival orbital fat prolapse, a clinically impressive age-related ocular lesion, may occasionally predominate amid other clinical manifestations of TAO. It is a nonspecific sign developing most commonly among patients with a relatively advanced age at presentation. Awareness of this association may alert to the diagnosis of thyroid orbitopathy and reassure the patient and physician as to the benign character of the lesion.

Ranibizumab versus aflibercept for macular edema due to central retinal vein occlusion: 18-month results in real-life data

PURPOSE

The objective of this study was to compare the anatomical and functional outcomes of ranibizumab versus aflibercept for the treatment of macular edema due to central retinal vein occlusion (CRVO) in routine clinical practice.

METHODS

Participants in this observational study included 62 treatment-naïve patients with CRVO who received intravitreal injections of either ranibizumab or aflibercept. The demographic data, best-corrected visual acuity (BCVA) and spectral-domain optical coherence tomography (SD-OCT) characteristics were evaluated at baseline and at months 1, 2, 3, 6, 12 and 18 post-treatment.

RESULTS

At month 18, the mean BCVA of ranibizumab-treated eyes increased 7.9 letters, compared to 7.4 letters for eyes receiving aflibercept, with a similar number of injections. There was no statistically significant difference between the two groups in letters or in central subfield thickness at month 18. At the end of the follow-up, 50% of patients in the ranibizumab group and 42.9% in the aflibercept group showed complete resolution of macular edema.

CONCLUSIONS

Ranibizumab and aflibercept demonstrated similar anatomical and functional outcomes over 18-month follow-up in patients with macular edema due to CRVO, with a similar number of injections.

Dark Adaptation in Patients with Primary Open-Angle Glaucoma, Pseudoexfoliation Glaucoma and Childhood Glaucoma

Purpose To investigate the state of dark adaptation and macular blood flow in different forms of glaucoma. Methods Eighteen eyes of 18 patients with primary open-angle glaucoma, 14 eyes of 14 patients with pseudoexfoliation glaucoma, and 10 eyes of 10 patients with childhood glaucoma (CG) were examined by means of dark adaptometry, scanning-laser retinal flowmetry, and retinal tomography. Results All glaucomatous eyes had comparable optic disc excavation (one-way ANOVA, p = 0.138). Eyes with CG had significantly lower best-corrected visual acuity than the other groups (Tukey, all p < 0.0001). Macular perfusion was comparable in all three groups (one - way ANOVA, p = 0.08). The delay in rod-cone break time in the CG group was significantly higher than in the other groups (Tukey, all p < 0.0001). The scotopic sensitivity threshold in the CG group was significantly greater than in the other groups (Tukey, all p < 0.01). Conclusion This underlying dysfunction of dark adaptation may contribute, at least to some extent, to the decreased visual perception observed in patients with CG.

The beginning of using X-rays and the evolution of equipment for the treatment of ocular cancer

Until the early 20^thcentury enucleation of the eyeball or its partial excision were the basic treatments for ocular cancer. The discovery of X-rays by Wilhelm Conrad Röntgen (1845-1923) offered new possibilities to the treatment of ocular cancer either as mono or as adjuvant therapy. Nowdays this treatment is more sophisticated.

Comparison of Goldmann applanation tonometry and Pascal dynamic contour tonometry in relation to central corneal thickness and corneal curvature

Purpose

The aim of the study was to assess the influence of central corneal thickness (CCT) and corneal curvature in tonometry measurements taken by Goldmann applanation tonometry (GAT) and Pascal dynamic contour tonometry (DCT).

Methods

This was a prospective study of 185 eyes from 97 subjects, attending outpatient ophthalmology appointments, who underwent intraocular pressure measurements by GAT and Pascal DCT. CCT and corneal curvature were obtained using ultrasound pachymetry and Orbscan topography, respectively. All measurements were carried out among males and females during the period 2009–2012. Apart from the usual descriptive and exploratory data analysis, one-way analysis of variance and agreement analysis were performed, linear as well as intraclass correlation coefficients were estimated, and multiple scatter and Bland–Altman plots were produced.

Results

Mean IOP measurements obtained were 17.21±4.10 mmHg by DCT and 13.23±4.07 mmHg by GAT. Mean difference between the GAT and DCT measurements was 3.88±2.8 mmHg. Mean CCT and corneal curvature were 522.78±52 μm and 43.83±2.9823 D, respectively.

Conclusion

Intraocular pressure measured by GAT was consistently lower when compared with DCT, and this difference was greatest with thinner CCT. Flat corneas seem to influence GAT measurements compared to DCT.

Impact of prostaglandin glaucoma drops on platelet-activating factor action: an in vitro study

AIM

The aim of this study was to investigate the effect of different prostaglandin analogs on platelet-activating factor (PAF) levels.

METHODS

Three prostaglandin analogs were selected: bimatoprost 0.3 mg/mL, latanoprost 50 μg/mL, and tafluprost 15 μg/mL. Each drug sample was tested for its ability to cause platelet aggregation, which was measured as PAF-induced aggregation, before and after the addition of various concentrations of the examined sample, creating a linear curve of percentage inhibition (ranging from 0% to 100%) versus different concentrations of the sample. The concentration of the sample that inhibited 50% PAF-induced aggregation was calculated based on this curve, and this value was defined as IC50. In addition, the effect of eye drops on PAF metabolism was examined, through an in vitro analysis on PAF basic metabolic enzymes (PAF-cholinephosphotransferase, PAF-acetyl-CoA:1-O-alkyl-sn-glycero-3-phosphocholine acetyltransferase, and PAF-acetylhydrolase).

RESULTS

The IC50 values for Lumigan UD^® (bimatoprost 0.3 mg/mL), Monoprost^® (latanoprost 50 μg/mL), and Saflutan (tafluprost 15 μg/mL) were 8.7, 0.28, and 1.4 μg/mL, respectively.

DISCUSSION

All three prostaglandin analogs suspended PAF, but bimatoprost induced the most potent inhibition, compared to tafluprost and to the weak effect of latanoprost.

The Impact of Non-Steroidal Anti-Inflammatory Agents after Phacoemulsification on Quality of Life: A Randomized Study

Introduction

The purpose of our study was to investigate the impact of ketorolac addition to the well-established combination of antibiotic-steroid agent in terms of vision-related quality of life.

Methods

Patients were randomized to: (1) fixed combination of tobramycin 0.3%–dexamethasone 0.1%, one drop qid (n = 68) and (2) fixed combination of tobramycin 0.3%–dexamethasone 0.1%, one drop qid, plus ketorolac tromethamine 0.5%, one drop tid (n = 70). All patients completed the VFQ-25 questionnaire to assess their functional vision before cataract surgery and postoperatively on days 7, 28 and 42. The statistical analysis comprised the point-wise comparison between the two groups at the four time points for all sub-scales of the VFQ-25 questionnaire, as well as the composite score.

Results

No significant differences were noted regarding the composite score, as well as all subscales in all examined time points.

Conclusions

The addition of ketorolac did not seem to offer any additional benefit in terms of vision-related quality of life.

George Critchett (1817-1882) and His Son George Anderson Critchett (1845-1925)

George Critchett (1817-1882) and his son George Anderson Critchett (1845-1925) have influenced the development of ophthalmology and ocular surgery for about a century. They presented new ocular operations such as Critchett's advancement operation, Critchett's corneal staphyloma operation, and Critchett's keratoconus operation, and they invented new surgical instruments such as Critchett's cataract knife, Critchett's scissors, and Critchett's fixation forceps. Both were delicate ocular surgeons managing complex and difficult surgeries.

Pathophysiology of visual disorders induced by phosphodiesterase inhibitors in the treatment of erectile dysfunction

Aim

The aim of this review was to summarize the ocular action of the most common phosphodiesterase (PDE) inhibitors used for the treatment of erectile dysfunction and the subsequent visual disorders.

Method

This is a literature review of several important articles focusing on the pathophysiology of visual disorders induced by PDE inhibitors.

Results

PDE inhibitors have been associated with ocular side effects, including changes in color vision and light perception, blurred vision, transient alterations in electroretinogram (ERG), conjunctival hyperemia, ocular pain, and photophobia. Sildenafil and tadalafil may induce reversible increase in intraocular pressure and be involved in the development of non-arteritic ischemic optic neuropathy. Reversible idiopathic serous macular detachment, central serous chorioretinopathy, and ERG disturbances have been related to the significant impact of sildenafil and tadalafil on retinal perfusion.

Discussion

So far, PDE inhibitors do not seem to cause permanent toxic effects on chorioretinal tissue and photoreceptors. However, physicians should write down any visual symptom observed during PDE treatment and refer the patients to ophthalmologists.