The role of Visual Evoked Potential (VEP) in monitoring the progression and in guiding the treatment of glaucoma patients with poor compliance.

Objectives: The objectives of the present study were to analyze the possibility of using pattern VEPs (VEP of pattern type) in glaucoma patients and their role in the follow-up and coordination/ management of anti-glaucoma treatment. Patients and Methods: This is a prospective study on 54 eyes of 30 consecutive glaucoma patients, whose compliance capacity did not allow automatic perimetry and OCT scan to be carried out. The patients were divided into two groups: group A - the study group and group B - the control group. All patients underwent FO exam and pachymetry, plus VEP exam for group A patients. Patients were analyzed at the initial visit and at 1 month, 3, 6, 12 months. Statistical analysis was made using t-test, ANOVA, Fisher test and Pearson correlation coefficient. Results: These participants presented a positive correlation between C/ D ratio and the latency of the P100 wave at 1 degree and a negative correlation between C/ D ratio and the amplitude of the P100 wave both at 1 degree (60 arc minutes) and at 0.25 degrees (15 arc minutes). During the study, the values of the latent P100 changed statistically at 6 months and at 1 year. Using all the data, the authors of the study considered it necessary to modify the treatment for 2 patients out of 13 in group B and for 9 patients out of 16 in group A (p = 0,02892). Conclusions: VEP supplies additional/ further data that significantly help guiding the treatment and monitoring the progression, therefore, it should be part of the routine examination for these patients. Further studies are necessary to deepen our understanding of the visual evoked potentials utility.

Visual evoked potential in the early diagnosis of glaucoma. Literature review.

Visual evoked potentials (VEP) are a significant visual electrophysiological diagnostic exam, which can be used as a suitable objective measure of optic nerve function. The topic was greatly debated and many correlations between the magnitude of the VEP latency parameters and parameters of Humphrey static perimetry suggested that the abnormal cortex responses in patients with glaucomatous changes could be tested by both electrophysiological and physical methods. Moreover, the optic nerve glaucomatous damage observed by reduction in ganglion cell layer and retinal fibre layer thickness through SD-OCT tests, which are known to precede Humphrey visual field defects, correlates with VEP latency parameters, thus consolidating the position of the VEP testing in glaucoma progression.

The neuroprotective role of citicoline treatment in glaucoma - 6 months results of a prospective therapeutic trial.

Objectives. Neuroprotective treatment, including citicoline, is a new perspective in glaucoma management, having the role of progression delay. The purpose of the present study was to observe the evolution of the different parameters in patients with glaucoma treated with citicoline. Methods. 22 patients with GPUD were enrolled in the study, and they received oral citicoline in addition to the ocular hypotensive therapy. Investigations were performed at the beginning of the current study, then at 3 months and 6 months, and included, besides full ophthalmologic checkup and IOP determination, optic nerve and RGCs OCT, and visual evoked potentials, pattern and flash. The data we obtained were statistically analyzed with the SPSS (Microsoft) program. Results. The outcomes of the study following VEP wave analysis indicated variations in P100 wave amplitude, but after 6 months period, an increase was found. Also, the P2 wave amplitude recorded statistically insignificant variations. The increase in P2 latency at 6 months was noted as statistically significant. Negative correlations were also met between the thickness of the RGC layer and the P100 latency, but also between the amplitude and the latency of this wave. At 6 months, a positive correlation between the RGC layer and the P100 amplitude was observed. The RNFL thickness at the optical disc had higher values at the 6 months visit, it was statistically significant, and a slight increase in the thickness of the RGC layer between successive visits was noted. These might be an examination artifact because clinically they are not possible. The RNFL thickness showed a positive correlation with the amplitude of P100 and P2 waves. Conclusions. The study of the parameters and their correlations demonstrated that citicoline had positive effects in glaucoma on certain aspects, data confirmed by literature.

The effects of prostaglandins and endocannabinoids on iris arterial vascularization in Wistar rats - Experimental analysis.

Introduction: The iris vascular supply originates in the anterior and long posterior ciliary arteries. The endothelium influences local blood flow by releasing endothelium relaxing and contracting substances. From a functional perspective, the ocular vascular tonus adjustment is humoral and neural dependent. Objectives: The present article aims to evaluate the possible implications of topical administration of selective COX2 and nonselective COX inhibitors generically named nonsteroidal anti-inflammatory drugs (NSAIDs) and their possible interactions with the endocannabinoid system and the way they could interfere with the vascular tone at the level of ocular iris territory in Wistar rats. Materials and methods: Experimental protocol on Wistar rats was performed in accordance with present laws regarding animal welfare and ethics in animal experiments (Directive 86/ 609EEC/ 1986; Romanian Law 205/ 2004; Romanian Laws 206/ 2004, 471/ 2002 and 9/ 2008; Romanian Order 143/ 400). The studied substances were instilled topically under general anesthesia, and images of the rat iris vessels were captured over a period of 10 minutes. The obtained images were further analyzed using an appropriate hardware and software program. Results: The nonselective NSAIDs induced vascular dilation in the iris vessels, while the selective COX2 inhibitors determined a variable degree of vasoconstriction. Conclusion: In view of the results of this experiment and the added evidence found in literature, we consider that further research will show the potential benefits for the additional use of NSAIDs in ocular pathology, otherwise unaffected by this medication until the present time (for example, glaucoma treatment).

Macular pigment density changes in central serous chorioretinopathy.

Aim: To present a series of 2 cases of central serous chorioretinopathy and the changes in the macular pigment optical density during the evolution of the disease. Material and methods: A 32-year-old patient presented himself for blurred vision on his LE. The SD OCT imaging revealed serous macular detachment of the neurosensory retina on the LE. The MPOD results were 0.72 on RE and 0.91 on LE. After treatment and resorption of the subretinal fluid, the MPOD values were 0.72 on the RE and 0.82 on the LE. The second patient was a 36-year-old male with metamorphopsia on LE and serous macular detachment on this eye. The MPOD results were 0.43 on RE and 0.58 on the LE and, after treatment, they were 0.38 on the RE and 0.43 on the LE. Conclusions: Central serous chorioretinopathy is a disease of unknown pathophysiology in which we observed a higher MPOD on the eye with CSC than on the fellow eye and a decrease in the MPOD value after the resorption of the subretinal fluid. Abbreviations: L = lutein, Z = zeaxantin, MZ = mezozeaxantin, AMD = age related macular degeneration, MPOD = macular pigment optical density, MP = macular pigment, HFP = Heterochromatic Flicker Photometry, CSC = central serous chorioretinopathy, RE = right eye, LE = left eye.

Correlations between internal and external ocular factors and macular pigment optical density.

AIM: To assess the relationship between the macular pigment optical density and blue-light issued by computers, glare sensibility, with iris color, age, sex, or refractive errors. MATERIAL AND METHODS: 83 patients (166 eyes) were enrolled in a prospective observational study. They were divided into 2 groups: group 1 (study group) - computer using patients (time spent in front of the computer for minimum 8 hours per day, 5 days per week, 2 years) - 43 patients and group 2 (control group) - 40 patients. The following investigations were conducted in all the selected cases: visual acuity, refraction, biomicroscopy, measurement of the MPOD, glare sensitivity, assessment of eye color. RESULTS: 51.81% of the patients were included in group 1, while the rest, 48.19%, were in group 2. Thus, the MPOD had a mean value of (+/ -SD) 0.42+/ -0.13 (t = -1.08, p = 0.28) in group 1, and 0.44+/ -0.16 on the LE. The results showed a MPOD mean value of 0.51+/ - 0.16 in group 2 and 0.51+/ -0 .16. (t = 0.49, p = 0 .62) on the LE. 55.77% of the patients with light colored iris and 56.14% of those with dark iris had a low MPOD. CONCLUSIONS: The data from our study failed to illustrate a significant correlation between MPOD and blue-light issued by computers. Furthermore, a statistic significant relationship regarding iris color, refractive errors, glare, and MPOD was not observed. ABBREVIATIONS: L = lutein, Z = zeaxanthin, MZ = meso-zeaxanthin, AMD = age related macular degeneration, MPOD = macular pigment optical density, MP = macular pigment, HFP = Heterochromatic Flicker Photometry, RE = right eye, LE = left eye.

Topical administration of Metamizole and its implications on vascular reactivity in Wistar rats- Experimental research.

Aim: The aim of this paper was to describe the possible implications of topical (ocular) administration of Metamizole on vascular reactivity of the iris in Wistar rats. No other study regarding its topical use was found. Methods: Male adult Wistar rats were anaesthetized with Ketamine 100 mg /kg body weight - injected intraperitoneally - while maintaining spontaneous respiration and the blink reflex. After selecting the area of interest (long posterior ciliary artery - LPCA), manual adjustments of the image magnitude, clarity, and brightness were made, and the experiment began. The image recording lasted 10 minutes. Results: Metamizole induced a slight vasoconstriction that started with the initial moment for all the doses used. After the topical administration of Metamizole, we did not observe an increase of the vascular diameter of LPCA in a dose dependent manner. The saline solution used as a negative control did not modify the vessel diameter. Conclusions: Metamizole (dipyrone) is a non-opioid drug, which is commonly used in human and veterinary medicine. It is the most popular first-line analgesic in various populations. In some cases, this agent is still incorrectly classified as a non-steroidal anti-inflammatory drug. The high analgesic efficacy of metamizole, as well as its spasmolytic effect, makes it a very important pharmaceutical agent that could be used in the therapy of various eye disorders in humans and in animals. Abbreviations: COX = Cyclooxygenase; LPCA = Long Posterior Ciliary Artery; PRP = panretinal photocoagulation; PDR = proliferative diabetic retinopathy; Sec = second(s); VSPR = very severe non proliferative diabetic retinopathy.

[Panuveitis--difficulties in diagnosis and treatment]. / Panuveita--dificultati de diagnostic si tratament.

We report the case of a young patient who had a past history of HSV encefalitis and presented for decreased vision in her left eye associated with pain and red eye.