Specific molecular peak analysis by ion mobility spectrometry of volatile organic compounds in urine of COVID-19 patients: A novel diagnostic approach.

INTRODUCTION: SARS-CoV-2 is usually diagnosed from naso-/oropharyngeal swabs which are uncomfortable and prone to false results. This study investigated a novel diagnostic approach to Covid-19 measuring volatile organic compounds (VOC) from patients' urine. METHODS: Between June 2020 and February 2021, 84 patients with positive RT-PCR for SARS-CoV-2 were recruited as well as 54 symptomatic individuals with negative RT-PCR. Midstream urine samples were obtained for VOC analysis using ion mobility spectrometry (IMS) which detects individual molecular components of a gas sample based on their size, configuration, and charge after ionization. RESULTS: Peak analysis of the 84 Covid and 54 control samples showed good group separation. In total, 37 individual specific peaks were identified, 5 of which (P134, 198, 135, 75, 136) accounted for significant differences between groups, resulting in sensitivities of 89-94% and specificities of 82-94%. A decision tree was generated from the relevant peaks, leading to a combined sensitivity and specificity of 98% each. DISCUSSION: VOC-based diagnosis can establish a reliable separation between urine samples of Covid-19 patients and negative controls. Molecular peaks which apparently are disease-specific were identified. IMS is an additional non-invasive and cheap device for the diagnosis of this ongoing endemic infection. Further studies are needed to validate sensitivity and specificity.

Alpha1-antitrypsin deficiency in Greece: Focus on rare variants.

PURPOSE: A1Antitrypsin deficiency (AATD) pathogenic mutations are expanding beyond the PI*Z and PI*S to a multitude of rare variants. AIM: to investigate genotype and clinical profile of Greeks with AATD. METHODS: Symptomatic adult-patients with early-emphysema defined by fixed airway obstruction and computerized-tomography scan and lower than normal serum AAT levels were enrolled from reference centers all over Greece. Samples were analyzed in the AAT Laboratory, University of Marburg-Germany. RESULTS: Included are 45 adults, 38 homozygous or compound heterozygous for pathogenic variants and 7 heterozygous. Homozygous were 57.9% male, 65.8% ever-smokers, median (IQR) age 49.0(42.5-58.5) years, AAT-levels 0.20(0.08-0.26) g/L, FEV1(%predicted) 41.5(28.8-64.5). PI*Z, PI*Q0, and rare deficient allele's frequency was 51.3%, 32.9%,15.8%, respectively. PI*ZZ genotype was 36.8%, PI*Q0Q0 21.1%, PI*MdeficientMdeficient 7.9%, PI*ZQ0 18.4%, PI*Q0Mdeficient 5.3% and PI*Zrare-deficient 10.5%. Genotyping by Luminex detected: p.(Pro393Leu) associated with MHeerlen (M1Ala/M1Val); p.(Leu65Pro) with MProcida; p.(Lys241Ter) with Q0Bellingham; p.(Leu377Phefs*24) with Q0Mattawa (M1Val) and Q0Ourem (M3); p.(Phe76del) with MMalton (M2), MPalermo (M1Val), MNichinan (V) and Q0LaPalma (S); p.(Asp280Val) with PLowell (M1Val); PDuarte (M4), YBarcelona (p.Pro39His). Gene-sequencing (46.7%) detected Q0GraniteFalls, Q0Saint-Etienne, Q0Amersfoort(M1Ala), MWürzburg, NHartfordcity and one novel-variant (c.1A>G) named Q0Attikon.Heterozygous included PI*MQ0Amersfoort(M1Ala), PI*MMProcida, PI*Mp.(Asp280Val), PI*MOFeyzin. AAT-levels were significantly different between genotypes (p = 0.002). CONCLUSION: Genotyping AATD in Greece, a multiplicity of rare variants and a diversity of rare combinations, including unique ones were observed in two thirds of patients, expanding knowledge regarding European geographical trend in rare variants. Gene sequencing was necessary for genetic diagnosis. In the future the detection of rare genotypes may add to personalize preventive and therapeutic measures.

Diabetic Macular Edema - Diagnostics and Treatment Guidelines.

Together with diabetic retinopathy, diabetic macular edema (DME) ranks among the most common causes of severe loss of vision in working adults. Due to recent developments in imaging methods, new classification schemes of DME have been created. In addition to this, new treatment options have been introduced (new intravitreal drugs as well as treatment protocols). At the same time laser, surgical as well as combination therapy is still available. In this paper we evaluate the current knowledge about DME diagnostic and treatment options and formulate recommended guidelines for the management of DME.

LASER VITREOLYSIS IN PATIENTS WITH SYMPTOMATIC VITREOUS FLOATERS.

AIMS: To examine the effectiveness and safety of Nd:YAG laser vitreolysis in patients with symptomatic vitreous floaters. MATERIAL AND METHODS: This was a single-centre study of adult patients with symptomatic vitreous floaters who underwent laser vitreolysis. Patients treated between 1/2020 and 10/2021 were included. Intraocular pressure was measured by non-contact tonometry before and one month after treatment. Colour fundus photography, slit lamp examination in mydriasis, best corrected visual acuity, optical coherence tomography, and ultrasound examinations were performed before treatment. The patients completed a questionnaire to subjectively rank the degree of impairment associated with the floaters before and between 1 and 2 months after treatment. RESULTS: 89 eyes from 84 patients were included in the study, with a slight predominance of women (53%). A Weiss ring was present in 46%, and other types of vitreous opacity were found in 54%. Before treatment, 69% evaluated floaters as very troublesome (i.e., a value of 4 or 5 on a 1-5 scale). After treatment, 42% indicated subjective improvement (9% viewed the treatment as a complete success and 33% as a significant success). In 33% of eyes there was a partial improvement, i.e., some floaters could still be seen, and in 17% there was no improvement; 8% of patients were dissatisfied with the treatment results. There was no statistically significant difference in improvement between the group with Weiss rings and the group with other types of floaters. The procedure itself and the subsequent observation period were without complications, i.e., no cases of intraocular pressure elevation, cataract formation or retinal complications. Intraocular pressure did not significantly change from the pre-procedure value (p = 0.29). Average best corrected visual acuity after treatment was 0.97, thus it did not differ significantly from the pre-treatment values (p = 0.82). CONCLUSION: Nd:YAG laser vitreolysis subjectively improved floater-related symptoms in treated eyes. The lack of an objective measurement of treatment success is a limiting factor. Laser vitreolysis is more suitable for solitary than diffuse vitreous opacities.

EFFECT OF BASELINE CENTRAL RETINAL THICKNESS ON THE RESULTS OF TREATMENT OF DIABETIC MACULAR EDEMA WITH AFLIBERCEPT: REAL-LIFE EVIDENCE IN THE CZECH REPUBLIC.

AIM: Presentation of the 1-year results of aflibercept treatment in patients suffering from diabetic macular edema (DME) and comparison of the response to treatment of patients with different baseline central retinal thickness (CRT). METHODS: This was a multicentre, retrospective observational study of a series of cases. Patients with DME were treated in a fixed regimen (5 injections at 1-monthly intervals and then injections at 2-monthly intervals). The period of follow-up was 12 months. The development of best corrected visual acuity (BCVA) and CRT was evaluated. Measurements were performed prior to the commencement of treatment and then after 4, 6, 8, 10, and 12 months. RESULTS: The therapeutically naive group consisted of 82 eyes of 79 patients. The total cohort of patients was divided into 3 groups according to the baseline values of CRT. The first group was composed of 28 eyes with baseline CRT < 450 μm (34.1%), the second included 25 eyes with CRT in the range of 450-550 μm (30.5%), and the third group consisted of 29 eyes with baseline CRT > 550 μm (35.4%). The average baseline BCVA and SD in the first group was 66 ±7.1 letters ETDRS optotypes, and then 70 ±7 letters, 69.6 ±7.3 letters, and 71.3 ±7 letters at the follow-ups after 4, 8, and 12 months. The average baseline value of CRT and SD in the first group was 379 ±48.6 μm, and then 337.1 ±76.5 μm, 320.2 ±74.1 μm, and 315.1 ±62.2 μm after 4, 8, and 12 months. The average baseline BCVA and SD in the second group was 64.1 ±9.7 ETDRS letters, and then 66.9 ±10 letters, 70 ±9.9 letters, and 70.5 ±11.5 letters after 4, 8, and 12 months. The average baseline value of CRT and SD in the second group was 497.4 ±76.4 μm, and then 376.5 ±106.1 μm, 360.8 ±70 μm, and 351.3 ±91.3 μm after 4, 8, and 12 months. In the third group, the average baseline value of BCVA and SD was 59.7 ±10.4 ETDRS letters, and then 65 ±10.6 letters, 64.8 ±9.6 letters, and 67 ±10 letters after 4, 8, and 12 months. The average baseline value of CRT and SD in the third group was 639.4 ±79.6 μm, and then 396.7 ±147.1 μm, 416.9 ±139.8 μm, and 368.5 ±109.9 μm after 4, 8, and 12 months. All these changes were statistically significant (p < 0.05). CONCLUSION: Aflibercept treatment in a fixed regimen in patients suffering from DME results in a statistically significant improvement in BCVA and a decrease in CRT in the first year of treatment. Patients with a higher baseline CRT showed the best anatomical and functional results of the 1-year treatment with aflibercept.

INTRAVITREAL RANIBIZUMAB IN PREGNANT PATIENT WITH MYOPIC CHOROIDAL NEOVASCULAR MEMBRANE. A CASE REPORT.

AIM: To present the case of a patient with myopic choroidal neovascular membrane (mCNV) in the 3rd trimester of pregnancy, who was treated with intravitreal ranibizumab. CASE REPORT: The 34-year-old patient was referred to the Department of Ophthalmology of the University Hospital Kralovske Vinohrady in January 2020 for mCNV on her right eye (RE). The patient was in the 34th week of pregnancy. Initial best corrected visual acuity (BCVA) was 68 ETDRS letters. Spherical equivalent of the RE was -11.5 dioptres, axial length of the RE was 27.7 mm. Pigmented CNV with small haemorrhage was present on the retina of the RE. Optical coherence tomography (OCT) of the RE showed a hyperreflective mass above the retinal pigment epithelium, central retinal thickness (CRT) was 310 µm. OCT angiography confirmed the presence of a classic CNV in the macula of the RE. Two weeks later, the hyperreflective lesion and oedema in the macula of the RE increased, the CRT was 329 µm, BCVA remained stable. After discussion with the patient and the treating gynaecologist, intravitreal ranibizumab was administered in the RE in the 36th week of pregnancy. On check-up 3 weeks later, we observed the decrease of macular oedema to 276 µm and the improvement of BCVA to 78 ETDRS letters. The patient delivered a healthy baby girl in the 39th week of pregnancy via caesarean section, postnatal adaptation of the newborn was normal. During further visits, the BCVA improved to 83 ETDRS letters and the macular oedema disappeared completely. 8 months after the first ranibizumab injection, the CNV reactivated, BCVA decreased to 72 ETDRS letters, oedema was present in the macula and the CRT was 309 µm. Another ranibizumab was administered into the RE. The patient then discovered that she was pregnant; according to calculations, she was in the 3rd week of pregnancy at the time of the second ranibizumab injection. After the second injection, BCVA improved to 79 ETDRS letters, macular oedema on the OCT disappeared and CRT decreased to 264 µm. The pregnancy was terminated per patients request. CONCLUSION: Intravitreal administration of ranibizumab in the 3rd trimester of pregnancy led to the improvement of BCVA and decrease of macular oedema in the patient with mCNV. The injection had no adverse effect on the pregnancy or the postnatal adaptation of the newborn. However, it is always necessary to consider the risk/benefit ratio when administering intravitreal antiVEGF drugs in pregnant patients. Thorough discussion with the patient is necessary.

ARTEFICIAL INTELLIGENCE IN DIABETIC RETINOPATHY SCREENING. A REVIEW.

OBJECTIVE: The aim of this comprehensive paper is to acquaint the readers with evaluation of the retinal images using the arteficial intelligence (AI). Main focus of the paper is diabetic retinophaty (DR) screening. The basic principles of the artificial intelligence and algorithms that are already used in clinical practice or are shortly before approval will be described. METHODOLOGY: Describing the basic characteristics and mechanisms of different approaches to the use of AI and subsequently literary minireview clarifying the current state of knowledge in the area. RESULTS: Modern systems for screening diabetic retinopathy using deep neural networks achieve a sensitivity and specificity of over 80 % in most published studies. The results of specific studies vary depending on the definition of the gold standard, number of images tested and on the evaluated parameters. CONCLUSION: Evaluation of images using AI will speed up and streamline the diagnosis of DR. The use of AI will allow to keep the quality of the eye care at least on the same level despite the raising number of the patients with diabetes.

UVEAL EFFUSION SYNDROME. CASE REPORT.

PURPOSE: Purpose of this article is to present a case report of a patient with uveal effusion syndrome who underwent deep posterior sclerotomy. CASE REPORT: A 73-year-old patient with unilateral decrease in the best corrected visual acuity, ablation of choroid and secondary retinal detachment in the right eye was admitted to our clinic for examination in November 2017. At the first examination, the best corrected visual acuity in the right eye was 0.3, in the left eye 1.0. Intraocular pressure was 16 mmHg in the right eye and 21 mmHg in the left eye. After performing ultrasound biomicroscopy of the anterior segment (Accutome, Keeler, USA), ultrasound sonography of the affected eye (Accutome, Keeler, USA), magnetic resonance imaging, computed tomography, abdominal ultrasound and blood tests, we concluded the finding as uveal effusion syndrome. We initiated a conservative treatment consisting of oral administration of carbonic anhydrase inhibitor in combination with topical use of prostaglandin analogue. Despite conservative treatment the best corrected visual acuity of the affected eye decreased to 0.05 so we proceeded to a surgical procedure - deep posterior sclerotomy with perioperative scleral sampling for histological examination (detection of glycosaminoglycans in the sclera wall by Alcian blue staining), which was negative. This histological result ranks the patient as the third type of uveal effusion syndrome (ie, non-nanophthalmic with a normal sclera). After the operation both the ablation of choroid and retinal detachment reattached and the best corrected visual acuity in the right eye improved to 0.3. After the subsequent cataract surgery, the ablation of choroid and retinal detachment occurred again, this time with spontaneous recovery. Postoperatively, the best corrected visual acuity in the right eye was 0.5 and at the last check-up at our clinic 0.6. CONCLUSION: Deep posterior sclerotomy is a method of choice of surgical treatment for uveal effusion syndrome that does not respond to conservative therapy.

Unequal sisters - Past and potential future range development of Anatolian and Hyrcanian brown frogs.

Phylogeography can reconstruct historical evolutionary processes by comparing historical patterns of gene flow, divergence among species and by using species distribution models (SDM) upon geographic distribution. We investigate the phylogeographic patterns of Anatolian brown frogs including R. macrocnemis and R. tavasensis as well as the Hyrcanian brown frog, R. pseudodalmatina, using a fragment of the mitochondrial 16S rRNA gene for 145 specimens across the entire range of these frogs. We calculate parameters of molecular diversity, such as the number of variable sites (S), the number of haplotypes (h), haplotype diversity (Hd) and nucleotide diversity (π). We generated a haplotype network and used three methods (Neutrality tests, mismatch distributions and Bayesian skyline plots) to reconstruct the demographic histories of R. macrocnemis and R. pseudodalmatina. Finally, we used SDMs to predict the habitat suitability for three periods: The Present Day, the Last Glacial Maximum (LGM) and the future until 2070 for R. macrocnemis and R. pseudodalmatina. Our phylogenetic analyses support a late Miocene origin of Anatolian and Hyrcanian lineages. Hyrcanian brown frogs were enclosed in lowlands of the southern coast of the Caspian Sea after the uplift of the Elburz range and the Armenian plateau. The formation of a salinity belt from the north Aegean corridor (the south western Turkey) to northward during the Late Tortonian led to the subdivision of ancestor of the Anatolian lineage into today isolated western and eastern populations. The salinity belt had a considerable impact on the divergence of R. tavasensis from R. macrocnemis. Combined historical demographic analyses and SDMs revealed a rapid expansion occurring during the Pleistocene in R. macrocnemis and R. pseudodalmatina. Currently, suitable habitat for R. macrocnemis has declined compared to the LGM, and the species is predicted to do even worse under future climatic conditions. In contrast, R. pseudodalmatina found suitable habitat from the LGM to present within its restricted distribution area; it is predicted to do fine even under future climate.

Innovative strategies for treating retinal diseases.

OBJECTIVE: The aim of this comprehensive paper is to acquaint the readers with innovative approaches in the treatment of retinal diseases, which could in the coming years to get into clinical practice. Retinal prostheses, retinal pigment epithelial (RPE) transplantation, gene therapy and optogenetics will be described in this paper. METHODOLOGY: Describing the basic characteristics and mechanisms of different types of therapy and subsequently literary minireview clarifying the current state of knowledge in the area. RESULTS: Retinal prostheses, RPE transplantation, gene therapy and optogenetics offer yet unexplored possibilities and are considered as the future of treatment of retinal diseases where classical pharmacotherapy or surgical treatment are no longer sufficient. However, all these methods challenge not only in the innovative technical implementation itself, but also for the ethical, administrative and economic demands. CONCLUSION: There will be certainly interesting development in the treatment of retinal diseases, but it is not possible to fully estimate which modality of treatment will be dominant in the future.

Surgical Treatment of Idiopathic Macular Hole Using Different Types of Tamponades and Different Postoperative Positioning Regimens.

PURPOSE: To compare the effect of different types of intraocular tamponade and different types of postoperative positioning on the closure of idiopathic macular hole (IMH). METHODS: Prospective randomized clinical trial enrolling 104 eyes of 100 patients (age, 57-87 years) undergoing MH surgery. All patients were operated on by an experienced surgeon using 25-gauge pars plana vitrectomy (PPV) and internal limiting membrane (ILM) peeling. Patients were randomized according to the type of intraocular tamponade and postoperative positioning into the following four groups: SF6 + nonsupine reading position (n = 26) (group 1), air + nonsupine reading position (n = 25) (group 2), air + prone position (n = 26) (group 3), or SF6 + prone position (n = 27) (group 4). The follow-up period was 6 months. RESULTS: MH closure was achieved in 87 eyes (83.7 %) in the overall sample after the first surgery, with closure rates of 100%, 56%, 84.6%, and 92.6% in groups 1, 2, 3, and 4, respectively. The group 2 was significantly less successful compared to the other three groups (p < 0.05). MH of sizes ≤400 µm was closed in 97.2% of cases after the first surgery, with no significant differences between groups (p = 0.219). MH with sizes over 400 µm was closed in 70.9% of cases after the first surgery, with both groups with air tamponade being significantly less successful than group 1. The nonsupine reading position was subjected to a better subjective evaluation in terms of postoperative comfort and quality of sleep, with no differences between air and SF6 tamponade tolerance. CONCLUSION: PPV with ILM peeling, intraocular tamponade, and positioning remains the basic surgical approach in the treatment of IMH. For MH ≤ 400 µm, a high closure rate can be achieved by combining air tamponade and nonsupine reading position. For macular holes >400 µm, the greatest anatomical success can be achieved by using the SF6 tamponade in combination with the nonsupine reading position.

Treatment of Vitreomacular Traction with Intravitreal Injection of Perfluoropropane.

PURPOSE: To evaluate the effect of one intravitreal injection of expansile gas in the treatment of vitreomacular traction (VMT). METHODS: A retrospective review of eyes with VMT treated with singl injection of 0,3 ml of 100% C3F8 gas was performed. The procedure was performed on an outpatient basis under topical anesthesia. RESULTS: Twelve consecutive patient (14 eyes) with symptomatic VMT underwent pneumatic vitreolysis. Mean extend of vitreomacular adhesion was 490,5 µm (408-751). A posterior vitreous detachment developed in 13 eyes (92,9 %) after a single gas injection, in 11 eyes (84,6 %) during the first month of follow-up, in 2 eyes within two month of injection. Mean baseline and last BCVA were 0,5 (0,16-0,18) and 0,67 (0,2-1,0) respectively (p.

ONE-YEAR FOLLOW-UP OUTCOMES OF TREATMENT OF WET AGE-RELATED MACULAR DEGENERATION WITH AFLIBERCEPT.

PURPOSE: To evaluate one-year follow-up outcomes of treatment with aflibercept in patients with newly diagnosed wet age-related macular degeneration (ARMD). METHOD: Retrospective evaluation of treatment of 28 eyes of 28 patients with an average age of 74.2 years who were treated with aflibercept at the Department of Ophthalmology at Královské Vinohrady University Hospital. All patients were treated according to the summary of product characteristics (SPC), i.e. with an initial 3 injections at monthly intervals, followed by 4 injections every 2 months. We evaluated the change in best corrected visual acuity (BCVA) on Early Treatment of Diabetic Retinopathy Study (ETDRS) optotypes, and the change of central retinal thickness (CRT) with the aid of optical coherence tomography (OCT). RESULTS: The average initial BCVA value was 61.5 letters of ETDRS optotype. After the initial 3 injections, BCVA improved to 70.5 letters, after one year of treatment there was a slight decrease to 68.1 letters. Better or same visual acuity was recorded in 25 eyes (89.3%), a deterioration occurred in 3 eyes (10.7%). CRT was reduced from an initial average value of 360.9 µm to 253.3 µm after the initial phase and to 233.8 µm after one year of treatment. At the end of the observation period, 25 eyes (89.3%) were without signs of activity of the pathology. No complications of treatment were recorded. CONCLUSION: In our cohort we confirm the efficacy and safety of the aflibercept preparation in patients with newly diagnosed wet form ARMD. By adhering to a fixed therapeutic regime it is possible to obtain similarly excellent results of treatment in real clinical practice as in clinical trials. Key words: aflibercept, anti-VEGF therapy, optical coherence tomography, wet form ARMD The authors of the study declare that no conflict of interest exists in the compilation, theme and subsequent publication of this professional communication, and that it is not supported by any pharmaceuticals company.

Results of the first 12 months treatment of macular edema complicating BRVO in patients treated with ranibizumab.

THE AIM OF THE STUDY: Retrospective evaluation of the first 12 months treatment of macular edema in BRVO with ranibizumab based on anatomical and functional parameters. METHODS: 54 eyes with macular edema complicating BRVO were included in the study, with an average initial best corrected visual acuity 4/16 ETDRS charts, an average central retinal thickness 512.3 µm, and in average 4 months till the beginning of treatment with ranibizumab. After 3 initial injections of 0.5 mg ranibizumab treatment was performed in pro re nata regimen, with adjuvant laser (grid laser photocoagulation) as an additional treatment option.  The number of injections administered, the number of eyes where grid laser photocoagulation was provided, functional parameters as a letter gain and BCVA (eyes with final BCVA ≥ 4/8 ETDRS, final BCVA in according to initial BCVA) and anatomical parameters as a mean CRT and  CRT ≤ 250 µm, respectively ≤ 300 µm were evaluated. RESULTS: In the whole group, an average of 4.8 injections of ranibizumab were administered in the first 12 months. Grid laser photocoagulation was performed in 42 eyes: in 8 eyes prior to the beginning of treatment with ranibizumab, 7 eyes before and during the treatment, 29 eyes only during the treatment. The main gain of letters after 12 months of treatment was +16.5 letters, with 63¨% (n = 34) eyes earning ≥ 15 letters. In the whole group 72 % (n = 39) eyes achieved the resulting BCVA ≥ 4/8 ETDRS after 12 months of treatment. The eyes with initial BCVA ≥ 4/10 ETDRS resulted in BCVA ≥ 4/8 ETDRS in 96 % (n = 23 eyes) and 11 eyes even  achieved BCVA ≥ 4/4. The mean CRT after 12 months of treatment was 290.3 µm, 33.3 %  of eyes had final CRT ≤ 250 µm, and 64.8 % had final CRT ≤ 300 µm. CONCLUSION: When applying a relatively low number of injections in the first year of treatment with ranibizumab, the final best corrected visual acuity was very good at the end of the observation period, and its dependence on the initial best corrected visual acuity was confirmed. Satisfactory results of central retinal thickness were found as well. Key words: branch retinal vein occlusion, macular edema, ranibizuma.

Extreme tuning of wetting on 1D nanostructures: from a superhydrophilic to a perfect hydrophobic surface.

The tuning of wetting over an extreme range, from superhydrophilic to superhydrophobic, was demonstrated on 1D Al/Al2O3 nanostructures. While chaotic and tangled 1D Al/Al2O3 nanostructures exhibited complete wetting, they became water repellent (with a water contact angle (CA) ≥173°) after the infiltration of poly[bis(2,2,2-trifluoroethoxy)phosphazene] (PTFEP) solution. This simple strategy allows the achievement of two extreme wetting regimes, perfect wetting and non-wetting, without altering the nanostructured surface topography. The same surface was also found to exhibit repellency towards artificial blood and hexadecane.

[Surgical Treatment of the Idiopathic Macular Hole by Means of 25-Gauge Pars Plana Vitrectomy with the Peeling of the Internal Limiting Membrane Assisted by Brilliant Blue and Gas Tamponade]. / Chirurgické resení idiopatické makulární díry 25-gauge pars plana vitrektomií s peelingem vnitrní limitující membrány asistované briliantovou modrí a plynovou tamponádou.

UNLABELLED: 25-gauge pars plana vitrectomy with briliant blue assisted internal limiting membrane peeling and gas tamponade for idiopatic macular hole. PURPOSE: The evaluation of anatomic and visual outcomes in idiopatic macular holes treated with 25-gauge pars plana vitrectomy, briliant blue (BB) assisted internal limiting membrane (ILM) peeling and gas tamponade. MATERIALS AND METHODS: Retrospective analysis. 53 eyes of 52 patients (39 women, 13 men) of mean age 68,8 years (58-83) with the diagnosis of stage 2, 3, or 4 macular holes according to Gass Classification from 6/2012 to 7/2014 were included. All patient undergone 25-gauge pars plana vitrectomy with brillinat blue assisted ILM peeling, gas tamponade (35 cases 15 % C3F8, 18 cases 20% SF6). 50 cases (94,3%) were performed in retrobulbar anesthesia, 3 cases in general anesthesia. Face-down positioning should have beeen maintained for three days. Best corrected visual acuity (BCVA), optical coherence tomography findings and complications were evaluated. RESULTS: The mean follow-up time was 6 months (1-22). Macular hole closure was achieved in 49 eyes (92,5%). The mean BCVA improved from 0,16 (0,5-0,05) to 0,5 (1,0-0,1). BCVA was improved by 3 and more ETDRS lines in 42 eyes (79,2%). CONCLUSION: 25-gauge pars plana vitrectomy with briliant blue assisted internal limiting membrane peeling and gas tamponade is safe and effective method of macular hole therapy with high anatomic and functional effect.

3D and 2D structural characterization of 1D Al/Al2 O3 biphasic nanostructures.

1D Al/Al2 O3 nanostructures have been synthesized by chemical vapour deposition (CVD) of the molecular precursor [(t) BuOAlH2 ]2 . The deposited nanostructures grow chaotically on the substrate forming a layer with a high porosity (80%). Depending on the deposition time, diverse nanostructured surfaces with different distribution densities were achieved. A three-dimensional (3D) reconstruction has been evaluated for every nanostructure density using the Focus Ion Beam (FIB) tomography technique and reconstruction software tools. Several structural parameters such as porosity, Euler number, geometrical tortuosity and aspect ratio have been quantified through the analysis with specified software of the reconstructions. Additionally roughness of the prepared surfaces has been characterized at micro- and nanoscale using profilometry and AFM techniques, respectively. While high aspects ratio around 20-30 indicates a strong anisotropy in the structure, high porosity values (around 80%) is observed as a consequence of highly tangled geometry of such 1D nanostructures.

[Contrast sensitivity and optic coherence tomography examinations in adolescent patients with diabetes type I preretinopathy (a pilot study)]. / Preretinopatie u mladistvých s diabetem 1. typu z pohledu vysetrení citlivosti na kontrast a koherencní tomografie (pilotní studie).

AIM: To evaluate the development of retinal changes in adolescent patients with diabetes type I (T1DM) with diseases duration more than 10 years, which started before 5 years of age. METHODS: The development of the findings on the posterior pole was followed up. The retinal functions were established by means of contrast sensitivity in four space frequencies: 3 cycles/degree (c/deg) (perimacular area), 6 c/deg and 12 c/deg (macular area), and, finally, 18 c/deg (foveola). The central retinal thickness, average retinal thickness of the specified quadrant of macular area, the foveolar depth of its own, and the volume of the perimacular area (perimacular cube volume) were measured by means of optical coherent tomography (OCT). MATERIAL: Altogether 20 patients with diabetes type I meeting the set criteria were examined, and their findings were compared with control group of healthy adolescent people. The values from the control group were used as our normative database. RESULTS: On the retina, there were found, during the diseases course lasting in average 13.3 years, changes of the macular area, especially tortuosity of macular final capillaries and pigmentation with disappearing of foveolar reflex, which, in 20 %, were followed by sporadic hard exsudates of the retina. Difference of the decreased values in adolescent patients, comparing to the control group, was recorded in contrast sensitivity in space frequencies of 3 c/deg (p 0.047) and 12 c/deg (p 0,0497), but statistically significant was the difference in space frequencies of 6 c/deg (p 0.0001) and 18 c/deg (p 0.0001). Using the OCT, no statistically significant difference was found in the central retinal thickness, but the values of foveolar depth in patients with diabetes type I were variable (p 0.0153); in four eyes it was much deeper, and in other four of them it was much shallower. Furthermore, there was higher the average thickness of the retina (p 0.0008) and the volume of the perimacular area (perimacular cube) (p 0,0001). CONCLUSION: The findings in eight eyes out of five patients with T1DM were evaluated as diabetic preretinopathy - pre-stage of beginning stage of diabetic retinopathy in central area of the retina from the functional and structural point of view of current pathological changes of contrast sensitivity and OCT. The findings of other three patients were rated as diabetic preretinopathy according to sporadic hard exsudates of the retina and OCT changes, but. until now, without contrast sensitivity changes. The one-year profile of glycated hemoglobin (HbA1c) was higher in patients with diabetic preretinopathy than without the eye involvement, but it was not statistically significant (p 0,0314).Key words: Contrast sensitivity (CS), Spectral Domain Optic Coherence Tomography (SD-OCT), diabetes mellitus type I (T1DM), diabetic preretinopathy (DpR), glycated hemoglobin (HbA1c).

[The incidence of endophtalmitis after the application of intravitreal injections in FNKV with regard to various prophylactic antibiotic regimens]. / Výskyt endoftalmitidy po aplikaci intravitreálních preparátu na Oftalmologické klinice FNKV s ohledem na ruzné profylaktické ANTIBIOTICKÉ rezimy.

AIM: Comparing the incidence of endophtalmitis at the Ophthalmologic clinic of FNKV after the application of intravitreal injections with regard to various prophylactic antibiotic regimens.Methodics: Comparing the number of endophtalmitis cases during the period of 2005-2011, when the intravitreal applications were secured by full antibiotic prophylaxis (Floxal)/Oftaquix gtt. 5xd 3 days before the application and 3 days after the application with the years of 2012-2013, when Vigamox gtt. was used during the preparation of the eye before surgery to prevent inflammatory changes. RESULTS: In the years of 2005-2013, 5005 injections were applied. In total we recorded three cases of endophthalmitis. In all cases, a pars plana vitrectomy with sample collection for culture and microbiological analysis was performed. During the years of 2005-2011, 2 651 injections were applied with two cases of endophtalmitis (0,075%, 1:1 325, both cases culture-negative). During the years of 2012-2013, 2 355 injections were applied with one case of endophtalmitis (0,042 %, 1:2 355, culture-positive). CONCLUSION: According to our experience, limited prophylactic antibiotic regimen does not increase the incidence of endophtalmitis in comparison with full prophylactic antibiotic regimen.