Vitamin A Deficiency, COVID-19, and Rhino-Orbital Mucormycosis (Black Fungus): An Analytical Perspective.

Mucormycosis is a rare but serious opportunistic fungal disease characterized by rhino-orbito-cerebral and pulmonary involvement. It is mainly seen in people with secondary immunosuppression, isolated vitamin A deficiency, measles, and AIDS patients. It showed a rise during the second wave of the COVID-19 epidemic in the spring of 2021 in India, especially in diabetic COVID-19 patients. Vitamin A deficiency is known to cause nutritional immunodeficiency and hence leading the way to increased opportunistic fungal, bacterial, and viral infections. In the eye, it causes keratitis, night blindness, xerophthalmia, conjunctivitis, Bitot spots, keratomalacia, and retinopathy. It also causes decreased tear secretion and deterioration of the anatomical/physiological defense barrier of the eye. The negative impact of vitamin A deficiency has been previously demonstrated in measles, AIDS, and COVID-19. We think that mucormycosis in COVID-19 might be rendered by vitamin A deficiency and that vitamin A supplementation may have preventive and therapeutic values against mucormycosis and other ocular symptoms associated with COVID-19. However, any vitamin A treatment regimen needs to be based on laboratory and clinical data and supervised by medical professionals.

Associations between red reflex abnormality, consanguinity and intensive care hospitalization of newborns in Turkey.

BACKGROUND: Red reflex screening is the primary but unheeded test for the detection of vision- and life-threatening eye conditions. AIMS: To evaluate the red reflex of newborns, percentage of ocular diseases resulting in red reflex abnormality, and their relation with consanguinity in Southeast Turkey. METHODS: Newborns (n = 1358) were examined with pencil light and direct ophthalmoscopy. RESULTS: Eight hundred of these newborns were hospitalized in a rooming-in unit. (RIU) and 558 were in the neonatal intensive care service (NICS). In the RIU there were 7 (0.88%) newborns with abnormal red reflex and in the NICS there were 14 (2.51%). Sensitivity of pencil light examination was 71.4%. Studies from the Middle East have shown potential recessive genetic causes of common paediatric ocular conditions. In our study, consanguineous marriage was found to have a significant association with red reflex abnormality (P = 0.017). CONCLUSIONS: Red reflex screening test is important in the early diagnosis of vision- and life-threatening eye disorders in Southeast Turkey where consanguinity is common.

Brimonidine-timolol versus brinzolamide-timolol for treatment of elevated intraocular pressure after phacoemulsification surgery.

PURPOSE: To compare the efficacy of the fixed combination of brimonidine-timolol (FCBT) and the fixed combination of brinzolamide-timolol (FCBZT) treatments for elevated intraocular pressure (IOP) after phacoemulsification cataract surgery. METHODS: A randomised, prospective, double-blinded study was conducted on 277 eyes of 257 patients who underwent phacoemulsification cataract surgery. Patients were divided into three groups based on the medication administered after cataract surgery as follows: FCBT, FCBZT and a control group where no antiglaucoma medications were used. IOP was recorded at preoperative and postoperative hours 6 and 24 and days 3 and 5. RESULTS: No statistical differences were observed among the groups regarding age, sex and baseline IOP levels (p > 0.05). Mean IOP levels were significantly lower in the treatment groups than in the control group at postoperative hours 6 and 24 and days 3 and 5 (p < 0.001). Administration of one drop of FCBT or FCBZT demonstrated similar effects on preventing IOP spikes within 24 h of phacoemulsification cataract surgery. FCBZT more effectively lowered IOP than FCBT at days 3 and 5 (p < 0.05). CONCLUSIONS: We demonstrate that the postoperative administration of FCBT or FCBZT is effective in lowering IOP after phacoemulsification cataract surgery; FCBZT more effectively lowered IOP than FCBT at postoperative days 3 and 5.

Activation of toxoplasma retinochoroiditis during pregnancy and evaluation of ocular findings in newborns.

The purpose of this study was to evaluate patients with activation of toxoplasma retinochoroiditis during pregnancy and ocular findings in newborns. A total of 17 pregnant patients who were clinically and serologically diagnosed with ocular toxoplasmosis were retrospectively reviewed. After birth, ocular findings for all infants were recorded. The mean age of the patients was 29.08 ± 5.71 years. In all cases, activation was present in only one eye. In 13 cases, anterior uveitis was associated with posterior uveitis. Visual acuity in all cases prior to treatment was 0.3 ± 0.21 and increased to 0.55 ± 0.29 after treatment. The mean gestational age of the patients was 19.76 ± 8.71 weeks at the time of hospital admission. No case of toxoplasmic ocular involvement was identified in the infants on postnatal examination. In the case of toxoplasma retinochoroiditis during pregnancy, appropriate treatment and follow-up is very important to protect the newborns and to prevent impaired vision in mothers.

Retina ganglion cell/inner plexiform layer and peripapillary nerve fiber layer thickness in patients with acromegaly.

Increased secretion of growth hormone and insulin-like growth factor-1 in acromegaly has various effects on multiple organs. However, the ocular effects of acromegaly have yet to be investigated in detail. The aim of the present study was to compare retina ganglion cell/inner plexiform layer (GCIPL) and peripapillary nerve fiber layer thickness (pRNFL) between patients with acromegaly and healthy control subjects using spectral domain optical coherence tomography (SD-OCT). This cross-sectional, comparative study included 18 patients with acromegaly and 20 control subjects. All participants underwent SD-OCT to measure pRNFL (in the seven peripapillary areas), GCIPL (in the nine ETDRS areas), and central macular thickness (CMT). Visual field (VF) examinations were performed using a Humphrey field analyzer in acromegalic patients. Measurements were compared between patients with acromegaly and control subjects. A total of 33 eyes of 18 patients with acromegaly and 40 eyes of 20 control subjects met the inclusion criteria of the present study. The overall calculated average pRNFL thickness was significantly lower in patients with acromegaly than in control subjects (P = 0.01), with pRNFL thickness significantly lower in the temporal superior and temporal inferior quadrants. Contrary to our expectations, pRNFL thickness in the nasal quadrant was similar between acromegalic and control subjects. The mean overall pRNFL thickness and superonasal, nasal, inferonasal, and inferotemporal quadrant pRNFL thicknesses were found to correlate with the mean deviation (MD) according to Spearman's correlation. However, other quadrants were not correlated with VF sensitivity. No significant difference in CMT values was observed (P = 0.6). GCIPL thickness was significantly lower in all quadrants of the inner and outer macula, except for central and inferior outer quadrants, in the acromegaly group than that in the control group (P < 0.05). GCIPL thicknesses of the inferior inner and outer macula quadrants were found to correlate with MD, whereas no correlation was observed between other quadrants and VF sensitivity. We demonstrated that GCIPL thickness decreased in patients with acromegaly compared with that in control subjects. However, the nasal quadrant pRNFL thickness was similar in acromegaly, in contrast to our expectations. SD-OCT may have utility in the assessment of the effects of acromegaly on retinal structures.

Serum Cytokine Levels in Behçet's Disease.

BACKGROUND: The aim of this study is to investigate and compare the serum levels of various cytokines in patients with Behçet's Disease and healthy controls. METHODS: Thirty-five patients with Behçet's disease and 29 age and sex-matched healthy controls were included in the study. The patients were separated into groups with active and inactive disease. Serum IL-2, IL-6, IL-8, IL-10, IL-17A, and IFN-γ levels were determined using the enzyme-linked immunosorbent assay method. Cytokine levels of the two patient groups and healthy controls were compared using SPSS 15.0. RESULTS: Ten patients with active disease and 25 patients with inactive disease were present. Serum IL-8 levels of active BD patients were higher compared to inactive patients (P = 0.048) and healthy controls (P = 0.02). IL-8 levels were correlated with the duration of symptoms (r = 0.490, P = 0.003) and time passed since diagnosis (r = 0.579, P ˂ 0.001). CONCLUSION: Behçet's disease involves complex interactions of cells of the immune system, mainly T lymphocytes and neutrophils. Further studies on the cytokine profile in Behçet's disease will aid in elucidation of its pathogenesis.

Anterior segment parameters of rabbits with rotating Scheimpflug camera.

BACKGROUND: Rabbit is one of the most commonly used experimental animals for corneal studies due to similarity of size to human cornea and ease of manipulation. In this study, we assessed anterior segment parameters of the healthy rabbit eyes with Pentacam HR (Oculus, Wetzlar, Germany). METHODS: Six-month-old, approximately 2.5-3 kg weighted, 30 female New Zealand rabbits were used in the study. Right eye of the each rabbit was imaged with Pentacam HR under intramuscular ketamine hydrochloride (Ketalar; Eczacibasi, Turkey) anesthesia (50 mg/kg). After the imaging, the rabbits with blinking errors, which results in low-quality images, were excluded from the study. Keratometric readings, central corneal thickness (CCT), anterior chamber depth (ACD), and anterior and posterior elevation values, and lens density were noted. RESULTS: In this study, the flattest and the steepest keratometric values were found as 43.34 ± 1.86, 42.7 ± 2.0, and 43.9 ± 1.9 diopters, respectively. The mean CCT and ACD of rabbits were found as 388 ± 39 µm and 2.08 ± 0.16 mm, respectively. Mean of the anterior and posterior elevation at thinnest point was found as 1.29 ± 4.28 and 3.91 ± 6.17 µm, respectively. CONCLUSIONS: Keratometric readings and anterior and posterior elevation values of rabbits were similar to human; however, corneal thickness and anterior chamber depth (ACD) values were lower than humans.

Prognostic factors for stereopsis in refractive accommodative esotropia.

OBJECTIVE: To determine the prognostic factors affecting stereoacuity in patients with refractive accommodative esotropia (RAE) according to the results of long follow- up period. METHODS: We reviewed the charts of 70 patients with RAE between the years 1985-2014. Patients were classified into three groups. G-1: Stereoacuity score 40 second/arc. G-2: Stereoacuity score >40 second/arc (50-3000). G-3: No binocular vision. Initiation age of RAE, duration of deviation, refractive error, amblyopia, amblyopia treatment, anisometropia, visual acuity, family history, angle of deviation for distance and near at each group and the prognostic factors affecting stereoacuity were analyzed. RESULTS: The mean initiation age of RAE was 2.7±1.5 years, the mean age at first visit was 6.4±4.2 years. The mean follow up time was 7.3±4.4 years. Seven patients had 40 second/arc, 48 patients had 50 to 3000 second/arc stereoacuity, 15 patients had no binocular vision. Mean deviation for near was statistically higher in group 2 and 3. Visual acuity levels were higher in group 1 and 2 and was statistically significant. Low visual acuity (p=0.001, 0.008), higher angle of deviation at near (p=0.01), increased duration of deviation (p=0.01), presence of amblyopia (p=0.001) and irregularity of amblyopia treatment (p=0.01) were significantly related with poor stereoacuity. CONCLUSION: According to the prognostic factors low stereoacuity was mostly related with amblyopia as a result the late presentation of the patients in seeking care. Appropriate treatment as full refractive correction and amblyopia treatment during the RAE is important for development of good stereopsis. Also angle of deviation at near and duration of deviation can be a useful predictor for poor stereoacuity levels.

Comparison of accelerated and conventional corneal collagen cross-linking for progressive keratoconus.

PURPOSE: To compare outcomes of accelerated and conventional corneal cross-linking (CXL) for progressive keratoconus (KC). MATERIALS AND METHODS: Patients were divided into two groups as the accelerated CXL group and the conventional CXL group. The uncorrected distant visual acuity (UDVA), corrected distant visual acuity (CDVA), refraction and keratometric values were measured preoperatively and postoperatively. The data of the two groups were compared statistically. RESULTS: The mean UDVA and CDVA were better at the six month postoperative when compared with preoperative values in two groups. While change in UDVA and CDVA was statistically significant in the accelerated CXL group (p = 0.035 and p = 0.047, respectively), it did not reach statistical significance in the conventional CXL group (p = 0.184 and p = 0.113, respectively). The decrease in the mean corneal power (Km) and maximum keratometric value (Kmax) were statistically significant in both groups (p = 0.012 and 0.046, respectively in the accelerated CXL group, p = 0.012 and 0.041, respectively, in the conventional CXL group). There was no statistically significant difference in visual and refractive results between the two groups (p > 0.05). CONCLUSIONS: Refractive and visual results of the accelerated CXL method and the conventional CXL method for the treatment of KC in short time period were similar. The accelerated CXL method faster and provide high throughput of the patients.

Ocular Blood Flow Changes in Behçet Disease Patients with/without Thrombotic Disease.

In this study, the authors aimed to evaluate ocular blood flow changes in Behçet disease (BD) with and without thrombotic disease. Ninety eyes of 90 patients with a diagnosis of BD (30 eyes with active uveitis, 23 eyes with inactive uveitis, 25 eyes without ocular involvement, and 12 eyes without ocular involvement and with a history of thrombosis) and 30 eyes of 30 age- and sex-matched control patients without any systemic disease with a total of 120 eyes were evaluated. In all cases, ophthalmic, central retinal, and ciliary artery flow parameters were measured with colour Doppler ultrasonography (CDU). The ocular blood flow parameters of all vessels in patients with active uveitis were found to be affected. All the flow parameters in the CRAs of the study groups were significantly different from the control group (p < 0.001). Additionally, in non-ocular BD patients with thrombosis, blood flow parameters were affected more than the parameters in non-ocular BD patients without thrombosis and control patients. In conclusion, major haemodynamic changes were observed using CDU in the ophthalmic vessels of ocular Behçet patients. Also, CDU may detect ocular blood flow alterations before initial ocular clinical manifestations appear in BD patients.

Mean platelet volume in ocular Behçet's disease.

OBJECTIVE: To determine whether mean platelet volume (MPV) is an indicator of disease severity in ocular Behçet's Disease (BD). MATERIALS AND METHODS: The study population was 30 newly diagnosed ocular BD patients who presented with active uveitis. These patients had no past history of smoking, drug use, or systemic diseases including diabetes mellitus, hypertension, cardiovascular disease, and renal disease. A control group consisting of 34 healthy individuals was included for comparison. MPV measurements were performed serially upon presentation with active uveitis and at one and three month thereafter in BD group whereas only at presentation in the controls. RESULTS: Upon presentation with active uveitis, the mean MPV levels were 7.88 ± 1.14 femtoliters (fL) for BD group. During the posttreatment follow-up period at first and third months, BD patients demonstrated a mean MPV level of 7.71 ± 1.12 fL and 7.65 ± 1.04 fL, respectively. The mean MPV value of control group, was 8.39 ± 0.66 fL at presentation. Fluctuations in MPV values were not significant in the BD group, while there was a significant difference between the initial measurements of the BD and control groups. CONCLUSION: MPV measurement in ocular BD is not a predictive laboratory test to determine the clinical improvement in early stages following classical immunosuppressive treatment.

Comparison of different grinding procedures on the flexural strength of zirconia.

STATEMENT OF PROBLEM: The surface of zirconia ceramic is damaged during grinding, which may affect the mechanical properties of the material. PURPOSE: The purpose of this study was to compare the biaxial flexural strength of zirconia after different grinding procedures and to measure the temperature rise from grinding. MATERIAL AND METHODS: Forty disk-shaped zirconia specimens (15 × 1.2 mm) with a smaller disk in the center of each disk (1 × 3 mm) were divided into 4 groups (n=10). The specimens were ground with a high-speed handpiece and micromotor with 2 different grinding protocols, continual grinding and periodic grinding (10 seconds grinding with 10 seconds duration), until the smaller disk was removed. Control specimens without the center disk (n=10) were analyzed without grinding. The biaxial flexural strengths of the disks were determined in a universal testing machine at a crosshead speed of 0.5 mm/min. The fracture strength (MPa) was recorded, and the results were analyzed using a 1-way ANOVA, Tukey HSD test, Student's t test, and Pearson correlation test (α=05). RESULTS: All grinding procedures significantly decreased flexural strength (P<.01). The mean flexural strength of the high-speed handpiece groups was higher (815 MPa) than that of the micromotor groups (718 MPa). The temperature values obtained from micromotor grinding (127°C) were significantly higher than those from high-speed handpiece grinding (63°C) (P<.01). CONCLUSIONS: Grinding zirconia decreased flexural strength. Zirconia material ground with a high-speed handpiece run continually caused the least reduction in flexural strength.

In vitro comparison of fracture strength of experimental hollow and solid design zirconia dowels.

PURPOSE: The aim of this study was to evaluate the fracture strength of experimental hollow and solid design zirconia dowels. MATERIALS AND METHODS: Three types of dowels (fiber-reinforced composite [FRC], hollow design, and solid design zirconia dowels) were tested in the study (n = 10). A three-point bending method was conducted, and a load was applied until fracture. The values were recorded as Newtons (N) and then converted to megapascals (MPa) according to the diameter of the dowels. Statistical analyses were performed using one-way ANOVA and Tukey HSD tests. The significance was set at p < 0.05. RESULTS: The mean fracture strength of the hollow design zirconia dowels was significantly higher (960.72 MPa) than solid zirconia dowels (741.78 MPa) and FRC dowels (687.64 MPa) (p < 0.05). CONCLUSIONS: The hollow design zirconia dowel seems to have sufficient fracture strength for anterior restorations. This design may be beneficial to access the apical region when retreatment is necessary, without any dowel-removing procedure.

A Rare Orbital Pathology: A Large Orbital Dermatofibrosarcoma Protuberans.

Dermatofibrosarcoma protuberans (DFSP) is a rare sarcoma of the dermis. It is a malignant, locally aggressive, and infiltrative tumor with frequent recurrence. In this case, a 44-year-old woman presented with a 15-year history of a swelling in the medial canthus of the right eye that caused tearing. Imaging revealed a septated mass isodense to soft tissue that had eroded the medial wall of the orbit. Macroscopic examination showed an elastic, gray-brown, encapsulated, irregular mass measuring 45x35x22 mm. The surgical margins were positive, so adjuvant radiotherapy was started. The patient was followed for 2 years without recurrence. According to the literature, this mass is the largest orbital DFSP treated by globe-sparing primary resection.

Clinical management of a fractured anterior tooth with reattachment technique: a case report with an 8-year follow up.

Fracture of anterior teeth is a relatively common outcome of trauma to the teeth. If the fractured teeth fragments are recovered by the patient and brought to the dental office within reasonable time, the fragments may be reattached to the remaining tooth structure. This article presents a case of a 15-year-old male patient with fractured left maxillary lateral incisor. The fragment reattachment was performed using dual-cured composite resin cement and the treatment outcomes of an 8-year follow up were presented. The technique described in this case report for reattachment of the fractured fragments is simple, while restoring providing long-lasting esthetics and improved function with a very conservative approach.

Zirconia dental implants: a literature review.

Titanium and titanium alloys are widely used for fabrication of dental implants. Because of potential immunologic and possible esthetic compromises with titanium implants, novel implant technologies are being developed. However, these novel technologies must maintain the characteristics that provide titanium implants with their high success rates. Zirconia implants were introduced into dental implantology as an alternative to titanium implants. Zirconia seems to be a suitable implant material because of its toothlike color, mechanical properties, biocompatibility, and low plaque affinity. The aim of this study is to review clinical and research articles conducted on zirconia dental implants, compare them with titanium dental implants, and provide information on zirconia dental implant osseointegration and mechanical strength. Zirconia dental implants have the potential to become alternative dental implants to titanium dental implants, but they are not yet in routine clinical use.

Zirconia ceramic post systems: a literature review and a case report.

Cast metal post-core systems have a long history of successful use because of their superior physical properties. However, their high elastic modulus can cause stress concentrations within the surrounding radicular dentin, resulting in root fractures. Moreover, the increasing demand for more esthetically appealing and biocompatible restorations has led to the development of tooth-colored, translucent, metal-free post-core systems. Notably, prefabricated zirconia ceramic post systems have been introduced to satisfy this trend toward a heightened awareness of esthetics, whereby the translucency of all-ceramic crowns can be successfully maintained with the use of ceramic post-core materials. Owing to the keen interest in and widespread use of zirconia ceramic post systems, many in vitro studies on zirconia posts have been published in the last 15 years. The aim of this article was to present data about the retention, fracture resistance, microleakage, light transmission, esthetic advantages, and radiodensity of zirconia posts. Two clinical survival rate studies were also presented. Based on the results of these studies, zirconia posts have been shown to improve the esthetic quality of all ceramic crowns and thus their usage is recommended. Apart from literature review, a case report in which a fractured fiber post was replaced with a custom-made zirconia post was also presented.

In vitro evaluation of shear bond strength of veneering ceramics to zirconia.

The bond strength between veneering ceramic and zirconia framework is the weakest link in the layered structure. To investigate the shear bond strength (SBS) of veneering ceramics to zirconia, four types of zirconia ceramics (Zirkonzahn, Cercon, Lava, DC-Zirkon) were selected. For each zirconia system, 30 disk specimens were layered with IPS e.max Ceram, Vita VM9, and a manufacturer-recommended veneering ceramic. SBS test was conducted, and fracture surface analysis was also performed to determine the failure modes. One-way ANOVA, two-way ANOVA, and Tukey's HSD tests were used to analyze the data. On shear bond strength between zirconia and their recommended veneering ceramics, statistically significant differences were observed among the different zirconia systems (p<0.001). DC-Zirkon exhibited the highest SBS value (40.49+/-8.43 MPa), followed by Lava (27.11+/-2.72 MPa), Zirkonzahn (24.46+/-3.72 MPa), and Cercon (20.19+/-5.12 MPa). On shear bond strength to IPS e.max Ceram and Vita VM9, significantly lower (p<0.001) were observed for these veneering ceramics than their recommended veneering ceramics for DC-Zirkon and Lava. For Zirkonzahn and Cercon, similar SBS values were observed for all kinds of veneering ceramics (p>0.05). In conclusion, the bonding of manufacturer-recommended veneering ceramic to the zirconia framework differed according to zirconia type.

Clinical success of zirconia in dental applications.

The application of ceramic materials for the fabrication of dental restorations is a focus of interest in esthetic dentistry. The ceramic materials of choice are glass ceramics, spinel, alumina, and zirconia. Zirconia was introduced into dentistry in the 1990s because of its good mechanical and chemical properties and is currently being used as a material for frameworks, dowels, implants, abutments, and orthodontic brackets. Many in vitro studies about zirconia use have been published, but clinical long-term studies are very important. This article presents data regarding the incidence of clinical success and complications of zirconia in these dental applications. Clinical studies published to date seem to indicate that zirconia is well tolerated and sufficiently resistant.

Automated quantification of foveal avascular zone and vascular density in Behçet's disease.

PURPOSE: To measure the vascular density (VD) and foveal avascular zone (FAZ) area in patients with Behçet's disease (BD) obtained by optical coherence tomography angiography (OCTA). METHODS: VD and FAZ area in the deep and superficial retinal vascular networks were measured in all eyes. RESULTS: Thirty BD and 31 control subjects were included in the study. The mean overall VD measured in the entire scan was lower in BD compared with control group in both the superficial (49.52 ± 6.54 vs 53.57 ± 2.87%, respectively; p = 0.003) and deep (53.44 ± 7.44 vs 58.41 ± 3.01%, respectively; p = 0.002) areas. The FAZ in the BD group was significantly increased at the level of the superficial (0.52 ± 0.67 vs 0.28 ± 0.1 mm2, respectively; p = 0.05) and deep (0.91 ± 1.25 vs 0.39 ± 0.14 mm2, respectively; p = 0.024) areas compared with those of the control group. The deep and the superficial FAZ areas were positively correlated with disease duration and negatively with VA. CONCLUSION: In the patients with BD, OCTA showed decreased VD in both the superficial and deep retinal vascular networks. Besides, the VA was correlated with the VD and FAZ.