Corneal Epithelial Thickness Mapping: A Major Review.

The corneal epithelium (CE) is the outermost layer of the cornea with constant turnover, relative stability, remarkable plasticity, and compensatory properties to mask alterations in the underlying stroma. The advent of quantitative imaging modalities capable of producing epithelial thickness mapping (ETM) has made it possible to characterize better the different patterns of epithelial remodeling. In this comprehensive synthesis, we reviewed all available data on ETM with different methods, including very high-frequency ultrasound (VHF-US) and spectral-domain optical coherence tomography (SD-OCT) in normal individuals, corneal or systemic diseases, and corneal surgical scenarios. We excluded OCT studies that manually measured the corneal epithelial thickness (CET) (e.g., by digital calipers) or the CE (e.g., by confocal scanning or handheld pachymeters). A comparison of different CET measuring technologies and devices capable of producing thickness maps is provided. Normative data on CET and the possible effects of gender, aging, diurnal changes, refraction, and intraocular pressure are discussed. We also reviewed ETM data in several corneal disorders, including keratoconus, corneal dystrophies, recurrent epithelial erosion, herpes keratitis, keratoplasty, bullous keratopathy, carcinoma in situ, pterygium, and limbal stem cell deficiency. The available data on the potential role of ETM in indicating refractive surgeries, planning the procedure, and assessing postoperative changes are reviewed. Alterations in ETM in systemic and ocular conditions such as eyelid abnormalities and dry eye disease and the effects of contact lenses, topical medications, and cataract surgery on the ETM profile are discussed.

In vivo application of decellularized rat colon and evaluation of the engineered scaffolds following 9 months of follow-up.

The aim of this study was to investigate the rat small intestine mesentery and colon as natural bio-reactors for rat colon-derived scaffolds. We decellularized eight whole rat colons by a perfusion-based protocol using 0.1% sodium dodecyl sulfate for 24 hr. The provided bio-scaffolds were examined by histological staining, scanning electron microscopy, and collagen and sulfated glycosaminoglycan quantification. Subsequently, we implanted 4 cm segments of the provided bio-scaffolds into two groups of animal models comprising tissue grafting into the mesenteric tissue (n: 10) and end-to-end anastomosis (n: 10) to the colon of host rats. Following 9 months of follow-up, we harvested the grafts and performed histological and immunohistochemical studies as well as real-time PCR evaluation for telomerase activity of the samples. Histological staining, scanning electron microscopy and protein content evaluation of the acellular tissues confirmed the complete removal of the cellular components and preservation of the extracellular matrix. Histopathological assessment of the implanted scaffolds was suggestive of a regenerative process in both groups. Moreover, immunohistochemical analysis of the samples confirmed the presence of smooth muscle cells, endothelial progenitor cells, and neural elements in both groups of grafted scaffolds. Our data confirmed the recellularization of the acellular colon grafts in both groups after 9 months of follow up. Also, the implanted tissues demonstrated different characteristics based on their implantation location. The outcomes of this investigation illustrate the capability of acellular tissues for in vivo application and regeneration.

Pachydermoperiostosis: A clinicopathological description.

PURPOSE: To report a case of pachydermoperiostosis (PDP) and a review of the literature. METHODS: A 32-year-old man was referred to our clinic with bilateral eyelid swelling and blepharoptosis. On examination, marked blepharoptosis was noted, and his eyelids were found to be floppy. Systemic examination was significant for clubbing of digits, coarse acromegalic facial features, and furrowing and oiliness of the skin of scalp and forehead. RESULTS: The patient was diagnosed as a case of PDP. On the brain MRI, the pituitary gland was enlarged, and the border of clivus was irregular. Pituitary and thyroid hormone levels were normal. He underwent bilateral lateral tarsal strip (LTS) procedure to address the eyelid laxity. Histopathologic examination revealed marked sebaceous gland hyperplasia with mucin deposition in the dermis. CONCLUSION: Floppy eyelid syndrome, clubbing, and acromegaloid face are main features that could lead to the diagnosis of PDP.

Cystoid macular edema with prostaglandin analogue use after uneventful cataract surgery in glaucoma patients.

PURPOSE: To evaluate the effect of postoperative latanoprost administration on central macular thickness (CMT) after uneventful cataract surgery in glaucoma patients. SETTING: Farabi Eye Hospital, Tehran, Iran. DESIGN: Prospective randomized clinical trial. METHODS: In this single-masked trial, glaucoma patients treated with latanoprost who had no other risk factor for the development of pseudophakic macular edema were randomly allocated to continuation of latanoprost or discontinuation of the drop after uneventful cataract surgery. At baseline and postoperatively at 1 month and 3 months, patients had complete ocular examinations and CMT measurements using optical coherence tomography. The main outcome measure was the change in the CMT between baseline measurements and postoperative measurements at 1 month and 3 months. RESULTS: One hundred fifty-six eyes (latanoprost 76; discontinuation 80) finished the trial. There were no differences in baseline patient demographics or characteristics, including the CMT, between the two groups. There was transient increase in the mean CMT by 12 µm ± 49 (SD) in the latanoprost group at 1 month (P = .03); however, the value returned to baseline by 3 months (6 ± 55 µm; P = .27). The between-group difference in the mean change in the CMT from baseline was -3.1 µm (95% confidence interval [CI], -18.4 to 12.0; P = .68) after 1 month and -10.5 µm (95% CI, -26.6 to 5.5; P = .19) after 3 months; the differences were not significant. CONCLUSION: Latanoprost administration after cataract surgery had no measurable effect on macular thickness.

Circulating mesenchymal stem cells, stromal derived factor (SDF)-1 and IP-10 levels increased in clinically active multiple sclerosis patients but not in clinically stable patients treated with beta interferon.

BACKGROUND: Mesenchymal stem cells (MSCs) have the capacity to migrate into the inflammatory regions in response to chemokines such as, IP-10 and SDF-1α and function as anti-inflammatory and immunomodulatory cells. METHODS: In this study we investigated the MSCs frequency in peripheral blood of Relapsing-Remitting Multiple Sclerosis (RRMS) patients in clinically active and not on disease-modifying therapy (DMT) (n = 22) and clinically stable on DMT (Interferon-ß (IFN-ß) therapy) for at least 6 months (n = 22) in comparison to sex and age-matched healthy controls (n = 25) using flow cytometry. The serum and gene expression levels of IP-10 and SDF-1a were also measured in studied groups by ELISA and Real time- PCR. RESULTS: We obtained significant high levels of circulating CD45-CD34- CD90+ and CD45-CD34- CD105+ cells in clinically active patients, not on DMT and patients under IFNß therapy compared with control group. Furthermore, a significant increase in the percentage of circulating CD45-CD34- CD105+ CD90+ cells was found in clinically active patients and not on DMT compared with control group. Serum analysis of IP-10 and SDF-1α showed a significant increase in IP10 concentration in both clinically active not on DMT (P = 0.02) and on DMT (P = 0.005) RRMS patients in comparison with controls. The expression level of SDF-1α mRNA significantly increased in clinically active not on DMT (P = 0.03), while decreased in patients under IFNß therapy (P = 0.04). The mRNA expression of IP-10 only increased in patients on DMT compared with controls (P = 0.05). CONCLUSION: Circulating MSCs, IP-10 and SDF-1α levels, increased in RRMS patients with clinically active not on DMT and IFN-ß therapy reduced circulating MSCs and SDF-1α levels.

Decellularised whole ovine testis as a potential bio-scaffold for tissue engineering.

The aim of this study was to determine an efficient whole-organ decellularisation protocol of a human-sized testis by perfusion through the testicular arteries. In the first step of this study, we determined the most efficient detergent agent, whereas the second phase delineated the optimal time required for the decellularisation process. Initially sheep testes were decellularised by one of three different detergent agents: sodium dodecyl sulphate (SDS), Triton X-100 and trypsin-ethylenediamine tetraacetic acid (EDTA) solutions, each perfused for 6h. In the second phase, the selected detergent agent was applied for different time periods. A total number of 20 organs were processed during this investigation. The efficacy of the decellularisation process and the preservation of the extracellular matrix components and structure were evaluated by histopathological examinations, 4',6'-diamidino-2-phenylindole (DAPI) staining, DNA quantification, hydroxyproline measurement, magnetic resonance imaging and scanning electron microscopy. Organ perfusion with 1% SDS solution for 6 to 8h demonstrated the most desirable outcomes regarding decellularisation and extracellular matrix preservation. The 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay was used to determine the toxicity of the scaffold and its potential for further application in tissue-engineering investigations. This investigation introduces an efficient method to produce a three-dimensional testicular bio-scaffold resembling the properties of the native organ that could be employed in tissue-engineering studies.

Fungal keratitis: An overview of clinical and laboratory aspects.

Mycotic keratitis or keratomycosis is a fungal infection with global distribution. The dominant aetiology of this disease varies based on geographical origin, socioeconomic status, and climatic condition. Generally, Aspergillus spp. and Fusarium spp. are common in tropical and subtropical regions and Candida spp. are dominant in temperate areas. Demonstration of fungal elements in microscopic examination besides the isolation of fungi in culture is the gold standard of laboratory diagnosis. As the culture is a time-consuming procedure, other approaches such as in vivo confocal microscopy which produces real-time imaging of corneal tissue and molecular techniques have been developed to facilitate rapid diagnosis of fungal keratitis. The first choice of treatment is topical natamycin, although topical amphotericin B is the best choice for Aspergillus and Candida keratitis. Regarding the diversity of fungal aetiology and the emergence of drug resistance in some genera and species, proper identification using molecular methods and antifungal susceptibility testing could provide useful data. Furthermore, as the better efficacy of combination therapy in comparison to monotherapy is reported, in vitro determination of interactions between various drugs seem informative. This review aims to provide a general and updated view on the aetiology, risk factors, epidemiology, clinical and laboratory diagnosis, and management of fungal keratitis.

A pilot randomized study on use of oral acetazolamide in patients with refractory dysuria.

PURPOSE: Assessment of daily oral acetazolamide in treatment of refractory dysuria. METHODS: Forty-one patients were randomly allocated to either be treated with acetazolamide (250 mg twice daily) or to receive placebo. The irritative voiding symptoms and urinary pH were recorded before and after treatment. The quality of life indices including the impact of voiding symptoms on daily and social activities, mood disturbance and sleep disorders were also measured by a questionnaire. RESULTS: Urinary pH was increased in the group taking acetazolamide (P < 0.001). They also reported alleviation of dysuria (P < 0.001), frequency (P = 0.039) and urgency (P = 0.016). However, nocturia was not improved in the study group. No change was observed in the aforementioned parameters in the placebo group. Daily personal life, social activities and the quality of sleep were improved by 52, 38 and 33%, respectively. CONCLUSION: Oral acetazolamide can reduce the irritative voiding symptoms and improve the quality of life which is concomitant with an increase in urinary pH.