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.

Clinical characteristics, histopathology, and treatment outcomes in adult and pediatric patients with nonspecific orbital inflammation.

PURPOSE: To evaluate the clinical characteristics, histopathology, and treatment outcomes in adult and pediatric patients with nonspecific orbital inflammation (NSOI). METHODS: This retrospective study evaluates 76 patients with NSOI. The patients were categorized in 9 groups according to the site of involvement and histopathology results. These groups included: anterior involvement, dacryoadenitis, myositis, perineural involvement, acute fat involvement, focal mass, orbital apex involvement, diffuse sclerosing form, and multiple tissue involvement. The course of the disease was categorized as acute, subacute, or chronic. The cases with symptom duration of less than 1 week were classified as acute, 1 week to 1 month as subacute, and more than 1 month as chronic. RESULTS: 36 (47.4%) patients were males. The mean age was 41.68 ± 17.62 (6-75) years. The most common signs and symptoms were periorbital pain, periorbital edema, decreased ocular movements or diplopia, and conjunctival injection. The most common group was dacryoadenitis in 29 (38.1%) cases. The most common form of disease was the acute involvement (50% of patients). Most of the patients were treated by oral corticosteroids. Duration of follow-up was 7.17 ± 6.26 months. Recurrence occurred in 9 (11.8%) of patients during the follow-up period. CONCLUSIONS: This study presents a new categorization in which multiple tissue involvements were separated. Some of the NSOI features differ between adults and children. In most patients, treatment especially with corticosteroids, resolves the clinical findings.

Lateral rectus muscle recession and the vertical palpebral fissure height: to do or not to do inter-muscular septum dissection?

In this study, we aimed to evaluate changes of vertical palpebral fissure height (VPFH) after unilateral lateral rectus muscle recession. Twenty-five and twenty-six patients who were candidates for lateral rectus muscle recession were assigned into "with" and "without" intermuscular septum dissection study arms. The VPFH was measured at one-day before surgery and in two weeks and three months, postoperatively. Three months after surgery, significant increase of VPFH was observed in both groups (Paired t-test; P=0.005). Also, less widening of VPFH was observed in "with intermuscular septum dissection" group (Change in VPFH in "with intermuscular septum dissection" vs "without intermuscular septum dissection" groups: 0.48 mm vs 1.34 mm; ANCOVA test; P<0.001). However, such results were not observed two weeks post-operatively (Change in VPFH in "with intermuscular septum dissection" vs "without intermuscular septum dissection" groups: -0.28 mm vs 0.28 mm; ANCOVA test; P=0.302). Intermuscular septum dissection is recommended in lateral rectus muscle recession to partially prevent the undesirable increment of VPFH.

Orbital invasion of ameloblastoma: A systematic review apropos of a rare entity.

PURPOSE: Ameloblastoma is a non-encapsulated and slow-growing tumor with high recurrence rate. Orbital involvement by this neoplasm is an extremely rare entity. In this study, we present a systematic review on this situation along with clinical and paraclinical features of a case. METHODS: An electronic search was conducted on major medical sources. Data of the cases in the literature in addition to our own case were extracted, summarized, and statistically analyzed. RESULTS: A total of 36 other cases from 20 relevant studies were also reviewed. Review topics included epidemiology, clinical presentation, pathologic features, differential diagnosis, imaging, treatment, and prognosis. We provided a five-year history of a 50-year-old man with orbital/skull base invasion of plexiform maxillary ameloblastoma. CONCLUSIONS: Maxillary ameloblastoma is a locally aggressive neoplasm, and physicians must be alert to the biologic behavior of this tumor to detect any invasion to critical structures such as orbit and cranium. Orbital ameloblastoma causes significant morbidity and mortality. We advocate meticulous patient follow-up with regular clinical examinations and paraclinical work-up for timely detection of any invasion or recurrence. The best must be done to avoid extensions by aggressive removal of maxillary ameloblastoma.

The effects of smoking on corneal endothelial cells: a cross-sectional study on a population from Isfahan, Iran.

PURPOSE: The aim of this study is to compare the effect of smoking in corneal endothelial cell number and morphology by specular microscopy on a non-smoker population. METHODS: Our cross-sectional study was performed on 150 participants from a non-smoker population. Non-contact specular microscopy (Tomey Corporation Inc., Nagoya, Japan) was performed in the center of the cornea of all subjects. The cell density (CD), average cell size (AVG), percent of hexagonality (HEX%) and central corneal thickness (CCT) were calculated and compared in both groups. RESULTS: Totally, 76 eyes of 76 smokers and 74 eyes of 74 non-smokers were enrolled in the study from 2015 to 2016. The mean age of smokers and non-smokers were 48.61 ± 17.04 and 46.39 ± 13.02, respectively. The mean number of pack/year among the smokers was 17.36 ± 14.68. Also, the mean values of AVG and CD were significantly different for these two groups (p = 0.011 and p = 0.039, respectively). Other corneal endothelial variables did not show a significant difference between smokers and non-smokers (p > 0.05). However, smokers with severe nicotine dependency had significantly greater AVG and lower CD in comparison with the non-smokers (p = 0.004 and p = 0.013, respectively). CONCLUSION: Our study showed that smoking can cause significant changes in some of the corneal endothelial variables, but not all of them.

Femtosecond laser arcuate keratotomy for the correction of postkeratoplasty high astigmatism in keratoconus.

BACKGROUND: Astigmatism is the leading complication in visual recovery after penetrating keratoplasty (PKP) and deep anterior lamellar keratoplasty (DALK); in this study, we evaluated the outcome of femtosecond laser arcuate keratotomy (FLAK) after DALK and PKP in Iranian keratoconic patients. MATERIALS AND METHODS: In this prospective interventional case series, refractive and keratometric predictability, efficacy, and complications of FLAK for postkeratoplasty astigmatism in keratoconus were evaluated; 23 eyes of 23 consecutive patients (mean age of 32.43 ± 9.11 years) with high astigmatism were enrolled. The femtosecond laser performed paired 90°-angled arcuate incisions. RESULTS: Mean logarithm of the minimum angle of resolution of corrected and uncorrected visual acuity improved from preoperative values of 0.30 ± 0.18 and 0.85 ± 0.32 to 6-month values of 0.19 ± 0.17 and 0.65 ± 0.33, respectively (P < 0.05). Mean subjective astigmatism was 7.79 ± 2.64 diopter (D) preoperatively and 3.69 ± 2.25D at 6-month after surgery (P < 0.05). Surgically induced astigmatism was 9.27 ± 5.00D. Mean refractive spherical equivalent showed no significant (P = 0.69) hyperopic shift from - 4.21 ± 4.84D preoperatively to - 2.16 ± 6.09D postoperatively. Two (8.7%) microperforations were observed. CONCLUSION: FLAK is a relatively safe and effective method for the treatment of postkeratoplasty astigmatism.

Presentation of massive orbital hidrocystoma at birth: case report and review of the literature.

BACKGROUND: Hidrocystoma, or sudoriferous cyst, is an eyelid tumor originating from apocrine or eccrine sweat glands. Its presence in the orbit is relatively rare. CASE PRESENTATION: A full-term female child with severe right eye extrusion was referred to our department two hours after birth. We performed cyst aspiration under ultrasonic guidance; 15 cc straw-colored fluid was obtained and proptosis resolved significantly. Orbital magnetic resonance imaging (MRI) showed a large unilocular retrobulbar mass with hypo-intensity in T1 and hyper-intensity in T2. The case underwent further daily ocular assessment until day 5; when proptosis began to worsen again. On day 6, under general anesthesia, we performed aspiration and then the cyst was completely removed with an intact wall through a trans-conjunctival incision. The diameter of the aspirated cyst was about 4 cm. In pathologic consultation, a cystic cavity lined by a layer of sweat duct like epithelium with apical snouts consistent with the diagnosis of apocrine hidrocystoma was reported. CONCLUSION: To date, in the literature, six other cases of orbital hidrocystoma have been reported in childhood with protean clinical pictures; none of which presented at birth. Herein, we introduce the first case report at birth and also provide a review on the literature. Our report strongly argues against the well reputed theory of traumatic origin for orbital hidrocystoma; it has been postulated that this tumor may be the result of sweat gland cells implantation through the orbit. We thereby suggest the possible presence of choristomatous ectopic sweat gland cells in the orbit during embryogenesis.

Comparison of Scheimpflug and swept-source anterior segment optical coherence tomography in normal and keratoconus eyes.

PURPOSE: The purpose of the study was to assess the agreement of anterior segment optical coherence tomography with its older well-known opponent i.e., Sheimpflug imaging in evaluation of the cornea in normal and keratoconus subjects. METHODS: 107 normal and 56 keratoconus eyes were evaluated with the anterior segment optical coherence tomography followed by the Scheimpflug imaging. Parameters included axial keratometry data in both of steep and flat meridians, mean keratometry and the astigmatism values in the central 4.0 mm zone, central, thinnest and apex corneal thicknesses, Q-value in 8 mm zone and pupil diameter. Corneal topographic maps were recorded and were evaluated for anterior highest and lowest points, posterior highest and lowest points. Average values were recorded for analysis. RESULTS: All anterior cornea keratometry indices showed perfect agreement between two devices in normal corneas; while the level of agreement in keratoconus cases ranged from moderate to strong. All posterior keratometry indices also showed perfect agreement in both groups; except for flat K in normal corneas and steep K in KC ones. The amount of corneal cylinder in normal corneas had perfect agreement, and moderate to strong agreement in anterior/posterior cornea in keratoconus group. Anterior highest and lowest points showed strong and perfect agreement in normal and keratoconus cases, respectively. Posterior highest and lowest points showed strong agreement in normal cases. Thickness indices (central, thinnest, and apex thicknesses) showed perfect agreement between two devices in both normal and KC groups. Mean values of anterior and posterior highest points were statistically higher in Scheimpflug system. CONCLUSIONS: Although two imaging technologies had statistically numerical different output, it seems that they have a good agreement in most parameters.

Intravitreal Diclofenac plus Bevacizumab versus Bevacizumab alone in treatment-naive diabetic macular edema: a randomized double-blind clinical trial.

The aim of this study is to evaluate the short-term effects of a single intravitreal injection of 1.25 mg Bevacizumab combined with 300 lg/0.1 mL Diclofenac (IVB/D) versus 1.25 mg intravitreal Bevacizumab (IVB) alone in the treatment of naive diabetic macular edema (DME). In this prospective, randomized clinical trial, 80 eyes were included in the final analysis; 42 and 38 of which in the IVB and IVB/D groups, respectively. The primary outcome measure was a change in best-corrected visual acuity (BCVA) in logMAR at week 4. The secondary outcomes included changes in central macular thickness (CMT), macular volume, and potential injection-related complications. Significant improvement of BCVA was demonstrated in both study arms (mean reductions in LogMAR: -0.088 ± 0.278, -0.228 ± 0.330 for IVB and IVB/D, respectively). The difference in BCVA changes was in favor of IVB/D; however, not to a statistically significant level (P = 0.160). Significant reduction of CMT was documented in both study arms (mean reductions: 82.43 ± 160.09 and 153.26 ± 163.85 for IVB and IVB + IVD, respectively). Comparison of CMT changes between groups showed that IVB/D reduced CMT more than that of IVB (P = 0.04). Effects on macular volume corresponded to those of CMT. No injection-related complications or significant alterations in intraocular pressure were observed in any of the study arms. In treatment-naive DME, superiority of IVB/D combination therapy over IVB monotherapy may exist; especially as regards anatomical features. In our therapeutic arsenal for DME, IVD can be added as an adjunct to Bevacizumab.

Effects of Corneal Collagen Crosslinking on Confocal Microscopic Findings and Tear Indices in Patients with Progressive Keratoconus.

BACKGROUND: To evaluate any change in tear indices and confocal microscopic findings after corneal collagen crosslinking (CXL) in patients with progressive keratoconus. METHODS: Thirty-two consecutive eyes from 23 patients having progressive keratoconus were enrolled in this prospective, interventional cohort study. The standard crosslinking surgery was performed for all patients. Visual, refractive, and topographic evaluations were done before and at 6 months after surgery. Tear function tests and confocal microscopic examination were performed before and at 1 month and 6 months after the procedure. RESULTS: There was no significant change in Schirmer-1 test results and tear osmolarity at 1 month and 6 months after CXL. Using confocal microscopy, all eyes showed reduced or absent subepithelial nerve plexus. Differences in basal epithelial cell density, epithelial mean cell area, and keratocyte density in anterior and middle stroma and endothelial cell pleomorphism were all significant at 1 month and 6 months after CXL (P < 0.05). No significant change was noted in endothelial cell count and their polymegathism at 6 months follow-up. Significant improvement was noted in uncorrected visual acuity, best corrected visual acuity, flattest corneal meridian (K2), and maximum keratometry in Pentacam (Kmax) after 6 months of the procedure. CONCLUSIONS: While CXL would have no effect on tear indices and endothelial cell count, it can cause a significant reduction in subepithelial nerve plexus and significant alterations in epithelial cell density in the anterior and middle stroma.

Preoperative Topical Diclofenac and Ketorolac in Prevention of Pain and Discomfort Following Photorefractive Keratectomy: A Randomized Double-masked Placebo-controlled Clinical Trial.

OBJECTIVES: To compare the efficacy of a single dose of topical diclofenac 0.1% and ketorolac 0.5%, with placebo and with each other in the prevention of post-PRK pain and discomfort. METHODS: In this randomized double-masked trial, adults undergoing bilateral PRK surgery were assigned to two arms. The first arm received a single dose diclofenac 0.1%, randomly in either the right, or left eye, and artificial tear (as the placebo) in the other eye. The second arm received ketorolac 0.5%, by the same pattern. The primary outcome of this study was ocular[1] pain assessed by visual analogue scale (VAS), and,[2] discomfort including itching, foreign body sensation, tearing and photophobia which were questioned in 4 degrees. RESULTS: In the final analysis, 47 and 36 subjects remained in the diclofenac and ketorolac treated arms, respectively. In both arms, on the first and second post-operation days, VAS scores were significantly lower in the pretreated eye. Moreover, on the first post-operation day, the intensity of all ocular discomfort items was statistically lower in the pretreated eyes; whereas, on the second day, such a difference was only observed for foreign body sensation and itching in the diclofenac treated arm and for photophobia in ketorolac treated arm. Comparison of the two arms (diclofenac pretreated eyes vs. ketorolac pretreated eyes) on both first and second post-operation days showed no significant difference neither in the VAS scores nor the ocular discomfort items. CONCLUSIONS: Either diclofenac or ketorolac instilled at a dose of one drop 30 minutes in advance of the operation would be equally beneficial in the short-term prevention of post-PRK pain and discomfort.

Management of corneal bee sting.

Corneal bee sting is an uncommon environmental eye injury that can result in various ocular complications with an etiology of penetrating, immunologic, and toxic effects of the stinger and its injected venom. In this study we present our experience in the management of a middle-aged male with a right-sided deep corneal bee sting. On arrival, the patient was complaining of severe pain, blurry vision with acuity of 160/200, and tearing, which he had experienced soon after the injury. Firstly, we administered conventional drugs for eye injuries, including topical antibiotic, corticosteroid, and cycloplegic agents. After 2 days, corneal stromal infiltration and edema developed around the site of the sting, and visual acuity decreased to 100/200. These conditions led us to remove the stinger surgically. Within 25 days of follow-up, the corneal infiltration decreased gradually, and visual acuity improved to 180/200. We suggest a two-stage management approach for cases of corneal sting. For the first stage, if the stinger is readily accessible or primary dramatic reactions, including infiltration, especially on the visual axis, exist, manual or surgical removal would be indicated. Otherwise, we recommend conventional treatments for eye injuries. Given this situation, patients should be closely monitored for detection of any worsening. If the condition does not resolve or even deteriorates, for the second stage, surgical removal of the stinger under local or generalized anesthesia is indicated.