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Purpose We report a case of incision failure during small incision lenticule extraction (SMILE) and its management. Observations The incision could not be made using the femtosecond laser because of a redundant conjunctiva, so it was instead done manually using a diamond knife. The lenticule was successfully separated and extracted. Three months after the procedure, the uncorrected distance visual acuity was 20/20 and no complication was observed. Conclusions and importance This case demonstrates that the conjunctiva should be carefully examined before SMILE. If a complication occurs because of conjunctivochalasis, it can be resolved with proper management without compromising the patient's visual acuity.

PURPOSE: To report a case of successful bilateral small incision lenticule extraction (SMILE) performed on a patient who had penetrating keratoplasty and astigmatic keratotomy in the right eye and penetrating keratoplasty in the left eye. METHODS: Case report. RESULTS: Astigmatic keratotomy was used to reduce astigmatism of the right eye because astigmatism was higher than the maximum correction limitation of SMILE. Bilateral SMILE was performed afterward. Although there were no difficulties during lenticule separation and removal of the right eye, wound dehiscence occurred during lenticule separation of the left eye. Two sutures were used at both ends of the incision, and the remainder of the procedure was successfully completed. Visual acuity improved to 20/50 in both eyes without correction, and the corrected distance visual acuities were 20/50 and 20/30 in the right and left eyes, respectively, at the 6-month postoperative visit. CONCLUSIONS: SMILE is a potentially effective alternative in correcting refractive errors in patients following penetrating keratoplasty. However, studies with a larger patient population with longer follow-up periods are needed to confirm these initial findings. [ J Refract Surg. 2016;32(9):644–647.]

PURPOSE To explore the clinical effects of combined full-thickness astigmatic keratotomy and small-incision lenticule extraction (SMILE) in patients who are inoperable using SMILE alone. METHODS We included 13 eyes of 9 patients with high-level or mixed astigmatism who underwent full-thickness astigmatic keratotomy followed by SMILE (secondarily) to correct the residual refractive error. RESULTS Six months after SMILE, the spherical equivalent was reduced from -4.83 ± 3.26 D to -0.17 ± 0.38 D (P < 0.001), and the astigmatism was reduced from 5.12 ± 0.96 D to 0.21 ± 0.22 D (P < 0.001). The uncorrected and corrected (CDVA) distance visual acuities improved from 1.07 ± 0.62 to 0.02 ± 0.13 (P < 0.001) and from 0.08 ± 0.14 to -0.01 ± 0.14 (P = 0.002), respectively. The CDVA improved by 1 or 2 Snellen lines in 8 cases (61.5%), and there was no loss in CDVA. All procedures were completed without intraoperative or postoperative complications. CONCLUSIONS This combined procedure was effective and safe for the treatment of high-level or mixed astigmatism.

We report a case of a 23-year-old woman with congenital nystagmus who had small-incision lenticule extraction (SMILE) procedure to correct refractive errors. The manifest refraction was -5.50 -1.75 × 180 in the right eye, -5.0 -2.50 × 180 in the left eye, and the patient presented with horizontal pendular nystagmus with an amplitude range of 5 to 10 degrees. Uneventful simultaneous bilateral small-incision lenticule extraction was performed. Six months postoperatively, the uncorrected distance visual acuity was 20/18 with -0.25, -0.25 × 80 in the right eye, and 20/20 with +0.25 -0.5 × 50 in the left eye. The case suggests that small-incision lenticule extraction can be an effective alternative for correcting myopic astigmatism in patients with nystagmus.

Background To introduce the Chung’s swing technique for small-incision lenticule extraction (SMILE). Methods A total of 112 eyes of 56 patients were included in this study. Patients were divided into two groups: 52 eyes of 26 patients were treated with SMILE using a traditional method (traditional group) and 60 eyes of 30 patients were treated with SMILE using the Chung’s swing technique (swing group). Results At 1 month postoperatively, all eyes in both groups had an uncorrected distance visual acuity of 20/20 or better. The efficacy indices were 1.09 ± 0.17 and 1.02 ± 0.11 (p = 0.492), and the safety indices were 1.12 ± 0.14 and 1.09 ± 0.15 (p = 0.537), for the traditional and swing group, respectively. All eyes in both groups underwent successful lenticule extraction; all lenticules were intact and complete. The mean lenticule extraction times were 48.67 ± 4.9 and 39.8 ± 5.53 s, for the traditional and swing group, respectively (p

Considerations of massive neutrinos, baryogenesis as well as fermion mass textures in the grand unified theory framework provide strong motivations for supersymmetric(SUSY) SO(10) as the theory beyond the standard model. If one wants to simultaneously solve the strong CP problem via the Peccei-Quinn mechanism, the most natural way to implement it within the framework of the SUSY SO(10) model is to have an intermediate scale ($v_{BL}$) (corresponding to B-L symmetry breaking) around the invisible axion scale of about 10$^{11}$ - 10$^{12}$ GeV. Such a scale is also desirable if $\nu_{\tau}$ is to constitute the hot dark matter (HDM) of the universe. In this paper, we discuss examples of superstring inspired SUSY SO(10) models with intermediate scales that are consistent with the low energy precision measurements of the standard model gauge couplings. The hypothesis of $b-\tau$ unification which is a successful prediction of many grand unified theories is then required of these models and the resulting prediction of $b$-quark mass is used as a measure of viability of these schemes. Detailed analysis of a model with a $v_{BL}\simeq 10^{11}$ GeV, which satisfies both the requirements of invisible axion and $\nu_{\tau}$ as HDM is presented and shown to lead to $m_b\simeq 4.9$ GeV in the one-loop approximation., Comment: Latex file; 20 pages; Four figures available on request

The relationship between the Dirac gamma (γ) matrices and the fundamental representations of the algebra sp(4,R) are clarified, which is locally isomorphic to the de Sitter algebra o(3,2). There are six sets of ten γ‐matrices among the fifteen traceless γ‐matrices, which satisfy the algebra sp(4,R). The representations can be identified with, and transformed into, one another through the permutation group of three objects S3. While each element of the invariant subgroup of S3 transforms an o(3,2)‐like sp(4,R) representation into another o(3,2)‐like sp(4,R), any other element of S3 transforms an o(3,2)‐like sp(4,R) into an o(2,3)‐like sp(4,R), and vice versa. We discuss physical implications of this group‐theoretical analysis.

We construct a supersymmetric SO(10) model, where natural doublet-triplet splitting implemented via the Dimopoulos-Wilczek mechanism is stable under the addition of 126+\bar{126} Higgs superfields needed to generate the small neutrino masses via the see-saw mechanism and where both the charged fermion and neutrino masses arise from just one set of 10 and \bar{126} multiplets., Comment: UMD-PP-94-50, Latex,9 pages

The vacuum conditions for preserving supersymmetry in the minimal supersymmetric SO(10) grand unified theory are constructed and studied. The mass spectrum for each symmetry-breaking chain which preserves supersymmetry is considered. It is found that in the minimal supersymmetric SO(10) grand unified theory only one-step symmetry breaking is allowed, whether or not supersymmetry remains unbroken in an intermediate symmetry breaking.

Purpose: To report a case of suction loss during small incision lenticule extraction (SMILE) and a good visual outcome after switching to femtosecond laser-assisted in-situ keratomileusis (LASIK). Case summary: A 20-year-old female was admitted to receive refractive surgery. During SMILE in the left eye, suction loss occurred at 65% of posterior cut completion. We switched to LASIK and SMILE was performed in the right eye as planned. The uncorrected distance visual acuity was 1.2 with a manifest refraction of +0.25 Dsph with 0 Dcyl. The patient had no complications at 3 months postoperatively. Conclusions: Suction loss during SMILE is a rare complication. Good visual outcome was achieved by switching to LASIK. J Korean Ophthalmol Soc 2015;56(8):1274-1277

In automatic [ital R]-parity-conserving supersymmetric (SUSY) SO(10) models, the simplest way to accommodate realistic fermion masses is to demand that the light Higgs doublets are linear combinations of the [l brace]10[r brace] and [l brace]12[bar 6][r brace] grand unified Higgs representations. We study the realization of this mixed light Higgs property consistent with doublet-triplet splitting in a minimal [ital R]-conserving SUSY SO(10) model. We then discuss predictions for neutrino masses and mixings in this model as well as its implications for proton decay.

We develop a general method for analyzing the renormalization group equations (RGE's) to one-loop and two-loop order in grand unified theories (GUT's) which can have an arbitrary number of symmetry-breaking scales and/or mass scales. The method is more efficient, convenient, and accurate than the current method for determining the ranges of symmetry-breaking scales and/or mass scales, as well as the ranges of unified gauge couplings. It does not involve the usual numerical integration of the RGE's at all, but in fact solves the RGE's analytically by a perturbative approach. The results are presented graphically and analyzed using simple geometrical considerations. We apply the method to two-step symmetry-breaking chains of SO(10) GUT's and compare the results with those obtained by numerical integration. We discover that the numerical method itself often introduces errors which are comparable with two-loop corrections. Our method avoids these. We also apply our method to two-step symmetry-breaking chains of supersymmetric SO(10) GUT's.

We present our best estimates of the uncertainties due to heavy particle threshold corrections on the unification scale $M_U$, intermediate scale $M_I$ and coupling constant Alpha_U in the minimal non-supersymmetric SO(10) models. Using these , we update the predictions for proton life-time in these models., UMD-PP-94-117 ( 20 pages;latex; no figures )

The simplest scenario for the three known light neutrinos that fits the solar and atmospheric neutrino deficit and a mixed dark matter (MDM) picture of the universe requires them to be highly degenerate with $m_{\nu} \sim$ 1 - 2 eV. We propose an SO(10) grand unified model with an S$_{4}$-horizontal symmetry that leads naturally to such a scenario. An explicit numerical analysis of the quark and lepton sector of the model shows that it can lead to desired mass differences to fit all data only for the small angle non-adiabatic MSW solution to the solar neutrino puzzle., Comment: UMD-PP-94-95; (Latex file; 1 figure available on request)

Purpose: To evaluate the clinical characteristics and results of outcomes in different types of orbital pseudotumor. Methods: This study included 62 patients diagnosed with orbital pseudotumor between 2002 and 2007, who were followed-up for more than 6 months. The pseudotumor was classified into anterior, diffuse, apical, myositic, or lacrimal types according to computed tomography (CT) findings. All patients were initially treated with corticosteroids and checked for symptom improvement and response to the corticosteroids. Results: Lacrimal type pseudotumor (61%, 39/62) showed the highest incidence, and lid swelling (97%, 60/62) was the most common symptom. Response rate to corticosteroid treatment was 84%, and the recurrence rate was 29%. Conclusions: The orbital pseudotumors were localized by computed tomography and classified to compare the symptoms, treatment efficacy and recurrence rates between the different types. The orbital pseudotumor is most commonly diagnosed based on clinical symptomsand radiologic features without biopsy. The orbital pseudotumor showed a good treatment response but also a high recurrence rate. Therefore, when starting treatment, it is important to consider differential diagnosis. It is recommended to carefully examine patients who have lid swelling for a few weeks with computed tomography before using corticosteroid treatment.