Demyelinating Neuropathy with Markedly Elevated Serum IgG4 Levels and Anti-Contactin 1 IgG4 Antibody.

We herein report a 77-year-old man with a 4-month history of progressive gait and sensory disturbances of the extremities. A nerve conduction study indicated demyelinating polyneuropathy. Serum IgG4 levels and anti-contactin 1 IgG4 antibodies were markedly increased. The sural nerve biopsy specimen showed IgG4-positive plasma cell infiltration in the epineurium. Treatment with steroids resulted in an amelioration of functional status, improvement of nerve conduction parameters, decreased serum IgG4 levels, and negative conversion of anti-contactin 1 antibody. Further studies are needed to clarify the significance of IgG4-positive plasma cell infiltration in anti-contactin 1 antibody-positive neuropathies.

Numerous spindle-shaped lymphoma cells in lymphomatosis cerebri: An autopsy case report.

Lymphomatosis cerebri (LC) is a rare variant of primary central nervous system lymphoma (PCNSL). It is characterized by diffuse infiltration of atypical lymphoid cells with no mass formation and little or no contrast enhancement on magnetic resonance imaging (MRI). Interestingly, some lymphoma cells form characteristic spindle shapes; these cells are found in some variants of malignant lymphoma, such as primary cutaneous follicle center lymphoma, but they have not been reported in PCNSL or LC. Here, we provide an autopsy case report of LC in a 69-year-old immunocompetent man who developed rapidly progressive cognitive decline and died on day 68 after the episode despite treatment with intravenous methylprednisolone administration. MRI revealed high signal intensities on T2-weighted images of the cerebral hemispheres, cerebellum, brainstem, and spinal cord without gadolinium enhancement on T1-weighted images. On autopsy, diffuse infiltrative atypical cells were seen; these cells were positive for CD20 and CD79a and negative for GFAP, CD3, and CD5 on immunohistochemistry, resulting in a diagnosis of diffuse large B-cell lymphoma, specifically LC. We found characteristic spindle-shaped cells, especially in the cerebral cortex. This is the first report showing that lymphoma cells in PCNSL can take on a spindle-shaped form. It is difficult to recognize these spindle-shaped cells as lymphoma cells on hematoxylin and eosin staining and diagnose them correctly with small biopsy specimens without immunohistochemistry. This case suggests that we should add atypical, spindle-shaped cells to the differential diagnosis of PCNSL.

Combined laser in-situ keratomileusis and accelerated corneal cross-linking: an update.

PURPOSE OF REVIEW: The purpose is to review the literature of combined laser in-situ keratomileusis (LASIK) and accelerated corneal collagen cross-linking (CXL) in context of its indications-contraindications, kerato-refractive, visual and safety outcomes, particularly with reference to preventing the development of post-LASIK ectasia. RECENT FINDINGS: LASIK + accelerated CXL has been developed with the rationale that the addition of CXL after LASIK may strengthen the LASIK compromised corneal biomechanics and minimize the complications such as post-LASIK ectasia. Different clinical studies have documented the safety and efficacy of LASIK + accelerated CXL for the correction of myopia or hyperopia and in the patients with low predicted residual bed thickness. SUMMARY: Available literature shows that refractive and keratometric outcomes of LASIK + accelerated CXL are comparable or better than LASIK alone. Less regression has been observed after LASIK + accelerated CXL compared with LASIK alone and no case of post-LASIK ectasia development has been reported among 673 eyes with the follow-up ranging from 3 months to 4.5 years. Future studies with large numbers of patients and longer postoperative follow-ups are needed to establish the efficacy of LASIK + accelerated CXL in preventing the development of post-LASIK ectasia.

Pupil Influence on the Visual Outcomes of a New-Generation Multifocal Toric Intraocular Lens With a Surface-Embedded Near Segment.

PURPOSE: To evaluate the influences of preoperative pupil parameters on the visual outcomes of a new-generation multifocal toric intraocular lens (IOL) model with a surface-embedded near segment. METHODS: In this prospective study, patients with cataract had phacoemulsification and implantation of Lentis Mplus toric LU-313 30TY IOLs (Oculentis GmbH, Berlin, Germany). The visual and optical outcomes were measured and compared preoperatively and postoperatively. The correlations between preoperative pupil parameters (diameter and decentration) and 3-month postoperative visual outcomes were evaluated using the Spearman's rank-order correlation coefficient (Rs) for the nonparametric data. RESULTS: A total of 27 eyes (16 patients) were enrolled into the current study. Statistically significant improvements in visual and refractive performances were found after the implantation of Lentis Mplus toric LU-313 30TY IOLs (P < .05). Statistically significant correlations were present between preoperative pupil diameters and postoperative visual acuities (Rs > 0; P < .05). Patients with a larger pupil always have better postoperative visual acuities. Meanwhile, there was no statistically significant correlation between pupil decentration and visual acuities (P > .05). CONCLUSIONS: Lentis Mplus toric LU-313 30TY IOLs provided excellent visual and optical performances during the 3-month follow-up. The preoperative pupil size is an important parameter when this toric multifocal IOL model is contemplated for surgery.

Evaluating the different laser fragmentation patterns used in laser cataract surgeries in terms of effective phacoemulsification time and power.

PURPOSE: To evaluate the effects of the different fragmentation patterns for the lens nucleus in terms of the effective phacoemulsification time (EPT) and power. SETTING: Shinagawa LASIK Center, Tokyo, Japan. DESIGN: Comparison study. METHODS: Seventy-one eyes of 71 patients had preoperative lens opacity grading based on the Emery-Little Classification (Grade 1 and Grade 2). Eyes underwent femtosecond laser-assisted cataract surgery (Catalys™ Precision Laser System), for capsulotomy and lens fragmentation. For the lens fragmentation, either the quadrants softened (Quadrant) or the quadrants complete (Complete) pattern was used. The mean EPT and phacoemulsification (phaco) power for each cutting pattern of Grades 1 and 2 cataracts were evaluated. RESULTS: The mean EPT was 28.96 seconds in the Quadrant Group and 16.31 seconds in the Complete Group (P=0.006). The mean phaco power was 8.07% in the Quadrant Group and 4.77% in the Complete Group (P=0.0002). Comparing the Quadrant and Complete Groups of Grade 1 cataract showed no significant difference in EPT (P=0.16), but showed a significant difference in phaco power (P=0.033). Comparing the Quadrant and Complete patterns of Grade 2 cataract showed significant differences in both EPT (P=0.012) and phaco power (P=0.003). Using the Complete pattern showed a 44.7% reduction in EPT and a 40.9% reduction in phaco power when compared to the Quadrant Group. CONCLUSION: Using the smaller fragmentation pattern in femtosecond laser cataract surgery, the phaco time and power were reduced significantly when compared to the procedure with the larger fragmentation pattern.

Visual and optical performances of multifocal intraocular lenses with three different near additions: 6-month follow-up.

PURPOSE: To compare the visual and optical outcomes of four multifocal intraocular lenses (IOLs) with three different near additions of +3.00 diopters (D), +3.75 D and +4.00 D. METHODS: In this prospective study, 133 eyes of 88 patients were implanted with one of the following IOLs: AcrySof(®) ReSTOR(®) SN6AD1 (+3.00 D) for Group A, Acriva(UD) Reviol BB MF 613 or BB MFM 611 (+3.75 D) for Group B, and AcrySof(®) ReSTOR(®) SN6AD3 (+4.00 D) for Group C. The visual acuity, refraction, intraocular pressure, tomography and corneal endothelial cell density (ECD) were compared between the three groups preoperatively and at 6 month postoperatively. Defocus curve, contrast sensitivity and higher order aberrations (HOAs) at 6 month postoperative visit were measured and compared. RESULTS: There were no statistically significant differences in distance visual acuity, refraction, intraocular pressure or ECD among the three groups after 6 months (P > 0.05). The photopic contrast sensitivity in Group C was statistically better than in Group A (P < 0.05). The scotopic ocular aberration in Group B was statistically greater compared to that in Group A (P < 0.05). The highest near-visual peaks were -0.06 logMAR at a -2.50 D (40 cm) in Group A, -0.07 logMAR at -3.00D (33 cm) in Group B, and -0.06 logMAR at -3.50 D (29 cm) in Group C. Statistically significant differences in near and intermediate visual acuities were observed among the three groups at -2.00 D (50 cm), -2.50 D (40 cm), -3.50 D (29 cm) and -4.00 D (25 cm) (P < 0.01). CONCLUSION: AcrySof(®) ReSTOR(®) SN6AD1 IOLs (+3.00 D) and SN6AD3 (+4.00 D) IOLs provided the best intermediate and near vision, respectively. Both intermediate and near vision were comparatively better in the eyes with Acriva(UD) Reviol BB MFM 611 IOLs or BB MF 613 IOLs (+3.75 D).

Two target locations for corneal inlay implantation combined with laser in situ keratomileusis.

PURPOSE: To compare the visual acuity outcomes between 2 target locations for corneal inlay implantation with concurrent laser in situ keratomileusis (LASIK) to compensate for presbyopia. SETTING: Shinagawa LASIK Center, Tokyo, Japan. DESIGN: Retrospective cohort study. METHODS: Bilateral LASIK was performed simultaneously with inlay implantation in the nondominant eye. The preoperative and 6-month postoperative uncorrected distance (UDVA) and uncorrected near (UNVA) visual acuities were evaluated. Patients were divided into the following 2 groups based on the pupil center to Purkinje reflex distance (Pp-Pk): small (≤300 µm) and large (>300 µm). Each group was divided into subgroups according to the distance of the inlay center to the Purkinje reflex (I-Pk) or to the midpoint between the pupil center and Purkinje reflex (I-M). The inlay position was classified as 0 to 100 µm, 101 to 200 µm, 201 to 300 µm, and 301 to 400 µm from the Purkinje reflex and from the midpoint. RESULTS: Of 1008 patients, 992 were available for postoperative follow-up. The UDVA and UNVA improved in both subgroups with all inlay positions (P < .0001). There were no statistically significant differences in UDVA or UNVA within or between the small Pp-Pk group and the large Pp-Pk group (P > .05). The Spearman rank-order correlation showed weak associations between the inlay distance and visual acuity. CONCLUSION: The amount of inlay decentration had no influence on postoperative visual acuity. FINANCIAL DISCLOSURE: Dr. Tomita is a consultant to Acufocus, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

One-year results of simultaneous laser in situ keratomileusis and small-aperture corneal inlay implantation for hyperopic presbyopia: comparison by age.

PURPOSE: To compare by age the safety, efficacy, and patient satisfaction after simultaneous laser in situ keratomileusis (LASIK) and small-aperture corneal inlay implantation (Kamra) for hyperopic presbyopia. SETTING: Shinagawa LASIK Center, Tokyo, Japan. DESIGN: Retrospective comparative cohort study. METHODS: Simultaneous LASIK and small-aperture corneal inlay implantation were performed in the nondominant eye of hyperopic presbyopic patients with astigmatism. Patients were divided into groups by age as follows: Group 1 (40 to 49 years), Group 2 (50 to 59 years), and Group 3 (60 to 65 years). The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, uncorrected near visual acuity (UNVA), and patient questionnaire results were compared. RESULTS: The study evaluated 277 eyes of 277 patients. All groups achieved a mean UDVA of 20/20, with Group 1, Group 2, and Group 3 gaining 1 line, 2 lines, and 3 lines, respectively. The mean UNVA was J2 with 4 lines gained in Group 1 and J3 with 5 lines gained in Group 2 and Group 3. The mean CDVA and corrected near visual acuity remained the same as at baseline. CONCLUSIONS: Simultaneous LASIK and small-aperture corneal inlay implantation for hyperopic presbyopia was a safe and effective treatment option. Although the outcomes were comparable between groups, Group 3 had the largest gain in UDVA and UNVA and the highest patient satisfaction, despite having the lowest reduction in dependence on reading glasses. Taking age into account might help achieve optimum postoperative outcomes and improved patient satisfaction. FINANCIAL DISCLOSURE: Dr. Tomita is a consultant to Ziemer Ophthalmic Systems AG, Acufocus, Inc., and Schwind eye-tech-solutions GmbH and Co. KG. Dr. Waring is a consultant to Acufocus, Inc.

Retrospective evaluation of the influence of pupil size on visual acuity after KAMRA inlay implantation.

PURPOSE: To investigate the influence of pupil size on visual acuity after KAMRA inlay (AcuFocus, Inc., Irvine, CA) implantation. METHODS: Five hundred eighty-four presbyopic eyes of 584 patients who underwent LASIK were evaluated. Uncorrected near visual acuity (UNVA), uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and corrected near visual acuity (CNVA) were measured. Two groups were classified: small pupil (pupil diameter < 6 mm) and large pupil (pupil diameter ≥ 6 mm) for both mesopic (pupil diameter < 4 mm) and photopic (pupil diameter ≥ 4 mm) pupil size parameters. The follow-up period was 6 months. RESULTS: There were no significant differences in UNVA (P = .98) and CNVA (P = .16) between the mesopic pupil size groups; however, there were significant differences in UDVA (P = .023) and CDVA (P = .039). There was a weak correlation between pupil size and UDVA of the large mesopic pupil size group (rs = 0.129, P = .04). There were no significant differences in UNVA (P = .78), CNVA (P = .92), UDVA (P = .19), and CDVA (P = .60) for the photopic pupil size groups. CONCLUSIONS: Pupil size does not have an influence on the resultant visual acuity after KAMRA inlay implantation. No correlation was found between preoperative and postoperative pupil size and visual acuity for the mesopic pupil groups.

Evaluating the short-term results of KAMRA inlay implantation using real-time optical coherence tomography-guided femtosecond laser technology.

PURPOSE: To evaluate the outcomes from using real-time optical coherence tomography (OCT)-guided femtosecond laser technology for pocket creation for KAMRA inlay (Acufocus, Inc., Irvine, CA) implantation surgery. METHODS: One hundred fifty-one eyes underwent KAMRA inlay implantation using the real-time OCT-guided femtosecond laser for pocket creation. All patients had a history of prior LASIK. Uncorrected distance visual acuity, corrected distance visual acuity, uncorrected near visual acuity, corrected near visual acuity, and manifest refraction spherical equivalent were evaluated preoperatively and postoperatively. The follow-up period was 3 months. RESULTS: Mean manifest refraction spherical equivalent, uncorrected distance visual acuity, and uncorrected near visual acuity changed from -0.18 ± 0.33 to -0.95 ± 0.64, 20/16 to 20/20, and J8 to J2, respectively. Corrected distance visual acuity and corrected near visual acuity remained stable before and after KAMRA inlay implantation, 20/12 and J1, respectively. CONCLUSIONS: Using real-time OCT-guided femtosecond laser technology increases the safety and accuracy of corneal KAMRA inlay implantation surgery with a history of prior LASIK with excellent visual and refractive outcomes.

Visual and optical performance of diffractive multifocal intraocular lenses with different haptic designs: 6 month follow-up.

PURPOSE: To evaluate and compare the visual acuity outcomes and optical performances of eyes implanted with two diffractive multifocal intraocular lens (IOL) models with either a plate haptic design or a modified-C design. METHODS: This retrospective study comprised cataract patients who were implanted with either a plate haptic multifocal IOL model (Acriva(UD) Reviol BB MFM 611 [VSY Biotechnology, Amsterdam, the Netherlands], group 1) or a modified-C haptic multifocal IOL model (Acriva(UD) Reviol BB MF 613 [VSY Biotechnology, Amsterdam, the Netherlands], group 2) between June 2012 and May 2013. The 6 month postoperative visual acuity, refraction, defocus curve, contrast sensitivity, and wave-front aberration were evaluated and compared between these eyes, using different IOL models. RESULTS: One hundred fifty-eight eyes of 107 patients were included in this study. Significant improvement in visual acuities and refraction was found in both groups after cataract surgery (P<0.01). The visual acuity and contrast sensitivity were statistically better in group 1 than in group 2 (P<0.01). No statistically significant difference in the corneal higher-order aberrations was found between the two groups (P>0.05). However, the ocular higher-order aberrations in group 2 were significantly greater than in group 1 (P<0.05). CONCLUSION: At 6 months postoperatively, both Acriva(UD) Reviol BB MFM 611 IOL and Acriva(UD) Reviol BB MF 613 IOL achieved excellent visual and refractive outcomes. The multifocal IOL model with plate haptic design resulted in better optical performances than that with the modified-C haptic design.

In vivo confocal laser microscopy of morphologic changes after simultaneous LASIK and accelerated collagen crosslinking for myopia: one-year results.

PURPOSE: To evaluate the safety of corneal collagen crosslinking (CXL) combined with laser in situ keratomileusis (LASIK). SETTING: Shinagawa LASIK Center, Tokyo, Japan. DESIGN: Case series. METHODS: Bilateral myopic LASIK patients had unilateral accelerated CXL (KXL System) in the nondominant eye. After LASIK, riboflavin 0.1% was instilled in the residual stromal bed for 60 seconds. After the riboflavin was washed out and the flap placed in its original position, ultraviolet-A light (30 mW/cm(2)) was administered for 60 seconds. The LASIK-CXL eyes and the LASIK-only eyes were compared. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, manifest refraction spherical equivalent (MRSE), keratometry values, endothelial cell density (ECD), pachymetry, optical coherence tomography (OCT), corneal hysteresis (CH), corneal resistance factor (CRF), keratoconus match index (KMI), and 37 parameters from a dynamic bidirectional applanation device (Ocular Response Analyzer) were analyzed. Morphologic changes were evaluated using confocal microscopy. RESULTS: No significant differences in UDVA, CDVA, MRSE, ECD, dynamic bidirectional applanation readings (eg, CH, CRF, KMI), or 37 additional parameters were found between the 2 groups (P>.05). Increased hyperreflectivity and a demarcation line similar to that seen after CXL were observed in the LASIK-CXL eyes. The demarcation line (mean depth 200.04 µm ± 27.01 [SD]; range 178 to 278 µm) was present in 23 eyes (95.8%); the line was well defined in 2 eyes (8.3%) and faint in 21 eyes (87.5%). CONCLUSION: Combined LASIK-CXL was safe, causing insignificant corneal biomechanical and morphologic changes similar to those with CXL treatment only. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Accelerated versus conventional corneal collagen crosslinking.

PURPOSE: To compare the outcomes of accelerated corneal collagen crosslinking (CXL) and conventional corneal CXL. SETTINGS: Private practice, Tokyo, Japan. DESIGN: Comparative study. METHODS: Eyes with keratoconus had accelerated CXL (KXL system; 15 minutes riboflavin [Vibex Rapid] presoak; 3 minutes 30 mW/cm(2) ultraviolet-A [UVA] light) or conventional CXL (CCL-365 Vario system; 30 minutes riboflavin [Vibex] presoak; 30 minutes 3 mW/cm(2) UVA light). The postoperative changes in visual acuity, keratometry readings, morphologic changes in the cornea, demarcation line existence, and corneal biomechanical responses with accelerated CXL and conventional CXL were compared. The follow-up was 1 year. RESULTS: The study enrolled 48 eyes of 39 patients; 30 eyes had accelerated CXL, and 18 eyes had conventional CXL. There were no statistically significant differences in postoperative changes in uncorrected or corrected distance visual acuity or in the manifest refraction spherical equivalent between the 2 procedures. There were also no statistically significant differences in the postoperative changes in the keratometric readings from the Pentacam Scheimpflug device or the corneal biomechanical responses from a dynamic bidirectional applanation device (Ocular Response Analyzer) or a dynamic Scheimpflug analyzer (Corvis ST) between the procedures. Similar morphologic changes and a pronounced demarcation line were apparent in eyes in both groups postoperatively. CONCLUSIONS: Accelerated CXL and conventional CXL were both safe and effective. Accelerated CXL, being a fast procedure, appears to be more beneficial for patients and surgeons. FINANCIAL DISCLOSURE(S): No author has a financial or proprietary interest in any material or method mentioned.

High-irradiance accelerated collagen crosslinking for the treatment of keratoconus: six-month results.

PURPOSE: To evaluate the effectiveness of accelerated corneal collagen crosslinking (CXL) with riboflavin for keratoconus by the change in dioptric power and corneal topography. SETTING: Private practice, Tokyo, Japan. DESIGN: Case series. METHODS: The accelerated CXL treatments (KXL system) were performed using a 10-minute riboflavin 0.1% (Vibex Rapid) soak and a 3-minute ultraviolet-A (UVA) irradiance at a level of 30 mW/cm(2). This corresponds to a total radiant exposure of 5.4 J/cm(2). Preoperative and 1, 3, and 6 months postoperative examinations were performed. RESULTS: The study enrolled 39 eyes of 22 patients. The mean uncorrected distance visual acuity showed a statistically significant improvement, from 1.11 ± 0.42 logMAR preoperatively to 0.89 ± 0.53 logMAR 6 months postoperatively (P<.01). The mean maximum keratometry readings also changed significantly, from 49.95 ± 6.11 diopters (D) preoperatively to 49.19 ± 5.82 D at 6 months (P<.01). There were no statistically significant changes in the endothelial cell density between preoperatively and postoperatively. CONCLUSIONS: The changes after accelerated CXL were similar to those after conventional CXL. Thus, accelerated CXL has the potential to efficiently treat and halt the progression of keratoconus and may be an effective, efficient therapeutic option for treating corneal ectatic disease. FINANCIAL DISCLOSURES: No author has a financial or proprietary interest in any material or method mentioned.

Outcomes of small aperture corneal inlay implantation in patients with pseudophakia.

PURPOSE: To evaluate the improvement in near visual acuity after KAMRA corneal inlay (AcuFocus, Inc., Irvine, CA) implantation in patients with pseudophakia. METHODS: A retrospective study analysis of patients with pseudophakia undergoing monocular corneal inlay implantation in the non-dominant eye was performed. The inlay was implanted monocularly in the non-dominant eye of patients. Manifest refractive spherical equivalent, uncorrected distance visual acuity, corrected distance visual acuity, uncorrected near visual acuity, and corrected near visual acuity were evaluated. The follow-up period was 3 months. RESULTS: Thirteen eyes from 13 patients were evaluated. Four patients underwent LASIK for improved distance acuity at the time of inlay implantation. Mean uncorrected near visual acuity improved five lines (from J10 to J4) postoperatively. Mean uncorrected distance visual acuity, corrected distance visual acuity, and corrected near visual acuity remained stable and were 20/20, 20/16, and J1, respectively, before and after KAMRA implantation. Three eyes lost two lines and 1 eye lost one line of uncorrected distance visual acuity. Two eyes lost two lines and 1 eye lost 1 line of corrected distance visual acuity. Mean manifest refractive spherical equivalent changed before and after KAMRA implantation from -0.01 ± 1.07 diopters (D) (range: 2.25 to -1.88 D) to -1.12 ± 0.87 D (range: 0.25 to -2.75 D), respectively. CONCLUSIONS: Implantation of a small aperture corneal inlay improved uncorrected near visual acuity while maintaining uncorrected and corrected distance visual acuity in monofocal patients with pseudophakia.

Comparative study of 2 types of implantable collamer lenses, 1 with and 1 without a central artificial hole.

PURPOSE: To compare the outcomes between implantable collamer lenses (ICLs), 1 with and 1 without a central artificial hole. DESIGN: Comparative study. METHODS: We included 65 eyes of 65 patients with refractive error in our study. The mean manifest refraction spherical equivalent (MRSE) was -9.32 ± 4.02 diopters (range, 6.75 to -16.50 diopters). We divided patients into 2 groups based on the type of ICL used, 1 for those without a central artificial hole (Group I, 21 eyes) and 1 for those with a hole (Group II, 44 eyes). The postoperative changes in visual acuity, endothelial cell density, MRSE, higher order aberrations readings, and objective scatter index between the 2 kinds of ICLs were compared. The follow-up period was 3 months. RESULTS: There were no statistically significant differences in the postoperative changes in uncorrected distance visual acuity (P = 0.81), corrected distance visual acuity (P = 0.24), MRSE (P = 0.18), and endothelial cell density (P = 0.76) between the groups. Also, no difference in objective scatter index was found at 3 months (P = 0.32). None of the higher order aberrations readings showed any significant difference between the groups. CONCLUSION: There were no significant differences between the outcomes of these ICLs, either with or without a central artificial hole.

Corneal biomechanics as a function of intraocular pressure and pachymetry by dynamic infrared signal and Scheimpflug imaging analysis in normal eyes.

PURPOSE: To evaluate corneal biomechanical deformation response using Ocular Response Analyzer (ORA) and Corvis ST data. DESIGN: Prospective observational case-control study. METHODS: A total of 1262 eyes of 795 patients were enrolled. Three groups were established, according to the corneal compensated intraocular pressure (IOPcc): Group I (10-13 mm Hg), Group II (14-17 mm Hg), and Group III (18-21 mm Hg). Each group included 3 subgroups, based on central corneal thickness (CCT): Subgroups 1 (465-510 µm), 2 (510-555 µm), and 3 (555-600 µm). In addition, similar groups of CCT were divided into subgroups of IOPcc. Corneal hysteresis (CH) and corneal resistance factor (CRF) were derived from ORA. The parameters of highest concavity with the parameters of first and second applanation were recorded from Corvis ST. RESULTS: CH and CRF, applanation 1 time, and radius of curvature at highest concavity showed significant differences between CCT subgroups for each IOPcc group (P < .0001). CH, applanation 1 and 2 time, and applanation 2 velocity, as well as deformation amplitude (DA), showed significant differences by IOP subgroups for all CCT groups. IOPcc is correlated negatively with CH (r = -0.38, P < .0001). There are positive correlations of IOPcc with applanation 1 time, applanation 2 velocity, and radius and negative correlations with applanation 2 time (r = -0.54, P < .0001), applanation 1 velocity (r = -0.118, P < .0001), and DA (r = -0.362, P < .0001). CONCLUSION: ORA and Corvis ST parameters are informative in the evaluation of corneal biomechanics. IOP is important in deformation response evaluation and must be taken into consideration.

Long-term observation and evaluation of femtosecond laser-assisted thin-flap laser in situ keratomileusis in eyes with thin corneas but normal topography.

PURPOSE: To evaluate the long-term outcomes of thin-flap laser in situ keratomileusis (LASIK) in eyes with thin corneas (central corneal thickness [CCT] <500 µm) but normal topography. SETTING: Private center, Tokyo, Japan. DESIGN: Retrospective randomized comparative study. METHOD: The efficacy, safety, predictability, and topography of LASIK were evaluated in eyes with a CCT of less than 500 µm but with normal topography (thin-cornea group) to 6 years postoperatively. The LASIK outcomes in the thin-cornea group were compared with those in eyes with a CCT of 500 µm or greater (control group). Analysis was performed to determine whether there were differences between the groups at the last checkup 3 to 4 years postoperatively. RESULTS: In the thin-cornea group (291 eyes; 146 patients), no significant differences were observed in LASIK outcomes when eyes were subdivided by the time of final checkup (3, 4, and ≥ 5 years). There was a significant difference in visual and refractive outcomes between 3 months postoperatively and the last checkup in the thin-cornea group and the control group (371 eyes; 193 patients). No significant difference in visual, refractive, or topography outcomes was observed between the 2 groups at the last checkup. CONCLUSIONS: Laser in situ keratomileusis in eyes with thin corneas was as safe and effective as and showed similar long-term stability in eyes with a CCT of 500 µm or greater. No eye in either group had a postoperative complication. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.