A comparison of conventional and accelerated corneal crosslinking: corneal epithelial remodeling and in vivo confocal microscopy analysis.

PURPOSE: To evaluate the effect of conventional and accelerated corneal crosslinking (CXL) on visual acuity, corneal topography, corneal epithelial thickness, and subbasal nerve morphology in progressive keratoconus patients. METHODS: In this prospective and randomized study, twenty eyes of 20 patients were treated with conventional CXL (3 mW/cm2, 30 min, C-CXL) and 19 eyes of 19 patients were treated with accelerated CXL (9 mW/cm2, 10 min, A-CXL). The spherical equivalent, uncorrected visual acuity, best-corrected visual acuity, keratometric measurements, demarcation line measurement and epithelial thickness mapping analyses, and subbasal nerve morphology with in vivo confocal microscopy (IVCCM) were evaluated at baseline and at postoperative months 1, 3 and 6. RESULTS: At postoperative 6 months, a significant improvement was observed in all keratometric values in both treatment groups (p < 0.05). All epithelial thickness indices, except central, temporal, and inferotemporal thickness, were reduced at 1 month postoperatively in both treatment groups. The epithelial map uniformity indices (standard deviation and difference between min-max thickness) were significantly lower than the baseline values at all time points after CXL in both treatment groups (p < 0.001). Compared with the preoperative values, there was a significant decrease in all IVCCM parameters at 1 month postoperatively (p < 0.05). At 6 months postoperatively, corneal nerve fiber density and corneal nerve branch density recovered to preoperative values in the A-CXL group, whereas corneal nerve regeneration was not complete in the C-CXL group. CONCLUSION: Both conventional and accelerated CXL treatments appear to be effective in halting the progression of KC. Corneal epithelial irregularity slightly improves after CXL. The regeneration of subbasal nerves is faster after A-CXL treatment.

Identification of corneal and intra-epidermal axonal swellings in amyotrophic lateral sclerosis.

INTRODUCTION/AIMS: In patients with amyotrophic lateral sclerosis (ALS), axonal spheroids in motor axons have been identified in post-mortem studies. In this study, axonal spheroids and swellings on C-fibers of ALS patients were investigated using corneal confocal microscopy (CCM) and skin biopsy, respectively. METHODS: Thirty-one ALS patients and 20 healthy subjects were evaluated with CCM to assess corneal nerve-fiber length (CNFL), -fiber density (CNFD), -branch density (CNBD), dendritic cell (DC) density, and axonal spheroids originating from C-fibers (>100 µm2 ). In addition, intraepidermal nerve fiber density (IENFD) and axonal swellings (>1.5 µm) were assessed in skin biopsies obtained from the arms and legs of 22 patients and 17 controls. RESULTS: In ALS patients, IENFD, CNFD, CNFL, and CNBD were not different from controls. The density of DCs and the number of patients with increased DC density were higher in ALS patients than controls (p = .0005 and p = .008). The number of patients with axonal spheroids was higher than controls (p = .03). DISCUSSION: Evaluation of DCs and axonal bulbs in C-fibers of ALS patients could provide insights into pathophysiology or potentially serve as biomarkers in ALS.

Corneal nerve fiber involvement in chronic inflammatory demyelinating polyneuropathy.

BACKGROUND: Despite the primary myelin-related pathophysiology, small fiber neuropathy (SFN) and axonal degeneration are also considered to be involved and associated with disabling symptoms and impaired quality of life in chronic inflammatory demyelinating polyneuropathy (CIDP). Demonstration of SFN usually requires complex or invasive investigations. OBJECTS: In vivo corneal confocal microscopy (IVCCM) has evolved as a non-invasive, easily applied method for quantification of small fiber involvement in peripheral nerve disorders. We aimed to investigate the potential role of IVCCM in CIDP. METHODS: In this cross-sectional study, 15 patients with CIDP underwent assessment with clinical disability scales, neuropathic pain (NP) and autonomic symptom questionnaires, nerve conduction studies, and IVCCM. IVCCM parameters were analyzed and compared to those from 32 healthy controls. RESULTS: Corneal nerve fiber density (CNFD) and corneal nerve fiber length (CNFL) were significantly decreased in the CIDP group, compared to those in controls (p = 0.03 and p = 0.024, respectively). Langerhans cells and fiber tortuosity were increased in CIDP patients (p = 0.005 and p = 0.001, respectively). IVCCM parameters were significantly lower in patients with NP compared to those in patients without NP. CONCLUSION: IVCCM shows promise as a non-invasive complementary biomarker in the assessment of demyelinating polyneuropathies, providing insights into the potential pathophysiology of these non-length-dependent neuropathies.

In Vivo Corneal Confocal Microscopy in Multiple Sclerosis: Can it Differentiate Disease Relapse in Multiple Sclerosis?

PURPOSE: This study aims to investigate the role of in vivo corneal confocal microscopy (IVCCM) in the detection of corneal inflammatory activity and subbasal nerve alterations in patients with multiple sclerosis (MS) and to further determine whether IVCCM can be used to detect (acute) disease relapse. DESIGN: Prospective cross-sectional study, with a subgroup follow-up. METHODS: This single-center study included 58 patients with MS (MS-Relapse group [n = 27] and MS-Remission group [n = 31]), and 30 age- and sex-matched healthy control subjects. Patients with a history of optic neuritis or trigeminal symptoms were excluded. Corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), corneal nerve fiber length (CNFL), and dendritic cell (DC) density were evaluated in all patients with MS and control subjects by IVCCM. Patients in the MS-Relapse group who were in remission for ≥6 months after the MS incident underwent a repeat IVCCM. RESULTS: No statistical difference was observed between the MS-Relapse and MS-Remission groups regarding age, sex, MS duration, and the number of relapses (P > .05). Compared with healthy control subjects, all subbasal nerve parameters were significantly lower (CNFD: P < .001, CNFL: P < .001, CNBD: P < .001), and the DC density was significantly higher (P = .023) in patients with MS. However, no significant difference was observed between MS-Relapse and MS-Remission groups in terms of CNFD (mean [SE] difference -2.05 [1.69] fibers/mm2 [95% confidence interval {CI} -1.32 to 5.43]; P < .227), CNFL (mean [SE] difference -1.10 [0.83] mm/mm2 [95% CI -0.56 to 2.75]; P < .190), CNBD (mean [SE] difference -3.91 [2.48] branches/mm2 [95% CI -1.05 to 8.87]; P < .120), and DC density (median [IQR], 59.38 [43.75-85.0] vs 75.0 [31.25-128.75]; P = .596). The repeat IVCCM in relapse patients (n = 16 [59.3%]) showed a significant increase in CNFD (P = .036) and CNBD (P = .018), but no change was observed in CNFL (P = .075) and DC density (P = .469). CONCLUSION: Although increased inflammation and neurodegeneration can be demonstrated in patients with MS compared with healthy control subjects, a single time point evaluation of IVCCM does not seem to be sufficient to confirm the occurrence of relapse in patients with MS. However, IVCCM holds promise for demonstrating early neuroregeneration in patients with MS.

Clinical outcomes with a low add multifocal and an extended depth of focus intraocular lenses both implanted with mini-monovision.

OBJECTIVES: To compare the visual acuity, contrast sensitivity (CS), spectacle needs, photic phenomena, and quality of life parameters of patients bilaterally implanted with a low add multifocal (MIOL) or an extended depth of focus (EDOF) intraocular lens (IOL), both with intended mini-monovision. METHODS: In this prospective, randomized, comparative study, patients were randomized to receive either Tecnis +2.75 D (ZKB00) (MIOL Group, n = 15) or Tecnis Symfony (ZXR00) (EDOF Group, n = 14) for bilateral implantation with mini-monovision (-0.50 D). Binocular logMAR uncorrected visual acuities (UVA), monocular defocus curves, CS with CSV 1000-E, and Pelli-Robson Test (PRT), spectacle needs and quality of life parameters with NEI RQL-42 questionnaire were evaluated at postoperative 1, 3, and 6 months. RESULTS: Results of MIOL and EDOF Groups at postoperative month 6 are as follows: distance (6 m) UVA -0.03 ± 0.05 and -0.05 ± 0.06 (p = 0.938), intermediate (60 cm) UVA, 0.04 ± 0.08 and -0.03 ± 0.07 (p = 0.046); near (40 cm) UVA, 0.22 ± 0.08 and 0.15 ± 0.07 (p = 0.046); near spectacle needs, 26.7% and 14.3% (p > 0.05), respectively. Better visual acuity was achieved in the EDOF Group between the defocus range of -0.50 and -1.75 D (p < 0.05). No significant difference was found regarding photic phenomena and CS evaluated with CSV 1000-E between the two IOL groups at 6 months after surgery (otherwise there are differences at 1 and 3 months in favor of EDOF). However, EDOF Group performed better in mesopic CS evaluated with PRT (p < 0.05). CONCLUSIONS: When implanted with mini-monovision better binocular uncorrected visual performance at intermediate and near distances achieved with EDOF than low add MIOL.

Clinical Performance of Samfilcon A Contact Lenses in Intensive Digital Device Users: A Multicenter, Prospective Clinical Study.

INTRODUCTION: To evaluate patient satisfaction with samfilcon A contact lenses (CLs) in intensive digital device users with myopia and to compare patient satisfaction with samfilcon A lenses to prior experience with senofilcon A or lotrafilcon B CLs. METHODS: This was a comparative, prospective, national study conducted at 14 centers in Turkey. Subjects were adults aged 18 and 45 years with myopia (range -0.25 D to -6.00 D) who spend a minimum of 3 hours viewing digital devices (e.g., computer, smartphone). A subgroup of patients were habitual lens wearers (senofilcon A or lotrafilcon B lens wear for at least 6 months prior to enrollment). The primary assessment was patient satisfaction with samfilcon A lenses (0-100 Likert scale). Secondary assessments included patient satisfaction with samfilcon A lenses compared to patients' habitual lenses, investigator satisfaction with samfilcon A lenses and investigator-evaluated slit lamp examination findings. RESULTS: Samfilcon A lenses were given high overall ratings from both patients and investigators, with a low incidence of ocular symptoms. Overall, patients were highly satisfied with samfilcon A lenses for comfort, vision and overall performance, and stated that they would consider wearing these lenses in the future. Among habitual senofilcon A or lotrafilcon B lens wearers, samfilcon A lenses were rated significantly better than the habitual lenses in regard to comfort, vision and overall performance. Investigator assessments were also highly favorable, both at initial fit and after 4 weeks of follow-up, with no significant findings noted on slit lamp examination. CONCLUSION: Samfilcon A lenses were rated highly by investigators in regard to fit, handling and slit lamp findings, and by novice and habitual lens wearers in regard to comfort, vision and overall performance. These results support the use of samfilcon A lenses among digital device users who seek day-long comfort and good visual acuity.

Early detection of neuropathy in patients with type 2 diabetes with or without microalbuminuria in the absence of peripheral neuropathy and retinopathy.

PURPOSE: Our goal is early detection of neuropathy in patients with type 2 diabetes with or without microalbuminuria in the absence of diabetic retinopathy and peripheral neuropathy by using in vivo corneal confocal microscopy (IVCCM). METHODS: A total of 60 type-2 diabetic patients, assigned to either a diabetes mellitus (DM) with microalbuminuria group (DM/MA+, n=30) or a DM without microalbuminuria group (DM/MA-, n=30), and 30 age-matched control subjects were enrolled in this study. All cases underwent evaluation of blood glucose level, HbA1c, lipid fractions, body mass index (BMI), and corneal sensitivity (CS). Corneal nerve fiber length (NFL), nerve fiber density (NFD), nerve branch density (NBD), and tortuosity coefficient (TC) were quantified by IVCCM. None of the patients had peripheral neuropathy or retinopathy. RESULTS: Compared with the healthy subjects, NFL and NFD were reduced in both diabetic groups (P<0.0001), while NBD was significantly reduced in the DM/MA+ group. Between the diabetic groups, NFL, NFD, and NBD were significantly higher in the DM/MA- group (all P's<0.001). CS was significantly lower in DM/MA+ compared with DM/MA- and controls (both P's<0.0001). NFD and NFL were inversely correlated with age, triglyceride level, and BMI. CONCLUSION: These results indicate that significant damage to small nerves, quantified using IVCCM, can be detected in the absence of retinopathy, peripheral neuropathy or microalbuminuria in type 2 diabetic patients. The severity of corneal nerve involvement may further increase in the presence of nephropathy. This feature may also be valuable for early detection of microvascular complications of DM, allowing for the prevention of progression of life threatening microvascular complications.

Comparison of reading performance with low add bifocal and extended depth of focus intraocular lenses implanted with mini-monovision.

PURPOSE: To evaluate reading performance, preferred reading distance, and spectacle independence in patients implanted with a low add multifocal or an extended depth of focus (EDOF) intraocular lens (IOL) after phacoemulsification. METHODS: In this prospective study, patients were randomized into two groups: the diffractive multifocal Tecnis + 2.75 D (ZKB00) IOL (Tecnis + 2.75 group; 15 patients) or the EDOF Tecnis Symfony (ZXR00) IOL (Symfony group; 14 patients) for bilateral implantation with mini-monovision. Reading performance parameters (reading acuity [RA], critical print size [CPS], and maximum reading speed [MRS]) were evaluated with MNREAD acuity charts at 40 cm, and preferred reading distances and spectacle independence for near activities were assessed preoperatively and at the postoperative 1st, 3rd, and 6th months. RESULTS: At the postoperative 6th month, binocular logMAR UNVA and DCNVA were significantly better in the Symfony group than in the Tecnis + 2.75 group (UNVA: 0.15 ± 0.07 vs. 0.22 ± 0.08, p = 0.046; DCNVA: 0.21 ± 0.05 vs. 0.28 ± 0.07, p = 0.043; respectively). There was no significant difference in reading performance parameters between the groups; however, the Symfony group preferred significantly closer reading distance than the Tecnis + 2.75 group (42.00 ± 4.67 cm; 45.87 ± 5.32 cm, respectively, p = 0.030). At the postoperative 6th month, 14.3% and 26.7% of patients reported that they needed spectacles, rarely or occasionally, for near activities in the Symfony and Tecnis + 2.75 groups, respectively (p > 0.05). CONCLUSIONS: When implanted with mini-monovision, although functional near visual acuity and a high degree of spectacle independence at near distances were achieved with both IOLs, patients implanted with the EDOF IOL preferred closer reading distance than those implanted with the low add diffractive multifocal IOL.