Corneal Dendritic Cell Dynamics Are Associated with Clinical Factors in Type 1 Diabetes.

Time-lapsed in vivo corneal confocal microscopy (IVCCM) has shown that corneal dendritic cells (DCs) migrate at approximately 1 µm/min in healthy humans. We have undertaken IVCCM of the whorl region to compare the density of rounded DCs, and DCs with (wDCs) and without (woDCs) dendrites and dynamics; trajectory (length travelled/time), displacement (distance from origin to endpoint/time) speeds and persistence ratio (displacement/trajectory) of woDCs in subjects with type 1 diabetes (T1D) (n = 20) and healthy controls (n = 10). Only the wDC density was higher (p = 0.

Corneal Confocal Microscopy Predicts the Development of Diabetic Neuropathy: A Longitudinal Diagnostic Multinational Consortium Study.

Objective: Corneal nerve fiber length (CNFL) has been shown in research studies to identify diabetic peripheral neuropathy (DPN). In this longitudinal diagnostic study, we assessed the ability of CNFL to predict the development of DPN.

Research Design And Methods: From a multinational cohort of 998 participants with type 1 and type 2 diabetes, we studied the subset of 261 participants who were free of DPN at baseline and completed at least 4 years of follow-up for incident DPN.

Association between conjunctival goblet cells and corneal resident dendritic cell density changes in new contact lens wearers.

Background: To explore the interlink between conjunctival goblet and corneal dendritic cell density after six months of lens wear and to predict dendritic cell migration to the central cornea based on goblet cell loss in the conjunctiva as a response to contact lens wear.

Methods: Sixty-nine subjects who had never previously worn contact lenses were observed for six months; 46 were fitted with contact lenses and 21 served as a control group. Corneal confocal microscopy was used to quantify goblet and dendritic cell density before and after six months of daily lens wear.

Rapid Corneal Nerve Fiber Loss: A Marker of Diabetic Neuropathy Onset and Progression.

Objective: Corneal nerve fiber length (CNFL) represents a biomarker for diabetic distal symmetric polyneuropathy (DSP). We aimed to determine the reference distribution of annual CNFL change, the prevalence of abnormal change in diabetes, and its associated clinical variables.

Research Design And Methods: We examined 590 participants with diabetes (399 with type 1 diabetes [T1D] and 191 with type 2 diabetes [T2D]) and 204 control patients without diabetes with at least 1 year of follow-up and classified them according to rapid corneal nerve fiber loss (RCNFL) if CNFL change was below the 5th percentile of the control patients without diabetes.

Corneal Nerve Migration Rate in a Healthy Control Population.

Purpose: The purpose of this study was to establish an age-dependent normative range and factors affecting the migration rate of the corneal subbasal nerve plexus in a healthy control population.

Methods: Corneal nerve migration rate was measured in 60 healthy participants grouped by age: A, aged 20 to 39 years (n = 20); B, 40 to 59 years (n = 20); and C, 60 to 79 years (n = 20). Laser-scanning corneal confocal microscopy was performed on the right eye of all participants at baseline and again after 3 weeks.

Corneal confocal microscopy for identification of diabetic sensorimotor polyneuropathy: a pooled multinational consortium study.

Aims/hypothesis: Small cohort studies raise the hypothesis that corneal nerve abnormalities (including corneal nerve fibre length [CNFL]) are valid non-invasive imaging endpoints for diabetic sensorimotor polyneuropathy (DSP). We aimed to establish concurrent validity and diagnostic thresholds in a large cohort of participants with and without DSP.

Methods: Nine hundred and ninety-eight participants from five centres (516 with type 1 diabetes and 482 with type 2 diabetes) underwent CNFL quantification and clinical and electrophysiological examination.

Corneal and Retinal Neuronal Degeneration in Early Stages of Diabetic Retinopathy.

Purpose: To examine the neuronal structural integrity of cornea and retina as markers for neuronal degeneration in nonproliferative diabetic retinopathy (NPDR).

Methods: Participants were recruited from the broader Brisbane community, Queensland, Australia. Two hundred forty-one participants (187 with diabetes and 54 nondiabetic controls) were examined.

Ophthalmic and clinical factors that predict four-year development and worsening of diabetic retinopathy in type 1 diabetes.

Aims: To investigate the role of ophthalmic imaging markers - namely retinal thickness measures and corneal nerve morphology - in predicting four-year development and worsening of diabetic retinopathy (DR) in type 1 diabetes (T1DM).

Methods: 126 eyes of 126 participants with T1DM were examined at baseline and after four years. Diabetic retinopathy (DR) was graded using the Early Treatment Diabetic Retinopathy Study scale.

Presence of Peripheral Neuropathy Is Associated With Progressive Thinning of Retinal Nerve Fiber Layer in Type 1 Diabetes.

Purpose: Reduced retinal nerve fiber layer (RNFL) thickness has been demonstrated in patients with diabetic peripheral neuropathy (DPN) in cross-sectional studies. This prospective study defines longitudinal alterations to the RNFL thickness in individuals with type 1 diabetes without (DPN-ve) and with (DPN+ve) DPN and in relation to risk factors for nerve damage.

Methods: A cohort of 105 individuals with type 1 diabetes (20% DPN+ve) with predominantly mild or no retinopathy and no previous retinal photocoagulation underwent spectral-domain optical coherence tomography (SD-OCT) at baseline, 2 years, and 4 years.

Optical coherence tomography predicts 4-year incident diabetic neuropathy.

Purpose: To examine the capability of optical coherence tomography-derived retinal thickness measures in detecting 4-year incident diabetic peripheral neuropathy (DPN).

Methods: 145 eyes of 145 participants with diabetes but no DPN at baseline were examined for incident DPN. HbA levels, nephropathy, neuropathy (DPN), cardiovascular measures, and various retinal thickness measures were examined at baseline and after 4 years.

Corneal confocal microscopy best identifies the development and progression of neuropathy in patients with type 1 diabetes.

A sub-set of 38 individuals with type 1 diabetes that fulfilled a strict criterion of "normal" classification for all 7 measures of neuropathy at baseline, were identified and followed. Corneal nerve morphology, as captured with corneal confocal microscopy demonstrated the greatest, and most sustained degeneration over a 4 year period.

Focal loss volume of ganglion cell complex in diabetic neuropathy.

Background: The aim was to investigate the relationship between diabetic peripheral neuropathy (DPN) and abnormalities in ganglion cell complex (GCC); specifically, focal loss volume (FLV) and global loss volume (GLV).

Methods: The ganglion cell complex was evaluated using optical coherence tomography on 193 individuals (84 with type 1 diabetes, 67 with type 2 diabetes and 42 without diabetes). In those with diabetes, 88 had diabetes but no diabetic retinopathy (no DR group) and 63 had diabetes with diabetic retinopathy (DR group).

Abnormal Anterior Corneal Morphology in Diabetes Observed Using In Vivo Laser-scanning Confocal Microscopy.

Purpose: To assess if diabetes alters corneal epithelial, anterior stromal and subbasal nerve plexus morphology and to determine the associations between these and other clinical variables.

Methods: A cohort of 78 participants with diabetes (39 with Type 1 and 39 with Type 2 diabetes) and 29 age-matched healthy controls underwent laser-scanning confocal microscopy of the central cornea. Intermediate cell density (ICD), basal cell density (BCD), anterior stromal cell density (ASCD), corneal nerve fiber density (CNFD) and nerve fiber length (CNFL) were quantified.

A rapid decline in corneal small fibers and occurrence of foot ulceration and Charcot foot.

We present clinical, neuropathy and corneal nerve morphology data in a participant with type 2 diabetes who developed diabetic foot ulceration, partial amputation and Charcot during a longitudinal observational study. While conventional measures of neuropathy did not deteriorate significantly, corneal nerve parameters showed a rapid reduction prior to the development of foot complications.

Diagnostic capability of retinal thickness measures in diabetic peripheral neuropathy.

Purpose: To examine the diagnostic capability of the full retinal and inner retinal thickness measures in differentiating individuals with diabetic peripheral neuropathy (DPN) from those without neuropathy and non-diabetic controls.

Methods: Individuals with (n=44) and without (n=107) diabetic neuropathy and non-diabetic control (n=42) participants underwent spectral domain optical coherence tomography (SDOCT). Retinal thickness in the central 1mm zone (including the fovea), parafovea and perifovea was assessed in addition to ganglion cell complex (GCC) global loss volume (GCC GLV) and focal loss volume (GCC FLV), and retinal nerve fiber layer (RNFL) thickness.

Characterization of Goblet Cells in a Pterygium Biopsy Using Laser Scanning Confocal Microscopy and Immunohistochemistry.

Purpose: To confirm that structures presumed to be GCs observed using laser scanning confocal microscopy (LSCM) are actually GCs.

Methods: A single tissue sample was obtained from a pterygium that was freshly excised from a 33-year-old male. After viewing what were believed to be GCs in the tissue sample using LSCM, the same sample was observed using laboratory confocal microscopy and immunohistochemistry.

Longitudinal changes in Langerhans cell density of the cornea and conjunctiva in contact lens-induced dry eye.

Background: The aim was to determine longitudinal changes in Langerhans cell density (LCD) in the human cornea and conjunctiva during asymptomatic and symptomatic contact lens wear.

Methods: Twenty-five participants with contact lens-induced dry eye (CLIDE) and 35 without CLIDE (NO-CLIDE), diagnosed using a range of symptom questionnaires and objective tests (tear film break up, cotton thread tear test and corneal staining) were enrolled. The central cornea and nasal bulbar conjunctiva were examined using a Heidelberg laser scanning confocal microscope at baseline and following one, four and 24 weeks wear of daily disposable hydrogel contact lenses.

Repeatability of Measuring Corneal Nerve Migration Rate in Individuals With and Without Diabetes.

Purpose: To assess the repeatability of measuring the corneal nerve migration rate in individuals with and without neuropathy.

Methods: Wide-field montages of the subbasal corneal nerve plexus were generated at baseline and after 3 weeks for 14 participants. Montages were manually examined side by side to identify a referent landmark in the inferior whorl region (origin) and throughout each montage.

Time Course of Changes in Goblet Cell Density in Symptomatic and Asymptomatic Contact Lens Wearers.

Purpose: To investigate longitudinal changes in goblet cell density (GCD) in contact lens (CL) wearers who do and do not develop symptoms of dry eye (DE).

Methods: Sixty healthy individuals fitted with daily disposable hydrogel CLs and 23 age-balanced non-CL-wearing controls underwent assessment using the 5-item dry eye questionnaire, noninvasive tear film break-up time measurement, ocular surface assessment, and phenol red thread test evaluation. Laser scanning confocal microscopy (LSCM) and conjunctival impression cytology (CIC) were used to assess GCD at baseline and follow-up visits at 1 week and 1 and 6 months.

Inflammatory Cell Upregulation of the Lid Wiper in Contact Lens Dry Eye.

Purpose: To determine if Langerhans cells in the lid wiper are upregulated in contact lens-induced dry eye (CLIDE).

Methods: The lid wiper of one eye of 17 participants with CLIDE (assessed using the CLDEQ-8) and 29 without CLIDE (NO-CLIDE) was examined using a Heidelberg laser scanning confocal microscope after 6 months wear of daily disposable hydrogel contact lenses (Biomedics 1 day Extra). Twenty non-contact-lens-wearing controls were also examined.

Development of a Novel Technique to Measure Corneal Nerve Migration Rate.

Purpose: We have developed a novel technique to measure in vivo corneal nerve migration.

Methods: Wide-field montages of the subbasal corneal nerve plexus were generated at baseline and after 3 weeks. The 2 montages were manually examined side by side to identify a referent landmark in the inferior whorl region and 20 additional nerve landmarks throughout each montage.

Retinal Tissue Thickness is Reduced in Diabetic Peripheral Neuropathy.

Aim: To investigate the relationship between diabetic peripheral neuropathy (DPN) and retinal tissue thickness.

Methods: Full retinal thickness in the central retinal, parafoveal, and perifoveal zones and thickness of the ganglion cell complex and retinal nerve fiber layer (RNFL) were assessed in 193 individuals (84 with type 1 diabetes, 67 with type 2 diabetes, and 42 healthy controls) using spectral domain optical coherence tomography. Among those with diabetes, 44 had neuropathy defined using a modified neuropathy disability score recorded on a 0-10 scale.

Changes in corneal Langerhans cell density during the first few hours of contact lens wear.

Purpose: To determine the impact of contact lens wear on Langerhans cell density (LCD) in the central cornea over an 8h period.

Methods: Ten participants wore a hydrogel lens in one eye (the experimental eye) for 8h. The contralateral non-lens-wearing eye served as a control.

Retinal tissue thickness in type 1 and type 2 diabetes.

Background: The objective was to investigate full retinal and inner retinal thickness in individuals with type 1 and type 2 diabetes.

Methods: Eighty-four individuals with type 1 diabetes (T1DM), 67 individuals with type 2 diabetes (T2DM) and 42 non-diabetic individuals (control group) were enrolled. Participants underwent full retinal thickness evaluation in the central retinal, parafoveal and perifoveal zones and in the retinal nerve fibre layer (RNFL) and ganglion cell complex (GCC), using spectral domain optical coherence tomography.

Assessment of conjunctival goblet cell density using laser scanning confocal microscopy versus impression cytology.

Purpose: To determine the association between conjunctival goblet cell density (GCD) assessed using in vivo laser scanning confocal microscopy and conjunctival impression cytology in a healthy population.

Methods: Ninety (90) healthy participants undertook a validated 5-item dry eye questionnaire, non-invasive tear film break-up time measurement, ocular surface fluorescein staining and phenol red thread test. These tests where undertaken to diagnose and exclude participants with dry eye.