Corneal endothelial cell density and morphology in patients with acromegaly

Long-term effect of using hard contact lenses on corneal endothelial cell density and morphology in ophthalmologically healthy individuals in Japan

The adverse effects of hard contact lenses (HCL) on the corneal endothelium have been studied in the short term; however, long-term effects remain still unclear. In this study, we analyzed the effect of long-term HCL use on corneal endothelial cell density (ECD) and morphology in healthy Japanese individuals. This cross-sectional observational study included individuals using HCL for refractive errors examined at a single specialty eye hospital. Patient age, duration of HCL usage, ECD, coefficient of variation of the cell area (CV), and rate of appearance of hexagonal cells (6A) obtained via non-contact specular microscopy were assessed. We analyzed 8604 eyes (mean age: 35.6 ± 10.0 years, 837 males, 3465 females). The mean duration of HCL usage was 14.7 ± 9.1 (range, 1-50) years. Multivariate analysis revealed that ECD significantly correlated with age (P < 0.001) but not with duration of usage; however, CV and 6A significantly correlated with both factors (P < 0.001). Univariate analysis revealed that CV and 6A correlated with duration of usage (all, P < 0.001). According to our results, CV and 6A correlated with the duration of HCL usage in ophthalmologically healthy Japanese individuals. Therefore, it is important to monitor corneal endothelial morphology in long-term HCL wearers.

Corneal Tonometric and Morphological Changes in Patients with Acromegaly

(1) Purpose: This study aimed to investigate the changes in Reichert Ocular Response Analyzer (ORA) parameters, corneal endothelium parameters, central corneal thickness (CCT), and intraocular pressure (IOP) before and after the transsphenoidal resection of pituitary adenoma in patients with acromegaly. (2) Methods: This was a single-center, prospective, interventional study. Twenty patients with newly diagnosed acromegaly were examined before and 19 ± 9 months after transsphenoidal resection. The participants underwent a comprehensive ophthalmological examination including pneumatic IOP (IOP air puff), Goldmann applanation tonometry (IOP GAT), CCT measured using the iPac pachymeter (CCT_UP), IOP value corrected for CCT_UP using the Ehlers formula (IOPc) ORA measurements included corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg). CCT from non-contact specular microscopy (CCT_NSM), the number of endothelial cells (CD) per mm2, and average cell size (AVG) were determined with non-contact specular microscopy. (3) Results: A statistically significant decrease was observed in CCT_UP (p = 0.007), and IOP air puff (p = 0.012) after surgery. Moreover, we noted a statistically significant increase in CD (p = 0.001), and a statistically significant decrease in AVG (p = 0.009) and CCT_NSM (p = 0.004) after surgery. A statistically significant decrease was also observed in IOPg (p = 0.011), CH (p = 0.016), and CRF (p = 0.001) after surgery. The mean value of IOP GAT and IOPc was lower after the surgery. However, the difference was not statistically significant. (4) Conclusions: Our study revealed significant changes in biomechanics, corneal endothelium, CCT and IOP after pituitary adenoma resection in patients with acromegaly. It proves that the eye might be sensitive to long-term overexposure to growth hormone (GH) and insulin-like growth factor-1 (IGF-1). We suggest that disease activity be taken into consideration on ophthalmological examination.

Changes in anterior segment parameters and presence of dry eye disease in patients with acromegaly: A Sirius topography study combined with meibography

PURPOSE

To investigate anterior segment parameters (ASPs) and dry eye disease (DED), including the status of the meibomian glands, in patients with acromegaly.

METHODS

In this cross-sectional, comparative study, 36 acromegaly patients and 40 healthy sex- and age-matched controls were included. Participants received a comprehensive ophthalmological examination, including intraocular pressure measurements with Goldmann applanation tonometry (IOP_GAT) and central corneal thickness corrected intraocular pressure (IOP_CCT) measurements, and were evaluated for ASPs and DED. For ASPs, white-to-white (WTW), apical (ACT) and thinnest corneal thickness (TCT), corneal volume (CV), keratometry readings (K₁, K₂, and K_mean), anterior chamber depth (ACD) and volume (ACV), and iridocorneal angle (ICA) were obtained via Sirius topography. DED was assessed with Schirmer's test, tear breakup time (TBUT), and Ocular Surface Disease Index (OSDI) scores. Meibography scores (MSs) were obtained with the Sirius topography device.

RESULTS

Patients had higher mean IOP_GAT (P = .006), IOP_CCT (P = .01), ACT (P = .024), and TCT (P = .005) but narrower ICA (P = .014) than controls. Although Schirmer's test did not differ between the groups (P = .442), patients had higher OSDI (P < .001), higher MS (P = .001), and shorter TBUT (P = .002).

CONCLUSION

Patients with acromegaly have greater IOP, greater corneal thickness, but narrower ICA than healthy individuals, as well as DED with increased MSs, which suggests meibomian gland dysfunction.

Lacrimal gland enlargement and tear film changes in acromegaly patients: A controlled study

PURPOSE

Evaluation of the lacrimal gland volume (LGV) and its correlation with tear film functions, serum growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels in acromegaly patients compared to a control group was aimed.

METHODS

This prospective case-control study included the eyes of 38 patients with uncontrolled (UA) and 48 patients with controlled acromegaly (CA) and 44 patients with nonfunctioning pituitary adenoma. LGV of the patients was evaluated at the baseline, 3rd, and 6th-month visits with magnetic resonance imaging. Schirmer's test, tear breakup time (TBUT), and ocular surface disease index (OSDI) scores were evaluated at the same visits. Their correlation with serum IGF-1 and GH was investigated. Main outcome measure was the difference in mean LGV.

RESULTS

The mean LGV of the acromegaly patients at the baseline visit (116.0 ± 33.2 mm³) and the 3rd-month visit (119.5 ± 36.4 mm³) was higher than the control group (65.2 ± 22.3 mm³ and 63.2 ± 22.3 mm³, respectively; p < 0.001) without any significant difference between the UA and CA patients in the LGV in three consecutive visits (p > 0.05). Among all patients, IGF-1 and GH levels showed a positive correlation with the LGV (p < 0.001; r = 0.52; r = 0.6, respectively). However, Schirmer, TBUT, and OSDI scores did not show any difference among the three groups at each visit (p > 0.05).

CONCLUSION

Acromegaly patients may have larger lacrimal glands compared to the controls and this increase correlated with the increased IGF-1 and GH levels. Lacrimal gland volume may have no effect on its tear film related functions.

Non-contact specular microscopy with Topcon instruments to assess central corneal thickness of healthy human eyes - A 20 year review

BACKGROUND

The purpose of this review was to evaluate the consistency of central corneal thickness (CCT) values reported with use of Topcon SP-2000 P and SP-3000 P non-contact specular microscopes since their introduction in 1999 with the two microscopes having been commonly used in a wide range of studies.

METHODS

As a primary resource, PubMed was used to search for peer-reviewed articles in any language that included CCT values obtained with non-contact specular microscopy reported for humans with nominally healthy corneas. Relevant articles were obtained and any cited publications also checked.

RESULTS

A total of 76 articles were identified which reported CCT on different small-to-moderate sized groups of individuals, published between 1999 and 2019. From these, an overall group mean CCT value of 0.525 ± 0.013 mm (median 0.525 mm) can be calculated. An estimated 95 % confidence interval (CI, based on 1.96 SD) would be between 0.500 and 0.550 mm. For the two Topcon models, the group mean ± SD values were 0.529 ± 0.013 mm and 0.517 ± 010 mm respectively. An assessment of the CCT data sets in relation to the reported average age indicated no statistically significant effect (p = 0.289, r = -0.129). Very similar average CCT values were also encountered in 4 other reports where these microscopes were used in large-scale population studies as well as in 2 other reports using the newer Topcon SP-1 P model.

CONCLUSIONS

The Topcon stand-alone non-contact specular microscopes have yielded consistent and predictable corneal thickness measures over many years.

A fully automated cell segmentation and morphometric parameter system for quantifying corneal endothelial cell morphology

BACKGROUND AND OBJECTIVE

Corneal endothelial cell abnormalities may be associated with a number of corneal and systemic diseases. Damage to the endothelial cells can significantly affect corneal transparency by altering hydration of the corneal stroma, which can lead to irreversible endothelial cell pathology requiring corneal transplantation. To date, quantitative analysis of endothelial cell abnormalities has been manually performed by ophthalmologists using time consuming and highly subjective semi-automatic tools, which require an operator interaction. We developed and applied a fully-automated and real-time system, termed the Corneal Endothelium Analysis System (CEAS) for the segmentation and computation of endothelial cells in images of the human cornea obtained by in vivo corneal confocal microscopy.

METHODS

First, a Fast Fourier Transform (FFT) Band-pass filter is applied to reduce noise and enhance the image quality to make the cells more visible. Secondly, endothelial cell boundaries are detected using watershed transformations and Voronoi tessellations to accurately quantify the morphological parameters of the human corneal endothelial cells. The performance of the automated segmentation system was tested against manually traced ground-truth images based on a database consisting of 40 corneal confocal endothelial cell images in terms of segmentation accuracy and obtained clinical features. In addition, the robustness and efficiency of the proposed CEAS system were compared with manually obtained cell densities using a separate database of 40 images from controls (n = 11), obese subjects (n = 16) and patients with diabetes (n = 13).

RESULTS

The Pearson correlation coefficient between automated and manual endothelial cell densities is 0.9 (p < 0.0001) and a Bland-Altman plot shows that 95% of the data are between the 2SD agreement lines.

CONCLUSIONS

We demonstrate the effectiveness and robustness of the CEAS system, and the possibility of utilizing it in a real world clinical setting to enable rapid diagnosis and for patient follow-up, with an execution time of only 6 seconds per image.

Auditory changes in acromegaly

OBJECTIVE

The aim of this study is to determine the changes involving auditory system in cases with acromegaly.

MATERIALS AND METHODS

Otological examinations of 41 cases with acromegaly (uncontrolled n = 22, controlled n = 19) were compared with those of age and gender-matched 24 healthy subjects. Whereas the cases with acromegaly underwent examination with pure tone audiometry (PTA), speech audiometry for speech discrimination (SD), tympanometry, stapedius reflex evaluation and otoacoustic emission tests, the control group did only have otological examination and PTA. Additionally, previously performed paranasal sinus-computed tomography of all cases with acromegaly and control subjects were obtained to measure the length of internal acoustic canal (IAC).

RESULTS

PTA values were higher (p < 0.001 for right ears and p = 0.001 for left ears), and SD scores were (p = 0.002 for right ears and p = 0.002 for left ears) lower in acromegalic patients. IAC width in acromegaly group was narrower compared to that in control group (p = 0.03 for right ears and p = 0.02 for left ears). When only cases with acromegaly were taken into consideration, PTA values in left ears had positive correlation with growth hormone and insulin-like growth factor-1 levels (r = 0.4, p = 0.02 and r = 0.3, p = 0.03). Of all cases with acromegaly 13 (32%) had hearing loss in at least one ear, 7 (54%) had sensorineural type and 6 (46%) had conductive type hearing loss.

CONCLUSION

Acromegaly may cause certain changes in the auditory system in cases with acromegaly. The changes in the auditory system may be multifactorial causing both conductive and sensorioneural defects.

Effects of Laser Peripheral Iridotomy on Corneal Endothelial Cell Density and Cell Morphology in Primary Angle Closure Suspect Subjects

Purpose:

To evaluate the effects of prophylactic laser peripheral iridotomy on corneal endothelial cell density and cell morphology in subjects with primary angle closure suspect (PACS) within a one-year follow-up period.

Methods:

In this quasi-experimental prospective study, from June 2012 to November 2013, thirty-five PACS eyes underwent laser peripheral iridotomy at clinics affiliated to Shiraz University of Medical Sciences, Shiraz, Iran. After obtaining informed consent, specular microscopy was performed at baseline and at 3-month, 6-month and 12-month follow-up visits. Central, nasal and temporal endothelial cell counts and cell morphology were evaluated via non-contact specular microscopy.

Results:

The mean subject age was 53.4 ± 7.9 years, and the majority of subjects were women (88.2%). The mean central corneal endothelial cell count prior to laser peripheral iridotomy was 2528 ± 119.2, and this value changed to 2470 ± 175.9, 2425 ± 150.6, and 2407 ± 69.02 at the 3-month, 6-month, and 12-month follow-up visits, respectively; these differences did not reach statistical significance. Additionally, the changes in the number of cells, the hexagonality of cells, and the coefficient of variation (CV) in the central, nasal, and temporal areas were not significant.

Conclusion:

In PACS eyes, we did not find a decline in corneal endothelial cell density or a change in cell morphological characteristics, including cell hexagonality and CV, in the central, nasal, and temporal regions of the cornea in any of our subjects over a one-year follow-up period.