The evaluation of central corneal thickness and intraocular pressure in conjunction with tear IGF-1 levels in patients with acromegaly

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.

Elevated IGF-1 and GH Levels Are Correlated With a Thicker Iris and Wider Anterior Chamber Angle in Treatment-Naïve Acromegaly Patients

Purpose

To compare the difference in anterior segment biometrics derived from anterior segment optical coherence tomography (AS-OCT) between treatment-naïve acromegaly patients and normal controls and evaluate the correlations between above biometrics and insulin-like growth factor 1 (IGF-1) and growth hormone (GH) levels.

Methods

Sixty eyes of 30 acromegaly patients and 60 eyes of 30 normal controls were included in this case-control study. Central corneal thickness, pupil diameter, iris thickness (IT), iris curvature (IC), anterior chamber depth (ACD), anterior chamber width, lens vault (LV), angle open distance (AOD) 500, AOD750, and trabecular iris space area (TISA) 500 and TISA750 were measured by AS-OCT. General linear regression models were constructed to evaluate the independent endocrine factors affecting iris morphology and anterior chamber angle (ACA) width.

Results

The acromegaly patients had an evenly thicker iris (P < 0.001), a smaller IC (P < 0.05), a smaller LV (P = 0.040) and significantly larger AOD500, AOD750, TISA500 and TISA750 (P < 0.001). There was a positive correlation between the serum GH level and ACD in the acromegaly patients (P = 0.031). Linear regression models showed the lower LV and smaller IC were independent influencing factors of the increase in the AOD500, AOD750, and TISA750 and nasal TISA500. Serum IGF-1 was an independent factor for the increase in pupil diameter (β = 0.002, P = 0.031) and both the average nasal (β = 6.781*10⁻⁵, P = 0.049) and temporal (β = 7.736*10⁻⁵, P = 0.045) IT values and for the decrease in temporal IC (β < 0.001, P = 0.037). GH was an independent factor for the increase in temporal AOD750 (β = 0.001, P = 0.030) and temporal TISA750 (β = 0.002, P = 0.016).

Conclusions

Patients with acromegaly have a thicker IT, smaller IC, and lower LV with a wider ACA than normal controls. Serum GH is independently correlated with the temporal ACA width, whereas serum IGF-1 is independently correlated with IT, pupil diameter, and IC.

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.