ABSTRACT
BACKGROUND: The aim was to evaluate the correlation between the anatomical and functional outcomes before and after treatment of uveitic macular oedema. METHODS: Thirty-three eyes of 33 patients with uveitic macular oedema were included in the present study. Visual acuity (VA), optical coherence tomography (OCT) and multifocal electroretinogram (mfERG) were measured before and after treatment of the macular oedema. Correlation analyses between VA, OCT and mfERG parameters were performed. RESULTS: The VA and mfERG measurements showed statistically significant improvement after treatment of the macular oedema (p < 0.01) and OCT-measured central foveal thickness decreased significantly from 434 ± 135 µm before treatment to 267 ± 92 µm after treatment (p < 0.001). Correlation analyses showed that uveitic central foveal thickness before treatment was correlated with mfERG N1 response amplitude of area 1 (Spearman's r = -0.62, p < 0.001). VA (logMAR) after treatment had a negative correlation with the mfERG N1 response amplitude of area 1 (Spearman's r = -0.56, p = 0.001). Also, there was no correlation between the final VA and pre-treatment OCT and mfERG measurements. CONCLUSION: This study deals with cystoid macular oedema associated with recurrent uveitis. In cystoid macular oedema, the value of mfERG before treatment is related to the central foveal thickness and VA. In contrast, after treatment the decrease of macular thickness is not always followed by an improvement of mfERG and VA. This supports the view that in uveitic macular oedema, the decrease in macular thickness after treatment may not be used as a predictor of improvement of macular function.
Subject(s)
Electroretinography/methods , Fovea Centralis/pathology , Glucocorticoids/administration & dosage , Immunosuppressive Agents/administration & dosage , Macular Edema/diagnosis , Tomography, Optical Coherence/methods , Uveitis/complications , Adult , Aged , Diagnosis, Differential , Drug Administration Routes , Drug Therapy, Combination , Female , Follow-Up Studies , Fovea Centralis/physiopathology , Humans , Macular Edema/drug therapy , Macular Edema/etiology , Male , Middle Aged , Prospective Studies , Reproducibility of Results , Treatment Outcome , Uveitis/diagnosis , Uveitis/drug therapy , Visual AcuityABSTRACT
BACKGROUND: To evaluate the relationship between hypobaric hypoxia acclimatization and intraocular pressure (IOP) during ascent, acclimatization, and descent between 2286 m and 5050 m. METHODS: The following acclimatization-indicative physiological parameters were compared daily with IOP changes in eight healthy climbers of the 2003 Greek Karakorum expedition in altitude stages between 500 m and 5050 m: hemoglobin oxygen saturation (PO2), resting heart rate, blood pressure, retinal findings, and the Lake Louise score for acclimatization grading. RESULTS: IOP decreased significantly in the ascent phase (0.58 mmHg/100 m) and recovered (0.71 mmHg/100 m) during acclimatization and descent. A direct proportional correlation between decreases in PO2 and IOP was evaluated. Arterial blood pulse and pressure increased during acclimatization, while IOP decreased. No retinal hemorrhages were observed in well-acclimatized and incompletely acclimatized climbers. CONCLUSIONS: Every new active exposure to hypobaric hypoxia in the ascent phase induced a decrease in the IOP parallel to the PO2 decrease and to the level of acclimatization. The results from our study suggest that IOP changes are related to hypoxia-induced respiratory alkalosis and acclimatization stage, which could be used as a simple mobile screening test for acclimatization level to reveal acute mountain sickness and its severe consequences.
Subject(s)
Acclimatization/physiology , Alkalosis, Respiratory/physiopathology , Altitude , Hypoxia/physiopathology , Intraocular Pressure/physiology , Adult , Aged , Altitude Sickness/diagnosis , Atmospheric Pressure , Blood Pressure/physiology , Female , Heart Rate/physiology , Humans , Male , Middle Aged , Partial PressureABSTRACT
BACKGROUND: To evaluate the short- and long-term effects of high-altitude hypobaric hypoxia on macula morphology and function during ascents, acclimatizations, and descents between 500 m and 5,650 m, macula function was evaluated in three healthy climbers of a trekking expedition. METHODS: Macula physiology was tested with multifocal electroretinography (MF ERG), near and farvisual acuity, and Amsler grid tests. Macula morphology was tested with optical coherence tomography (OCT) and with stereoscopic fundoscopy obtained 1 week before ascent, as well as 1 week and 2 weeks after high-altitude exposure. The following physiological parameters indicative of acclimatization were compared daily during the expedition at altitudes between 500 m and 5,050 m: hemoglobin, oxygen saturation, resting heart rate, retinal findings, and the Lake Louise score of acclimatization. RESULTS: The central macula MF ERG responses were significantly reduced 1 week after high-altitude exposure, and had recovered by the follow-up examination performed during the following week. Near visual acuity and Amsler grid tests remained unaffected at both follow-up examinations. No significant changes were found in the follow-up OCT and daily fundoscopy examinations in all three well-acclimatized climbers. CONCLUSIONS: High-altitude hypobaric hypoxia affects the function of the highly sensitive macula region. This suggests that the exposure of persons with macula diseases such as age-related macula degeneration, tapetoretinal degeneration, or diabetic retinopathy to high altitudes may influence the disease progression. For this reason, this population should avoid prolonged and unnecessary high-altitude exposure without proper acclimatization.
