Subclinical damage to the contralateral eye in unilateral optic neuritis: A longitudinal study.

BACKGROUND: Early detection of subclinical injuries can lead to a correct diagnosis and help control the advancement of the condition. This study aims to investigate the presence of subclinical damage and silent progression to the contralateral eye's visual function and structure in patients experiencing their first episode of unilateral optic neuritis (ON). METHODS: Fifty patients with first-onset unilateral ON were enrolled in this study. Based on etiology, they were classified as having neuromyelitis optica spectrum disorder-related ON (NMOSD-ON), myelin oligodendrocyte glycoprotein antibody-associated ON (MOG-ON), idiopathic ON (IDON), or multiple sclerosis-related ON (MS-ON). These cases were followed up for one year to determine whether there was any silent progression of visual function and structure in the contralateral non-ON (NON) eye. A gender- and age-matched healthy control (HC) group was included to compare the differences in visual function and structure between the patients with NON eyes and the HC group. RESULTS: Within two weeks of onset, best-corrected visual acuity (BCVA; P = 0.008), mean deviation (MD) of the visual field (VF) (P = 0.001), and peripapillary retinal nerve fiber layer (pRNFL; P = 0.019) thickness were significantly worse in the NMOSD-NON patients than those in the HC group, while there were no differences in the pRNFL and the ganglion cell-inner plexiform layer (GCIPL) thicknesses and quadrant thicknesses (P > 0.05) of the groups. IDON-NON only showed subclinical damage in VF (P = 0.001) and temporal pRNFL (P = 0.042), while the BCVA, VF, and optic nerve structure (pRNFL, GCIPL) of the MOG-NON patients showed no subclinical damage (P > 0.05). In addition, the one-year follow-up of each NON eye type showed that there was no silent progression in NMOSD-NON, MOG-NON, or IDON-NON. A pairwise comparison of the different types of NON eyes revealed no statistical differences (P > 0.05). CONCLUSION: Among the patients with unilateral ON, NMOSD-NON and IDON-NON resulted in subclinical damage to the visual function and structure of the contralateral eye within two weeks of onset, whereas MOG-NON did not show any subclinical damage to visual function or structure. Furthermore, these subclinical damages did not show any silent progression during the one-year follow-up period.

Influence of obstructive sleep apnea syndrome on the contralateral optic nerve in patients with unilateral nonarteritic anterior ischemic optic neuropathy.

STUDY OBJECTIVES: The aim was to quantitatively evaluate the influence of obstructive sleep apnea syndrome (OSAS) on the morphology and function of the contralateral optic nerve in patients with unilateral nonarteritic anterior ischemic optic neuropathy (NAION). METHODS: Fifty patients with unilateral NAION were divided into non-OSAS (n = 16), mild OSAS (n = 15), and moderate-severe OSAS (n = 19) groups based on their apnea-hypopnea index (AHI) scores. Systemic and ocular characteristics were compared between these groups. Spearman correlation and multiple linear regression analyses were used to determine the independent factors that most influenced the thickness of the peripapillary retinal nerve fiber layer (pRNFL). RESULTS: Body mass index and hypertension occurrence were higher in the moderate-severe OSAS group than in the non-OSAS group. Temporal pRNFL was thinner in the moderate-severe group than in the mild and non-OSAS groups, whereas no difference was found between the mild and non-OSAS groups. Spearman correlation showed that the AHI (r = -.469, P = .001) and the percentage of total sleep time with oxygen saturation < 90% (T90%; r = -.477, P = .001) correlated with temporal pRNFL thickness. Multiple linear regression showed that the AHI was negatively associated with temporal pRNFL thickness (ß = -0.573, P = .003). CONCLUSIONS: OSAS may cause subclinical temporal pRNFL thinning in the contralateral optic nerve among patients with unilateral NAION without any significant change in visual function. Advanced optic nerve observation and intervention may be warranted in patients with moderate-severe OSAS. CITATION: Li X, Zhang Y, Guo T, et al. Influence of obstructive sleep apnea syndrome on the contralateral optic nerve in patients with unilateral nonarteritic anterior ischemic optic neuropathy. J Clin Sleep Med. 2023;19(2):347-353.

Risk Factors for Fellow Eye Involvement in Patients with Nonarteritic Anterior Ischemic Optic Neuropathy.

INTRODUCTION: To investigate the possible risk factors for fellow eye involvement in patients with nonarteritic anterior ischemic optic neuropathy (NAION). METHODS: A total of 113 patients with unilateral NAION attack were included and divided into two groups according to whether fellow eye involvement was present over a mean follow-up period of 2.70 years (P25-P75: 0.77-3.54 years). General characteristics (including age, sex, diabetes, hypertension, hyperlipidemia and obstructive sleep apnea syndrome) and ocular characteristics (including initial best corrected visual acuity, initial visual field damage of the first eye and the presence/absence of a crowded disc) were analyzed and compared between the two groups. Cox regression was used to assess the risk factors for fellow eye involvement. RESULTS: During the follow-up period, 40 patients developed fellow eye involvement. The initial best corrected visual acuity (P = 0.048) and mean deviation (MD) of the visual field (VF) (P = 0.039) of the first eye in patients with fellow eye involvement were worse than those in patients without it. Diabetes (HR = 3.06, 95% CI: 1. 50, 6.26, P = 0.002) and increased VF damage (moderate vs. mild, HR = 2.92, 95% CI: 1.03, 8.25, P = 0.043; severe vs. mild, HR = 5.01, 95% CI: 1.65, 15.20, P = 0.004) were associated with a significantly increased risk of fellow eye involvement. In 57 patients with apnea hypopnea index (AHI) data for further study, an AHI score≥ 23.2 was also found to be a risk factor (HR = 3.36, 95% CI: 1.17, 9.69, P = 0.025). CONCLUSION: Diabetes, severer initial VF damage, and more severe obstructive sleep apnea syndrome (OSAS) were risk factors for fellow eye involvement in NAION. For patients with these risk factors, more intensive follow-ups might be warranted.

[Analysis of the function of diaphragm and its influencing factors in mechanical ventilation patients by using fully automatic trigger twitch tracheal pressure].

OBJECTIVE: To understand the function of diaphragm and analyze the clinical factors affecting the function of diaphragm by measuring twitch tracheal pressure (TwPtr) in patients with mechanical ventilation and in the weaning phase. METHODS: Patients with more than 48 hours of invasive mechanical ventilation admitted to the department of critical care medicine of the First Affiliated Hospital of Guangzhou Medical University from December 2015 to March 2017 were enrolled. After the patient entered the weaning stage, TwPtr of patients was monitored by two-way non repetitive automatic respiratory trigger device, the effects of duration of mechanical ventilation, severe pulmonary infection, sedative application and chronic obstructive pulmonary disease (COPD) on weaning were analyzed. RESULTS: A total of 62 patients were included, of which 45 were male and 17 were female. The average age was (66.8±11.7) years old. Twenty-three cases had severe pneumonia. The absolute value of TwPtr in severe pneumonia group was lower than that in non-severe pneumonia group [cmH2O (1 cmH2O = 0.098 kPa): 10.40±5.81 vs. 14.35±5.22, P = 0.021]. However, there was no significant difference in the duration of mechanical ventilation between the severe pneumonia group and non-severe pneumonia group [days: 26 (17, 43) vs. 15 (11, 36), P = 0.091]. In 62 patients with mechanical ventilation, there was a negative correlation between TwPtr and duration of mechanical ventilation (r = 0.414, P = 0.002), there was also a negative correlation between the duration of mechanical ventilation and TwPtr after the assessment of diaphragm function (r = 0.277, P = 0.039). There was a linear relationship between TwPtr and sedatives (r = 0.220, P = 0.040), but there was no correlation between TwPtr and COPD (r = -0.178, P = 0.166). CONCLUSIONS: For patients in the weaning stage of mechanical ventilation, severe pulmonary infection is one of the factors that affect the diaphragm dysfunction. There is a certain correlation between the diaphragm dysfunction and the use of sedatives.