Basal Secretion Test Research Articles

Ocular Surface Changes in Primary Open Angle Glaucoma Patients Treated With Topical Antihypertensive Drugs.

In this study, patients with glaucoma undergoing topical antihypertensive (TAH) drugs had changes in the ocular surface and more dry eye symptoms than controls. Clinicians should recognize the influence of TAH drops on exacerbating ocular surface disease. The purpose of this study was to evaluate the ocular surface of eyes with glaucoma treated with TAH drugs. Cross-sectional study that included eyes undergoing TAH drugs due to primary open angle glaucoma and controls. The parameters evaluated were: the basal tear flow (basic secretion test); the tear film osmolarity (TearLab); and the noninvasive break-up time, blink score, lipid layer thickness, tear meniscus height, and loss area of the meibomian glands, measured with the IDRA Ocular Surface Analyser. Presence of symptoms [Ocular Surface Disease Index (OSDI)], dry eye disease (DED, TFOS DEWS II criteria), and corneal fluorescein staining were assessed. We included 154 eyes (154 patients), 77 undergoing TAH drugs for glaucoma (group 1) and 77 of controls (group 2). The tear film osmolarity ( P =0.003) and the loss area of the meibomian glands ( P =0.004) were higher in group 1. The noninvasive break-up time ( P =0.005), lipid layer thickness ( P =0.006), and tear meniscus height ( P =0.001) were lower in group 1. The global OSDI score ( P <0.001), the proportion of eyes with severe disease ( P =0.002), according to the OSDI, and with DED ( P <0.001), according to the TFOS DEWS II criteria, were higher in group 1. The proportion of patients with corneal fluorescein staining was higher in group 1 ( P <0.001). There were no significant differences in eyes taking TAH drugs with and without preservatives ( P >0.127). DED, in patients with glaucoma, is a multifactorial disease, with a strong contribution from TAH drugs. These eyes had changes in almost every measured parameter, translating into the presence of more dry eye symptoms and corneal damage when compared with controls.

Optical Coherence Tomography Angiography for Evaluation of Conjunctival Vessels in Dry Eyes.

This study aimed to evaluate conjunctival vessels in patients with dry eye disease (DED) using optical coherence tomography angiography (OCTA). This was a cross-sectional, observational clinical study. Twenty-three eyes of 18 patients with DED and 28 eyes of 23 healthy controls were included for examination in this study. The evaluation included the application of an Ocular Surface Disease Index Questionnaire, Schirmer Basic Secretion Test, and anterior OCTA targeting the temporal conjunctiva. AngioTool software was used to quantify the total vessel length and vessel density in the 3 × 3 mm temporal region of interest. Blood vessel density measurements were compared across the OCTA systems. The total vessel length within the conjunctiva of the DED group (4799.34 ± 834.36) exceeded that of the control eye (3864.89 ± 1455.70) group (P < 0.05). However, the difference in vessel density between the two groups was not statistically significant. Measurement and analysis of conjunctival blood vessels using OCTA exhibited robust repeatability. In dry eyes, the total number of conjunctival blood vessels increased in accordance with disease severity. Hypoxia of conjunctival tissue may be an important cause of dry eye disease.

Tear film changes after cataract surgery: manual small-incision cataract surgery versus phacoemulsification

Aim The aim was to identify if the type of surgical procedure has any bearing on dry eye syndrome and to find out the duration of postsurgical recovery of dryness in small-incision cataract surgery and phacoemulsification. Patients and methods A prospective randomized study was conducted on 100 patients of cataract. Group A had 50 patients who underwent small-incision cataract surgery, and group B included 50 patients who underwent phacoemulsification. Patients with pre-existing ocular surface disease, for example, known case of glaucoma; taking topical antiglaucoma drugs; lid disorders; and grade 5 cataract (hard cataract in which it is difficult to do phacoemulsification) were excluded. Dry eye workup included Schirmer’s I, basic secretion test, tear film breakup time, and corneal sensation. The workup was done preoperatively and then on seventh, 21st, and 90th day postoperatively. The values were compared in the group itself and in-between the two groups. Results In groups A and B, there was significant difference in the preoperative values of Schirmer’s I test, basic secretion test, and tear breakup time (TBUT) as compared with day 7 and day 21 postoperative values (P 0.05). There was significant difference in the Schirmer’s I test and basic secretion test values after 21 days of surgery between the groups (P 0.05). Conclusion Cataract surgery can cause or aggravate dry eye and affect the dry eye test values in the postoperative period up to 3 months. This holds true for both manual small-incision cataract surgery and phacoemulsification surgery. Therefore before surgery, patients must be informed about the possible aggravation of dry eye symptoms, and artificial tears should be prescribed for attenuating corneal damage and dry eye symptoms.

Dry Eye in Patients With Diabetic Retinopathy: A Clinical Study

Purpose: To study tear film changes in patients of Type 2 diabetes mellitus with and without diabetic retinopathy. Method: A hospital based, cross sectional, observational study including 40 patients of Type 2 diabetes mellitus with diabetic retinopathy and 40 patients without diabetic retinopathy. The parameters evaluated for each patient included a questionnaire (based on McMonnie’s Dry Eye questionnaire), Schirmer’s basic secretion test (BST) and Tear film break up time (TBUT). Results: The prevalence of dry eye in patients without diabetic retinopathy was 5% (Schirmer’s BST) and 42.5% (TBUT) as compared to 21.25% (Schirmer’s BST) and 82.5% (TBUT) in patients with diabetic retinopathy. Schirmer’s BST and TBUT were found decreased with the increase in severity of diabetic retinopathy (p<0.001). Conclusions: The prevalence and severity of dry eye, based on clinical parameters, was more in patients with diabetic retinopathy as compared to those without diabetic retinopathy.

The Changes in Tear Film After Dacryocystorhinostomy

Purpose: This study was performed to evaluate the changes in tear film and ocular surface after dacryocystorhinostomy (DCR) in patients with primary acquired nasolacrimal duct obstruction. Methods: Forty subjects who showed successful results at three months after endoscopic DCR were investigated. The changes in tear breakup time (BUT), basal secretion test (BST), corneal sensitivity test (CST), tear clearance rate (TCR) and keratoepitheliopathy (KEP) were evaluated. Results: The mean age was 57.413.2 years (2977 years). Preoperative BST and BUT in eyes which underwent DCR were 13.213.79 mm and 8.202.30 seconds, respectively. Three months after the operation, the respective values were 9.133.77 mm (p=0.01) and 6.272.20 seconds (p=0.03). Preoperative CST, TCR and KEP in eyes which underwent DCR were 57.894.18 mm, 3.260.91 and 0.120.53, respectively. Three months after the operation, the respective values were 57.753.55 mm (p=0.32), 3.040.87 (p=0.08) and 0.130.54 (p=0.08). No changes were observed between the preoperative and postoperative tear parameters in fellow eyes. Conclusions: The changes in tear film parameters including BST and BUT should be considered in patients who receive endoscopic DCR.

Prevalence of Dry Eye at High Altitude: A Case Controlled Comparative Study

High altitude is associated with physiological as well as pathological changes in the eye related to adverse environmental conditions that result in increased tear evaporation and contribute to a higher incidence of dry eye in these regions. We aimed to study the difference in prevalence of dry eye at high altitude and at low altitude. The prevalence of dry eye among the natives and the army soldiers who were recently posted at high altitude was also studied and compared. 200 adults above 20 years of age were enrolled. 100 subjects were recruited at a high altitude region (study group), of which 50 were native Ladakhis and 50 were soldiers recently posted at Leh, Ladakh, India (height; 3300 m above sea level; temperature: 18 degrees C to 24 degrees C). 100 subjects, age and sex matched, were screened at a low altitude region, New Delhi, India (218 m above sea level; temperature: 19 degrees C to 24 degrees C) to serve as the control group. Prevalence of dry eye was assessed through standard questionnaires (McMonnies' Questionnaire (MMI), Ocular Surface Disease Index Questionnaire (OSDI), and Schirmer's basic secretion test. On the basis of the parameters studied (symptoms, MMI, OSDI and Schirmer's test), dry eye was diagnosed in 20% of subjects screened at high altitude and in 9% of subjects in the control group screened at low altitude. In the study group, the prevalence of dry eye was significantly higher amongst the native population (54%) than in the army soldiers who were recently posted at that region (26%). The difference was statistically significant (p<0.005). In conclusion, dry eye is more common at high altitude, particularly in the native population. Awareness among people residing at high altitude and the treating medical personnel needs to be created for early detection and treatment of dry eye to prevent vision-threatening complications.

High‐order aberrations and preoperative associated factors

The purpose of this study was to determine which preoperative factors are associated with the presence of high-order aberrations. A total of 93 eyes of 52 subjects were evaluated preoperatively between 1 January and 31 March 2003, using a Hartmann-Shack-based aberrometer. Age, gender, cycloplegic refraction, pupil size, keratometry readings, anterior chamber depth, white-to-white tests, intraocular pressure and basic secretion tests were evaluated. Factors associated with high-order aberrations included age > or = 40 years (mean 4.39 +/- 2.95 microm; p = 0.03, Mann-Whitney test), higher keratometry values (44.96 +/- 1.57 D) (r = 0.447, p < 0.001, Spearman's correlation coefficient), higher degrees of myopia (> or = - 6.1 D) (p < 0.001, Kruskall-Wallis test) and increasing pupil size (p < 0.001, anova). Other factors including anterior chamber depth, white-to-white results, intraocular pressure and basic secretion test results did not correlate with the presence of high-order aberrations preoperatively. Ocular wavefront aberrations varied greatly from subject to subject. Treatment should be customized for each laser based on patient characteristics in order to ensure the optimal treatment profile for the aberration.

Effect of hinge location on corneal sensation and dry eye after laser in situ keratomileusis for myopia

To evaluate the effects of a superior or nasal hinge location on corneal sensation and dry eye after laser in situ keratomileusis (LASIK). Magill Research Center for Vision Correction, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. This prospective randomized masked study included 47 patients having bilateral myopic LASIK surgery. The first eye was randomly assigned to have a nasal or superior hinge flap; the fellow eye had the alternate location. Visual acuity, contrast sensitivity, corneal sensation, basic secretion test, tear film breakup time, conjunctival and corneal staining, and a subjective questionnaire were evaluated preoperatively and postoperatively at 1 week and 1, 3, and 6 months. The Wilcoxon signed rank test and paired t test were used for comparison. Dry eye occurred with the same frequency in both groups. However, eyes with the nasal hinge had significantly better nasal sensation than those with the superior hinge (P<.05) at 1 month. Better nasal corneal sensation was found at 1 month in the nasal hinge group but there was no difference in any other parameters measured.

Onset and Pattern of Tear Secretions in Full-Term Neonates

Purpose: Serial evaluations of total, basal and emotional tear secretion in full-term normal neonates to determine the time after birth when these parameters attain normal adult values. Method: Both eyes of 102 full-term normal neonates were prospectively evaluated for tear secretions in the Department of Ophthalmology, over a period of one year. Serial recording of the Schirmer I test (total tear secretions), Basal Secretion Test, and Schirmer II test (emotional tears) was done, the first one being within 6 hours of birth. All the tests were repeated in each infant until normal adult values for each test were obtained. Results: The average values of the Schirmer I test, Basal Secretion Test and Schirmer II test at birth were 23.2 (± 3.96) mm, 6.2 (±2.15) mm and 19.2 (±4.94) mm, respectively. A statistically significant correlation of birth weight but not of gestational age was found with basal secretions (p = 0.004) as well as with emotional tears (Schirmer II test, p = 0.010). At birth, 98% of infants had total tear secretion, 3.9% had basal tear secretion and 2.9% had emotional tear secretion comparable to normal adult values. All the parameters of tear secretions increased with time, so that 100% of infants had total tear secretion comparable to normal adult values within 12 hours of birth. The basal secretions took three weeks and emotional tears took four weeks to attain normal adult values in all the neonates. Conclusion: Total tear secretions were the earliest to reach normal adult values, followed by basal secretions and, lastly, emotional tears. Reduced basal tears at birth may predispose neonates to corneal drying during prolonged ocular examinations such as indirect ophthalmoscopy and procedures under general anesthesia.

Ocular discomfort and conjunctival alterations in operating room workers. A single-institution pilot study.

The aim of this pilot study was to relate the eye symptoms complained of by subjects working in the operating rooms of a hospital in southern Italy, with the observations of alterations of the ocular surface. An epidemiological study was carried out by a questionnaire aimed at investigating the prevalence of ocular discomfort symptoms among 213 subjects working in operating rooms and 40 subjects working in the wards. The investigated symptoms were the following: tiredness, heaviness, burning, redness, tearing, itching, blinking, foreign body sensation, and photophobia. A randomised comparative study of the ocular surface and conjunctival cytology was also carried out, comparing two groups of age- and gender-matched subjects. Group 1 included 24 subjects randomly chosen from the operating room workers with ocular discomfort symptoms; group 2 included ten subjects randomly enrolled from hospital personnel working in the wards. Ophthalmological examination of the ocular surface was performed on each subject in the following order: slit-lamp examination, break-up time (BUT) of the pre-corneal tear film, corneal fluorescein stain, lachrymal basal secretion test, conjunctival impression cytology. A high prevalence (72.3%) of ocular discomfort symptoms was reported by operating room workers, while in ward personnel the prevalence was 55% (P = 0.04). The ocular tests showed that the conjunctival features and BUT were statistically significantly altered in subjects in group 1. Also, the conjunctival impression cytology study showed statistically significant alterations of all the investigated parameters: specimen cellularity, cell-to-cell contacts, nucleus/cytoplasm ratio, chromatin pattern, goblet cell distribution, keratinisation and the total cytological score. Our results show that self-reported eye complaints and ocular surface alterations have a high prevalence in subjects working in the operating rooms. This seems to indicate that the operating room environment could play a role in the onset of the eye disturbances.

Oxidative reactions in the tear fluid of patients suffering from dry eyes.

To evaluate whether products of oxidative and inflammatory reactions are detectable in the tear fluid of patients suffering from dry eyes. The tear fluid of 217 patients (397 eyes) was sampled. Criteria for grouping of the patients were (1) basic secretion test ("sicca 1": BST = 0-5 mm, n = 78 eyes; "sicca 2": BST = 6-10 mm, n = 109 eyes) and (2) subjective symptoms (normal BST, burning, foreign body sensations, tearing, dryness of the eyes: n = 78 eyes). One group of healthy patients (normal BST, n = 132 eyes) served as controls. Lipid peroxide levels and myeloperoxidase activity, as parameters for oxidative tissue damage and inflammatory activity, were determined in the tear fluid. Those patients whose consent could be obtained were subjected to the rose bengal test (sicca 1: 56 eyes; sicca 2: 97 eyes; subjective symptoms: 44 eyes; controls: 49 eyes). The correlation between BST and rose bengal test results was calculated. Lipid peroxides were significantly (P < 0.05) higher in the groups sicca 1 and subjective symptoms than in healthy controls, as was the inflammatory activity in groups sicca 1, sicca 2 and subjective symptoms. Additionally, the inflammatory activity in the group sicca 1 was significantly (P < 0.05) higher than in the groups sicca 2 and subjective symptoms. No evidence of a significant correlation between BST and rose bengal test results was observed. Both oxidative tissue damage and polymorphonuclear leukocytes indicating an oxidative potential occur in the tear film of patients suffering from dry eyes. These reactions lead to severe damage of the involved tissue. Free radicals and inflammation may be involved in the pathogenesis or in the self-propagation of the disease.

Duration of antisecretory effects of oral omeprazole in horses with chronic gastric cannulae

SummaryEight female horses with chronic gastric cannulae were given omeprazole as enteric‐coated granules (1.4 mg/kg bwt) via nasogastric tube once daily for 6 days. The effects on basal and pentagastrin‐stimulated gastric acid secretion were determined 5 h after dosing on Days 1 and 5 ofadministration. A third gastric secretion test was done on Day 7, 24 h after the dose on Day 6. Gastric juice volume, pH, acidity, and acid output were determined during a 1‐h basal secretion test followed by a 2‐h pentagastrin‐stimulated (6 μg kg−1 h−1) test.When compared with placebo controls, omeprazole significantly inhibited basal gastric acid output by 72% and pentagastrin‐stimulated acid output by 86% on Day 5. Gastric juice pH was also significantly increased. On Day 7, basal gastric acid output was significantly decreased by 90% and pentagastrin‐stimulated secretion was decreased by 72%. The effect of omeprazole administration on gastric juice volume was variable.Once daily administration of 1.4 mg omeprazole/kg bwt significantly inhibited basal and stimulated gastric acid secretion in horses by the 5th dose. Gastric acid secretion was significantly inhibited for at least 27 h after omeprazole treatment, indicating a long duration of antisecretory effect of the drug in horses.

Effect of eledoisin on tear volume and tear flow in humans as assessed by fluorophotometry

Topical application of the endekapeptide eledoisin has been reported to increase tear secretion in patients with dry eye. However, to date the efficacy of eledoisin has been proved only by methods that are not easily reproduced and have an enormous intraindividual scatter range (Schirmer test, basic secretion test). In the present study the effect of topically applied eledoisin on tear volume and tear flow was determined quantitatively by means of objective fluorophotometry in 40 subjects, 20 of whom suffered from severe dry eyes. Both tear volume and tear flow were found to be significantly increased up to 2 h after instillation, reaching a maximum 1 h after application (tear volume: +87% and +35% for dry eyes and healthy controls, respectively; tear flow: +250% and +27% for dry eyes and healthy controls, respectively).

Increased tear evaporation in eyes with keratoconjunctivitis sicca.

The terms dry eye and keratoconjunctivitis sicca (KCS) imply a condition of highly reduced or absent tear film that often is not clinically demonstrable despite the presence of other signs and symptoms. In 52 patients with KCS symptoms, either with or without tear volume reduction as measured by Schirmer's basic secretion test, we found a statistically significant increase in water evaporation rate from the tear film when compared with normal subjects. Such an increased evaporation rate might account for the tear hypertonicity known to be associated with KCS and postulated to be responsible for ocular surface damage. Thus, we propose to identify this group of paradoxically wet "dry eyes" as a "syndrome of increased tear evaporation", which better describes the pathogenesis of the ocular condition.