Intraocular pressure according to different types of tonometry (non-contact and Goldmann applanation) in patients with different degrees of bilateral tearing

Abstract

PurposeTo investigate intraocular pressure (IOP) readings by non-contact tonometry (NCT) and Goldmann applanation tonometry (GAT) for patients with different degrees of bilateral tearing.MethodsIn this study, we reviewed the medical charts of patients complaining of different degrees of bilateral tearing. The tear meniscus height (TMH) and IOP with NCT and GAT were measured. In each patient, a comparison of IOP readings between the eye with lower TMH and the contralateral eye with higher TMH was evaluated. The TMH was graded as follows: grade 1 (low): TMH < 0.2 mm; grade 2 (moderate): 0.2 mm ≤ TMH < 0.6 mm; grade 3 (high): TMH ≥ 0.6 mm. Subsequently, a comparison of IOP readings among eyes with low, moderate, and high TMH was also performed.ResultsA total of 120 eyes of 60 patients were enrolled. When comparing the two eyes of a patient, the eye with higher TMH showed higher NCT readings and larger difference in IOP readings between the two tonometries than the eye with lower TMH (P < 0.001 and P < 0.001, respectively). When TMH was classified into grades according to the degree, the high TMH eyes showed higher NCT readings than did the low and moderate TMH eyes (P < 0.001 and P = 0.001, respectively). In addition, the high TMH eyes showed a larger difference in IOP readings between the two tonometries than did the low and moderate TMH eyes (P < 0.001 and P < 0.001, respectively).ConclusionEyes with higher TMH showed higher NCT readings and a larger difference in IOP between the two tonometries (NCT and GAT) than those with lower TMH. In patients with tearing, the NCT value may be inaccurate, so it is necessary to measure the GAT.

Analysis of the changes in the lacrimal system before and after endoscopic dacryocystorhinostomy

“…At present, many studies have con rmed the value of TMH in the diagnosis of dry eyes, and this parameter can re ect the amount of tear secretion to some extent. Although there are some differences in the distribution range of TMH values among different populations, patients can be considered to have dry eyes when the TMH is less than 0.2 mm [21,22,23,24]. In group A, the percentage of eyes with a TMH less than 0.2 mm was 61.76% (21/34) preoperatively, 17.65% (6/34) at 1 month postoperatively, and 0 at 3 months postoperatively (Fig.…”

Future research perspective on the interfacial physics of non-invasive glaucoma testing in pathogen transmission from the eyes

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Goldmann Tonometry and Corneal Biomechanics

“…In addition to the Goldmann applanation tonometer (GAT), which will be further discussed below, several types of tonometers are currently available, each with advantages and disadvantages [23]. The non-contact tonometry (NCT) is influenced by tear meniscus height (TMH), as the measured IOP increases with increasing tear film, and by central corneal thickness (CCT) [24][25][26]. The ocular response analyzer (ORA) uses a jet of air as the applanating force to the apex of the cornea; it can measure corneal hysteresis and the corneal resistance factor and provides higher IOP measurements as compared to GAT [27].…”