Evaluation of Lacrimal Punctal Changes by Anterior Segment Optical Coherence Tomography after Punctal Dilation Versus Punctal Plug Insertion in Cases of Inflammatory Punctual Stenosis

Purpose To compare simple punctal dilation versus punctal dilation augmented by insertion of Punctal Plug Insertion (PPP) with assessing the effect on resolving epiphora and punctum size improvement by an objective method, high-resolution AS-OCT imaging comparing punctal parameters of the patients before and after both techniques. Patients and Methods. It is a prospective, interventional, double-blinded controlled randomized study, which was conducted on two groups of patients, the first epiphora group (EG1 25 eyes), who had acquired punctal stenosis and epiphora and managed by simple punctal dilatation. The second epiphora group (EG2 20 eyes) who managed by punctal dilatation augmented with an application of perforated punctal plugs for two months. Spectral Domain Anterior Segment-OCT Image Acquisition. AS-OCT for lower puncti was performed using RTVue (Optovue Inc., Fermont, CA). OCT images of the width and length of the lower puncti of the participants were captured by the same operator on the same machine. Measuring of punctal size (diameter and length) was performed before treatment, one week, one month, and three months later objectively by using AS-OCT. Results The study included 45 eyes of 50 subjects; the total coverage of epiphora patients fulfilled inclusion criteria and presented to the ophthalmology clinics of Sohag University Hospitals in the period between June 2021 and December 2021. Both groups were comparable regarding mean age (39 ± 11 vs 50 ± 12 years, P value = 0.4) and sex (males were 36% vs 40%, female were 64% vs 60%, P value = 0.5) respectively with no statistically significant difference between both groups. The mean duration of epiphora was measured in both groups before treatment (EG1 = 1.656 ± 0.41 months, EG2 = 1.73 ± 0.32 months) with no statistically significant difference (P value = 0.436). There was marked improvement of the outer punctual diameter and length between outer and inner puncti in EG1 (EG1 391um ± 122 um, EG2 692 ± 226 um (P value < 0.007) and EG1 189 ± 43 um, 380 ± 169 um (P value < 0.0002) during the follow-up period. EG2 showed more improvement than EG1 when compared during the follow-up period in both outer punctual diameter and length between outer and inner puncti with (P value < 0.003 and < 0.0002) in favor of EG2. However; both groups show improvement with the statistically significant difference in both groups by using AS-OCT. Conclusions Punctal dilation augmented by insertion of PPP was an effective method in treating cases of inflammatory punctual stenosis as found by monitoring of punctal parameters changes by AS-OCT. AS-OCT was found a useful method for the evaluation of the lacrimal punctal parameters, especially with different treatment modalities in epiphora cases.


Introduction
Epiphora or tearing is a common complaint in the ophthalmology outpatient clinics with the most commonly accused disease being the acquired punctal stenosis. Reference [1] punctal stenosis can be defined as occlusion or narrowing of the outwards palpebral opening of the lacrimal canaliculi with a patent distal lacrimal drainage system. A more accurate definition is that the punctum size is less than 0.3 mm, or the inability to cannulate the punctum with a 26G cannula without being dilated. [2].
Several methods can be used for the Grading of punctal stenosis. Kashkouli's scoring system is one of the most commonly used methods (grade 0 no punctum (agenesis), grade 1 puncta papilla is covered with a membrane (difficult to recognize), and the grade 2 is less than the normal size but recognizable, grade 3 punctum is normal, grade 4 punctum is small slit (<2 mm), and grade 5 punctum is large slit (≥2 mm)). [3].
ere are various currently used treatment options for the acquired punctal stenosis, including simple repeated combined dilatation of the puncta and canaliculi to overcome any fibrosis or stenosis. Punctal enlargement by dilatation with insertion of adjuvants as (perforated punctal plugs (PPP), mini-monoka canalicular stents (MMC), or self-retaining bicanalicular stents (SRBC)). Punctal dilation and snip incisions, which can also be augmented by insertion of (MMC). [5].
Anterior segment optical coherence tomography (AS-OCT) is a noninvasive, safe, accurate, objective, and crosssectional imaging method used to study the anterior segment of the eye including parameters of lacrimal puncta, cornea, conjunctiva, angle of the anterior chamber, and the lower tear meniscus height. [6,7]. e limited number of studies in the literature that compared the different techniques for the treatment of epiphora resulted in absence of any consensus on which procedure is the best for the treatment of such cases.
is work aimed to compare simple punctal dilation versus punctal dilation augmented by insertion of PPP with assessing the effect on resolving epiphora and punctum size improvement by an objective method, high-resolution AS-OCT imaging comparing punctal parameters of the patients before and after both techniques.

Patients and Methods
e study included 45 eyes of 50 patients of epiphora patients who fulfilled the inclusion criteria and presented to the ophthalmology clinics of Sohag University Hospitals in the period between June 2021 and December 2021.
Patients included in this research were 20 years old or older who had acquired inflammatory punctal edema and were complaining of epiphora and did not respond to medical treatment of epiphora. Punctal stenosis grading of the included groups was graded 1 : 4 according to Kashkouli's classification [3], and epiphora grading was 3 : 5 according to Munk's classification [4].
Patients with a history of previous ocular or lacrimal surgical intervention, trauma, glaucoma disease, corneal abnormalities (abrasions and keratitis), congenital punctal anomalies, and congenital nasolacrimal duct obstruction were excluded. e study design is a prospective, interventional, doubleblinded controlled randomized study, which was conducted on two groups of patients, the first epiphora group (EG1) included 25 eyes, who had acquired punctal stenosis, and epiphora and managed by simple punctal dilatation. e second epiphora group (EG2) included 20 eyes who managed by punctal dilatation augmented with the application of perforated punctal plugs for two months.
In EG1, the procedures were performed under topical anesthesia using proparacaine chloride, the punctum was located using a punctal finder, and punctal dilation and probing, and irrigation were performed using a 26 G lacrimal cannula in the operating room. Patients who were diagnosed as punctal stenosis as a result to canalicular membranous obstruction or a soft stop during probing that could not be overcome were excluded from the study.
In EG2 after completing the procedure done in EG1, silicone plugs (FCI's PVP PRELOADED PERFORATED PLUGS, FCI Ophthalmics, Paris, France) were implanted using their preloaded inserter. ey perform their functions by acting like conformers by maintaining the punctal opening dilated for several weeks allowing tears to be drained. ese plugs are coated with a thin layer of polyvinylpyrrolidone (PVP) to increase the hydrophilic properties of silicone. e final position of the plug was checked to ensure an appropriate fit within the lid margin and explanted after 2 months. Postoperatively in both procedures, topical antibiotics and steroid eye drops were administered for 1 week.
Patients' selection was based on slit-lamp examination of the eyelids, corneal surface, bulbar and palpebral conjunctiva, tear meniscus, intraocular pressure (IOP) measurement, lower punctal examination, and measuring of punctal size (diameter and length) before treatment, one week, one month, and three months later objectively by using AS-OCT.
Spectral Domain Anterior Segment-OCT Image Acquisition. AS-OCT for lower puncti was performed using RTVue (Optovue Inc., Fermont, CA). OCT images of the width and length of the lower puncti of the participants were captured by the same operator on the same machine. e lower eyelid margin was gently everted using a cotton bud that was placed below the punctum. e punctum was everted perpendicular to the light source to allow alignment of the punctum depth concerning the axis of the scanner's infrared beam. e punctum was imaged with the scan line placed horizontally along the mucocutaneous junction. Outer punctal diameter was measured as the distance between the two highest points on the nasal and temporal punctal orifice. Punctal depth is the vertical lumen; it was measured vertically between outer and inner punctal openings which appear closed.
is study was approved by the Ethical Committee of Faculty of Medicine, Sohag University, under IBR registration number S20-160 with clinical trial registration number PACTR202105834743189 and was performed according to the Declaration of Helsinki. e aim of the study and intervention details were discussed with the participants and informed written consent was obtained from them before inclusion. is research received no grant from any funding agency in the public or commercial sectors.

Statistical Analysis.
Statistical analysis was conducted using the SPSS software (version 26.0) (SPSS Inc., Chicago, IL, USA). All participants were chosen by using the systematic random sample technique from the attendees who fulfilled the inclusion criteria. e data were tested for normality using the Kolmogorov-Smirnov test and Shapiro-Wilk test before further statistical analysis; all studied variables were not normally distributed. Differences between groups for continuous measures were analyzed by a Mann-Whitney U test and Wilcoxon Signed Ranks Test for categorical measures.

Results
e study included 45 eyes of 50 subjects who were divided into two groups of patients, the first epiphora group (EG1:25 eyes), who had acquired punctal stenosis and epiphora and managed by simple punctal dilatation. e second epiphora group (EG2:20 eyes) who managed by punctal dilatation augmented with the application of perforated punctal plugs for two months.
Both groups were comparable regarding mean age (39 ± 11 vs 50 ± 12 years, P value � 0.4) and sex (males were 36% vs 40%, female were 64% vs 60%, P value � 0.5) respectively with no statistically significant difference between both groups (Table 1). Mean duration of epiphora was measured in both groups before treatment (EG1 � 1.656 ± 0.41 months, EG2 � 1.73 ± 0.32 months) with no statistically significant difference (P value � 0.436). Various etiologies of acquired Punctal stenosis were summarized in Table 2. e outer diameter and the length of the lower punctum of both groups before treatment and during the followup period comparing both groups were assessed objectively by AS-OCT and summarized in (Tables 3 and 4).
ere was marked improvement of the outer punctual diameter and length between outer and inner puncti in EG1 (EG1 391 um ± 122 um, EG2 692 ± 226 um (P value < 0.007) and EG1 189 ± 43 um, 380 ± 169 um (P value < 0.0002) during the followup period. EG2 showed more improvement than EG1 when compared during the followup period in both outer punctual diameter and length between outer and inner puncti with (P value < 0.003 and < 0.0002) in favor of EG2. However; both groups show improvement with a statistically significant difference in both groups by using AS-OCT (Figures 1 and 2). Figures 3 and 4 show AS-OCT of the outer punctual diameter and length between outer and inner puncti in EG1 and EG2.
Subjective assessment of the improvement in both groups using Munk's test was summarized in (Table 5). Both groups showed significant objective improvement using Munk's test, which was more in EG2 when compared to EG1.

Discussion
In 1989, Bernard et al. [8] described the temporary use of punctal stenting with perforated punctal plugs in cases of acquired punctal stenosis, and several studies after that tried to evaluate the success rates of punctal plug used with promising results. [9,10] is study is a prospective, interventional, double-blinded controlled randomized study, which was performed on two groups of patients, the first epiphora group (EG1 25 eyes), who had acquired    punctal stenosis and epiphora and managed by simple punctal dilatation. e second epiphora group (EG2) who managed by punctal dilatation augmented with the application of perforated punctal plugs for two months. Both groups were evaluated and followed up by using AS-OCT which is a non-invasive imaging method used in previous studies for the evaluation of normal and stenosed punctal [4,11], and tear meniscus in normal persons. [12] It has been used to examine the proximal lacrimal system, and many studies have investigated the measurement of the anatomical parameters, evaluating the results of punctoplasty, and detecting lacrimal lesions. [13,14].
Our study aimed to compare simple punctal dilation versus punctal dilation augmented by insertion of PPP with assessing the effect on resolving epiphora and punctum size improvement by an objective and quantitative method, high-resolution AS-OCT imaging to compare punctal parameters of the patients before and after both techniques. e follow-up period was 3 months in both groups of the study with clinical and OCT followup, EG2 showed more improvement than EG1 when compared during the followup period in both outer punctual diameter and length between outer and inner puncti with (P value < 0.003 and < 0.0002) in favor of EG2. However; both of the study groups show marked improvement with the statistically significant difference in both groups by using imaging of AS-OCT.
In a study of Abdallah RMA et al, [15] they evaluated the patency and position of perforated lacrimal punctal plugs implanted for treating punctal stenosis together with quantitative assessment of the tear film using AS-OCT, they found that ere was a statistically significant postoperative decrease of tear meniscus area and tear meniscus area (P < 0.001) and postoperative epiphora Munk score (P < 0.001).
Different studies evaluated the efficacy of perforated lacrimal punctal plugs implanted for treating punctal stenosis, in a study of Ozgur et al, [16] they evaluated the efficiency of perforated punctal plugin acquired punctal Pre Post Figure 3: A case of EG1 of simple punctal dilatation before and after treatment.
Pre plug During plug Post plug Figure 4: A case of EG2 of punctal dilatation augmented with the application of perforated punctal plugs before, during, and after treatment. stenosis, they found epiphora decreased remarkably in 88.9% of the patients 1 month after plug implantation, except one whose plug dropped off spontaneously in 2 weeks. In a study of Chang et al, [17] they reported the success rates for perforated punctual plug (PPP) in the management of acquired punctual stenosis, in a retrospective, cross-sectional, comparative study. ey concluded that perforated punctual plug implantation for the treatment of acquired punctual stenosis and obstruction is very effective.
In our study, e plugs were explanted after 2 months with no reported cases of spontaneous extrusion or migration.
Limitations of this study included the small sample size of cases involved in the research (45 eyes), and also, the short period of followup was another limitation (three months), further studies are needed in the future with a larger sample size, and longer followup period to document the efficacy of these plugs in longterm results.
In conclusion; punctal dilation augmented by the insertion of PPP was an effective method in treating cases of inflammatory punctual stenosis as found by monitoring of punctal parameters changes by AS-OCT. AS-OCT was found a useful method for the evaluation of the lacrimal punctal parameters, especially with different treatment modalities in epiphora cases.

Data Availability
e data used to support the results of this study are available from the corresponding author upon request. Disclosure e article has not been presented in a meeting. We clarified that there is a novel scientific content presented in this manuscript, which is completely different from our previous publication in the journal about the same topic.

Conflicts of Interest
e authors declare that they have no conflicts of interest.