Changes in cytokines in tears after endoscopic endonasal dacryocystorhinostomy for primary acquired nasolacrimal duct obstruction

[Pharmacological prevention of fibrosis in dacryosurgery]

Chronic inflammatory process in the lacrimal drainage system is the main etiological factor leading to dacryostenosis and consequent obliteration - partial and total nasolacrimal duct obstruction. Prevention of this process is an urgent problem in dacryology. Currently, there is very little research on the development and use of conservative methods for treating dacryostenosis using anti-inflammatory, as well as anti-fibrotic drugs. In this regard, the main method of treating lacrimal drainage obstruction is dacryocystorhinostomy. However, the problem of recurrence after this operation has not been resolved. The causes of recurrence can be cicatricial healing of dacryocystorhinostomy ostium, canalicular obstruction, formation of granulations and synechiae in its area. Surgical methods of recurrence prevention are associated with possible complications, and there is conflicting data on the feasibility of their use. Based on this, the development of pharmacological methods for the prevention of fibrosis in dacryology is promising, among which the antitumor antibiotic Mitomycin C is the most studied. However, there are no specific scientifically substantiated recommendations for the use of this drug, and the data on its effectiveness vary. This has prompted researchers to look for and study alternative anti-fibrotic agents, such as antitumor drugs, glucocorticoids, hyaluronic acid, small molecule, biological, immunological and genetically engineered drugs, as well as nanoparticles. This review presents the current data on the efficacy and prospects of the use of these drugs in dacryology.

Proportion and characteristics of lacrimal drainage pathway disease and keratopathy in non-infectious corneal perforation using lacrimal syringing test

Lacrimal drainage pathway disease-associated keratopathy (LDAK) has been associated with corneal perforation, which arises from both infectious and non-infectious corneal disorders. However, patients with corneal perforation are often not routinely tested for LDAK, and the potential risk posed by LDAK in the development of corneal ulcers has not been investigated in detail. This study aimed to assess the proportion and characteristics of LDAK in patients with non-infectious corneal perforation using lacrimal syringing test. This study enrolled 56 patients with corneal perforation treated at Saitama Medical University Hospital between January 2016 and September 2022. The causes of corneal perforation were trauma (n = 17, 30%), infection (n = 19, 34%), non-infection (n = 16, 29%), and unknown (n = 4, 7%). A lacrimal syringing test was performed on 12 patients with non-infectious corneal perforation and 4 with an unknown diagnosis. Among the 16 patients with non-infectious corneal perforation, 13 (81%) had lacrimal drainage disease, but only 3 (19%) patients had lacrimal puncta, as revealed by slit-lamp examinations. The primary bacterial species identified in lacrimal obstructive disease and lacrimal canaliculitis were Staphylococcus spp. and Actinomycetes spp. respectively. Lower temporal and peripheral corneal perforations were common. All patients underwent lacrimal surgery, and 6 (38%) were treated for corneal perforation without corneal surgery. Interestingly, several patients with LDAK who did not exhibit any lacrimal duct obstruction on slit-lamp examination. The study findings demonstrate the significance of the lacrimal syringing test for assessing LDAK in patients with corneal perforation, indicating LDAK as a potential cause of corneal perforation.

Etiopathogenesis of primary acquired nasolacrimal duct obstruction (PANDO)

Primary acquired nasolacrimal duct obstruction, or PANDO, is a common adult lacrimal drainage disorder. The current treatment modality of dacryocystorhinostomy to bypass the obstructed nasolacrimal duct has excellent outcomes. However, the understanding of the disease etiopathogenesis needs to be revisited. There are not many studies that specifically assessed any hypothesis or ones that convincingly put forth the presumed or confirmed interpretations regarding the PANDO pathogenesis or the mechanisms or pathways involved therein. Histopathological evidence points to recurrent inflammation of the nasolacrimal duct, subsequent fibrosis, and the resultant obstruction. The disease etiopathogenesis is considered multifactorial. Several implicated suspects include anatomical narrowing of the bony nasolacrimal duct, vascular factors, local hormonal imbalance, microbial influence, nasal abnormalities, autonomic dysregulation, surfactants, lysosomal dysfunction, gastroesophageal reflux, tear proteins, and deranged local host defenses. The present work reviewed the literature on the etiopathogenesis of primary acquired nasolacrimal duct obstruction (PANDO) to gain insights into the present state of the understanding and the high-value translational implications of precisely decoding the disease etiology.

Meibomian Gland Dysfunction in Primary Acquired Nasolacrimal Duct Obstruction

This study was designed to investigate the influence of primary nasolacrimal duct obstruction (PANDO) on the structure and function of the Meibomian gland and to examine whether it is related to functional failure after dacryocystorhinostomy surgery. Medical records of patients diagnosed as PANDO from August 2021 to February 2022 were retrospectively studied. Results of slit lamp examination, lacrimal drainage test, tear break-up time, anterior segment optical coherence tomography, and meibography were collected. Tear meniscus height, tear break-up time, meiboscore, and lipid layer thickness of tear membrane were parameters compared between the eyes with complete PANDO and the control group. Medical records of 44 patients, therefore 88 eyes were collected, and there were 28 eyes with complete PANDO (total obstruction group), while normal eyes (control group) were 30. Mean tear meniscus height was significantly higher than that of the control group ( P value<0.001), but tear break-up time ( P value=0.322), lipid layer thickness ( P value=0.755), and meiboscore ( P value=0.268) were not significantly different. However, in the cases with moderate and severe meibomian gland destruction, the lipid layer thickness of the total obstruction group was significantly thinner than the control group. Lipid secretion of meibomian glands was less in eyes with PANDO than in eyes without PANDO, under moderate to severe meibomian gland destruction. It can lead to persistent epiphora after dacryocystorhinostomy due to a compensatory response against evaporative dry eye disease. Patients should be educated before the decision to undergo surgeries about the possibilities of persistent epiphora. Further studies are needed to prove the mechanism of meibomian gland function disturbance in PANDO.

Ocular injury progression and cornea histopathology from chloropicrin vapor exposure: Relevant clinical biomarkers in mice

Ocular tissue is highly sensitive to chemical exposures. Chloropicrin (CP), a choking agent employed during World War I and currently a popular pesticide and fumigating agent, is a potential chemical threat agent. Accidental, occupational, or intentional exposure to CP results in severe ocular injury, especially to the cornea; however, studies on ocular injury progression and underlying mechanisms in a relevant in vivo animal model are lacking. This has impaired the development of effective therapies to treat the acute and long-term ocular toxicity of CP. To study the in vivo clinical and biological effects of CP ocular exposure, we tested different CP exposure doses and durations in mice. These exposures will aid in the study of acute ocular injury and its progression as well as identify a moderate dose to develop a relevant rodent ocular injury model with CP. The left eyes of male BALB/c mice were exposed to CP (20% CP for 0.5 or 1 min or 10% CP for 1 min) using a vapor cap, with the right eyes serving as controls. Injury progression was evaluated for 25 days post-exposure. CP-exposure caused a significant corneal ulceration and eyelid swelling which resolved by day 14 post exposure. In addition, CP-exposure caused significant corneal opacity and neovascularization. Development of hydrops (severe corneal edema with corneal bullae) and hyphema (blood accumulation in the anterior chamber) was observed as advanced CP effects. Mice were euthanized at day 25 post-CP-exposure, and the eyes were harvested to further study the corneal injury. Histopathological analyses showed a significant CP-induced decrease in corneal epithelial thickness and increased stromal thickness with more pronounced damage, including stromal fibrosis, edema, neovascularization, trapped epithelial cells, anterior and posterior synechiae, and infiltration of inflammatory cells. Loss of the corneal endothelial cells and Descemet's membrane could be associated with the CP-induced corneal edema and hydrops which could lead to long term term pathological conditions. Although exposure to 20% CP for 1 min caused more eyelid swelling, ulceration, and hyphema, similar effects were observed with all CP exposures. These novel findings following CP ocular exposure in a mouse model outline the corneal histopathologic changes that associate with the continuing ocular clinical effects. The data are useful in designing further studies to identify and correlate the clinical and biological markers of CP ocular injury progression with acute and long-term toxic effects on cornea and other ocular tissues. We take a crucial step towards CP ocular injury model development and in pathophysiological studies to identify molecular targets for therapeutic interventions.

Tear instability in the fellow eye of unilateral nasolacrimal obstruction and resolution with dacryocystorhinostomy

PURPOSE

To determine the effect of unilateral primary acquired nasolacrimal obstruction (PANDO) on ocular surface parameters in PANDOeyes and fellow eyes and changes in these parameters after dacryocystorhinostomy.

METHODS

Tear osmolarity, tear break-up time (TBUT), Schirmer's test, Meibomian gland score, and Lissamine Green staining of PANDO eyes and fellow eyes were measured preoperatively and postoperatively at Day 15, 1 month, and 3 months. Lacrimal irrigation and epiphora symptomatology were evaluated at all follow-up visits, and patients who did not meet surgical success criteria were excluded from the study.

RESULTS

Twenty-nine patients who underwent successful dacryocystorhinostomy surgery were included in the study. Preoperative and postoperative Day 15 Schirmer (p = .019, p = .001) and TBUT (p = .039, p = .043) were significantly lower in the fellow eye compared to PANDO eyes. The differences observed between PANDO eyes and fellow eyes in all other parameters were not significant (p > .05). Preoperatively PANDO eye parameters were normal, whereas TBUT (7.59 ± 5.39 s) and tear osmolarity (308.59 ± 17.32 mOsm/L) values of the fellow eye may be indicative of tear film instability. TBUT and tear osmolarity of the fellow eye showed significant improvement 3 months postoperatively compared to preoperative values (p = .010; p = .027 respectively).

CONCLUSION

Schirmer and TBUT values of the fellow eye were significantly lower than PANDO eyes preoperatively, one month after surgery there was no significant difference. TBUT and tear osmolarity of the fellow eyes may be indicative of tear instability preoperatively with improvement 3 months after dacryocystorhinostomy.

Clinical characteristics of lacrimal drainage pathway disease-associated keratopathy

Purpose

To report the clinical characteristics of 13 cases of noninfectious corneal ulceration related to lacrimal drainage pathway disease.

Methods

Medical records of 13 patients with lacrimal drainage pathway disease-associated keratopathy who were examined at Ehime University Hospital between April 2007 and December 2021 were analyzed.

Results

The predisposing lacrimal drainage pathway diseases for corneal ulceration were chronic dacryocystitis in seven patients and lacrimal canaliculitis in six patients. The corneal ulcers were located at the peripheral cornea in 10 patients and the paracentral cornea in three patients. All patients indicated few cellular infiltrations of the ulcerated area at the slit-lamp examination. Corneal perforation was found in seven patients. The primary identified organisms were Streptococcus spp. in chronic dacryocystitis and Actinomycetes spp. in lacrimal canaliculitis. All patients showed rapid healing of the epithelial defects after treatment of the lacrimal drainage pathway disease. The mean time elapsed between treatment of the lacrimal drainage pathway disease and re-epithelialization of corneal ulcer was 14.5 ± 4.8 days.

Conclusion

Lacrimal drainage pathway disease-associated keratopathy may be characterized by peripheral corneal ulcer with few cellular infiltrations, occasionally leading to corneal perforation. Treatment of the lacrimal drainage pathway disease could be the most effective treatment for lacrimal drainage pathway disease-associated keratopathy.

Changes in Tears Monocyte Chemoattractant Protein-1 Level After External Dacryocystorhinostomy in Primary Acquired Nasolacrimal Duct Obstruction

BACKGROUND

The authors aimed to define tears monocyte chemoattractant protein-1 (MCP-1) changes after external dacryocystorhinostomy surgery.

MATERIALS AND METHODS

Tears samples were collected with a Schirmer strip and stored in Eppendorf tubes at -80°C. At the end of the study, the papers were cut into small pieces and incubated with phosphate-buffered saline solution. Monocyte chemoattractant protein-1 levels were determined by using an enzyme-linked immunosorbent assays kit.

RESULTS

The MCP-1 levels were 498.66±101.35, 576.40±149.78, 422.53±85.94, and 436.96±81.38 ng/L before surgery, in the first week, the first, and third months after surgery, respectively. Its level significantly increased in the first week compared with the preoperative level ( P <0.001). There was a prominent decrease in the postoperative first month ( P <0.001). In the third postoperative month, the mean MCP-1 level was not significantly increased compared with the postoperative first month ( P =0.196).

CONCLUSION

The tears MCP-1 level was significantly decreased after external dacryocystorhinostomy surgery.

Detection & analysis of inflammatory cytokines in tears of patients with lacrimal duct obstruction

Background & objectives

Tear proteomic changes can be a candidate etiopathogenesis of lacrimal duct obstruction diseases (LDODs). Studies on proteomics have focused primarily on nasolacrimal duct obstruction, and some specific inflammatory cytokines such as interferon (IFN)-α2a, interleukin (IL)-8 and IL-10, have not been investigated. In addition, differences in inflammatory cytokines in tears according to the LDOD subtype have not been reported. This study aimed to quantitatively compare inflammatory cytokines in tears from patients with LDOD and investigate tear-cytokine differences among different LDOD subtypes.

Methods

Tear samples were collected from both eyes of 30 patients with unilateral LDOD: five patients with prelacrimal obstruction, five with acute dacryocystitis and 20 with chronic dacryocystitis. The contralateral eyes were used as controls. IFN-α2a, IFN-β, IFN-γ, IL-17A, IL-6, IL-8, tumour necrosis factor-alpha (TNF-α), vascular endothelial growth factor (VEGF)-A, induced protein-10 (IP-10) and monocyte chemotactic protein-1 (MCP-1) were quantified in all samples.

Results

The expression of eight cytokines (except for IP-10 and MCP-1) were significantly increased in the affected eyes compared with those in the control eyes. The levels of nine inflammatory cytokines (except for IP-10) in the affected eyes of patients with chronic dacryocystitis were higher than those in the affected eyes of patients with prelacrimal obstruction. In addition, patients with chronic dacryocystitis presented significantly higher IFN-γ level than those with prelacrimal obstruction or acute dacryocystitis.

Interpretation & conclusions

Specific pro-inflammatory cytokines were increased in tears of patients with LDOD compared with those in the controls. The specific cytokine profiles observed in the tears of individuals with different LDOD subtypes may be associated with the unique aetiopathogenesis of these conditions.

Matrix Metalloproteinase-9 Point-of-Care Immunoassay after Dacryocystorhinostomy in Patients with Nasolacrimal Duct Obstruction

PURPOSE

To compare matrix metalloproteinase-9 (MMP-9) point-of-care immunoassay (InflammaDry) results before and after dacryocystorhinostomy (DCR) in patients with nasolacrimal duct (NLD) obstruction.

METHODS

Thirty-eight eyes of 38 patients who were diagnosed with unilateral NLD obstruction were treated with endoscopic DCR. Treatment response was monitored using InflammaDry test, tear meniscus height was measured by slit-lamp microscopy, and tear meniscus parameters (tear meniscus height, depth, and area) were measured by anterior segment optical coherence tomography at baseline and at 1 month after surgery.

RESULTS

In 38 patients, the positive percentage of MMP-9 in diseased eyes was 100% (38 eyes), much higher than that in healthy fellow eyes (13.2%, 5 of 38 eyes) at baseline (p<0.001, χ² test test). MMP-9 levels before and after surgery were significantly different (p<0.001), and MMP-9-positive eyes showed a significant improvement in MMP-9 grade after surgery (p< 0.0001; generalized McNemar test). Furthermore, other clinical parameters (tear meniscus area, tear meniscus height, and tear meniscus depth) showed a general improvement.

CONCLUSION

The concentration of MMP-9 increased in the tears of patients' eyes with NLD obstruction compared to the contralateral healthy eyes. These abnormal findings showed a significant improvement after DCR. The improvement of postoperative MMP-9 expression might be because of the improvement of tear retention.

Modified ocular surface disease index as a screening criteria for dry eye syndrome presenting after successful dacryocystorhinostomy

Objective

To find preoperative screening criteria for dry eye syndrome (DES) that present after successful endoscopic dacryocystorhinostomy (EDCR).

Methods

We retrospectively analyzed medical records of 110 patients who underwent EDCR for nasolacrimal duct obstruction. DES diagnostic criteria were defined as tear break-up time (TBUT) less than 10 seconds, and ocular surface disease index (OSDI) score greater than 13 points. After EDCR, patients were divided into DES group and control group according to the DES diagnostic criteria. Preoperative OSDI score alone or in combination of preoperative TBUT and OSDI score were used to find screening criteria, which could discriminate the two groups preoperatively with a high positive predictive value (PPV). Criteria A was set same as the diagnostic criteria of DES, and Criteria B and C were set to improve PPV by increasing specificity while maintaining similar sensitivity to Criteria A.

Results

Thirty patients (27.3%) were diagnosed with DES after EDCR, while 80 patients (72.7%) were normal. In patients with DES, preoperative TBUT was not different (p = 0.851), but OSDI score was significantly higher (p<0.001). Criteria A showed a sensitivity of 73.3%, specificity of 55.0%, and PPV of 38.0%. Criteria B and C excluded preoperative TBUT, which had no difference between the two groups, and set screening criteria with preoperative OSDI score alone. Criteria B (preoperative OSDI score of 19.6 points or more) showed a sensitivity of 75.0%, specificity of 60.6%, PPV of 41.7% and AUC of 0.739 (p < 0.001). Criteria C was consisted of 5 out of 12 OSDI items that showed significant differences between the two groups; blurred vision, reading, working with a computer, low humidity, and air conditioning. Criteria C (preoperative 5-item OSDI score of 24.4 points or more) was a better predictability, with a sensitivity of 75.0%, specificity of 71.3%, PPV of 49.5%, and AUC of 0.804 (p < 0.001). The AUC of Criteria C was significantly higher than that of Criteria B (p = 0.0037).

Conclusion

DES occurred after successful EDCR in 27.3% of patients, and an OSDI questionnaire helped to screen DES. The predictability could improve using the modified OSDI score which showed noticeable difference in five OSDI items before and after EDCR.

Tear protein analysis in patients with primary acquired nasolacrimal duct obstruction treated with lacrimal passage intubation

PURPOSE

The pathophysiology of nasolacrimal duct obstruction (NLDO) may involve quantitative as well as qualitative changes in tears. We measured tear protein concentrations in patients with primary acquired NLDO and compared them with the tear proteins in healthy individuals and patients with dry eye disease.

STUDY DESIGN

Case-control study.

METHODS

Twenty-four patients diagnosed with primary acquired NLDO who underwent endoscopic lacrimal passage intubation were included in the study. Tear fluid was collected with Schirmer's test strips three times: before intubation, after intubation while the nasolacrimal tube was in place, and after extubation. At the same time, 24 age-matched normal controls and 24 patients with dry eye were selected from subjects whose tears were collected during the same study period. We measured the following components of tear fluid: total protein, lactoferrin, albumin, and interleukin 6 (IL-6) levels.

RESULTS

Total proteins and albumin levels in tears of the NLDO group were significantly lower than those of the control group (P < 0.001 and P = 0.014, respectively, Mann-Whitney U test). Total proteins, albumin, and lactoferrin levels were significantly increased after extubation of nasolacrimal tube (P < 0.001, P = 0.004, and P = 0.029, respectively, Wilcoxon matched-pairs signed-rank test). There were no statistically significant differences in total protein, albumin, lactoferrin and IL-6 levels between patients with NLDO after lacrimal passage extubation and controls.

CONCLUSIONS

Our study shows distinct differences in protein composition of tear fluid in NLDO eyes and demonstrates that these can be normalized by nasolacrimal tube placement.

Berberine hydrochloride inhibits inflammation and fibrosis after canalicular laceration repair in rabbits

AIMS

This study was designed to investigate the molecular mechanisms underlying the anti-inflammatory and anti-fibrosis effects of Berberine hydrochloride (BBR) following canalicular laceration (CL) surgical repair.

MAIN METHODS

We used a rabbit CL model in this study. BBR and the control medicine were administered during and after the surgical operation. The degree of fibrosis in the canaliculi was evaluated using hematoxylin and eosin and Masson's trichrome staining 7 days after the operation. Inflammation inside the canaliculi was observed using a transcanalicular endoscope. Expression levels of inflammatory cell cytokines [tumor growth factor-β1 (TGF-β1), connective tissue growth factor (CTGF), intracellular adhesion molecule-I (ICAM-1), and interleukin-β1 (IL-1β)] were detected using immunohistochemistry. P38 and ERK1 phosphorylation and activation were determined using western blot analysis.

KEY FINDINGS

The degree of inflammation and fibrosis were less in the BBR groups compared to Surgery group. The anti-inflammatory and anti-fibrosis effects of BBR were concentration-dependent. The levels of TGF-β1, CTGF, ICAM-1, and IL-1β were significantly lower in the BBR groups compared to Surgery group. BBR reduced the phosphorylation of P38 compared to Surgery group.

SIGNIFICANCE

In conclusion, this study shows that BBR can reduce local fibrosis after CL surgical repair via its anti-inflammatory and anti-fibrosis effects.

The Use of Stents in Children with Nasolacrimal Duct Obstruction Requiring Surgical Intervention: A Systematic Review

Nasolacrimal duct obstruction (NLDO) is the most common cause of childhood epiphora. It is managed conservatively in the first year of life, after which surgical treatment is classically based on a stepwise paradigm of probing, intubation, and dacryocystorhinostomy. This systematic review aims to present the current role of intubation in the management of children with NLDO requiring surgical intervention. A search for English-language articles from the electronic databases PubMed, SCOPUS, and the COCHRANE library was conducted over a period of five months in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and the Cochrane Handbook. The following keywords were used to aid retrieval: stents, children, lacrimal intubation, endoscopic dacryocystorhinostomy, external dacryocystorhinostomy, NLDO, dacryocystitis, congenital, acquired. The primary outcome was defined as the success of the intervention, determined by resolution of symptoms and patency of the lacrimal anatomy confirmed by the fluorescein dye disappearance test or syringing. Secondary outcomes included the presence of complications. A total of 144 articles were identified; of these, 35 fulfilled the study criteria. The majority of the included studies involved lacrimal intubation alone, followed by intubation as an adjunctive procedure to balloon dacryoplasty and dacryocystorhinostomy. The overall success rate of these procedures ranged from 41.1% to 100%. Post-operative complications were reported in 65.7% of the included studies. Lacrimal intubation was most commonly performed as a primary procedure in children with NLDO, with high success rates. The main complication was stent dislodgement. There is lack of evidence regarding the benefit of intubation over probing as primary treatment of congenital NLDO. In the absence of high-quality evidence, the decision of whether to perform lacrimal intubation in children with NLDO requiring surgical intervention depends on clinical judgement and other&nbsp;low-level evidence, such as observational non-randomised trials.

Rebamipide promotes lacrimal duct epithelial cell survival via protecting barrier function

Nasolacrimal duct obstruction (NLDO) is thought to be due to inflammation and fibrosis of lacrimal duct epithelial cells (LDECs). Here we investigated the effect of rebamipide, a drug that is used for the protection of the mucosa and the treatment of gastritis and gastroduodenal ulcers, on LDECs, both in vitro and in vivo. In this study, LDECs were cultured from rabbit lacrimal duct tissues, and the barrier function of LEDCs was examined in vitro via transepithelial electrical resistance (TER) measurement, with or without interleukin (IL)-6 and/or rebamipide. For the in vivo examination, benzalkonium chloride (BAC) was injected into the rabbit lacrimal ducts, followed by the application of rebamipide or a placebo vehicle alone. The results of the in vitro examination revealed a significant decrease in TER in the group treated with IL-6 alone compared with the placebo-vehicle group (p < 0.05) and the group treated with IL-6 and rebamipide (p < 0.01). The results of the in vivo examination revealed that the infiltration of neutrophils under the basement membrane and the disruption of tight junction proteins with BAC injection and rebamipide attenuates the disturbance of tissue construction. These results suggest that rebamipide protects LDECs via an anti-inflammatory effect and preserves the barrier function of those cells.

Etiopathogenesis of Primary Acquired Nasolacrimal Duct Obstruction: What We Know and What We Need to Know

PURPOSE

To provide a systematic review of the literature on the etiopathogenesis of primary acquired nasolacrimal duct obstruction (PANDO).

METHODS

The authors performed a PubMed search of all articles published in English with specific reference to etiopathogenesis of PANDO or associations of PANDO. Data captured include demographics, study techniques, hypothesis, presumed or confirmed interpretations with regards to pathogenesis, mechanisms, or pathways. Specific emphasis was laid on addressing the lacunae and potential directions for future research.

RESULTS

Numerous factors are believed to contribute to the etiopathogenesis of PANDO. The basic pathogenesis involves inflammation, vascular congestion, mucosal edema, fibrosis, obstruction, and stasis. Bony nasolacrimal duct diameter does not appear to play a significant role. There is no convincing data to substantiate nose as the site of disease origin and nasal factors appear to be comorbidities. Hormonal mechanisms are more evidence-based but can only partly explain the pathogenesis. Vascular theories are based on the behavior of perilacrimal cavernous bodies, their autonomic control, and additional structural changes in the helical patterns of connective tissue fiber arrangements. Repeated vascular malfunction leading to structural epithelial and subepithelial changes currently appears to be the most evidence-based and accepted theory. Tear proteomics holds a promise in decoding the etiopathogenesis of PANDO, at least in part.

CONCLUSIONS

The etiopathogenesis of PANDO appears to be multifactorial. Hormonal microenvironments, vascular factors, and tear proteomics are promising candidates for further work. There is a need for focused work by Clinician-Scientists and the answers can have far reaching clinical implications.

Evaluation of Tear Film Lipid Layer Thickness Measurements Obtained Using an Ocular Surface Interferometer in Nasolacrimal Duct Obstruction Patients

Purpose

To compare the tear film lipid layer thickness (LLT) between patients with incomplete nasolacrimal duct obstruction (NLDO) and normal controls and to analyze the changes in tear film LLT and blinking pattern after silicone tube intubation in NLDO patients.

Methods

We reviewed the medical records of 68 eyes in 52 incomplete NLDO patients who underwent silicone tube intubation from January 2017 to July 2017. The LLT, blinking pattern, and Meibomian gland image were measured with the LipiView II ocular surface interferometer. The Meibomian gland drop-out ratio was measured using the polygon selection tool in the Image J program. Tear meniscus height, which is the other lacrimal indicator, was assessed with spectral-domain optical coherence tomography.

Results

Tear meniscus height was significantly decreased after silicone tube intubation (p < 0.01). Preoperative minimum, maximum, and average LLT values were 62.4 ± 24.0, 86.7 ± 17.9, and 71.7 ± 23.3 nm, respectively. Significant changes in the minimum, maximum, and average LLT (74.8 ± 23.6, 98.8 ± 11.0, and 91.6 ± 16.1 nm, respectively) were observed after silicone tube intubation (p < 0.001, p = 0.001, and p < 0.001). The partial blinking/total blinking ratio in 20 seconds and the Meibomian gland drop-out ratio showed no significant change after silicone tube intubation.

Conclusions

Overall, the LLT was increased after silicone tube intubation. Silicone tube intubation may be helpful in maintaining LLT with a normalized of amount of tears.

[Influence of TGF-β cytokine and a number of other biochemical factors on regenerative process]

Scarring is one of the main causes of surgical failure in a number of eye diseases, dacryologic conditions in particular. The process of wound healing, including postoperative wound healing, goes through several stages mediated by various biochemical factors, such as growth factors and pro- and anti-inflammatory cytokines. The balance between the latter directly influences the wound healing. However, current data on the effect of these factors on postoperative outcomes are few and contradictory. Thus, in dacryology as well as in other areas of ophthalmology, the role of cytokines and growth factors in healing of surgical wounds is being intensively researched.

Conjunctival cytologic features in patients with unilateral primary acquired nasolacrimal duct obstruction

PURPOSE

To evaluate the cytologic features of conjunctival epithelium in patients with unilateral primary acquired nasolacrimal duct obstruction (PANDO) using impression cytology.

METHODS

Twenty-four patients with unilateral PANDO for at least 1 year were enrolled in this study. The healthy eyes of the patients are assessed as control group. All patients were subjected to ophthalmic surface examination with conjunctival impression cytology analysis. Squamous metaplasia and goblet cell density were graded according to Nelson grading system.

RESULTS

The mean age was 52.7 ± 16.3 (range 21-70) years. The mean period for complaints of epiphora was 3.2 ± 2.4 (range 1-8) years. The eye with PANDO had a mean squamous metaplasia grade of 2.38 ± 0.59 versus 1.91 ± 0.82 for control eyes (p = 0.011). The mean grade of goblet cell density was 2.0 ± 0.51 for eyes with PANDO and 2.38 ± 0.65 for control eyes (p = 0.013). There was no statistically significant correlation between conjunctival cytological features in terms of squamous metaplasia and goblet cell density grades and duration of epiphora complaint (r = -0.04, p = 0.82; r = 0.09, p = 0.66, respectively).

CONCLUSIONS

PANDO may cause alterations in conjunctival impression cytology. Successful dacryocystorhinostomy surgeries will help to protect ocular surface health.

Meibomian gland dysfunction and tear cytokines after cataract surgery according to preoperative meibomian gland status

BACKGROUND

To investigate the possible mechanisms by which cataract surgery aggravates meibomian gland dysfunction (MGD), we evaluated the changes in tear cytokines and ocular surface parameters after cataract surgery according to the preoperative MGD grade.

DESIGN

Prospective, observational case series.

PARTICIPANTS

A total of 50 eyes from 50 patients who underwent cataract surgery were included.

METHODS

Patients were classified into two groups: Group I had no or minimal MGD, and group II had grades 2-4 MGD. Ocular surface parameters were measured, including tear film break-up time, Schirmer I test, ocular surface staining and Ocular Surface Disease Index, and tear cytokine levels were measured.

MAIN OUTCOME MEASURES

The main outcomes were changes in ocular surface parameters and inflammatory tear cytokine concentrations.

RESULTS

In group II, preoperative MGD grade, ocular surface staining, tear film break-up time and Ocular Surface Disease Index were worse, and mean interleukin (IL)-2, IL-6 and TNF-α levels were higher than those of group I. MGD and ocular surface parameters were worsened to a greater degree after surgery in group II than in group I (P < 0.050). In group II, IL-6 and TNF-α levels significantly increased at postoperative 1 month, and there were significant correlations between changes in ocular surface parameters and tear cytokines (IL-2, IL-6 and TNF-α; P < 0.050).

CONCLUSIONS

The extent to which the MGD grade was aggravated following cataract surgery differed based on preoperative MGD grade. Preoperative MGD and ocular surface status should be carefully evaluated.

[Therapeutic methods of scar prevention at the site of endonasal dacryocystorhinostomy]

Success rate of endonasal dacryocystorhinostomy (DCR) varies from 82% to 91%. The bulk of unsatisfactory results is due to excessive scarring at the site of the created opening (dacryostoma, DS). Mitomycin C is the most extensively studied drug of those affecting regeneration processes, however, the data on its efficacy at DS site is contradictory. Despite ongoing search for new agents able to interfere in the physiological process of scarring, the number of relevant studies is yet insufficient. Thus, development of methods of scarring prevention after endonasal DCR takes the highest priority in dacryology.

Kinetic Profiles of Inflammatory Mediators in the Conjunctival Sac Fluid of Patients upon Photorefractive Keratectomy

Photorefractive keratectomy (PRK) represents a therapeutic option to remodel corneal stroma and to compensate refractive errors, which involves inflammatory and/or regenerative processes. In this context, the modulation of cytokines/chemokines in the conjunctival sac fluid and their role in the maintenance of the corneal microenvironment during the healing process upon refractive procedures has not been deeply investigated. In this study, serial samples of conjunctival sac fluid of patients (n = 25) undergoing PRK were harvested before and at different time points after surgery. The levels of 29 cytokines/chemokines/growth factors involved in inflammatory/immune processes were measured with a multiplex array system. The results have firstly highlighted the different pattern of cytokine expression between the microenvironment at the anterior surface of the eye and the systemic circulation. More importantly, the kinetic of modulation of cytokines/chemokines at the conjunctival level following PRK revealed that while the majority of cytokines/chemokines showed a significant decrease, MCP-1 emerged in light of its pronounced and significant increase soon after PRK and during the follow-up. This methodological approach has highlighted the role of MCP-1 in the healing process following PRK and has shown a potential for the identification of expression/modulation of soluble factors for biomarker profiling in ocular surface diseases.

Human Serum Eye Drops in Eye Alterations: An Insight and a Critical Analysis

Human serum contains a physiological plethora of bioactive elements naturally released by activated platelets which might have a significant effect on the regeneration of corneal layers by stimulating the cell growth. This mechanism supported the use of human serum eye drops in some ocular diseases associated with dystrophic changes and alterations of the tear film, such as persistent corneal epithelial defects and dry eye syndrome. We focused our effort on potential benefits and limitations of the use of human serum eye drops when conventional therapies failed. We reviewed the recent literature by reporting published studies from 2010 to 2014. Despite the limited evaluated study populations, most of the clinical studies have confirmed that serum eye drop therapy is effective in corneal healing by reducing ocular symptom, particularly during the short-term follow-up. In addition, three recent published studies have shown the efficacy of the serum eye drop therapy in comparison to traditional ones in intractable patients. Besides, reported ongoing clinical studies confirmed the open debate regarding the use of biologic tools for cornea regeneration. Results from these studies might open novel challenges and perspectives in the therapy of such refractory patients.