Predictors of Silicone Tube Intubation Success in Patients with Lacrimal Drainage System Stenosis

Predictors of nasolacrimal duct intubation failure for primary acquired nasolacrimal duct obstruction: a computed tomography-dacryocystography (CT-DCG) study

Background

Making a choice between nasolacrimal duct intubation and dacryocystorhinostomy (DCR) for primary acquired nasolacrimal duct obstruction (PANDO) is an important issue in clinical practice. This study aimed to determine the potential lacrimal sac characteristics that could be used as predictors of unsuccessful intubation for PANDO based on computed tomography-dacryocystography (CT-DCG).

Methods

In this retrospective comparative observational study, we included PANDO patients with a history of failed intubation for nasolacrimal duct obstruction as the intubation failure group and PANDO patients without a history of intubation as the control group. We analyzed the lacrimal sac height, lacrimal sac width, and obstruction site based on CT-DCG, all measured based on several reference levels on axial sections (upper, intermediate, lower level, common canaliculus level, and lowermost contrast level), which were defined according to the contrast and the bony structure.

Results

A total of 114 sides of the PANDO were studied, including 36 in the intubation failure group and 78 in the control group. The intubation failure group showed a smaller lacrimal sac height (11.69±4.59 mm) and width (2.28±1.97 mm, intermediate level) than the control group (14.13±2.92, 3.32±2.02 mm, P=0.005 and 0.012, respectively). The intubation failure group had a higher obstruction site than the control group (P=0.009).

Conclusions

A small lacrimal sac and high obstruction site are predictors of nasolacrimal duct intubation failure in PANDO. For PANDO patients with a small lacrimal sac or a high obstruction position, DCR is recommended as opposed to intubation.

Prospective, randomised clinical trial on the necessity of using a silicone intubarium in the context of endonasal-endoscopic dacryocystorhinostomy (EN-DCR) in patients with postsaccal lacrimal duct stenosis

BACKGROUND

This prospective clinical study evaluates the effect of a silicone stent tube (SST) on the success rate of endonasal-endoscopic dacryocystorhinostomy (EN-DCR) to treat primary acquired nasolacrimal duct obstruction.

METHODS

Patients were randomly assigned to receive EN-DCR with or without SST intubation over a period of 3 months. The surgery was performed using standardized techniques. Patients were assessed at three different timepoints: one day, 12 weeks and 24 weeks after the surgery. The results were compared in order to evaluate statistical differences. Surgical success was determined by means of positive irrigation procedures, as well as by the improvement of symptoms and a high level of patient satisfaction.

RESULTS

A total of 56 randomized cases completed 24 weeks of follow up. 1 Patient dropped out due to malignant genesis of the nasolacrimal duct obstruction. After 24 weeks of follow up no statistically significant differences in levels of epiphora (p > .10) or patency (p > .16) were revealed. Comparisons regarding changes in time did not show levels of significance (p > .28).

CONCLUSIONS

This study could not confirm a statistically significant benefit or disadvantage for SST Insertion in EN-DCR.

Polymers and Biomaterials for Posterior Lamella of the Eyelid and the Lacrimal System

The application of biopolymers in the reconstruction of the posterior lamella of the eyelid and the lacrimal system marks a significant fusion of biomaterial science with clinical advancements. This review assimilates research spanning 2015 to 2023 to provide a detailed examination of the role of biopolymers in reconstructing the posterior lamella of the eyelid and the lacrimal system. It covers the anatomy and pathophysiology of eyelid structures, the challenges of reconstruction, and the nuances of surgical intervention. This article progresses to evaluate the current gold standards, alternative options, and the desirable properties of biopolymers used in these intricate procedures. It underscores the advancements in the field, from decellularized grafts and acellular matrices to innovative natural and synthetic polymers, and explores their applications in lacrimal gland tissue engineering, including the promise of 3D bioprinting technologies. This review highlights the importance of multidisciplinary collaboration between material scientists and clinicians in enhancing surgical outcomes and patient quality of life, emphasizing that such cooperation is pivotal for translating benchtop research into bedside applications. This collaborative effort is vital for restoring aesthetics and functionality for patients afflicted with disfiguring eyelid diseases, ultimately aiming to bridge the gap between innovative materials and their clinical translation.

Bony nasolacrimal duct size and outcomes of nasolacrimal silicone intubation for incomplete primary acquired nasolacrimal duct obstruction

Purpose

To investigate the association between the bony nasolacrimal duct (NLD) size and outcomes of nasolacrimal silicone intubation for incomplete primary acquired nasolacrimal duct obstruction (PANDO).

Methods

Patients who underwent silicone intubation for incomplete PANDO and had undergone facial computed tomography (CT) were included. Surgical success was judged by both epiphora improvement and normalized tear meniscus height (TMH; < 300 μm) on anterior segment optical coherence tomography at 3 months after tube removal. The area, major axis diameter, and minor axis diameter of the elliptic bony NLD sections were measured in 1.0 mm-thick axial CT images. These bony NLD sizes were analyzed for associations with surgical success and TMH normalization.

Results

Eighty-one eyes of 48 patients were investigated. The smallest area and the smallest minor axis diameter were significantly larger in the success group (49 eyes), compared with those in the failure group (median smallest minor axis diameter: 4.7 mm vs. 3.8 mm, P = 0.008, Mann–Whitney U test). There was also a tendency for the TMH normalization rate to significantly increase as the smallest area and the smallest minor axis diameter increased (P = 0.028 and 0.037, respectively, Fisher’s 2 × 4 tests). Under multivariable logistic regression analysis using generalized estimating equation, a larger smallest minor axis diameter was associated with success of the nasolacrimal silicone intubation (odds ratio: 2.481, 95% confidence interval: 1.143–5.384).

Conclusion

Surgical success of the nasolacrimal silicone intubation in incomplete PANDO is associated with a larger smallest minor axis diameter of the bony NLD. This finding will help understand the pathophysiology of surgical failure after nasolacrimal silicone intubation.

Long-term Outcome and Predictors of Silicone Tube Intubation for Patients with Nasolacrimal Duct Obstruction

Purpose: To evaluate the long-term outcome and prognostic factors according to the degree of obstruction after silicone tube intubation in patients with nasolacrimal duct obstruction (NLDO).Methods: From March 2016 to July 2020, the medical records of 145 eyes of 107 patients with NLDO who underwent silicone tube intubation and had been followed for more than 6 months were analyzed retrospectively. The preoperative lacrimal irrigation and degree of obstruction were classified into three groups, and the surgery outcome was also evaluated. Successful surgery was defined as a case in which the epiphora improved, the height of the tear meniscus decreased, and there was no reflux in the postoperative lacrimal irrigation. Risk factors for recurrence were analyzed using a Cox proportional hazards model and Kaplan-Meier survival analysis.Results: Surgery was successful in 99 eyes (68.3%), while recurrence occurred in 46 eyes (31.7%) after silicone tube removal. The average follow-up period was 23.09 months. The recurrence rate was 30.4%, 29.3%, and 50.0% for functional, partial, and total NLDO, respectively, and did not differ significantly (p = 0.300). The risk of recurrence was higher at older age (adjusted hazard ratio [aHR] = 1.079, p < 0.001) and with a history of facial palsy (aHR = 4.031, p = 0.019), and was lower in the functional NLDO group than in the total NLDO group (aHR = 0.368, p = 0.040). In the Kaplan–Meier survival analysis, the total NLDO group differed significantly from the functional NLDO group (log-rank, p = 0.011).Conclusions: Age, a history of facial palsy, and the degree of preoperative obstruction were associated with the prediction of recurrence after silicone tube intubation in patients with NLDO.

Pulled versus Pushed Monocanalicular Silicone Intubation in Adults with Lacrimal Drainage System Stenosis: A Comparative Case Series

Purpose

To compare the success rate and complications of pulled versus pushed monocanalicular intubation in adults with incomplete lacrimal drainage system obstruction (lacrimal drainage system stenosis).

Methods

Patients with lacrimal drainage system stenosis (Munk grade ≥3), including both nasolacrimal duct (NLD) stenosis and common canalicular stenosis, were recruited in this prospective comparative case series. Patients underwent probing and either Monoka (51 eyes) or Masterka (48 eyes) intubation under general or local anesthesia. Tubes were removed 4–14 weeks after the procedure. Six months after tube removal, Munk grades 0 and 1 were defined as a complete success, Munk grade 2 was defined as a partial success, and Munk grade ≥3 was defined as failure. All complications were recorded.

Results

Ninety-nine eyes from 89 patients with lacrimal drainage system stenosis who underwent either Monoka (51 eyes) or Masterka (48 eyes) intubation were included. The mean (SD) age of the patients was 55.4 (12) years in the Monoka group and 53.5 (12.9) in the Masterka group. Groups were matched on demographics. Masterka intubation could not be performed in one eye. Complete and partial successes were observed in 52.9% (27/51) and 17.6% (9/51) of eyes in the Monoka group and 42.6% (20/47) and 12.8% (6/47) of eyes in the Masterka group, respectively (p=0.29). There was a trend toward a higher total success rate in patients with NLD stenosis treated with Monoka 66.7% (26/39) than Masterka 45.5% (15/33) intubation (p=0.07). This trend also existed in patients with common canalicular stenosis (83.3% (10/12) vs. 76.6% (11/14), p=0.75). Age, sex, bilateral involvement, and duration of intubation did not have a significant impact on the success rate. Early tube loss, slit puncta, and temporary superficial punctate keratopathy were observed complications.

Conclusion

Intubation with the pulled monocanalicular silicone tube was associated with a slightly but not significantly higher success rate in adults with lacrimal drainage system stenosis. Patients with NLD stenosis may achieve better results with pulled silicone tubes.

Successful Reposition of Prolapsed Silicone Tube Using Hole and Lacrimal Probe Method

Purpose

Silicone tube intubation is the most common method for treatment of nasolacrimal drainage disorder or repair of lacerated canaliculus. However, some cases are prolapsed earlier than expected, subsequently affecting the success rate of silicone tube intubation. The author introduced a successful reposition of the prolapsed silicone tube.

Methods

This study is a retrospective case series of 11 patients who were treated with reposition of prolapsed silicone tube using hole and lacrimal probe method. In all cases, the tubes were prolapsed within 2 months after the first surgery due to careless rubbing of the medial canthus by the patient. In all 11 cases, the development of a biofilm on tube was not observed at the time when the tube was prolapsed. All patients underwent immediate reposition of prolapsed tube without local anesthesia in the outpatient operating room on the day they visited.

Results

In all 11 cases, the prolapsed silicone tube was repositioned without any complications using this hole and lacrimal probe method. At 6-month follow-up examination, all patients presented with a well-positioned silicone tube up to the day of extubation without replacing it with a new silicone tube.

Conclusions

This hole and lacrimal probe method is effective for the repositioning of prolapsed silicone tube after bicanalicular intubation of lacrimal system. This procedure includes easy performance in a short time and without local anesthesia in the outpatient operating room.

Assessment of conjunctival flora in eyes with lacrimal passage obstruction before and after successful dacryoendoscopic recanalisation

BACKGROUND

To investigate conjunctival bacterial flora in eyes with lacrimal passage obstruction before and after dacryoendoscopic recanalisation with lacrimal tube intubation.

METHODS

One-hundred fifty eyes with lacrimal passage obstruction that were successfully treated by dacryoendoscopic recanalisation were enrolled. Conjunctival sampling was done for each eye before and 4 months after surgery. The lower fornix was rubbed by a sterile cotton swab, and the collected samples were cultured with several agar plates. Colonies were differentiated and enumerated by standard bacteriological laboratory techniques.

RESULTS

Positive bacterial growth was detected in 42.0% of all the samples before surgery, and the positivity rate significantly decreased to 26.0% after surgery (p=0.0051). The number of strains detected also decreased from 20 before surgery to 9 after surgery, especially pathogenic microorganisms decreased. In addition, drug-resistant bacteria such as penicillin-resistant Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus were detected in nine eyes before surgery but were detected only in one eye after surgery. Coagulase-negative Staphylococci and Corynebacterium spp., which are common in normal conjunctival flora, accounted for 46.5% of all the isolates before surgery and 80.9% after surgery, showing a significant increase in the rate after surgery (p<0.0001).

CONCLUSIONS

This study showed that physiological recanalisation of lacrimal passage after dacryoendoscopic surgery significantly decreased the culture positivity rate of conjunctival sac and the number of microorganism strains detected. It also decreased the number of potentially pathogenic and drug-resistant bacteria and increased the percentages of indigenous bacteria, causing the normalisation of conjunctival flora.

[Recanalisation by Probing with a Bicanalicular Silicone Tube (Oggel Silicone Intubation) in Patients with Acquired Lacrimal Stenosis]

OBJECTIVES

Recanalisation and bicanalicular splinting with silicone tube is one therapeutic option for acquired lacrimal duct stenosis, and restenosis is frequently achieved. The aim was to determine the therapeutic success of Oggel silicone intubation after lacrimal syringing and probing. We also analysed other characteristics of the complaint and compared the therapeutic success with published results.

METHODS

Therapeutic success was defined as subjective absence of complaints. Other complaint features - directly after explantation of the Oggel tube, one month after explantation and one year after explantation - were retrospectively collected by a patient questionnaire, and a questionnaire for the attending ophthalmologist. These were completed with information from the patient's file. We included 82 procedures performed at the Dept. of Ophthalmology, University of Ulm, between 2006 and 2015. Statistical testing of the impact of risk factors on therapeutic success was performed, using logistic regression analysis and the Mann-Whitney U test. Subgroups were compared using Pearson-Chi-square and Fisher's exact tests and a Kaplan-Meier analysis was also performed.

RESULTS

Therapeutic success could be documented in 80.8% of patients after explantation of the Oggel tube, in 61.6% of patients after one month and in 42.5% of patients at one year (n = 82). There were no significant differences between the subgroups of stenosis localisation, or the patients' age or sex. There was also no significant influence of the patient's age, the preoperative duration of complaints or risk factors predisposing for lacrimal duct stenosis. For the observation period of one year, the Kaplan-Meier analysis gave a probability of complaint-freeness of 52.2% for the patient group, as well as a mean duration of the complaint-free period of 34.2 weeks.

CONCLUSION

The results allow a prognostic assessment of the therapeutic success in the absence of significant differences in the subgroups. The therapeutic success of bicanalicular silicone intubation with the Oggel tube was in the lower third of comparable studies. The results conform to the observation that there is a progressive decline of therapeutic success. The comparison of the literature turned out to be methodically more difficult due to differences in study characteristics. Standardisation would make sense for future studies.

Nasolacrimal stent with shape memory as an advanced alternative to silicone products

Epiphora is the overflow of tears typically caused by obstruction or occlusion of the nasolacrimal duct. More attention is required to address this global health issue owing to the increase in air pollution. Implantation of a silicone stent is the preferred treatment for epiphora; however, introducing a silicone stent into a narrow duct with complex geometry is challenging as it requires guidance by a sharp metal needle. Additionally, silicone can cause adverse reactions such as biofilm formation and tear flow resistance due to its extreme hydrophobicity. To overcome these problems, in this study we developed a new type of biocompatible shape memory polymer (SMP) stent with elasticity capacity for self-expansion. First, SMPs in the form of x%poly(ε-caprolactone)-co-y%poly(glycidyl methacrylate) (x%PCL-y%PGMA) were synthesized via ring opening polymerization by varying the molar ratio of PCL (x%) and PGMA (y%). Second, the shape memory and mechanical properties were tuned by controlling the crosslinking degree and concentration of x%PCL-y%PGMA solution to produce a test type of SMP stent. Lastly, this 94%PCL-06%PGMA stent exhibited more standout critical functions in a series of in vitro and in vivo experiments such as a cell growth-supporting level of biocompatibility with nasal epithelial cells without significant inflammatory responses, better resistance to biofilm formation, and more efficient capacity to drain tear than the silicone control. Overall, 94%PCL-06%PGMA can be suggested as a superior alternative to the currently used materials for nasolacrimal stents. STATEMENT OF SIGNIFICANCE: Silicone intubation (stenting) has been widely used to treat nasolacrimal duct obstruction, however, it can cause adverse clinical effects such as bacterial infection; presents procedural challenges because of the curved nasolacrimal duct structure; and shows poor drainage efficiency stemming from the highly hydrophobic nature of silicone. In this work, we describe an innovative shape memory polymer (SMP) as a superior alternative to conventional silicone-based materials for nasolacrimal duct intubation. We demonstrate the clear advantages of the SMP over conventional silicone, including a much higher drainage capacity and superior resistance to bacterial infection.

Novel Use of Silicone Sheets for Immediate Implant Placement in Fresh Molar Extraction Sockets

In the recent years, the immediate placement of dental implants into fresh extraction sites has become an acceptable treatment approach. However, immediate molar implant placement presents specific challenges because of the anatomical and physiologic limitations. Such implant surgeries commonly require procedures that use a barrier membrane to generate bone and soft tissue or one that seals the molar extraction socket through a coronally advanced flap. Here, as an alternative, we report a method for treating molar extraction socket wounds in the hard and soft tissues after immediate placement of an implant using a silicone sheet.

Pathological changes of the nasolacrimal duct in rabbit models of chronic dacryocystitis: correlation with lacrimal endoscopic findings

PURPOSE

The aim of this study was to explore the pathological changes of the nasolacrimal duct in rabbits with experimentally induced obstructive dacryocystitis in correlation with lacrimal endoscopic findings.

METHODS

The rabbit model of obstructive dacryocystitis was created by injecting 0.15 ml of self-curing resin into the lacrimal duct. The control group received 0.15 ml of normal saline. Within 16 weeks after the obstructive, lacrimal endoscopy and pathological examination of the nasolacrimal duct were conducted at different time points of 1, 2, 4, 8, and 16 weeks.

RESULTS

In the control group, lacrimal endoscopy revealed pink and smooth mucosa; and the pathological analysis revealed an epithelial layer that was composed of superficial columnar cells and a deep basal epithelial layer. The experimental rabbits showed clinical manifestations of obstructive dacryocystitis a week after the injection of self-curing resin. At weeks 1 and 2, the lacrimal endoscopy showed mucosal hyperemia and hemorrhagic spots on the nasolacrimal duct; and the pathological features included epithelial cell swelling and inflammatory cell infiltration. At weeks 4 and 8, the experimental group showed alternatively red and white mucosa under the lacrimal endoscopy, and the pathological features included proliferative epithelium accompanied by papillary hyperplasia. At week 16, the experimental group showed pale and coarse mucosa and white membrane-like layer covering the mucosal surface, and the pathological features included epithelial necrosis, squamous metaplasia, and sub-epithelial fibrosis.

CONCLUSION

The mucosa of the nasolacrimal duct showed different pathological features at different time points after lacrimal duct obstruction, which was well correlated with the endoscopic findings. It is possible to predict the pathological stages by the endoscopic observation in NLOD patients.