Etiopathogenesis of primary acquired nasolacrimal duct obstruction (PANDO)

Pre-Operative Planning of a DCR Surgery Using Virtual Reality

PURPOSE

To assess a novel Virtual Reality (VR) tool designed to enhance understanding of the nasal anatomy in patients eligible for DCR surgery.

METHODS

Preoperative Computed Tomography (CT) scans of the orbit were obtained and loaded as DICOM (Digital Imaging and Communications in Medicine) files onto the D2P software (3D Systems Inc. Littleton, CO) for tissue segmentation and 3D model preparation. Segmentation was performed on several anatomical structures, including the skull, lacrimal sac, nasal septum, inferior and middle turbinate. The resulting 3D model was visualized using a VR headset. After completing the segmentation procedure, ten cases were evaluated by a panel of six surgeons, including both senior and resident physicians from ENT and oculoplastic specialties.

RESULTS

The dataset under examination comprised images from 10 preoperative CT scans of the orbits of patients eligible for Endo-DCR. When evaluating the CT using the VR tool, in 73.3% of the cases ENT surgeons were right about the side of pathology, while only 43.3% ophthalmologists were right (chi-square, p = .018). In 72.8% of the cases ENT surgeons were evaluated right that there is a septum deviation, while only in 47.2% of the cases the ophthalmologists were right (chi-square, p = .094).When evaluating the CT using the VR tool, in 60% of the cases consultants were right about the pathology, while 57.7% of the residents were right (chi-square, p = .853). In 81.7% of the cases consultants were evaluated right that there is a septum deviation, while only in 58.3% of the cases the ophthalmologists were right (chi-square, p = .198).

DISCUSSION

ENT surgeons, as well as consultants, interpreted the CT better than the ophthalmologists and residents. Surprisingly, the VR system did not help them to interpret the CT better. Further, more extensive studies should be done to build a VR system that assists in the correct interpretation of the preoperative CT before DCR surgery as well as during DCR surgery.

Dry eye and decreased tear film stability in primary acquired nasolacrimal duct obstruction patients

PURPOSE

Exploring the prevalence of dry eye (DE) and the changes of tear film stability in patients with primary acquired obstruction of the nasolacrimal duct (PANDO).

METHODS

In this cross-sectional, observational study, 370 eyes in 223 patients with PANDO were assessed. The ocular surface disease index (OSDI) was used to evaluate ocular surface symptoms, and the Keratograph 5M non-invasive ocular surface analyser was used to assess ocular surface parameters. According to the TFOS DEWS II criteria, patients with OSDI ≥ 13 and NIKBUT < 10 s were diagnosed with DE.

RESULTS

Of the 223 PANDO patients, 65 (29.1%) met the diagnostic criteria for DE. Compared with patients without DE, PANDO patients with DE were significantly older (p < 0.001), had a longer duration of epiphora (p = 0.023), and more likely to have a positive regurgitation on pressure over the lacrimal sac (ROPLAS) sign (p = 0.003). Multifactorial analysis showed that older age, positive ROPLAS and hypertension were significant independent predictors of DE (p < 0.05). Among the 147 unilateral PANDO patients without DE, the TMH, NIKBUT-first, NIKBUT-average and bulbar erythema scores were significantly higher in the PANDO sides.

CONCLUSIONS

This study illustrated the prevalence of DE in PANDO patients was 29.1% and DE is more likely to occur in those who are older, have hypertension and are positive for ROPLAS. In addition, in patients with unilateral nasolacrimal duct obstruction, a decrease in tear film stability was observed in the healthy eye.

Dacryocystitis in a Patent Nasolacrimal Drainage System: A Literature Review

INTRODUCTION

Acute dacryocystitis is an acute infection and the lacrimal sac secondary to pathogenic microorganism growth within the stagnant fluid in the lacrimal sac secondary to nasolacrimal duct obstruction.

METHODS

A literature review was conducted on the PubMed database using the following search terms "dacryocystic retention" and "dacryocystitis" or "dacryolith" or "lacrimal duct" or "pseudo-dacryocystitis".

RESULTS

The literature review suggests that dacryocystitis in a patent nasolacrimal drainage system can stem from diverse causes including the mechanical impaction by dacryoliths, viral infections and anatomical variations. It is believed that these causes lead to transient obstruction to the nasolacrimal excretory system predisposing to secondary infections. Idiopathic temporary dacryocystic retention is also highlighted in this review.

CONCLUSIONS

This review broadens the understanding of dacryocystic retention and highlights the need for careful diagnosis and tailored treatment plans, particularly in cases deviating from the traditional etiological pathways.

Update on lacrimal apparatus dysfunction associated with differentiated thyroid cancer after I-131 therapy

PURPOSE

The most prevalent lacrimal apparatus dysfunctions associated with differentiated thyroid cancer(DTC) after I-131 therapy are dry eye and nasolacrimal duct obstruction(NLDO), leading to ocular discomfort and lower quality of life for patients. It is crucial to diagnose and manage lacrimal apparatus dysfunction associated with I-131 therapy for DTC. Therefore, this review aims to comprehensively summarize and analyze the advances in mechanisms and therapeutic options underlying lacrimal apparatus dysfunction induced by I-131 therapy for DTC.

METHODS

A comprehensive search of CNKI, PubMed, and Wed of Science was performed from the database to December of 2023. Key search terms were "Thyroid cancer", "I-131", "Complications", "Dry eye", "Epiphora", "Tear", "Nasolacrimal duct" and "NLDO".

RESULTS

The research indicates that I-131 therapy for DTC causes damage to the lacrimal glands and nasolacrimal duct system, resulting in symptoms such as dry eye, epiphora, and mucoid secretions. Moreover, recent research has focused on exploring relevant risk factors of the condition and experimental and clinical treatments. However, there is some controversy regarding the mechanisms involved, whether it is due to the passive flow of I-131 in tears, active uptake of I-131 by the sodium-iodide symporter (NIS) in the lacrimal sac and nasolacrimal duct, or secondary metabolic and hormonal disturbances caused by I-131.

CONCLUSION

It is crucial for early detection and preventive measures by ophthalmologists and the need for further studies to elucidate the mechanisms underlying the disease.

Are inflammation-related diseases risk factors for primary acquired nasolacrimal duct obstruction? A large scale, national case-control study

PURPOSE

To evaluate the incidence and risk factors for inflammatory conditions among patients with primary acquired nasolacrimal duct obstruction (PANDO).

METHODS

A retrospective case-control study was conducted among patients of Clalit Health Services (CHS) in Israel from 2001 to 2022. For each case, three controls were matched among all CHS patients according to year of birth, sex, and ethnicity. Differences in demographic characteristics, ocular surface, eyelid, upper airway, and systemic diseases were assessed between the groups, and odds ratios (OR) were calculated.

RESULTS

A total of 60,726 patients diagnosed with PANDO were included. The average age of PANDO patients was 63 ± 18 years, 63% were female. Significant associations were found between PANDO and various ocular surface and eyelid conditions, including chronic conjunctivitis (OR 2.96, 95% CI [2.73-3.20]), vernal keratoconjunctivitis (OR 2.89, 95% CI [2.45-3.29]), and blepharitis (OR 2.75, 95% CI [2.68-2.83]). There was a significant association with various upper airway conditions, including rhinitis (OR 1.62, 95% CI [1.58-1.66]), chronic sinusitis (OR 1.71, 95% CI [1.62-1.80]), and deviated nasal septum (OR 1.76, 95% CI [1.69-1.84]). Association was also observed with systemic conditions, including asthma (OR 1.34, 95% CI [1.27-1.41]) and atopic dermatitis (OR 1.36, 95% CI [1.32-1.41]).

CONCLUSION

Ocular surface, eyelid, upper airway, and systemic inflammatory-related diseases were found to be associated with PANDO, supporting the theory that inflammation has a prominent role in the pathophysiology of PANDO.

Clinical characteristics and cytological changes in mucinous obstruction diagnosed by dacryoendoscopy

To analyze the clinical characteristics of mucinous obstruction diagnosed by dacryoendoscopy and compared the cytological changes with membranous obstruction using a modified liquid-based thin prep cytology method. A retrospective chart review was conducted on 53 eyes of 51 patients with mucus obstruction based on dacryoendoscopic findings from January 2022 to October 2022. Liquid-based thin-prep cytology was performed by irrigating the inside of the nasolacrimal drainage system with saline during dacryoendoscopy-guided silicone tube intubation. Pathological findings were analyzed through a comparison of mucinous obstruction with membranous obstruction as determined by dacryoendoscopic findings. The modified liquid-based thin prep cytology technique had a higher cytology detection rate across all cases. Mucinous obstruction exhibited a significantly higher number of successful canalicular irrigation test cases compared to membranous obstruction. In mucinous obstruction, epithelial squamous cells were more frequently detected in pre-sac obstruction, whereas columnar epithelial cells were predominant in post-sac obstruction. Inflammatory cells showed a stronger correlation with primary change and post-sac obstruction. Bacterial colonies were observed exclusively in cases of mucinous obstruction. The use of a modified liquid-based thin prep cytology method enables the examination of histopathological changes in the lacrimal passage in primary acquired nasolacrimal duct obstruction (PANDO), particularly in cases of mucinous obstruction, without the need for invasive biopsies. These findings enhance the understanding of the etiopathogenesis of mucinous obstruction, complementing knowledge of membranous obstruction in PANDO.

Outcomes of Endoscopic Endonasal Dacryocystorhinostomy in Glaucoma Patients

BACKGROUND

Anti-glaucoma eye drops have been investigated due to their production of fibrotic changes on the conjunctival surface, undermining the functioning of the upper lacrimal drainage system. We aimed to assess whether these effects may impair the effectiveness of endoscopic endonasal dacryocystorhinostomy (EE-DCR).

METHODS

This is a single-center observational retrospective study on EE-DCR via a posterior approach. Resolution of epiphora and dacryocystitis were analyzed after 1 (T1) and 6-months (T2) from surgery. Surgical success was defined as anatomical (patency at irrigation, no recurring dacryocystitis) or complete (zeroing of Munk score).

RESULTS

Twenty patients (32 sides) were enrolled. Preoperatively, 93.75% (n = 30/32) presented severe (Munk 3-4) epiphora and 68.75% (n = 22/32) recurrent dacryocystitis. At T1, 50.0% (n = 16/32) were referred with residual epiphora (Munk ≥ 1) and 18.75% (n = 6/32) dacryocystitis. At T2, 31.25% (n = 10/32) still complained of epiphora (Munk ≥ 1) and 6.25% (n = 2/32) dacryocystitis. Difference of outcomes at aggregate and paired timepoints (except for T1 versus T2) resulted in statistical significance (p < 0.05). At T2, 22 (68.75%) complete, 8 (25.0%) anatomical successes and 2 (6.25%) surgical failures were observed.

CONCLUSIONS

Despite the chronic uptake of anti-glaucoma eye drops, EE-DCR guaranteed high rates of clinical relief from epiphora and remarkable decreases in the rates of recurrent dacryocystitis.

CT-Measured Angulation Between the Frontal Bone and Bony Nasolacrimal Duct: Variations in Obstructed and Healthy Lacrimal Ducts

PURPOSE

The aim of this study was to analyze the characteristics of CT-measured intersection angle (FB-BNLD) between the frontal bone and bony nasolacrimal duct and to provide suggestions for treating primary acquired nasolacrimal duct obstruction (PANDO) patients in West China.

METHODS

Three hundred and nine participants' CT were, respectively, evaluated with RadiAnt DICOM Viewer. We defined the FB-BNLD angle >0° as the anterior type and the FB-BNLD angle ≤0° as the posterior type.

RESULTS

The mean FB-BNLD was -2.52° (95% CI, -3.16° to -1.88°) across all participants, of whom 37.2% were of the anterior type and 62.8% of the posterior type. Approximately 65.0% of the female patients had a posterior FB-BNLD type, and 54.2% of the male patients had an anterior FB-BNLD type (p = .002). Posterior FB-BNLD was the dominant type in the PANDO and control groups (p = .011), and the angle of FB-BNLD was statistically different in both groups (PANDO group, -2.54° to -0.71°; control group, -4.42° to -2.67°; p < .001). Among the male participants, the type of FB-BNLD differed between the two groups (p = .036), with differences in the angle of FB-BNLD (PANDO group, 0.59° to 5.13°; control group, -4.08° to 1.89°; p = .034). There was no difference in the type of FB-BNLD in female participants between the two groups (p = .051).

CONCLUSION

The present study revealed individual differences in the type of FB-BNLD, with anterior-type majority in males and posterior-type dominance in females. Evaluating the FB-BNLD type on CT can provide a fast method for knowing the nasolacrimal duct condition during planning for lacrimal manipulation.

Comparing the diagnostic accuracy of MR dacryocystography (MRD) and dacryoscintigraphy (DSG) in NLDO-related acquired epiphora

PROPOSE

This study aimed to compare the diagnostic accuracy of MR dacryocystography (MRD) and dacryoscintigraphy (DSG) in the diagnosis of acquired epiphora related to NLDO. A total of 15 patients with acquired epiphora and suspected NLDO were included in this study.

METHODS

All patients underwent MRD and DSG examinations. MRD was performed using a 3-Tesla magnetic resonance imaging (MRI) scanner, while DSG involved injection of a radiotracer into the lacrimal drainage system followed by DSG. The results of both imaging methods were compared with the reference standard that was a combination of clinical examination findings and surgical exploration.

RESULTS

The results of this study showed that no abnormal findings were observed in MR-DCG in patients before the Valsalva maneuver. However, after the Valsalva maneuver, stenosis/obstruction at the canal surface was observed in all 15 patients diagnosed by DSG, giving a sensitivity of 100% for canal stenosis. Moreover, the results revealed that among these 15 patients, 9 showed stenosis or simultaneous obstruction at the level of the canal and lacrimal sac, but MR-DCG showed these lesions in only 9 patients, giving a sensitivity of 60%. The specificity of MRD and DSG were 85% and 76.7%, respectively. There was a statistically significant difference in the sensitivity of MRD and DSG (p < 0.05).

CONCLUSION

This study demonstrated that MRD has a higher diagnostic accuracy in the diagnosis of acquired epiphora associated with NLDO compared to DSG. MRD showed significantly higher sensitivity and specificity than DSG. Therefore, MRD can be considered as the preferred imaging modality in the diagnosis of acquired epiphora due to NLDO. By accurately identifying the underlying cause of NLDO, MRD can help determine the most appropriate treatment approach for patients and lead to better outcomes.

Evaluation of primary acquired nasolacrimal duct obstruction: Comparison of CT-DCG and dacryoendoscopy in accurately localizing the lacrimal drainage obstructions

OBJECTIVE

To correlate and evaluate the power and limitations of CT-DCG in determining the level and type of lacrimal duct obstruction in comparison to dacryoendoscopy in patients clinically suspected to be having partial or complete primary acquired nasolacrimal duct obstruction (PANDO).

METHODS

A retrospective chart review was performed on 1232 lacrimal drainage systems of 957 patients who suffered from primary acquired nasolacrimal duct obstruction (PANDO) at Shanghai Ninth People's Hospital. Patients were examined with CT-DCG and correlated with dacryoendoscopy and the findings of clinical examination.

RESULTS

Of the studied patients, 173 were men and 784 were women with an age range of 18-93 years. Of the 1232 lacrimal pathways, good CT-DCG images could be obtained in 980 cases and dacryoendoscopy in 957 cases. Of these complete obstructions were noted in 81% (794/980), and partial obstructions were identified in 19% (186/980) with CT-DCG. CT-DCG and dacryoendoscopy showed 68.4% agreement for the type of the obstruction and 63% for the level of the obstruction. The majority of the obstructions occurred at the sac-duct junction (62.5%) followed by the upper half of the nasolacrimal duct (27.5%). There was a significant difference in the correlation of the obstruction type with age group and with the duration of symptoms. As the duration of symptoms increased, the proportion of complete lacrimal duct obstructions as shown on CT-DCG images increased and the proportion of incomplete obstruction decreased (p = 0.015).

CONCLUSIONS

The junction of lacrimal sac and nasolacrimal duct was the most common obstruction site. Age and the duration of symptoms influenced the type of obstruction noted. The degree and level of agreement between the investigations was moderate. A combination of CT-DCG and Dacryoendoscopy could together identify the location more accurately.