Diversity in Lacrimal Pathway Morphology Among Patients with Congenital Nasolacrimal Duct Obstruction.

Purpose: This prospective observational study aimed to explore the diversity in lacrimal pathway morphology among patients with congenital nasolacrimal duct obstruction (CNLDO) by examining dacryocystography (DCG) images. Patients and Methods: The study included 64 patients who underwent DCG before undergoing general anesthesia probing for unilateral CNLDO. Several parameters were measured from the lateral view of the DCG images: (1) the lacrimal sac (LS) and the nasolacrimal duct (NLD) angle, (2) the angle formed by the superior orbital rim (SOR), LS, and the NLD, (3) LS length, and (4) bony NLD length. Additionally, frontal views of the DCG images were utilized to measure (5) LS-NLD angle and (6) LS angle concerning the midline. Results: The average age of the patients was 34.3 months. The mean ± standard deviation of the measurements of the above parameters was (1) -1.2° ± 16.5° (range: -44.6° ± 46.6°), (2) -5.0° ± 10.3° (range: -24.0° ± 19.0°), (3) 10.2 ± 2.4 mm (range: 6.5-16.0 mm), (4) 8.0 ± 2.5 mm (range: 3.1-14.8 mm), (5) 15.6° ± 11.2° (range: -16.8° ± 41.0°), and (6) 15.1 ± 5.2° (range: 3.3°-29.8°). All parameters, except for parameter (3), conformed to a normal distribution. Conclusion: This study provides valuable anthropometric data derived from DCG images, highlighting the substantial variability in lacrimal pathway morphology among patients with CNLDO. Furthermore, anatomical constraints made probing with a straight metal bougie anatomically infeasible in 25.0% of the patients included in this study.

Understanding the morphology of the lacrimal pathway is crucial for the successful probing treatments in patients with congenital nasolacrimal duct obstruction (CNLDO). This study represents an initial effort to quantify anthropometric parameters of the lacrimal drainage system through dacryocystography images, specifically aiming to highlight the limitations of blind probing procedure. The results underscore significant variations in the morphology of the lacrimal drainage system among patients, which could impact diagnostic approaches and treatment strategies. Additionally, the findings suggest that patients with CNLDO who do not respond to blind probing may have underlying anatomical complexities. Therefore, rather than relying on repeated blind probing, employing dacryoendoscopy-guided probing under direct visualization could offer a more effective therapeutic alternative for complicated cases of CNLDO.

Clinical utility of digital radiography dacryocystography for preoperative assessment in nasolacrimal duct obstruction prior to endoscopic dacryocystorhinostomy.

Purpose: To evaluate the clinical usefulness of digital radiography dacryocystography in patients with primary acquired nasolacrimal duct obstruction prior to endoscopic dacryocystorhinostomy. Methods: All dacryocystography images from 129 patients with primary acquired nasolacrimal duct obstruction were analyzed. Each group was assessed for postoperative epiphora severity using Munk's score via telephone follow-up three years post-surgery. Receiver operating characteristic (ROC) curve was plotted to obtain a suitable cutoff value of the transverse diameter of the lacrimal sac (LS), used to categorize LS size into small (≤4.350 mm) and large (>4.350 mm). Results: Analysis of the transverse diameter of the LS among 129 patients showed a negative correlation between it and Munk's score (r = -0.282, p = 0.001). There was a statistical difference between the surgical outcomes and the sizes of the LS (p = 0.041). The ROC curve analysis showed that the transverse diameter of the LS at 4.350 mm was the ideal cutoff value for the outcome of endoscopic dacryocystorhinostomy, with a sensitivity of 42.2 %, and specificity of 92.3 %. After adjusting for the age and sex, the small LS was associated with an increased risk of postoperative failed outcome (adjusted odds ratio [95 % CI]: 8.628 [1.074, 69.335]). Conclusion: The small LS was independently associated with the failed surgical outcome. Furthermore, the preoperative measurement of the LS transverse diameter serves as one of the reliable predictors for postoperative epiphora severity.

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.

A Pilot Study of Dynamic Magnetic Resonance Dacryocystography Imaging to Assess Functional Epiphora.

OBJECTIVE: To evaluate dynamic magnetic resonance dacryocystography (MRDCG) in eyes with functional epiphora. METHODS: We included prospective eyes with epiphora if no alternative cause was found on clinical examination, were patent on syringing, had no obstruction or stenosis on DCG, and had an abnormal DSG. MRDCG was performed to qualitatively assess for block or patency and quantitatively measure tear transit time. We compared measurements to asymptomatic fellow eyes and to historical reference values from asymptomatic eyes. RESULTS: We included 26 symptomatic eyes of 19 patients (median age 63 years). There was a block on MRDCG in 18 (69%) eyes and patency in 8 (31%) eyes. The block occurred at the sac-nasolacrimal duct (NLD) junction in 9 (50%), proximal NLD in 5 (28%), mid-NLD in 1 (5.6%), and distal NLD in 1 (5.6%) eye(s). No contrast was observed in the lacrimal system in two eyes. For eyes patent on MRDCG, median times to the sac, NLD, inferior meatus, first 25%, and first 50% of the fundus-to-nose distance (FND) were 22, 54, 118, 34, and 84 s, respectively. Times to the sac, NLD, and to fill the first 25% and 50% of the FND were significantly longer than historical values from asymptomatic lacrimal systems (p = 0.017, 0.050, 0.035, 0.017, respectively). CONCLUSION: MRDCG shows a high rate of block in functional epiphora. However, DSG and MRDCG results may not always correlate. The improved temporal resolution of this emerging modality may be advantageous in the critical first 2 min of tear transit.

Comparison of the surgical outcomes of endoscopic dacryocystorhinostomy in chronic dacryocystitis with or without previous bicanalicular silicone tube intubation.

AIMS: To compare the outcomes of endoscopic dacryocystorhinostomy (En-DCR) in chronic dacryocystitis (CD) with or without previous bicanalicular silicone tube intubation (BSTI), and investigate whether previous BSTI influenced postoperative outcomes. METHODS: We conducted a retrospective review of medical records of CD patients (group A) who had previously undergone BSTI for nasolacrimal duct stenosis and an age- and sex-matched control group of CD patients (group B) without previous intubation receiving En-DCR from November 2017 to January 2022. Sixty-one patients (61 eyes) were included in group A and age- and sex-matched 122 patients (122 eyes) in group B. Dacryocystic parameters were measured by computed tomography-dacryocystography and surgical findings were recorded during surgeries. The surgical success rates of the two groups were compared at 12 months post-operation. RESULTS: The mean horizontal, sagittal, and vertical lengths were 6.06 ± 1.24, 6.03 ± 1.44, and 8.05 ± 2.00 mm, respectively, in group A and 6.33 ± 1.25, 6.26 ± 1.19, and 10.40 ± 2.45 mm, respectively, in group B. There were no differences in the horizontal or sagittal parameters between the two groups. The vertical parameter in group A was significantly lower than that in group B. Scar formation in the sac was observed in 54 patients in group A but was absent in group B. At 12 months postoperatively, the anatomical and functional success rates were 88.52 % and 85.25 %, respectively, in group A and 92.62 % and 89.34 %, respectively, in group B, with no difference between the two groups. CONCLUSION: Previous BSTI reduced dacryocyst vertical parameter and caused dacryocyst scar formation but did not affect postoperative En-DCR efficacy.

Investigation of lacrimal sac space-occupying lesions using color doppler ultrasound, computed tomography, and computed tomography dacryocystography.

AIM: To observe the imaging features of color Doppler ultrasound (CDU) and computed tomography (CT) or computed tomography dacryocystography (CT-DCG) in different types of lacrimal sac space-occupying lesions (SOLs). METHODS: This retrospective case series study included 21 patients with lacrimal sac SOLs who underwent lacrimal sac surgery between January 2018 and March 2022. The imaging features of CDU and CT or CT-DCG in these patients were extracted from the examination cloud system. The images were observed and analyzed. RESULTS: The detection rate of lacrimal SOLs between CDU (21/21, 100%) and CT or CT-DCG (20/21, 95.2%) had no statistically significant difference (P=1.0). CDU could detect the blood flow signals in all SOLs except mucocele and mucopeptide concretion. Among them, polyps had characteristic imaging changes on CDU and CT-DCG. The mucoceles and mucopeptide concretions had characteristic imaging changes on CDU, which could provide more information for differential diagnosis. CONCLUSION: The morphology and internal blood flow signals of lacrimal sac SOLs can be observed using CDU. CT or CT-DCG has advantages in observing structural damage around the lacrimal sac mass. Therefore, CDU may be used as a routine examination to exclude lacrimal sac SOLs before dacryocystorhinostomy in the absence of preoperative CT or CT-DCG.

Topographic and anatomical features of the nasolacrimal duct obstruction due to radioiodine treatment.

PURPOSE: To investigate the topographic and anatomical features of secondary acquired nasolacrimal duct obstruction (SALDO) due to radioiodine therapy. METHODS: Dacryocystography-computed tomography (DCG-CT) scans of the nasolacrimal ducts in 64 cases with SALDO due to radioiodine therapy and in 69 cases with primary acquired nasolacrimal duct obstruction (PANDO) were studied. The anatomical site of obstruction was located, and morphometric characteristics of the nasolacrimal ducts were calculated: volume, length, and average sectional area. The statistical analysis was performed using the t-criterion, ROC analysis, and the odds ratio (OR). RESULTS: The mean nasolacrimal section area was 10.7 ± 0.8 mm2 in patients with PANDO and 13.2 ± 0.9 mm2 in patients with SALDO due to radioiodine therapy (p = 0.039); the AUC value in ROC analysis for this parameter was 0.607 (p = 0.037). The development of "proximal" obstruction including lacrimal canaliculi obstruction and obstruction at the site of the lacrimal sac was 4.076 times more likely (CI: 1.967-8.443) in patients with PANDO than in patients with SALDO due to radioactive iodine exposure. CONCLUSIONS: By comparing CT scans of the nasolacrimal ducts, we observed that in SALDO obstruction due to radioactive iodine therapy is predominantly "distal," while in PANDO it is more often "proximal." The development of obstruction within SALDO is followed by more pronounced suprastenotic ectasia.

Accuracy of the Lacrimal Syringing Test in Relation to Dacryocystography and Dacryoendoscopy.

Purpose: This study aimed to evaluate the accuracy of the lacrimal syringing test (syringing) in relation to dacryocystography (DCG) and dacryoendoscopy (DE) in lacrimal pathway (LP) obstruction. Methods: We retrospectively reviewed 101 patients (188 LPs) who underwent syringing, cone-beam computed tomography (CBCT)-DCG, and DE to diagnose the degree and site of LP obstruction. The degree of obstruction was classified into patent, partial obstruction, and complete obstruction. The degree of LP obstruction was determined by combining the findings of DE and CBCT-DCG and was designated as DCG+DE. When differentiating complete or partial obstruction on DE was uncertain, complete or partial obstruction was assigned if the DCG showed evidence of contrast media obstruction or passage, respectively. The consistency between syringing and DCG+DE was evaluated by calculating the weighted kappa coefficient. Results: The sensitivity and specificity of syringing were 94% and 89%, respectively. The weighted Cohen's kappa value of agreement between syringing and DCG+DE was κ = 0.73 (SE = 0.04, 95% confidence interval [CI]: 0.66-0.80, p < 0.01). When divided into presaccal and postsaccal obstruction categories, the kappa values were κ = 0.40 (SE = 0.11, 95% CI: 0.19-0.62, p < 0.01) and 0.55 (SE = 0.09, 95% CI: 0.37-0.73, p < 0.01), respectively. Furthermore, when limited to common canaliculus obstruction (stenoses), which accounted for 78% (46 LPs) of the total presaccal obstructions, the kappa value was κ = 0.29 (SE = 0.12, 95% CI: 0.05-0.54, p = 0.021), which demonstrated the lowest consistency between syringing and DCG+DE. Conclusion: Syringing was "substantially" in agreement with DCG+DE in detecting the degree of LP obstruction. Moreover, syringing was a sufficiently sensitive and specific test when performed by an experienced clinician. However, distinguishing between complete and partial obstructions by syringing was sometimes difficult, particularly in the common canaliculus obstruction (stenosis).

Functional epiphora: an under-reported entity.

PURPOSE: To determine the etiology of epiphora in a tertiary Australian lacrimal clinic and highlight the high proportion of 'functional' cases. METHODS: Single-center retrospective review: Records of adult patients presenting to a tertiary lacrimal clinic from January 2011 to February 2021 with epiphora were reviewed. Patients underwent testing with syringing/probing and lacrimal imaging to reach a diagnosis of functional epiphora. Functional epiphora was diagnosed based on the exclusion of alternate causes of epiphora on clinical examination, patent lacrimal syringing, normal dacryocystography, and delay on dacryoscintigraphy. RESULTS: Five hundred and seventy-six symptomatic eyes of 372 adult patients (mean 66.2 ± 15.5 years, 63.4% females) with epiphora were evaluated for causes. Post-sac obstruction (stenosis/complete obstruction) and functional epiphora (non-anatomical delay) were the most common causes of presentations to the lacrimal clinic (26% each). Functional epiphora with post-sac delay was substantially more common than functional epiphora with pre-sac delay (89% vs. 11% of functional epiphora cases). In 16% of the cases, no cause for the epiphora was found while more than one cause (multifactorial) was present 11% of the time. CONCLUSION: Functional epiphora was found to be as common as a nasolacrimal anatomical obstruction when lacrimal imaging is utilized.

Evaluation of epiphora by topical contrast-enhanced CT and MR dacryocystography: which one to choose?

BACKGROUND: Our study aims to compare non-invasive imaging such as topical computed tomography dacryocystography (CTD) and topical magnetic resonance dacryocystography (MRD) in patients with epiphora. PURPOSE: To evaluate the practicability of topical contrast media during helical CTD and topical saline during MRD to reveal obstruction in the nasolacrimal drainage system (NLDS). MATERIAL AND METHODS: Twenty participants with nasolacrimal duct obstruction were observed for two years. Ten participants underwent CTD and the other 10 participants underwent MRD. Images were analyzed by two radiologists. Participants were also asked about the level of discomfort of the contrast material versus the saline solution. RESULTS: The NLDS was seen on both CTD and MRD. Very good agreement between the two observers (κ value > 0.81) was seen according to the κ statistics. CTD multiplanar and 3D images allowed for precise diagnosis of the point of obstruction whereas, the MRD did not require any contrast material and showed the point of obstruction. Saline was more comfortable for the patients than topical contrast (P < 0.05). CONCLUSION: Topical CTD and MRD are non-invasive techniques that can visualize the degree and level of obstruction in the NLDS than conventional invasive cannulation dacryocystography. CTD is useful in visualizing the point of obstruction and smaller drainage structures. However, it is a source of ionizing radiation to the lens. The benefit of MRD is that it requires no contrast or radiation; however, it is poor in depicting the bone anatomy and smaller drainage structures. Finally, saline was better tolerated by patients than topical contrast.

Soft stop on syringing and probing may have a high false-positive rate in diagnosing pre-sac obstruction.

PURPOSE: To determine the diagnostic value of 'soft stops' encountered during lacrimal syringing and probing. METHODS: Single-center retrospective review. Adult patients with epiphora attending a tertiary lacrimal clinic from May 2010 to April 2021 were reviewed. Cases with evidence of soft stop encountered during lacrimal syringing/probing were included, and patients with possible canaliculitis or a history of lacrimal surgery were excluded. Findings of syringing/probing consistent with pre-sac obstruction were correlated with dacryocystography (DCG) and surgical findings. RESULTS: 53 (10.2%) canalicular systems had soft stops on syringing/probing and were included in the analysis. The mean age of the patients was 63.8 ± 15.6 (range 28-87) years, and 27 (65.9%) were females. Intraoperative examination findings were available for 27 of 30 cases that underwent lacrimal surgery and DCG was available for 40 systems. Pre-sac obstruction found on syringing/probing was confirmed in 40% and 37% of cases on DCG and surgery, respectively. The correlation between syringing/probing and DCG was stronger for canalicular than for common canalicular location (p = 0.016). Canalicular stenosis on syringing/probing manifested as pre-sac abnormality on DCG in 5/7 (71.4%) compared to 0/6 common canalicular stenosis cases (p = 0.021). Based on the surgical findings, the false-positive rate of a soft stop on syringing/probing was highest for common canalicular 'stenosis' (100%) and lowest for canalicular 'block' (45.5%; p = 0.093). Findings of pre-sac obstructions on DCG were confirmed in 85.7% of the cases intraoperatively (p = 0.035 compared to syringing/probing alone). CONCLUSIONS: Soft stops on probing showed poor correlation with DCG and surgical findings, particularly in common canalicular location.

Non-contrast MR dacryocystography for the evaluation of epiphora and recurrent dacryocystitis: A preliminary study.

INTRODUCTION: Obstruction of the lacrimal drainage represents a common ophthalmologic issue. The blockage may interest any level of the lacrimal drainage pathway, and it is important to find the site of obstruction to plan the most appropriate treatment. In this study, findings from magnetic resonance (MR) dacryocystography were compared with findings from endoscopic and surgical procedures to evaluate the accuracy of MR dacryocystography in localizing the site of nasolacrimal duct obstruction. METHODS: We enrolled twenty-one patients with clinical suspicion of nasolacrimal duct obstruction who underwent dacryoendoscopy and surgery. MR dacryocystography was performed with a heavily T2-weighted fast spin echo sequence in the coronal planes. Before the MRI was performed, a sterile 0.9% NaCl solution was administered into both conjunctival sacs. For each examination, two independent readers (with 8 and 10 years of experience in head and neck imaging) evaluated both heavily 3D space T2-weighted and STIR sequences. RESULTS: Stenosis/obstruction of nasolacrimal duct or lacrimal sac was diagnosed in all 21 patients who underwent MRI dacryocystography. In particular, the site of the obstruction was classified as lacrimal sac in 12 (57%) patients, nasolacrimal duct in 6 (29%) patients, and canaliculi in 3 (14%) patients by both readers. By comparison with the evidence resulting from the endoscopy, there were differences between MRI dacryocystography and dacryoendoscopy in the evaluation of the obstruction's site in three patients, with an overall accuracy of 85.7%. CONCLUSION: MR dacryocystography allows a non-invasive evaluation of the lacrimal drainage pathway, valid for the planning of the most appropriate treatment.

Reference role of middle turbinate axilla in lacrimal sac localization assisted by computed tomographic dacryocystography-reference value of middle turbinate in locating lacrimal sac.

BACKGROUND: The middle turbinate axilla (MTA) has always been used as a stable anatomic landmark for endoscopic surgeons to locate the lacrimal sac on the lateral nasal wall. Yet, little is known about whether the lacrimal sac size will affect the positioning effect of MTA on lacrimal sac. The aim of this study was to investigate the regularity of lacrimal sac size and lacrimal sac localization through the reference position of the MTA on computed tomographic dacryocystography (CT-DCG) images. METHODS: A series of 192 endoscopic dacryocystorhinostomy (DCR) surgeries were performed. All the patients had been diagnosed as unilateral nasolacrimal duct obstruction and received CT-DCG examinations. According to the maximum transverse diameter of the lacrimal sac on CT-DCG, the patients were classified into three groups. Measurements were taken on CT-DCG parasagittal images. RESULTS: The average distance from the sac superior fundus (SSF) to the MTA was 7.52 mm ± 3.23 mm, and it increased with the increase of the maximum transverse diameter of the sac among groups (p < 0.01). The average distance from the common canaliculus (CC) to the MTA was 3.95 mm ± 2.49 mm. No significant difference was observed among the groups (p = 0.11). The average distance from the CC to the SSF was 3.41 mm ± 1.31 mm, and it increased with the increase of the sac transverse diameter among groups (p < 0.01). CONCLUSIONS: The lacrimal sac can be accurately located on the lateral nasal wall by the reference position of the MTA on CT-DCG images. The distance of the SSF to the MTA and the SSF to the CC is related to the lacrimal sac size. The relative position of the CC to the MTA is relatively stable on CT-DCG images, which make it possible to locate the lacrimal sac of different sizes and the corresponding nasal mucosa incision design in endoscopic DCR.

Rhinological Status of Patients with Nasolacrimal Duct Obstruction

Abstract Introduction Studying the state of the nasal cavity and its sinuses and the morphometric parameters of the inferior nasal conchae, as well as a comparative analysis of obtained values in patients with primary (PANDO) and secondary acquired nasolacrimal duct obstruction (SALDO), is relevant. Objective To study the rhinological status of patients with PANDO) and SALDO). Methods The present study was based on the results of computed tomography (CT) dacryocystography in patients with PANDO (n =45) and SALDO due to exposure to radioactive iodine (n = 14). The control group included CT images of paranasal sinuses in patients with no pathology (n =49). Rhinological status according to the Newman and Lund-Mackay scales and volume of the inferior nasal conchae were assessed. Statistical processing included nonparametric statistics methods; χ2 Pearson test; and the Spearman rank correlation method. Results The difference in values of the Newman and Lund-Mackay scales for the tested groups was significant. A significant difference in scores by the Newman scale was revealed when comparing the results of patients with SALDO and PANDO. Comparing the scores by the Lund-Mackay scale, a significant difference was found between the results of patients with SALDO and PANDO and between the results of patients with PANDO and the control group. Conclusion It was demonstrated that the rhinological status of patients with PANDO was worse than that of patients with SALDO and of subjects in the control group. No connection was found between the volume of the inferior nasal conchae and the development of lacrimal duct obstruction.

Rhinological Status of Patients with Nasolacrimal Duct Obstruction.

Introduction Studying the state of the nasal cavity and its sinuses and the morphometric parameters of the inferior nasal conchae, as well as a comparative analysis of obtained values in patients with primary (PANDO) and secondary acquired nasolacrimal duct obstruction (SALDO), is relevant. Objective To study the rhinological status of patients with PANDO) and SALDO). Methods The present study was based on the results of computed tomography (CT) dacryocystography in patients with PANDO ( n = 45) and SALDO due to exposure to radioactive iodine ( n = 14). The control group included CT images of paranasal sinuses in patients with no pathology ( n = 49). Rhinological status according to the Newman and Lund-Mackay scales and volume of the inferior nasal conchae were assessed. Statistical processing included nonparametric statistics methods; χ 2 Pearson test; and the Spearman rank correlation method. Results The difference in values of the Newman and Lund-Mackay scales for the tested groups was significant. A significant difference in scores by the Newman scale was revealed when comparing the results of patients with SALDO and PANDO. Comparing the scores by the Lund-Mackay scale, a significant difference was found between the results of patients with SALDO and PANDO and between the results of patients with PANDO and the control group. Conclusion It was demonstrated that the rhinological status of patients with PANDO was worse than that of patients with SALDO and of subjects in the control group. No connection was found between the volume of the inferior nasal conchae and the development of lacrimal duct obstruction.

Analysis of Lacrimal Duct Morphology from Cone-Beam Computed Tomography Dacryocystography in a Japanese Population.

Purpose: The dacryoendoscope is a practical instrument for the examination and the treatment of lacrimal duct obstruction. Nevertheless, as it is a rigid fiberscope, manipulation of the endoscope is somewhat affected by the patient's lacrimal duct alignment and the skeletal structure of the face. The morphology and inclination of the lacrimal duct vary among individuals and ethnic groups. We aimed to evaluate the alignment of the lacrimal duct from the perspective of endoscopic maneuverability in a Japanese population. Methods: This retrospective study analyzed the cone-beam computed tomography dacryocystography (CBCT-DCG) images of 102 patients diagnosed with unilateral primary acquired nasolacrimal duct obstruction (PANDO) at Ehime University Hospital from December 2015 to May 2021. The following parameters of the lacrimal duct on the contralateral side of unilateral PANDO were investigated: (1) angle formed by the superior orbital rim-internal common punctum-nasolacrimal duct opening, (2) angle formed by the lacrimal sac and the nasolacrimal duct, (3) length of the lacrimal sac, and (4) length of the nasolacrimal duct. Results: Measurements of the above parameters were (1) 10.2° ± 7.8° (range, -11° to +27°), (2) -6.3° ± 14.1° (range, -43° to +40°), (3) 8.9 ± 2.3 mm (range, 4.3-17.1), and (4) 13.2 ± 2.7 mm (range, 5.7-20.7), respectively. The Shapiro-Wilk test demonstrated that the values of all parameters, except (3), followed a normal distribution (p = 0.55, 0.30, 0.0002, and 0.39, respectively). No significant difference was found between the female and male groups (p > 0.05). Conclusion: This study reported anthropometric analysis data of the morphology of the lacrimal ducts using CBCT-DCG in a Japanese population. In our cohort, the line from the superior orbital rim through the internal common punctum to the nasolacrimal duct opening inclined anteriorly in 92% of the patients.

Syringing has limited reliability in differentiating nasolacrimal duct stenosis from functional delay.

PURPOSE: To elucidate the role of syringing in assessing nasolacrimal duct (NLD) stenosis and non-anatomical functional NLD delay. METHODS: Consecutive adult patients with epiphora attending a tertiary lacrimal clinic from June 2011 to March 2021 were reviewed. Cases with evidence of canalicular stenosis or other identifiable causes of epiphora were excluded. Following syringing, patients were investigated with dacryocystography (DCG) and dacryoscintigraphy (DSG). The sensitivity and specificity of syringing were evaluated using the combined findings on DCG and DSG. RESULTS: A total of 289 symptomatic lacrimal systems (197 patients; mean age 65.5 ± 14.9 years, 66% females) were included. More than one-third of cases with both normal DCG and DSG were noted to have some degree of reflux on syringing (specificity = 65.1%, 95% CI 50.2-77.6%). The sensitivities were considerably low for NLD stenosis (i.e., stenosis on DCG and delay on DSG) and for functional NLD delay (i.e., normal DCG and delay on DSG), of which 43.7% (95% CI 32.2-55.9%) and 54.3% (95% CI 45.7-62.7%) had full patency on syringing, respectively (p = 0.17). CONCLUSIONS: Full patency on syringing was unreliable for ruling out NLD stenosis and functional delay. Furthermore, a positive syringing may be associated with functional NLD delay and cannot reliably differentiate it from stenosis.

Lacrimal imaging findings in fellow asymptomatic eyes of unilateral epiphora.

AIMS: To investigate the prevalence of subclinical anatomical and functional abnormalities of lacrimal drainage in fellow asymptomatic eyes of unilateral epiphora using dacryocystography and dacryoscintigraphy. METHODS: Retrospective case note review of lacrimal imaging of adult patients presenting to a hospital Oculoplastic clinic with unilateral epiphora over 10 years. RESULTS: A total of 172 patients with unilateral epiphora were included. The median age was 67 (range 18-96 years). A dacryoscintigraphy (DSG) abnormality was present in 54 (42%) asymptomatic eyes, and dacryocystography (DCG) abnormality in 10 (10%). The most common finding on DSG was no delay in 76 eyes (58%), and most common DSG abnormality was post sac delay in 51 (39%) eyes. The most common finding on DCG was no obstruction in 88 (90%) eyes, and the most common DCG abnormality was post sac stenosis (7.1%). Of the 92 asymptomatic eyes with both DCG and DSG, 53 (57%) showed neither an obstruction on DCG or delay on DSG, and 28 (30%) showed a post sac delay on DSG and no abnormality on DCG. CONCLUSION: Greater than a third of asymptomatic eyes displayed post sac delay on DSG, frequently without accompanying anatomical obstruction on DCG. Subclinical DSG delay in asymptomatic eyes may represent physiological variation in tear transit time, subclinical lacrimal drainage dysfunction or anatomical stenosis undetected by DCG. Furthermore, the DSG results of fellow asymptomatic eyes in unilateral epiphora may not represent a normal standard that can be utilised for comparison. Further investigation with dacroyendoscopy, the use of control eyes, and long term follow up is required.

Anatomy of the nasolacrimal duct in Persian cats determined by computed tomographic dacryocystography.

OBJECTIVE: This study sought to describe the anatomical characteristics of the nasolacrimal duct of Persian cats as observed by computed tomographic dacryocystography. ANIMAL STUDIED: Ten cats weighing 3-6 kg (three live cats and seven cadaveric specimens). PROCEDURES: The animals were submitted to bilateral computed tomographic dacryocystography, totaling 20 nasolacrimal ducts. Dorsal, sagittal, and transverse planes were studied. Two additional skulls were also dissected following latex injection into the nasolacrimal duct. The length and width of the nasolacrimal duct and lacrimal canaliculi, and the distance between the nasolacrimal duct and the root of the upper canine tooth at the point of closest proximity were measured. RESULTS: The nasolacrimal duct followed a convoluted course, particularly in the middle and rostral portions. Duct stenosis (width reduction equal to or >75%) and dilations (width increase equal to or >50%) were also detected, particularly in the rostral portion. Nasolacrimal duct length and width ranged from 1.3 to 1.5 cm and 1.5 to 2.3 mm, respectively. Mean lacrimal canaliculus length and width corresponded to 3.1 mm and 0.4 mm, respectively. Mean distance from the nasolacrimal duct to the canine tooth was 2.4 mm. The root of this tooth interfered with the course of the nasolacrimal duct. CONCLUSION: This study provided anatomical information for clinical assessment of the nasolacrimal drainage system in Persian cats.

Degree of agreement between dacryoscintigraphy and dacryocystography examinations results in primary acquired nasolacrimal duct obstruction.

BACKGROUND: This diagnostic study aimed to assess degree of agreement between dacryoscintigraphy and dacryocystography as supporting examinations in patients with primary acquired nasolacrimal duct obstruction (PANDO). Patients with PANDO who complained of epiphora and visited our outpatient clinic were subsequently sent for dacryoscintigraphy and dacryocystography examinations. Side effects and convenience of both examinations were assessed by observation and questionnaire. MATERIAL AND METHODS: Through irrigation and probing, there were 47 out of 62 eyes were found with PANDO. As much as 87.1% subjects were female, with mostly (74.2%) aged > 40 years old. With dacryoscintigraphy, time needed to reach sac was 0 minutes, 5 minutes (duct), and 12.5 minutes (nasal cavity). RESULTS: Degree of agreement between both examinations was 83.8% to determine obstruction and 70.9% to locate obstruction. There were 22 subjects complained about pain in dacryocystography examination while none with dacryoscintigraphy (p < 0.005). Sixteen subjects feel dacryoscintigraphy examination was more convenient, eleven subjects feel dacryocystohraphy was more convenient, while 4 subjects feel the two examinations were similar. CONCLUSIONS: Even though dacryocystography examination was considered more painful than dacryoscintigraphy, both examinations had high convenience level for patients. Dacryoscintigraphy and dacryocystography also had a good agreement in detecting and locating obstruction in PANDO.