A new method of evaluating lacrimal drainage

Evaluation of Asymptomatic Fellow Eyes of Patients with Unilateral Epiphora by Lacrimal Irrigation Test and Dacryoscintigraphy

OBJECTIVE

To evaluate the findings of dacryoscintigraphy (DSG) and lacrimal irrigation test (LIT) in asymptomatic fellow eyes of patients with unilateral epiphora, as well as the relationship between pathology of the lacrimal drainage system in symptomatic and asymptomatic eyes.

METHODS

This study included 396 patients who were followed up for symptomatic unilateral epiphora due to nasolacrimal stenosis or obstruction between January 2022 and June 2024. Initially, LIT was performed in both eyes of all patients (both symptomatic and asymptomatic eyes) using a 2 ml lacrimal cannula. In all cases, DSG was performed as part of the routine examination.

RESULTS

Among symptomatic eyes with unilateral epiphora, 72.2% (n = 286) had nasolacrimal duct obstruction, while 27.8% (n = 110) had nasolacrimal duct stenosis. When the asymptomatic fellow eyes of 396 eyes with unilateral epiphora were examined, DSG was normal in 247 eyes (62.4%) and abnormal in 149 eyes (37.6%). DSG abnormalities were post-sac delay in 137 eyes (34.6%) and pre-sac delay in 12 eyes (3.0%). When asymptomatic fellow eyes were analysed with LIT, 326 eyes (82.3%) had normal LIT, while only 70 eyes (17.7%) had an obstruction in LIT. Among the asymptomatic eyes, 239 (60.4%) had neither delay in DSG nor obstruction in LIT, while 87 (22.0%) had delay in DSG without obstruction in LIT. Only 8 (3.2%) of 247 eyes with no delay in the DSG had a blockage in the LIT. The concordance rate between LIT and DSG was 76.0% (301 eyes).

CONCLUSION

The combined use of DSG and LIT in the evaluation of asymptomatic eyes of cases with unilateral epiphora is crucial to improve diagnostic accuracy and develop a more targeted treatment approach.

Evaluation of anatomical and functional success in canalicular laceration repair using anterior segment optical coherence tomography and dacryoscintigraphy

PURPOSE

To assess the anatomical and functional outcomes in patients who underwent surgery for canalicular laceration and did not experience significant epiphora, and to compare these outcomes with contralateral uninjured eye.

METHOD

Dacryoscintigraphy, anterior segment optical coherence tomography (OCT), MUNK scores, and a satisfaction questionnaire were administered to 24 patients who had canalicular laceration repair without significant epiphora and had a minimum of 6 months of follow-up. Tear meniscus height (TMH), depth (TMD), and area (TMA) were measured using anterior segment OCT and compared with the values in the uninjured eye.

RESULTS

Sixteen patients (67 %) had lower, 7 (29 %) had upper canaliculus, and one (4 %) had lacerations in both canaliculi. Five patients (20.83 %) had concomitant orbital fractures, and three patients (12.5 %) underwent additional repair for corneoscleral laceration. Bicanalicular silicone tube intubation was performed in one patient, while Mini-Monoka stent intubation was used for all other patients. The mean follow-up period was 41 ± 22.3 months, and the mean interval between trauma and surgery was 30.2 ± 29 h. The mean duration until tube removal was 3 ± 2.54 months. The MUNK score was 1 in eight patients (33 %) and 0 in sixteen patients (67 %). Canalicular lacerations occurred due to home accidents in 8 patients, work accidents in 4, assaults in 5, and traffic accidents in 7. Dacryoscintigraphy showed drainage of tracer into the nasal cavity in dynamic imaging for 12 patients. Five patients had retention in the sac, four had prolonged and reduced drainage, one had reduced drainage, and two showed no drainage in the first and second hour images. In the operated eye, the mean tear meniscus height (TMH) was 279.6 µm, depth (TMD) was 215 µm, and area (TMA) was 28.9 µm². In the healthy eye, the mean TMH was 221.5 µm, TMD was 152.5 µm, and TMA was 15.3 µm². The anterior segment OCT values for the affected eye were statistically significantly higher than those for the healthy eye (p = 0.044 for TMH, p = 0.003 for TMD, p = 0.006 for TMA). TMD and TMA were statistically significantly higher in patients with a MUNK score of 1 (p = 0.019 for TMD, p = 0.05 for TMA). Abnormal dacryoscintigraphy results were more common in patients with globe injuries requiring additional surgery.

CONCLUSION

Although patients did not report epiphora after canalicular laceration repair, our observations indicated potential functional and anatomical differences in dacryoscintigraphy and anterior segment OCT compared to their healthy eyes. We believe that close follow-up is crucial to identify and address any issues that may arise in the future following surgery.

Incompatibility of Lacrimal Syringing Test with Dacryoscintigraphy in Patients Undergoing Successful Dacryocystorhinostomy Surgery

Purpose  The aim of our study was to evaluate the compatibility of lacrimal syringe test with dacryoscintigraphy (DSG) in the postoperative evaluation of external dacryocystorhinostomy (Ext-DCR) surgery. Material and Methods  Thirty eyes of 30 patients suffering from unilateral epiphora with discharge and showing complete obstruction on lacrimal irrigation test were included in the study. Patients with dysfunctional lacrimal pump function, revision surgery, partial obstruction, and ocular surface diseases were not included in the study. Verification of the nasolacrimal duct obstruction (NLDO) was achieved with dye disappearance test, Jones test 1 (JT 1), and JT 2. According to the type of obstruction seen on DSG, patients were classified into two groups: presac and postsac obstruction. Patients with complete obstruction detected in the lacrimal syringing and dynamic scintigraphy underwent Ext-DCR, and the results were evaluated. Results  Thirty patients, mean age 58.93 ± 12.11 years, all with unilateral NLDO were included in the study. All had grade 5 Munk score epiphora and discharge. The mean duration of obstruction was 24.57 ± 10.65 months. In the lacrimal irrigation test, all patients had complete obstruction in one eye, while the other eye was normal. According to preoperative DSG results, there were 20 (66.7%) patients with presac delay and 10 (33.3%) patients with postsac delay. All patients underwent Ext-DCR with silicone tube intubation and were followed for 1 year. Although there was symptomatic improvement in all patients and the lacrimal syringing test was patent, no change was seen in scintigraphy. Conclusion  Although DSG is a sensitive nuclear medicine method, it is not useful for predicting the functional success of the Ext-DSR.

Normative Quantitative Values for Dacryoscintigraphy and the Effect of Lid Massage

Our objectives were to establish normative quantitative values for dacryoscintigraphy in an older population and to evaluate the effect of lid massage. Methods: We conducted a prospective study of 44 eyes of 22 participants aged between 54-90 y that had no symptoms of epiphora and no clinical tear film instability, lid abnormality, lacrimal system impairment, or patent lacrimal duct on syringing. Dacryoscintigraphy was performed and interpreted by a single nuclear medicine physician. The scan protocol involved instillation of ^99mTc-pertechnetate in each eye, with a 45-min scan performed with 1-min frames. Lid massage and a sinus clearing maneuver were then performed, followed by a further 45 min of scanning. Results: The mean age of the 22 participants was 71.9 y. Quantitative analysis by half-clearance time (HCT) demonstrated a median presac HCT of 25.5 ± 15.0 min and a whole-eye HCT of 40.0 ± 19.5 min. There was no association between age or sex and HCT. Qualitatively, 29 of 44 eyes (66%) appeared to have at least 1 region of delayed clearance, with improvement noted in 23 after lid massage (79%). Conclusion: We report the quantitative values for dacryoscintigraphy in an asymptomatic older population who had normal findings on lacrimal examination. A high rate of delay in radiotracer transit on qualitative examination suggesting a low specificity. The false-positive rate was significantly improved with the novel approach of adding lid massage, and the significance of this finding merits further research.

Clinical Efficacy of Lacrimal Syringing under General Anesthesia

Purpose: To compare the results of lacrimal syringing performed in clinical practice and under general anesthesia, and the clinical efficacy of lacrimal syringing under general anesthesia before endoscopic dacryocystorhinostomy and dacryoscintigraphy.Methods: The study included 148 eyes of 82 patients who underwent endoscopic dacryocystorhinostomy and silicone tube intubation from August 2018 to April 2019. The patients were examined with lacrimal syringing in clinical practice and re‐examined under general anesthesia. Based on the change in lacrimal syringing, the patients were assigned to inconsistent and consistent groups. The inconsistent group was subclassified into complete (‘regurgitation’ of lacrimal syringing changes to a ‘passage’ pattern) and partial improvement groups (the degree of regurgitation improves under general anesthesia).Results: Twenty (13.5%) eyes showed inconsistent results of lacrimal syringing performed in clinical practice and under general anesthesia; all showed improved passage under general anesthesia. The surgical results did not differ significantly (p = 0.336) between the consistent and inconsistent groups, but did between the complete and partial improvement groups (p < 0.01). Conclusions: Lacrimal syringing under general anesthesia may enable an accurate preoperative diagnosis of the degree of obstruction. The combined results of dacryoscintigraphy and lacrimal syringing performed in clinical practice and under general anesthesia allow surgeons to evaluate the lacrimal drainage anatomy precisely and may be useful for predicting the functional success of endoscopic dacryocystorhinostomy.

Possibility of Pseudo-Obstruction in Lacrimal Canalicular Obstruction Diagnosed with Dacryocystography

INTRODUCTION

Endoscopic dacryocystorhinostomy (DCR) is the treatment of choice for patients with lacrimal drainage system obstruction. Dacryocystography (DCG) is one of the most common preoperative studies and considered as a useful test demonstrating the anatomy of lacrimal drainage systems.

OBJECTIVE

This study was designed to evaluate the diagnostic efficacy of DCG for canalicular obstruction and to compare surgical outcomes between true-obstruction versus pseudo-obstruction diagnosed with DCG.

METHODS

A retrospective study was performed on 45 consecutive patients with lacrimal canalicular obstruction who had underwent endoscopic DCR with silicone tube insertion from January 2009 to December 2014 at a single tertiary hospital. A review of medical records included demographic data, preoperative symptoms and signs, results of intraoperative canalicular probing, and surgical outcomes including the postoperative symptom improvement and endoscopic finding.

RESULTS

Of 45 patients, 34 patients (75.6%) had true-canalicular obstructions and 11 patients (24.4%) had pseudo-canalicular obstructions. The success rate of endoscopic DCR was 50% (17 of 34) in cases with true-canalicular obstruction while 90.9% (10 of 11) in pseudo-canalicular obstruction (p value <0.05). No intraoperative or postoperative complications including sinusitis or synechia were found.

CONCLUSIONS

About a quarter of lacrimal canalicular obstruction cases diagnosed with DCG seem to be pseudo-obstruction. The success rate of endoscopic DCR in pseudo-canalicular obstruction is similar to that of saccal and nasolacrimal ductal obstruction.

Neuroimaging of Adult Lacrimal Drainage System

The lacrimal drainage system (LDS) pathology is frequently encountered in the ophthalmology setting but is rarely discussed in the radiology literature. This is even truer for adult LDS lesions despite increase utilization of computed tomography and magnetic resonance in imaging for diagnosis of LDS pathology. The purpose of this image rich review is to highlight common adult LDS pathologies and introduce the radiologist to rare disease entities affecting this pathology rich anatomical region with emphasis on imaging findings, clinical presentation, and differential generation.

Canaliculorhinostomy as a treatment for nasolacrimal duct obstruction in dogs and cats

OBJECTIVES

To create a replacement nasolacrimal system, using the puncta and canaliculi, with prolonged implant retention and minimal use of Elizabethan collars or other restraint devices.

MATERIALS AND METHODS

The method was used in 11 dogs and two cats. Silicone tubing was placed through both canaliculi and, via a drill hole, into the nasal cavity. Distally, the tubing ends were tied in a subcutaneous pocket lateral to the premaxilla. Tubing retention time was 4 to 7 months. Elizabethan collars were used only until skin suture removal at 2 weeks.

RESULTS

In all animals, a functional nasolacrimal system was re-created and remained patent over prolonged follow-up periods. Adverse effects and complications were mild.

CLINICAL SIGNIFICANCE

The described method is relatively straightforward, thereby making relief of tear outflow problems widely accessible.

Evaluation of Patients for Endoscopic DCR: Sac Syringing and Radionuclide Scintigraphy

To evaluate the importance of sac syringing and radionuclide scintigraphy for pre operative work up of patients with epiphora. In this study, from the year Jan. 2013 to Jan. 2016, patients of epiphora were subjected to radionuclide scintigraphy of lacrimal apparatus in addition to sac syringing and probing. The significance of adding radionuclide scintigraphy in pre op assessment of epiphora was statistically assessed. 146 lacrimal systems were enrolled in the study. Out of them, 89 were males and 57 were females. The mean age of the patients was 42 years. Of the 146 lacrimal systems evaluated, scintigraphy detected 25 cases of common canalicular block versus 8 cases by sac syringing. Also radionuclide scintigraphy was able to detect 11 cases of functional obstruction which were patent on syringing. Results were analysed statistically. Correct diagnosis of site of obstruction is essential to predict a better surgical outcome of endoscopic DCR as it is a highly successful surgical procedure which can be done in distal NLDO only. We recommend that all patients of epiphora should undergo sac syringing as an initial test. This is a simple, inexpensive procedure which can be done as an OPD procedure in a short time. However, radionuclide scintigraphy can be added as an additional investigation to more accurately delineate site of block. It is an objective test and delineates the lacrimal system both anatomically and functionally. Also it diagnoses functional block which appears patent on syringing.

Clinical utility of SPECT/CT and CT-dacryocystography-enhanced dacryoscintigraphy in the imaging of lacrimal drainage system obstruction

Purpose

Epiphora is commonly caused by a relative or complete occlusion in the lacrimal drainage system (LDS), principally a nasolacrimal duct obstruction (NLDO). Dacryoscintigraphy (DSG), an extensively assessed imaging technique in diagnosing its abnormalities, can provide only planar images, according to which it needs to be improved. Our aim was to evaluate clinical utility of simultaneous DSG and single-photon emission computed tomography/computed tomography (SPECT/CT) combined with computed tomographic dacryocystography (CT-DCG) in the evaluation of LDS.

Methods

Dynamic imaging with DSG was performed, and tracer radioactivity was detected by a gamma camera. Successively, SPECT/CT images of the involved region were gained, followed by CT-DCG, during which a contrast medium was syringed into the affected LDS, and finally contrast CT scans were obtained again from the same region.

Results

Fifty-seven patients, mean age 54.25 (± 18.26) years all with unilateral NLDO and 32 control subjects, all with patent LDS, mean age 49.88 (± 18.61) years were evaluated in the study. Delayed outflow of tearing eyes was exposed to DSG compared to the fellow and control eyes. The highest value for sensitivity was observed for SPECT/CT, followed by CT-DCG and DSG techniques, while combining DSG with SPECT/CT, DSG with CT-DCG, and SPECT/CT with CT-DCG, the sensitivity increased to 96.49%, 92.98%, and 94.73%, respectively.

Conclusions

Although DSG is a sensitive nuclear medicine method, it only provides useful clinical data when simultaneously supplemented with SPECT/CT and CT-DCG trials as they jointly can offer valuable information about the localization of an abnormality and verify stenosis or obstruction.

Evaluation of the tear clearance rate by dacryoscintigraphy in patients with obstructive meibomian gland dysfunction

PURPOSE

To measure tear clearance values in patients with meibomian gland dysfunction (MGD) with a dynamic nuclear medicine method, namely, dacryoscintigraphy (DSCI).

METHODS

Twenty-four MGD patients and 24 healthy volunteers were examined. During DSCI one drop of a solution with 100 MBq/mL^99mTc sodium pertechnetate was instilled with a micropipette into the lacrimal lake of both eyes. Measurements were performed according to a dynamic data acquisition protocol, which resulted in summed DSCI images. Data were also evaluated separately in special regions of interest (ROI), and consecutive time activity curves were created. Tear clearance (T½) values were calculated based on the activity curves. In addition, tear osmolarity measurements, tear breakup time (tBUT), and Schirmer I (ST_I) tests were performed prior to DSCI examination.

RESULTS

The T½ values were 29.91 ± 11.61 min in MGD patients and 6.26 ± 1.5 min in healthy controls. Tear osmolarity parameters were 308 ± 9.41 mOsm/L and 288.9 ± 6.4 mOsm/L, tBUT values were 5.54 ± 2.73 s and 11.4 ± 2.7 s, while the ST_I test values were 6.17 ± 2.78 mm and 13.58 ± 3.8 mm, respectively. The differences were significant (p < 0.01) in all cases.

CONCLUSIONS

Although the MGD patients' lacrimal drainage systems were patent their tear clearance values were significantly higher than those of healthy volunteers, which may be caused by decreased drainage of tears from the eyes towards the nasal cavity. The understanding of new features regarding the altered physico-chemical characteristics of MGD tears has been augmented by the results of this study.

Ocular Biodistribution Studies using Molecular Imaging

Classical methodologies used in ocular pharmacokinetics studies have difficulties to obtain information about topical and intraocular distribution and clearance of drugs and formulations. This is associated with multiple factors related to ophthalmic physiology, as well as the complexity and invasiveness intrinsic to the sampling. Molecular imaging is a new diagnostic discipline for in vivo imaging, which is emerging and spreading rapidly. Recent developments in molecular imaging techniques, such as positron emission tomography (PET), single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI), allow obtaining reliable pharmacokinetic data, which can be translated into improving the permanence of the ophthalmic drugs in its action site, leading to dosage optimisation. They can be used to study either topical or intraocular administration. With these techniques it is possible to obtain real-time visualisation, localisation, characterisation and quantification of the compounds after their administration, all in a reliable, safe and non-invasive way. None of these novel techniques presents simultaneously high sensitivity and specificity, but it is possible to study biological procedures with the information provided when the techniques are combined. With the results obtained, it is possible to assume that molecular imaging techniques are postulated as a resource with great potential for the research and development of new drugs and ophthalmic delivery systems.

How reliable is the lacrimal scintigraphy report? An inter-observer agreement and reliability study

AIM

To assess the inter-observer agreement and reliability as well as intra-observer repeatability for lacrimal scintigraphy (LS) reports with and without considering the irrigation test results.

METHODS

A prospective, observational, cross sectional study. Two masked clinicians (lacrimal surgeon and nuclear medicine specialist) independently reported 100 LS images (50 patients of >6 years of age with unilateral anophthalmic socket) in a university hospital. The lacrimal surgeon performed a diagnostic irrigation test and repeated the report of the same LS images 2y after the first report (intra-observer agreement). A weighted Kappa analysis was performed to determine inter-observer agreement and reliability as well as intra-observer repeatability for the type (normal, partial and complete obstruction) and location (presac, preduct, and intraduct) of the obstruction. Subgroup analysis was also performed with consideration of irrigation test results.

RESULTS

A significantly moderate agreement was found between lacrimal surgeon and nuclear medicine specialist for both the type (Kappa=0.55) and location (Kappa=0.48) of obstruction. Agreement values were higher for the type (Kappa=0.61 vs 0.41) and location (Kappa=0.56 vs 0.31) of obstruction in cases with normal than abnormal irrigation test. Strong and significant intra-observer (lacrimal surgeon) repeatability was found for both the type (Kappa=0.66) and location (Kappa=0.69) of obstruction. LS showed no to slight reliability based on irrigation test.

CONCLUSION

A moderate agreement is found between lacrimal surgeon and nuclear medicine specialist regarding the interpretation of LS suggesting the importance of consensus groups among nuclear medicine specialists and lacrimal surgeons to create a common language for interpretation of LS. Intra-observer repeatability is strong for the lacrimal surgeon.

Dacroscintigraphy by Pediatric Dropper Technique: A User-friendly Instillation Procedure of Radiotracer

Context:

Instillation or application of the radiotracer over the tear film is one of the important parts of dacroscintigraphy. Our study explains the value of an improvised dropper technique so that desired amount of radioactivity in desired volume can be instilled over the tear film.

Aim:

The aim of the study is to introduce a simple and convenient instillation method based on dropper technique for performing dacroscintigraphy. This improvised dropper technique can be used so that desired amount of radioactivity in desired volume can be instilled over the tear film. The objectives of this experiment are to measure the volume and activity of each drop from the dropper.

Settings and Design:

Experiment of volume and activity measurement standardization was carried out in two parts. In the first part, we calculated the volume of each drop indirectly to standardize the volume of drop. In the second part, we standardized the activity in each drop by measuring it in a dose calibrator.

Subjects and Methods:

In this study, we used a common pediatric dropper of approximately 1 ml capacity, radioactivity (^99mTcO4 pertechnetate), sample vial (container), vial holder, a pair of nonsterile gloves, dose calibrator, etc., Experiments of volume and radioactivity standardization were carried out in two parts. The first part of experiment calculated volume of each drop indirectly, and in the second, we standardized the activity in each drop by measuring it in dose calibrator. Statistical analysis used: Analysis of variance test was used to calculate the correlation of readings by same individual as well as among the three individuals

Results:

After analysis of result obtained, it was understood that there was no significant difference found in volume and activity of each drop in the readings recorded by same individual as well as among the three individuals. The calculated activity and observed activity were 86.64 and 79.16 μCi, respectively. The difference was only 8.63% lying within acceptable limits.

The value of lacrimal scintillography in the assessment of patients with epiphora

PurposeTo assess the influence of dacryoscintillography (DSG) on the treatment decision for patients with epiphora and clinically patent non-functioning lacrimal systems.MethodsA retrospective 3-year review. Inclusion: patients having DSG for epiphora with delayed tear clearance, lacrimal system patency on syringing, and no visible external cause for watering. On the basis of regurgitation during syringing, tear ducts were divided into freely patent (FP≤20%) or stenosed. The DSG results were examined for correlation with symptoms and clinical examination, the influence on decision to proceed to dacryocystorhinostomy (DCR), and the ability to predict the surgical outcome.ResultsA total of 242 eyes were examined. The clinical diagnosis was FP in 45.5%, nasolacrimal duct stenosis (NLDS) in 26.4%, and other in 3.3%. The DSG was normal in 30.9% of FP and 18.7% of NLDS eyes. Of the asymptomatic eyes, 46.7% had an abnormal DSG. DSG sensitivity was 73.6% and specificity 53.3%. There was no significant difference in DSG results in those with FP or NLDS.DCR was recommended in 39.1% of the symptomatic eyes with abnormal DSG. DCR surgery was considered inappropriate in all 46 eyes with normal DSG. DCR was successful in 76.5%, however, the DSG result did not affect the success of surgery.ConclusionDSG has severe limitations due to lack of correlation with symptoms and clinical examination, inability to separate lacrimal duct narrowing from lacrimal pump function, and inability to predict the results of surgery. DSG can at best provide limited guidance on whether to proceed to DCR surgery.

External Dacryocystorhinostomy for the Treatment of Functional Nasolacrimal Drainage Obstruction

OBJECTIVES

To determine the outcome and long-term efficacy of external dacryocystorhinostomy (ext-DCR) with or without bicanalicular silicon intubation in patients with functional nasolacrimal drainage obstruction (FNLDO).

MATERIALS AND METHODS

Patients with epiphora and patent lacrimal systems on nasolacrimal irrigation were prospectively enrolled in the study. Each patient was assessed with lacrimal scintigraphy to differentiate drainage abnormalities as presac (proximal) or postsac (distal) delays. All patients underwent ext-DCR; bicanalicular silicone intubation was performed only in presac delay cases. On follow-up examinations patients were asked to report their symptoms as none, mild, moderate or unchanged. Success was defined as lacrimal patency to irrigation and no or mild epiphora at the end of the follow-up period.

RESULTS

Twenty-six lacrimal systems of 23 patients were eligible for inclusion. There were 9 presac delay and 17 postsac delay cases. Average follow-up time was 72.85 weeks (47-88 weeks). A successful outcome was achieved in 76.9% of the operated lacrimal systems. Success rate was 55.5% among presac obstructions and 88.2% among postsac obstructions.

CONCLUSION

The long-term efficacy of ext-DCR in FNLDO patients is confirmed with our overall successful outcome of 76.9%. In preoperative assessment, lacrimal scintigraphy is helpful to determine the surgical approach and to predict the surgical outcome.

Endoscopic dacryocystorhinostomy as treatment for lower lacrimal pathway obstructions in adults: Review article

Obstruction of the lacrimal pathway is manifested by epiphora, infection, and blurred vision as well as ocular and facial pain. Conservative treatments only achieve temporary relief of symptoms, thus surgery is the treatment of choice. Dacryocystorhinostomy (DCR) is recognized as the most suitable treatment for patients with obstructions of the lacrimal system at the level of the sac or in the nasolacrimal duct. The aim of this operation is to create a bypass between the lacrimal sac and the nasal cavity. During the past 2 decades, advances in rigid endoscopic equipment and other instruments have made it possible to obtain more information about the anatomic landmarks of the nasolacrimal system, which led to the development of less-invasive and safer endoscopic techniques. However, many parts of the treatment process related to endoscopic endonasal dacryocystorhinostomy (EN-DCR) still remain controversial. This article reviews the published literature about the technical issues associated with the success of EN-DCR, and clarifies the pros and cons of different pre- and postoperative procedures in adults with lower lacrimal pathway obstructions.

Dacryoscintigraphic findings in the children with tearing

Purpose

To investigate the diagnostic effectiveness of dacryoscintigraphy in children with tearing; to evaluate tear clearance rate as a diagnostic factor of dacryoscintigraphy in children with tearing; and to analyze the results of treatment according to dacryoscintigraphic findings in children with tearing.

Methods

Between January 2010 and April 2014, 176 eyes of 88 children with tearing (49 boys and 39 girls; mean age, 23.81 ±14.67 months; range, 12 to 72 months) were studied retrospectively. Of these, 37 of 88 children with tearing were bilateral cases, and 51 were unilateral cases. None of the patients had a history of craniofacial disorder or trauma. The chief complaint of tearing with or without eye discharge and delivery mode, past history of neonatal conjunctivitis, syringing, or probing were collected from parents, grandparents, or previous hospital data. The drainage pattern of the nasolacrimal duct was analyzed, and the clearance rate of 50 µCi 99m technetium pertechnetate was measured by dacryoscintigraphy.

Results

According to the dacryoscintigraphy results, 98 of 125 eyes (78.4%) with tearing showed nasolacrimal obstruction and 29 of 51 eyes (56.9%) without tearing showed patency. There was a significant difference between tearing eyes and normal eyes (p = 0.001). The clearance rate difference after 3 and 30 minutes was 16.41 ± 15.37% in tearing eyes and 23.57 ±14.15% in normal eyes. There was a significant difference between epiphoric eyes and normal eyes (p = 0.05). Based on the dacryoscintigraphic findings, nasolacrimal-duct obstruction was treated with probing or silicone-tube intubation. The majority of patients showed symptom improvement (75.2%) during the two months of follow-up.

Conclusions

Dacryoscintigraphy is a non-invasive method of qualitatively and quantitatively diagnosing nasolacrimal duct obstruction in children with tearing.

Lacrimal outflow mechanisms and the role of scintigraphy: current trends

Lacrimal outflow can be compromised by anatomical obstructions or stenoses (nonfunctional epiphora) or by defective lacrimal “pump” function (functional epiphora). Although classic imaging modalities, such as X-ray dacryocystography, computed tomography, or magnetic resonance imaging can effectively evaluate the former, their success is much less in the evaluation of the latter. This is largely due to the fact that forced diagnostic injection of fluid into the canalicular system can overcome partial obstruction sites. On the other hand, lacrimal scintigraphy mimicks “physiological” lacrimal outflow, being performed under pressure gradients present in everyday life. This is why it is considered more suitable for the study of functional epiphora. Furthermore, quantitative lacrimal scintigraphy (with time-activity curves) enables the accurate measurement of lacrimal clearance from the conjunctival fornices and may be used to study the physiology of the lacrimal “pump.” Data obtained from the scintigraphic study of lacrimal outflow may be used to design more effective procedures in the management of functional and nonfunctional epiphora. This is a review article, based on a literature search with emphasis on recent publications and on those supporting interdisciplinary cooperation between ophthalmology and nuclear medicine.

Tear production and drainage after botulinum toxin A injection in patients with essential blepharospasm

PURPOSE

To evaluate the clinical manifestations of tear production, distribution and drainage in the essential blepharospasm patients, and to analyse the changes after botulinum toxin A injection in these patients.

METHODS

This prospective study was performed in 23 patients with essential blepharospasm treated with Botulinum neurotoxin A (BoNT-A; Dysport, Ipsen Biopharm, UK) from November 2010 to February 2011. Ocular examinations, including frequency and severity of blepharospasm, tear break up time (BUT), Schirmer's test, lower lid tear meniscus height (TMH) measured by optical coherence tomography (OCT, rtvue software version 3.5; Optovue Inc., Fremont, CA, USA), and dacryoscintigraphy using 99m technetium pertechnetate, were performed before and 2 weeks after BoNT-A injection. We asked all patients about changes in the dry eye symptom score, before and after treatment. Results were analysed with independent t-test using spss software version 12.0 for Windows XP, (SPSS Inc., Chicago, IL, USA).

RESULTS

Botulinum neurotoxin A treatment relieved blepharospasm in all patients. Mean injection dose was 38 ± 5.6 units. After injection, mean tear BUT was significantly increased from 4.7 ± 4.9 to 6.6 ± 1.6 seconds (p = 0.001) Lower TMH increased in all three points and most notably at the lateral point (p = 0.05). On dacryoscintigraphy, tear drainage velocity was not affected by BoNT-A treatment. But Tc-99m 50% clearance time in interpalpebral fissure significantly increased from 1564 to 2220 seconds on the time activity curve (p = 0.027). Subjective dry eye symptoms also improved in 16 patients (70%) after injection.

CONCLUSION

Tear film stability and TMH increased, but tear drainage velocity was not affected by BoNT-A treatment. Overall Tc-99m 50% clearance time in interpalpebral fissure significantly increased, and tear storage from mild lateral lower eyelid laxity increased after BoNT-A injection. Botulinum neurotoxin A injection was also effective for combined dry eye symptom in the essential blepharospasm patients.

Update on imaging of the lacrimal drainage system

Epiphora is a common problem seen by the ophthalmologist. There are numerous etiologies of a watering eye, and the underlying diagnosis is not always clear. A variety of in-office examination techniques and procedures exist to aid with diagnosis and determination of appropriate therapy, but sometimes the diagnosis remains elusive, or an instituted therapy fails. Lacrimal imaging, particularly in these cases, can be helpful in assessing the function and anatomy of the lacrimal drainage system. This review serves to examine the literature of the last 10 years concerning imaging of the lacrimal drainage system.

Lacrimal scintigraphy: "interpretation more art than science"

Lacrimal scintigraphy (LS) or dacryoscintigraphy can demonstrate abnormalities in 80%-95% of patients with symptoms of epiphora and a patent lacrimal system on syringing and up to 40% asymptomatic individuals. Precise localization of the site of delay may not always be possible due to lack of anatomic detail on LS. LS is considered useful in patients with epiphora with delayed tear clearance and patency to syringing and suspected to have either nasolacrimal duct (NLD) stenosis or lacrimal pump failure. It remains unclear, however, as to whether LS can reliably distinguish between the two. The literature reports considerable variation in the technique, normative data, analysis, and interpretation of LS. Qualitative or visual analysis is simpler to perform and to our knowledge used more frequently in comparison to quantitative analysis. There is little extra information to be gained from LS in cases with complete NLD obstruction or severe NLD stenosis on syringing.

Evaluation of lacrimal tear drainage mechanism using dynamic fluoroscopic dacryocystography

PURPOSE

To evaluate the dynamic change of the canaliculus and the lacrimal sac during blinking using fluoroscopic dacryocystography.

METHODS

Sixteen patients presenting with unilateral epiphora were enrolled in the study. Fluoroscopic dacryocystography was performed in both eyes, and sequential images of the lacrimal drainage system were acquired during blinking. On examination of the contralateral asymptomatic side, the length of the lower canaliculus and the width of the superior and inferior portions of the lacrimal sac were measured and compared between eyelid closure and opening.

RESULTS

The length of the lower canaliculus decreased with eyelid closure in 13 of 16 patients, and the change was statistically significant (p = 0.006, Wilcoxon signed rank test). The width of the superior portion of the lacrimal sac increased with eyelid closure (p = 0.033), but the width of the inferior part did not change significantly (p = 0.679).

CONCLUSIONS

With eyelid closure, the canalicular system contracts, and the superior portion of the lacrimal sac dilates; these may be important parts of the active lacrimal pump mechanism. These findings suggested that the canalicular system and the superior portion of the lacrimal sac play key roles in active tear drainage pump.

A modified Jones test: lacrimal scintigram correlation

PURPOSE

To determine the correlation between lacrimal scintigraphy and a modified Jones primary dye drainage test combined with the fluorescein dye disappearance test (DDT) and Jones secondary dye test, in diagnosing the cause of epiphora.

METHODS

A prospective, consecutive clinical trial was conducted. All patients presenting with epiphora were considered, but those with trichiasis, corneal irritation, lower eyelid ectropion, Bell palsy, or previous lacrimal surgery were excluded. A cohort of 39 patients (65 eyes) underwent the fluorescein DDT and the senior author's (R.B.) modified Jones primary dye drainage test (Jones dye test 1 [JDT1]). For this test, an entire fluorescein 2% Minim dose was instilled in the 2 eyes, and the patient was then asked to gently blow each nostril separately in a white tissue; the degree of fluorescein staining was noted. If there was no fluorescein staining of the tissue (negative JDT1), a traditional Jones secondary dye test (Jones dye test 2) was also performed. All patients except for those testing strongly positive on modified testing or with negative DDT and JDT1 and nil drainage from the nose in Jones dye test 2, indicating anatomical obstruction, were referred for lacrimal scintigraphy.

RESULTS

In total, 59 of 65 eyes (91%) showed a positive correlation between the diagnosis arrived at after dye testing using the modified primary dye test and diagnosis on lacrimal scintigraphy. The interrater reliability for the raters was found to be κ = 0.770 and 95% confidence interval = 0.594-0.945. The strength of agreement is considered to be "good."

CONCLUSIONS

The authors found that in the presence of patent lacrimal drainage system dysfunction, modified Jones primary dye test, combined with the fluorescein DDT and Jones secondary dye test, correlated strongly with lacrimal scintigraphy.

Nanoscale phase dynamics of the normal tear film

The tear film is a dynamic multilayered structure. The interactions and the interfacial dynamics between the layers that occur during a blink cycle must be such that they allow for maintenance of a stable tear film. Attempts to understand these dynamics have been limited by the techniques and biomarkers used. Quantum dots (qdots) offer a new potential to monitor the dynamics of the tear film layers in vivo without the drawbacks of previously used methodologies. Indium phosphide-gallium qdots were used to differentially assess the dynamics of the lipid and aqueous layers of the tear film in real time. In the aqueous, qdots dispersed to form a stable local region that was swept away into the upper and lower menisci during a blink. They did not redisperse onto the ocular surface but were progressively removed from the menisci through the puncta. Some of these qdots adhered to the mucin layer on the ocular surface in a meshlike pattern and remained there for five to six blinks before they were removed. The organic qdots dispersed quickly but patchily over the whole outer surface of the tear film. They also strongly marked both eyelid margins and slowly dispersed onto the skin and eyelashes and not through the puncta. Some were trapped in the menisci as blobs that rolled along the meniscus. These data support the view of a distinct three-layered tear film: an inner mucin layer attached to the epithelial cells, a fluid aqueous layer, and an outer viscoelastic lipid layer.

Evaluation and management of congenital nasolacrimal duct obstruction

Congenital nasolacrimal obstruction is a common disorder in infants that results in persistent tearing and may lead to infections, such as dacryocystitis, orbital cellulitis, and bacterial conjunctivitis. The true incidence of this disorder in healthy newborns remains controversial. The most frequently quoted number of 6% comes from a study of 200 consecutive live births in the 1940s in which nasolacrimal patency was assessed by the presence or absence of discharge on compression of the lacrimal sac. Estimates from other studies, which often use different criteria for diagnosis, vary considerably from 1.2% to 30%. The incidence of the disorder is higher in children who have craniofacial disorders and Down's syndrome. This article reviews the causes and treatment of congenital nasolacrimal obstruction.

Radiologic Evaluation of Lacrimal and Orbital Disease

This article discusses the evaluation of specific lacrimal disorders and orbital trauma using CT, MRI, and other radiologic techniques.

Lower Eyelid Laxity in Functional Acquired Epiphora: Evaluation With Quantitative Scintigraphy

PURPOSE

The examination of lacrimal drainage is often based on qualitative criteria. This study uses quantitative scintigraphy to evaluate "functional" epiphora.

METHODS

Thirty-two patients with functional epiphora (no morphologic abnormalities of the conjunctiva and eyelids, a patent nasolacrimal duct on irrigation, and no anatomical stenosis on dacryocystography) were studied (study group, SG). Twenty-two individuals without epiphora were also examined (control group, CG). Fifty microliters of Technetium-99m was instilled into the conjunctival cul-de-sac. Time-activity curves were then constructed, and conjunctival lacrimal clearance (CLC) at 2.5, 5, 7.5, and 10 minutes was calculated. Differences in CLC between the SG and the CG and correlations between CLC and horizontal and median tendon laxity and eyelid length in the SG were examined.

RESULTS

The SG had significantly reduced CLC at 2.5 and 5 minutes, compared with the CG (p = 0.01 and p = 0.04, respectively), whereas respective differences at 7.5 and 10 minutes were not statistically significant. In the SG, CLC at 2.5 and 5 minutes was significantly correlated with horizontal and median tendon laxity. The respective correlation with eyelid length was not statistically significant. Furthermore, in the SG, CLC at 2.5 and 5 minutes was significantly correlated with patient age (p = 0.03 and p = 0.04, respectively). Differences in CLC between men and women were not statistically significant at all intervals.

CONCLUSIONS

The correlation between eyelid laxity and CLC supports the role of the eyelid "pump" in lacrimal drainage. CLC at 2.5 and 5 minutes may be used to decide treatment methods for functional epiphora.

A mathematical model for tear drainage through the canaliculi

PURPOSE

Tear drainage through the canaliculi has been extensively studied experimentally but there has been no attempt to develop a quantitative model for this process. In this paper, we develop a mathematical model for the tear drainage through the canaliculi.

METHODS

The mathematical model is based on the experimental findings of Doane, according to which the muscle action during a blink drives the tear drainage. In this paper, mathematical models are developed for the tear flow and the canalicular deformation, and the model equations are solved to predict the tear drainage rates.

RESULTS

The drainage rates depend on various physiological parameters. The time to attain a steady state during the drainage process can vary from about 0.0010 s to 0.0546 s, and the tear drainage rate can vary from 0.10 microl/min to 4.00 microl/min for a normal tear film, for physiologically reasonable values of various system parameters.

CONCLUSIONS

The model predictions agree with various physiological experiments, at least qualitatively. The model also helps resolve the differences between various tear drainage experiments.

The clinical value of dacryoscintigraphy in the selection of surgical approach for patients with functional lacrimal duct obstruction

PURPOSE

Dacryoscintigraphy is widely known to be an effective modality in diagnosing abnormalities of the lacrimal system that cause epiphora (pathological overflow of tear). However, dacryoscintigraphy rarely serves beyond the simple diagnostic use for lacrimal duct obstruction. In our study, dacryoscintigraphy results of patients with functional lacrimal duct obstruction are newly classified into three types, the effects and prognoses of silicone tube intubation are noted according to each type, and the role of dacryoscintigraphy in determining appropriate surgical approaches is evaluated.

METHODS

Subjects were 36 eyes of 29 patients complaining of epiphora who had increased tear meniscus, but showed no sign of obstruction on duct syringing. Impression of functional lacrimal duct obstruction was made through dacryoscintigraphy, and silicone tubes were inserted.

RESULTS

Patients were classified according to the results of dacryoscintigraphy; those with delayed secretion in the distal nasolacrimal duct were typed as class I; those with delays in the proximal nasolacrimal duct class II; and delayed secretion from the pre-lacrimal sac to the lacrimal sac as class III. All patients had silicone tube intubations together with selective punctoplasty. Symptomatic improvement was observed in all 6 cases of distal nasolacrimal duct obstruction (100%), 14 of 18 proximal obstruction cases (77.8%), and 8 of 12 pre-lacrimal obstructions (66.7%).

CONCLUSIONS

Functional lacrimal duct obstruction is easily diagnosed with dacryoscintigraphy. Furthermore, its may be classified by types of obstruction to predict post-operative results of silicone tube insertion. Cases suspicious of pre-lacrimal sac obstructions in particular may achieve better operative results with adjuvant treatments in addition to silicone tube insertion.

Silicone versus collagen plugs for treating dry eye: results of a prospective randomized trial including lacrimal scintigraphy

PURPOSE

To compare the short-term efficacy of collagen and silicone plugs for treating dry eye using quantitative lacrimal scintigraphy.

DESIGN

Prospective randomized clinical trial.

METHODS

In this institutional study, 24 dry eye patients were evaluated in two groups: group I (n = 22 eyes) received collagen plugs and group II (n = 26 eyes) received silicone plugs. Comparisons were made with normal control subjects (n = 22 eyes). Data for the Schirmer I test, tear break-up time, and ocular surface staining with rose bengal dye were recorded before and after punctal occlusion. Lacrimal scintigraphy was performed at each time point, and the time to half maximum activity on the ocular surface (T(1/2)), and the percentage retention of activity on the ocular surface at the end of the dynamic study (RI) were recorded.

RESULTS

In both patient groups, Schirmer I results, tear break-up times, and rose bengal staining scores improved significantly after plug insertion. Mean T(1/2) values and RI values increased significantly in both groups (P < .0001 for both). The differences for these values between groups I and II was statistically insignificant (P > .05).

CONCLUSIONS

Collagen and silicone plugs both resulted in significant increases in aqueous tear volume, half-life of nuclear material on the ocular surface, and percentage of nuclear material retention. The groups' post-insertion values for all parameters were similar. These results suggest that these two plug types have similar efficacy as treatments for dry eye in the short term. Further studies evaluating long-term results are required.

Clinical value of dacryoscintigraphy using a simplified analysis

PURPOSE

To study the discriminatory ability of dacryoscintigraphy in differentiating between patients with epiphora and volunteers using a simple method.

METHODS

Twenty eyes in ten volunteers and 66 eyes in 55 patients with severe epiphora were studied. Dacryoscintigraphy (15 frames of 1 min) was performed after administration of 4 MBq (99m)Tc-pertechnetate (10 mul) in both eyes. By mapping a single region of interest (ROI) over the conjunctival sac we determined T1 (%dose in first minute) and linear clearance rate (LCR, defined as [see text] from the tracer disappearance curve. Reproducibility was determined in volunteers. Conjunctival resorption was determined from completely obstructed systems. Sensitivity and specificity were calculated and receiver operating characteristics (ROC) analysis was conducted.

RESULTS

In volunteers mean T1 was 52.8+/-11.9% (95% CI 47.1-58.4%), and LCR was 74.2+/-11.1% (95% CI 69.0-79.4%). Reproducibility was good (mean difference 4.1+/-13.3% for T1 and 0.7+/-17% for LCR). Epiphora patients had clearly higher T1 (82.1+/-15.2%, P<0.0001) and lower LCR (38.9+/-22.5%, P<0.0001) values. Tracer resorption was 24%. Based on ROC analysis 70% for T1 and 50% for LCR were considered optimal cut-off levels to separate patients from volunteers. Sensitivity/specificity were 77/95% for T1 and 71/100% for LCR. T1 and LCR values did not correlate with symptom scores or Anel test results.

CONCLUSION

Dacryoscintigraphy, using LCR and T1 as parameters, is a reliable and objective method to detect tear-flow abnormalities.

Assessment of Tear Film Dynamics: Quantification Approach

The dynamics of the tear film are reviewed with specific reference to the biophysical aspects: distribution, turnover and elimination through evaporation, drainage, and absorption. The review concentrates on quantitative assessments and is confined to aspects of the dynamics that can be fully and directly measured. The techniques of fluorophotometry, fluorescein clearance, lacrimal scintigraphy, evaporimetry and osmometry are described. Reports in the literature for values of tear turnover (flow), evaporation and osmolarity for normal and dry eyes are collated. Indices of tear film dynamics based on these measurements, including tear function index, total tear flow, and osmolarity, are discussed in relation to their potential in the differential diagnosis of dry eye and new referent values for the disease suggested. The limitations of derivation and application of these indices are discussed.

Ultrasonic visualization of the effect of blinking on the lacrimal pump mechanism

BACKGROUND

The role of the lacrimal sac (LS) and the medial canthal tendon in the lacrimal pump mechanism is controversial. This study used ultrasonic visualization to analyze this phenomenon.

METHODS

Movements of the LS and the medial canthal tendon during blinking were visualized with sonography. In addition, the maximal profile area of the LS was measured before and after blinking using 15-MHz sonography in 14 individuals with a normal lacrimal drainage system and in six patients with lacrimal duct obstruction.

RESULTS

The upper part of the LS could be located as an echolucent structure between the lacrimal bone and the medial canthal tendon. The medial canthal tendon appeared to compress the LS during lid closure and release the LS during lid opening. The measured profile area of the visible normal LS at the compression time decreased by 50%. The dilated LS of patients with obstruction could also be compressed by the orbital muscle on blinking, but the maximum area decrease was only 15.5%.

CONCLUSION

The findings imply that the lacrimal part of the orbicularis muscle contracts during blinking, with the medial canthal tendon compressing the LS in a cranial direction. Completion of lid closure then compresses both canaliculi and LS, forcing the intrasacral fluid through the drainage system. The expansion of the LS during the opening phase of the blink causes suction, and after opening of the punctal areas the canaliculi and LS vacuum breaks to reload with tear fluid. These findings demonstrate the importance of the orbicularis muscle and the medial canthal tendon for the lacrimal pump mechanism during blinking.

Pathology and Imaging of the Lacrimal Drainage System

The lacrimal drainage apparatus drains tears from the eye. The system is susceptible to a multitude of pathologic findings, including obstruction, infection, inflammation, and neoplasms. The diagnosis of several of these processes is aided by the use of radiologic studies. In conjunction with dacryocystography, cross-sectional modalities, such as CT and MR imaging have improved the ability of diagnostic imaging to characterize the obstructive nature and soft tissue or osseous changes of various disease processes.

Presurgical and postsurgical ultrasound assessment of lacrimal drainage dysfunction

PURPOSE

In addition to the obligatory clinical tests, imaging of the lacrimal drainage system (LDS) is useful in its clinical evaluation. The purpose of this study was to examine the usability and reliability of ultrasonography in the evaluation of the lacrimal drainage system.

DESIGN

Observational cohort study.

METHODS

A prospective study was conducted at a single institution. We performed ultrasound examinations on 17 patients with epiphora before and after surgery, and on 17 asymptomatic volunteers, to visualize and evaluate the anatomic and functional condition or pathologic abnormalities of the LDS.

RESULTS

Echographic evaluation of the LDS was possible in all individuals. Pathologic abnormalities (canaliculitis, diverticulitis, concretion, or dilation of the lacrimal sac, and reduced functionality of the orbicular muscle and/or lacrimal sac pump) could be well demonstrated. In the postsurgical course, functional patency of the dacryocystorhinostomy opening could be verified in all cases.

CONCLUSIONS

Sonography of the LDS appears to represent a reliable diagnostic technique supplementary to clinical tests in the presurgical and postsurgical examination of patients with epiphora. Pathologic abnormalities that may not be apparent in routine x-ray dacryocystography can be demonstrated with ultrasound techniques. Patients also benefit from the avoidance of exposure to ionizing radiation. However, ultrasound is not suitable for imaging the lower part of the lacrimal sac and the lacrimal duct because of the presence of overlying bony structures.

Determination of relative contribution of the superior and inferior canaliculi to the lacrimal drainage system in health using the drop test

PURPOSE

The aim of this study was to explore the use of the 'drop test' as a method of assessing maximal lacrimal outflow capacity, and to measure the relative contribution of the superior and inferior canaliculi to the drainage capacity in normal subjects.

METHOD

The drop test involves instilling measured aliquots of normal saline over 3-min periods to raise the tear lake medially. Both eyes were assessed; however, for the right lacrimal drainage system only, sequential insertion and then removal of silicone punctal plugs was performed. After each stage the maximal lacrimal drainage capacity was measured. no punctal plugs were placed in the puncta on the left side.

RESULTS

Complete data were collected from 20 subjects with a mean age of 35.6 years. The intraclass correlation coefficient for the five left eye readings was 0.98 (CI 0.96-0.99) and the limits of agreement of a single reading were -22.6 to +93.0 micro L/3 min. Without intervention, no statistically significant difference was found in the mean lacrimal outflow between the left and right eyes (P = 0.16). A statistically significant reduction in outflow resulted from punctal occlusion (P < 0.05). Presenting the proportion of lacrimal outflow as a percentage of the combined values of the superior and inferior canaliculi, 59.9% of outflow occurred through the inferior canaliculus.

CONCLUSION

The drop test was found to provide a simple and repeatable method of assessing lacrimal drainage in a minimally invasive manner in the clinical setting. In healthy volunteers in the supine position 60% of maximal lacrimal outflow capacity occurs through the inferior canaliculus.