Endoscopic Anatomy of the Lacrimal Sac: A Cadaveric Study.

OBJECTIVE: To describe the anatomy of the lacrimal sac in relation to the lateral nasal wall by cadaver dissection, and to measure the distances of surgically important landmarks from relevant structures for safer and more efficient surgery. METHOD: A total of 12 endoscopic dacryocystorhinostomy (DCR) were performed on both sides (right and left) of 6 fresh-frozen cadavers. The distances of the lacrimal sac to the posterior edge of the uncinate process, the frontal process of the maxilla, the maxillary ostium, the nasal vestibule, the middle turbinate attachment and the inferior turbinate were measured. In addition, the width and length of the lacrimal sac were measured. RESULTS: The mean width and length of the lacrimal sac were 5.6 mm and 11.1 mm, respectively. The lacrimal sac was located at 15.2 mm from the posterior edge of the uncinate process, at 35.5 mm from the nasal vestibule, at 13.5 mm from the maxillary ostium, at 12.2 mm from the frontal process of the maxilla, at 8.7 mm from the middle turbinate attachment, and at 7.3 mm from the inferior turbinate. CONCLUSION: This study provides additional measurements regarding the lacrimal sac and its relationships with nearby landmarks for use in endoscopic dacryocystorhinostomy. The distances of the lacrimal sac to the nasal vestibule, the uncinate process and the frontal process of the maxilla are not as reliable as the middle turbinate attachment for predicting the anatomic localization of the lacrimal sac during DCR.

New insights into the lacrimal pump.

PURPOSE: To date, there are many theories about tear transport through the canaliculi of the draining lacrimal system into the lacrimal sac but only few with supportive data. It is certain that the function of the lacrimal part of orbicularis oculi muscle (Horner-Duverney's muscle) is indispensable for the transport of "used" tears. However, the muscle's exact structure and the mechanisms of its functions are as yet unclear. To obtain deeper insights we undertook the present study. METHODS: Upper and lower canaliculi (including the entrance into the lacrimal sac) from donor cadavers were dissected. Some of the specimens were prepared for scanning electron microscopy (SEM) to analyze the course of muscle fibers surrounding the canaliculi. Others were sectioned for enzyme- (EHC) and immunohistochemistry (IHC) to learn about the distribution of slow and fast reacting muscle fibers in Horner-Duverney's muscle as well as to analyze the distribution of different neurotransmitters to learn more about the innervation of Horner-Duverney's muscle. Four tear duct systems taken from body donors were cut out en bloc after formalin fixation, serially sectioned and reconstructed using a newly developed technology for 3D reconstruction of histological serial sections named HiD® (Chimaera GmbH, Germany). Patients that had undergone dacryocystorhinostomy (DCR) were video-analyzed endonasally during active blinking, focusing on viewing the temporal wall of the lacrimal sac movement where the canaliculi penetrated the lacrimal sac. RESULTS: SEM revealed that muscle fibers of Horner-Duverney's muscle surround the vertical parts of the upper and lower canaliculus in a scissor like pattern whereas they ran in parallel to the first two thirds of the horizontal parts surrounding the respective canaliculus. Here, the muscle fibers were embedded in dense connective tissue forming a unique network. At the nasal third, muscle fibers left the canaliculi and ran to the posterior part of the fascia of the lacrimal sac and the lacrimal bone. EHC revealed that Horner-Duverney's muscle contained nearly an equal distribution of type I and type IIb muscle fibers compared to the superior rectus muscle which contains more type I and the masseter and iliopsoas muscles with more type IIb muscle fibers. IHC indicated presence of trigeminal, catecholaminergic and cholinergic nerve endings. 3D reconstructions supported the SEM data. Endonasal video analysis of patients after DCR with a nasally open lacrimal sac revealed bulging of the temporal wall of the lacrimal sac during blinking. On the basis of these findings, a modified lacrimal pump theory is proposed. CONCLUSION: The results support the hypothesis that contraction of Horner-Duverney's muscle leads to closure of the canaliculi in their first two thirds based on the special arrangement of muscle fibers and connective tissue fibers. This causes the tear fluid in the canaliculi to be pressed/transported towards the lacrimal sac. The medial third of the vertical portions of the canaliculi, the canaliculus communis and the intrasaccal portion of the canaliculus are compressed by the shortening and thickening of the Horner-Duverney muscle from dorsal, which leads to a compression of the canaliculi lumens in this part of the system, thereby pushing the lacrimal fluid further towards the lacrimal sac. The mix of fast contracting and fatigue resistant muscle fibers is ideally suited for the blink mechanism that is complexly regulated by the nervous system.

Adding myofibroblasts to the lacrimal pump.

The lacrimal sac (LS) empties in the nasolacrimal duct to drain the tears in the inferior nasal meatus. Different studies indicated the role of the lacrimal pump in the lacrimal drainage. Although controversial, the lacrimal pump mechanism is an extrinsic one, either active, or passive. An intrinsic contractile potential of the LS was not documented previously. We thus aimed a retrospective immunohistochemical study to test the alpha-smooth muscle actin (α-SMA) and h-caldesmon expression in the LS wall. We used archived paraffin-embedded samples of LS from ten adult patients. The α-SMA + phenotype was detected in basal epithelial cells, in subepithelial ribbons of stromal cells, in vascular smooth muscle cells, as well as in pericytes. H-caldesmon was exclusively expressed in pericytes, vascular smooth muscle cells and myoepithelial cells of the subepithelial glands. The most striking feature we found in all samples was a consistent stromal network of α-SMA+/h-caldesmon- myofibroblasts. This finding supports an intrinsic scaffold useful for the lacrimal pump.

Use of the Crawford tube for symptomatic epiphora without nasolacrimal obstruction.

AIM: To evaluate the effectiveness of the Crawford tube in treating symptomatic epiphora without nasolacrimal obstruction. METHODS: A protocol was adopted for the management of symptomatic epiphora without nasolacrimal obstruction. Patients who suffered symptomatic epiphora without nasolacrimal obstruction in both eyes were included in the study. One eye was treated with Crawford tube intubation and the other eye was treated with medication therapy. Degree of watering, patient satisfaction, and symptomatic improvement were carefully evaluated by one of the authors at the end of the follow-up period, after Crawford tube removal, to ascertain functional results. RESULTS: Thirty-seven adult patients (37 eyes) underwent Crawford tube intubation for functional epiphora. The mean follow-up time after removal of the tube was 14.8±4.8mo. The procedure was an overall success in 28 eyes (75.7%), with symptoms improving significantly. Two eyes (5.4%) were relieved of indoor epiphora, two (5.4%) had minimal epiphora outdoors, but only with wind or cold, and five (13.5%) continued to experience tearing both indoors and outdoors. Thirty of the patients (81%) expressed satisfaction with the procedure. CONCLUSION: Crawford tube insertion is an effective, safe, simple, and relatively noninvasive treatment strategy for functional lacrimal system obstruction.

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.

Medial blepharosynechioplasty: a new surgical concept for severe dry eye.

BACKGROUND: The purpose of this work was to report on the performance of medial blepharosynechioplasty (MBSP), a newly devised technique for treating severe dry eye. METHODS: In this retrospective, nonrandomized clinical trial, three cases with severe dry eye (Sjögren's syndrome) associated with repeated punctal plug loss were treated using MBSP to create a synechia between the upper and lower lid medial borders of the puncta to suppress the lacrimal pump. RESULTS: Postoperative follow-up showed improvement in the corneal condition in all three cases that persisted for 12-35 months. None of the patients had visual impairment. CONCLUSION: MBSP is a promising treatment for severe dry eye and merits further study.

The Effects of Transcanalicular Diode Laser-Assisted Revision Surgery for Failed Dacryocystorhinostomy

PURPOSE: To determine the intranasal causes of failed dacryocystorhinostomy (DCR) and the effects of transcanalicular diode laser-assisted revision surgery. METHODS: Twenty-four patients (29 eyes) who underwent revision surgery for a failed DCR at the Department of Ophthalmology, Ansan Hospital, Korea University between March 2009 and February 2011 were included in the present retrospective study. The intranasal causes of failed DCR, the time of symptoms such as epiphora and discharge after DCR, success rates of revision surgeries and follow-up periods were evaluated. RESULTS: Membranous obstruction was found in 25 eyes (86.2%) and was accompanied with granuloma in 10 eyes; these were the most common causes of failed DCR. The mean time for symptom development after DCR was 14.6 months, the success rate of the first revision surgery was 82.1% and good results were obtained in 5 eyes after the second revision surgery. Recurrence developed in 2 eyes, but symptoms improved after the lateral tarsal strip procedure. CONCLUSIONS: Membranous obstruction was the most common intranasal cause of failed DCR and transcanalicular diode laser-assisted revision surgery produced good results. Additionally, in patients with persistent epiphora following anatomically-patent revisional surgery, lacrimal pump failure due to lower eyelid laxity should be considered and corrected.

Lateral Tarsal Strip Procedure and Silicone Tube Intubation on the Functional Nasolacrimal Duct Obstruction

PURPOSE: To compare the effects of the lateral tarsal strip procedure alone and the lateral tarsal strip procedure combined with silicone tube intubation in the treatment of functional lacrimal duct obstruction. METHODS: The present study investigated 27 eyes of 20 patients underwent lateral tarsal strip procedure (LTS) alone and 29 eyes of 18 patients underwent combined lateral tarsal strip procedure and silicone tube intubation and who were diagnosed with functional lacrimal duct obstruction. The authors retrospectively reviewed patients' medical records for information including age, gender, history, follow-up period, tear meniscus height (TMH), and symptoms. RESULTS: The average age of the LTS alone group was 60.3 years, and that of the combined groups was 65.9 years. The TMHs in the LTS only and combined operation groups were 0.62 +/- 0.23 mm and 0.62 +/- 0.19 mm before the operation and 0.43 +/- 0.20 mm and 0.26 +/- 0.09 mm after the operation, respectively. The postoperative improvement in epiphora was 74.1% after the LTS alone and 86.2% after combined LTS with silicone tube intubation. The postoperative improvement in epiphora and the operative technique of the lateral tarsal strip-canthus sparing or cantholysis were not relevant. CONCLUSIONS: Lateral tarsal strip combined with silicone tube intubation appeared useful in the treatment of epiphora patients without anatomic lacrimal duct obstruction. Determining which operative technique of lateral tarsal strip procedure should be chosen is difficult, and the preoperative syringing and snap back test may be helpful.

The Effects of Lateral Tarsal Strip Procedure on the Functional Nasolacrimal Duct Obstruction

PURPOSE: To evaluate the effects of the lateral tarsal strip procedure in the treatment of lacrimal pump dysfunction related to lower lid laxity. METHODS: This study investigated 46 eyes of 35 patients diagnosed with dysfunction of the lacrimal pump on which the lateral tarsal strip procedure was performed between June 2001 and February 2004. We retrospectively reviewed patients' medical records for information including age, gender, history, follow-up period, change of fluorescein dye disappearance test (DDT), tear meniscus height (TMH), symptoms, and complications. RESULTS: Improvement of tearing was noted in 26 patients (78.8%). Thirty-seven eyes (80.5%) were improved by more than 1 grade on DDT. Significant improvement above 2 grades was observed in 16 eyes (34.7%). With respect to age, 62.5% of 3rd-decade patients improved most effectively by more than 2 grades on DDT. Postoperative TMH compared with preoperative TMH measures were significantly lower according to statistics. The most common complication was discomfort or tenderness over the orbital rim (13.0%). CONCLUSIONS: Performance of the lateral tarsal strip procedure for tearing caused by dysfunction of the lacrimal pump and related to lower lid laxity improved patients' tearing, DDT and TMH status. We therefore expect the lateral tarsal strip procedure to be effective in the surgical treatment of lacrimal pump dysfunction secondary to lower eyelid laxity.

The Clinical Evaluation on the Patients Complaining of Epiphora

The clinical analysis on the etiologies was done along with frequency of the patient's complaints of epiphora.The etiologies of the fifty-four patients screened by fluorescein dye disappearance test were classified by the causative location of the lacrimal pathway. The average of the patient's ages was 48.7 years old and average duration of symptom was 26.1 months.The causative locations were punctum[35.2%], nasolacrimal duct, lacrimal pump and nasal cavity in following order.The most common causes of each group were senile lid laxity[5.6%] for lacrimal pump, conjunctivochalasis and punctual atresia[11.1%]for lacrimal pump, idiopathic narrowing[9.3%]for canaliculus and idiopathic narrowing[16.6%]for nasolacrimal duct.Probing was the most common past history[18.5%]and the kinds of treatment were dacryocystorhinostomy, punctoplasty, lid tightening, probing, and conjunctivod acryocystorhinostomy. These data are expected to be a useful guide of rapid diagnosis and appropriate treatment for the epiphora patients without complicate processes and discomfort.

Efficacy of Dacryoscintigraphy in Patients with Functional Block of Lacrimal Drainage System

To evaluate the diagnostic efficacy of dacryoscintigraphy, we examined Hones dye test and dacryoscintigraphy in 24 eyes of 18 patients who were suspected to have junctional block in lacrimal drainage system. Among 18 eyes that were negative to Jones I dye test, 3 showed punctal stenosis and 6 typical pattern of lax lid and 2 partial obsturction of nasolacrimal duct on dacryoscintigraphy. In evaluation of lacrimal drainage system, physiological aspect is as important as anatomical information since lacrimal pumping action of lid and tear flow as well as the patency of lacrimal passage contribute to the lacrimal drainage. Compared to Jones dye test, dacryoscintigraphy is more useful with certain advantages : It gives less discomfort to patients, provides anatomical information and does not depend on examiner`s skills.