All patients with chief symptoms of watery eye and discharge in Menoufia university hospitals were evaluated and only patients with primary acquired NLDO were considered. All other secondary causes of NLDO were excluded, including but not limited to, chronic granulomatous inflammation, chronic dacryocystitis, atrophic sac, lacrimal sac malignancy, nasal causes as deviated nasal septum, nasal polyps or atrophic rhinitis and traumatic bony deformity in the nasal region. In addition, patients with entropion, ectropion, lid laxity, canalicular and common canalicular obstruction were excluded from the study.
From June 2012 to July 2014, fifty-six patients who with primary acquired NLDO were eligible for the study. They were counselled for enrollment in the study. Enrolled patients signed a well-informed consent and were randomly allocated into two groups: group A (30 cases) for external DCR and group B (26 cases) for silicone intubation with MMC. All study procedures were carried out in accordance with declaration of Helsinki and were approved by the institutional ethical committee.
Enrolled patients were thoroughly examined with particular reference to the lacrimal apparatus. Nasal examination was accomplished by ENT specialist, essentially to rule out significant deviation of nasal septum of hypertrophied turbinate or nasal polyps. Preoperatively, anatomical and physiological patency of the lacrimal drainage system was evaluated with lacrimal syringing and dye disappearance test respectively.
Thirty patients underwent external DCR under general anesthesia with standard sterilization procedures. Ipsilateral nasal cavity was packed by roller gauze soaked in adrenaline 1:200,000. Five milliliters of adrenaline 1:200,000 were infiltrated around lacrimal sac for hemostasis. A curvilinear incision of 10-15 mm length was made along the anterior lacrimal crest starting 3 mm above the medial palpebral ligament and 3mm medial to medial canthus.
The orbicularis oculi muscle fibers were separated with artery forceps and with blunt dissector. Cat’s paw retractors were used to retract the edges of incision. With the help of Traquair’s periosteal elevator, the periosteum overlying and medial to the anterior lacrimal crest was exposed and elevated. The sac was separated from the lacrimal fossa with a blunt dissector
The smaller end of the blunt dissector was used to fracture Lamina papyracea, the parchment like bone of the posterior half of the lacrimal fossa. the nasal mucosa was stripped from lacrimal bone with the help of Traquair’s periosteal elevator, to avoid damage to the nasal mucosa. An osteotomy of approximately 12.5 x10mm was created with successive punching of bone by Cittelli’s punch. Oozing of blood was controlled by packing with ribbon gauze and suction.
The upper punctum was dilated with Nettleship’s punctum dilator, the position of the common canaliculus and related part of the medial sac wall is confirmed by Bowman’s probe which was passed through the upper canaliculus to confirm the position. Lacrimal sac and nasal mucosa were opened in an ‘H’ fashion with the no.11 Bard-Parker blade and Bowman’s probe was in place, to form a large anterior and smaller posterior flap. The Bowman’s probe was removed. Posterior flaps sutured and then anterior flaps.
The orbicularis muscle was closed using 6-0 vicryl with interrupted sutures. The skin incision was closed by with running subcuticular suture using 6-0 vicryl. Antibiotic ointment was instilled into the eye, the wound dressing with betadine-soaked gauze and a pressure bandage applied.
Twenty-six patients underwent canalicular silicone intubation with MMC under general anesthesia. Cotton soaked in adrenaline 1:200,000 was packed in the nose. The inferior and superior puncta were dilated, then Bowman’s probe was gently inserted into the inferior canalicular system, until a hard stop was felt in the lacrimal sac, after which it was rotated into the NLD to reach below the inferior concha. The probe was then withdrawn via the inferior punctum and the process was repeated for the upper canaliculus.
After irrigation with normal saline to confirm duct patency, irrigation was performed by introducing 1 ml of MMC (0.5 mg/ml) into the duct with a syringe, the ocular surface then irrigated with 10 ml of normal saline. Cotton tipped applicator was placed in the nasal cavity before irrigation to absorb excess fluid to minimize systemic absorption. Intubation was done by a silicone tube connected by each of its end to a malleable steel guide. A grooved director was placed under the inferior turbinate to guide the probe out of the nose, after which the steel guide was cut from the silicone tube. The procedure was then repeated through the other punctum. The two silicone tubes were tied together with polypropylene 6.0 sutures and fixed to the lateral wall of the nose.
External DCR patients were given systemic antibiotics and analgesics for 5 days. Topical antibiotics were instilled 5 times daily for 7days.The nasal pack was removed after 24 hours; the first dressing was done at 24hrs. Incision area inspected for any gaping, wound infection or discharge. Sutures were removed at 1 week postoperative. For Intubation patients, topical steroids and antibiotics were applied 5 times daily for 2 weeks. The silicone tubes remained in situ for 3 months, and then were removed.
Follow up visits were arranged at 1 week, 1 month, 3 months and 6 months after the surgery. Patients were evaluated subjectively (watering and discharge) upon which were classified as asymptomatic (no watering, no discharge), improvement or no improvement. Objectively, patency of lacrimal passage was tested by height of tear meniscus and lacrimal syringing. On the basis of subjective and objective evaluation, patients were categorized into three groups: successful surgery (asymptomatic, normal tear meniscus and patent lacrimal system with syringing procedure), improvement (watery eye and/or discharge, moderate tear meniscus and partially patent lacrimal system with syringing procedure with mild regurgitation from the puncta) and failed surgery (watery eye and/or discharge, high tear meniscus and non-patent lacrimal system).
Statistical analysis was performed with IBM SPSS for Windows (Version 22.0, Armonk, NY: IBM Corp). Categorical data were expressed as numbers and percentage, while numerical variables were expressed as mean ± SD. Normality of data variables was checked. For normally distributed data, student t-test was used to compare the means between both study groups. Chi-square test was used to compare the categorical variables between both groups.