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 Table of Contents  
ORIGINAL ARTICLE
Year : 2015  |  Volume : 108  |  Issue : 3  |  Page : 102-109

A new permanent lacrimal stent: evaluation of a modification to dacryocystorhinostomy


Research Institute of Ophthalmology, Oculoplasty Unit, Ophthalmology Department, Cairo, Egypt

Date of Submission08-Sep-2014
Date of Acceptance15-May-2015
Date of Web Publication30-Oct-2015

Correspondence Address:
Dikran G Hovaghimian
17 Roushdy Street, #2 Midan Safir, Heliopolis, Cairo 11361
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2090-0686.168659

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  Abstract 

Aim of the work
The aim of this study was to evaluate the effectiveness of a new permanent lacrimal silicone stent - maintaining a patent passage from the medial wall of the lacrimal sac to the nasal cavity through a bony ostium - in the management of chronic dacryocystitis and epiphora as a simple, quick, and effective procedure.
Design
This was an interventional study.
Patients and methods
Thirty-two eyes of 28 patients attending Research Institute of Ophthalmology (RIO), complaining of epiphora due to chronic dacryocystitis or previously failed conventional dacryocystorhinostomy (DCR) surgery, are operated upon using this new modification. All patients underwent surgery in the operating theatre. The selection criterion included patients with chronic dacryocystitis, failed previous DCR, or with chronic epiphora having nasolacrimal duct obstruction with patent canalicular system. All cases were destined for classic DCR. There was no sex choice, race preference or age limitation. The only exclusion criterion was young children below the age of 3 years.
Results
The majority of the patients (71.4%) were women, with a male to female ratio of 2: 5. The mean age of the patients was 38 years ranging between 19 and 61 years. They were 13 right and 19 left eyes. There were four bilateral cases. The mean postoperative follow-up period to determine the success and failure was 9.5 months with a range between 7 and 14 months. In all, 15.6% of patients needed syringing once, whereas 3.1% of patients needed syringing twice after the surgery. The overall success rate of the surgery with complete resolution of epiphora was 96.9% and failure of the procedure in 3.1% of cases. It was also noticed that the failure in surgery as well as the patients who needed syringing were cases that underwent surgery as a secondary procedure as compared with cases where the procedure was done as a primary procedure.
Conclusion
Modified DCR with the new lacrimal silicone stent is technically quick and easy to perform and can be done for all age groups with a high success rate and could be considered as a good alternative to classic DCR surgery.

Keywords: Dacryocystitis, modified external dacryocystorhinostomy, permanent lacrimal silicone stent


How to cite this article:
Hovaghimian DG, Abou Sedira KA, Farag MY, Hamed AA. A new permanent lacrimal stent: evaluation of a modification to dacryocystorhinostomy. J Egypt Ophthalmol Soc 2015;108:102-9

How to cite this URL:
Hovaghimian DG, Abou Sedira KA, Farag MY, Hamed AA. A new permanent lacrimal stent: evaluation of a modification to dacryocystorhinostomy. J Egypt Ophthalmol Soc [serial online] 2015 [cited 2022 Sep 28];108:102-9. Available from: http://www.jeos.eg.net/text.asp?2015/108/3/102/168659


  Introduction Top


Nasolacrimal duct obstruction is one of the commonest diseases affecting the lacrimal drainage system. Persistent tearing, mucous or mucopurulent discharge from the lacrimal puncti, chronic conjunctivitis, and swelling of the lacrimal sac in the medial canthal area (acute or chronic dacryocystitis) are the symptoms that patients may experience due to nasolacrimal duct obstruction [1],[2].

The standard treatment of chronic dacryocystitis and epiphora is usually surgical, dacryocystorhinostomy (DCR). In principle DCR is the removal of the bone lying between the tear sac and the nose and making an anastomosis between medial wall of the sac and nasal mucosa. Despite good results obtained with traditional DCR, there are still different modifications added to the original technique. Such modifications include the passage of nasolacrimal tubings at the end of the operation [3], the closed nasolacrimal duct intubation [3],[4], the endoscopic DCR [5],[6],[7], and the laser-assisted DCR [8], the use of gauzes, suture materials, rubber or silicone catheters or tubings, absorbable gelatin sponges, polyethylene, and glass tubes placed in the bony ostium at the time of surgery to maintain the postoperative patency of the surgically created anastomosis and to improve the success rate of the DCR [9],[10],[11].

The aim of this study is to evaluate a novel modification which entails insertion of a permanent silastic stent that acts as a barrier against occlusion of the bony ostium and maintains a clear connection between the nose and lacrimal sac without performing anastomosis.


  Patients and methods Top


The cohort enrolled in this study included 28 patients (32 eyes) attending the clinics of the Research Institute of Ophthalmology (RIO), with the diagnosis of chronic dacryocystitis, failed previous DCR surgery, or chronic epiphora. Patients with canalicular obstruction were excluded from this study as well as children below the age of 3 years. Standard ophthalmic examination was performed together with preoperative ENT and systemic evaluation to prepare the patient for surgery. The patients were randomly selected for stent surgery irrespective to race, age, and sex. After obtaining approval from the ethics committee, explanation of the procedure, the foreseen advantages and the disadvantages of the new procedure was explained to all the patients, and an informed consent was taken from all of them.

The silicone tube used for manufacturing the stent [Figure 1] was fashioned from Alliedsil (Alliedsil™ Silicone Tubing- Permanently Implantable Tubing by Implantech Associates Inc-6025 Nicolle St # B, Ventura, CA, USA) silicone tubing a permanently implantable silicone tube. The tube material is nontoxic, odorless, tasteless, and inert, resists sticking and encrustation, thus will not support bacteria growth. It is nonreactive to body tissues and fluids, translucent providing visual contact with flow, soft, pliable, and contains no plasticizers which could leach out, causing flow contamination or tube hardening. Its thermal stability is (−100΀F to +500΀F) [12], so it is autoclavable and can also be sterilized by any other sterilization method.

The length of the stent varies from 16 to 20 mm that is also adjusted at the time of surgery; the medial end of the stent passes through the bony ostium and stops shortly before touching the nasal septum. The lateral end of the stent is placed within the lacrimal sac. The outer diameter of the stent is 6 mm and the inner lumen diameter is 4 mm. The stent has multiple openings 1.5 mm in diameter along the whole length of the stent that will act as extra drainage channels. The medial (nasal) end of the stent has four notches 2.5 mm in diameter, to assess the drainage of the tear, and guard against blockage of the medial end, if inadvertently in the postoperative period the stent is pushed or displaced medially touching the nasal septum or the surrounding tissues.

The procedure could be carried out with local or general anesthesia; however, all our cases were done under the effect of general anesthesia, as we felt being a new procedure it will be more convenient for the comfort of both the patient and the physician.

The technique used was essentially as that of standard DCR especially in its first part where the skin was incised, lacrimal sac located, and a bony ostium created in the nasal bone, in the lacrimal fossa [Figure 2] Then; a silastic stent is introduced and fitted in the created ostium [Figure 3] and [Figure 4].

For quick creation of the bony ostium, we designed three arrow head stainless steel surgical instruments (bone-puncturing instruments) [Figure 5] 4, 6 and 8 mm to create a near-round configuration osteotomy. Overall length of each instrument is 15 cm. They have a very sharp tip and sharp edges, acting as chisel to create and widen the osteotomy. The first one (the smallest) is 4 mm, used to initiate the osteotomy; simply by pushing it against the bone, rotating it both clockwise and anticlockwise while maintaining the forward pressure until the bone cracks and fragment. The second 6 mm and the third 8 mm in its widest diameter, the last two are used to widen the osteotomy. Thus the fashioned osteotomies are nearly of controlled fixed size to fit the medial (nasal-notched) end of the stent exactly so as to maintain the desired horizontal position [Figure 2].

The nasal mucosa covering the nasal side of the ostium was excised with scissors/scalpel. A metal probe was introduced in the nasal cavity in the side of the surgery and visualized through the osteotomy, assuring no mucosa covering the hole. Then a suction tube was introduced through the nasal cavity and left there till the end of the surgery. The medial wall of the lacrimal sac was excised. A lacrimal cannula was inserted through the upper and lower canaliculi to assure complete patency.

In the first few patients, vicryl 6/0 transfixation sutures were done, between the wall of the stent and the wall of the lacrimal sac and later after we got the experience we deferred this step as the stent was very nicely stabilized in the anatomical site and the only cases that were in need of transfixation were cases either the bone was inadvertently widened more than the tube diameter or recurrent cases with irregular osteotomies. In certain cases where the bone is so thick or in recurrent cases where osteotomy was performed in a previous surgery, bone rongeur was useful to smoothen and reshape the osteotomy. No special introducer was required for insertion, just holding the stent with toothed forceps and simply introduced it in the desired place so that the medial end passed through the osteotomy and the lateral (lacrimal) end is rested within the lacrimal sac [Figure 2]. If excess length of the stent was noticed it was trimmed to the desired length with a scalpel from the lateral (lacrimal) end. Flushing of the wound and stent with saline through lacrimal cannula was done in all cases till clear saline running freely through the stent into the nasal cavity was visualized.

The skin was closed in the usual way as in standard DCR. Oral antibiotics for 5 days, topical antibiotic and steroid eye drops were prescribed. Decongestive nasal drops/gel was installed in the nostril of the operated side three times daily for 1 week. The patients were encouraged to perform Valsalva's maneuver as early as the first day postoperatively and as frequent as three to four times per day especially in the first 10 days to ensure complete patency of the system and success of the surgery. Whenever the patient informed negative Valsalva - syringing was done to assure patency of the system. The follow-up of the patients was as follows; first day postoperatively, third day, weekly for 1 month, then monthly throughout the follow-up period. The patients were also referred to the otorhinologist at the third, sixth and ninth months, to examine the stent through the nose for patency, reaction or any unexpected finding [Figure 6].


  Results Top


This modification was applied to 32 eyes of 28 patients [Table 1]. They were eight males (10 eyes) and 20 females (22 eyes) [Figure 7] with a percentage of males (28.6%) to females (71.4%). The male to female ratio was 2 : 5. The age range was 19-61 with a mean of 38 years (΁13.07) [Figure 8]. They were 13 right and 19 left eyes, and four (12.5%) bilateral cases and 24 (87.5%) unilateral cases. Twenty-four eyes (75%) presented with epiphora, seven (21.8%) patients with swelling near the medial canthus (mucocele), and one (3.1%) patient with lacrimal fistula. Surgery was done to the 75% of the patients as primary procedure and in 25% of the patients as a secondary procedure [Figure 9]. All the patients were followed up in the following order - weekly for the first month, fortnightly for the second month, then monthly. The number of patients who completed the follow-up period were 20 (71.4%) and the number of drop outs were eight patients (28.6%).

The follow-up [Figure 10] ranged between 7 and 14 months with a mean of ΁9.5 months (΁2.04).The initial stent length used during surgery was 20 mm but the actual length used was 16.6 mm.

There were two successes and two failures taken in consideration; the first success was the 'surgical success' (the number of stents successfully inserted) and the second success was the 'overall success rate' (the success percentage calculated in this study) and it represents the percentage of the surgical success to cure the patient. 'Overall failure' was the number of failures due to persistence of the initial problem. The success rate [Figure 11] of this procedure was 96.9%, whereas 'overall failure' rate of the surgery was 3.1% [Figure 12]. 'Surgical failure' was the number of stents that failed to be inserted during surgery; this occurred only in one case. All the cases that were operated for the first time (24 eyes-primary cases), the surgical success rate was 100% while the only case with surgical failure was a patient reoperated for a previously failed DCR (one out of eight recurrent eyes (secondary cases).

The overall complication rate was 10.71%. Only three patients presented with complication in the posoperative period [Table 2]. One patient developed postoperative periorbital ecchymosis and the second patient developed postoperative epistaxis. Both patients were in the category of second procedure and they were hypertensive and diabetic and they were imporperly prepaired for surgery. Both complications were treated conservatively and no further intervention was considered. The third patient on nasal examination at ninth month,showed granulation tissue formation around the stent but valsalva maneuver was positive and syringing confirmed patency of the stent. Another finding that is worth mentioning was in our first case, the patient postoperatively was wondering about something palpable in the perinasal area (the stent was palpable subcutaneously), he was assured nothing was wrong and no further complaint afterwards. There was no single case of extrusion of the stent recorded.


  Discussion Top


External DCR is a highly successful procedure in managing epiphora and chronic dacryocystitis [13,14]. The reported success rate varies between 85 and 99% [15]. However, it is not technically easy, consists of multiphase procedure that entails considerable experience and long learning curve. Moreover, individual response to tissue healing process is also an important factor for the success of DCR surgery [14]. Failure in DCR surgery is primarily due to bony ostium occlusion with either membrane, synechiae or granulation tissue formation [16],[17],[18],[19],[20],[21],[22].

The success rate of this procedure was 96.9% that is similar to the success rate reported in other studies done by Pawar and Sutaria [23] Pawar and Patil [24] Lele et al. [25] Bhatt et al. [26] Pawar et al. [27] Reddy et al. [28] [Table 3] putting in consideration the number of patients and the follow-up period. Such high success rate, suggest that this modification could be used as a standard procedure and in theory could be an alternative to standard DCR.

The foreseen advantages of this modification to the standard DCR; it is less traumatizing to tissues due to less tissue manipulation and consequently reduced intra and postoperative bleeding as compared with conventional DCR. There is no predilection for age or sex. It is a reproducible surgery, with very short learning curve. The bony ostium patency is maintained without the need for anastomosis, because the stent acts as a conduit for the continuous flow of tears and a barrier against blockage of the ostium with membranes or granulation tissue.

Most of the inflamed thickened pathological lacrimal sac is excised during surgery containing all the pockets of pus and inflammatory reaction; the source of recurrent inflammation and the stent will be implanted in a clean field rather than intracystic - a potentially inflamed area, which is a major concern in the postoperative period and on the long run of the follow-up of the patient and recurrence of the condition. Thus; a major cause for the development of chronic dacryocystitis and epiphora is removed. Good cosmetic and esthetic results with 10-12 mm long skin incision which is enough for this procedure with no obvious postoperative scar are seen towards the end of third month. Early ambulation of the patient, the patient is discharged from hospital the same day of surgery. However few skinny patients wondered about a subcutaneous foreign body (FB) in the surgical area that was not present before the surgery.

In contrast to Pawar's intra-cystic stent, the length of the stent in Pawar's study varied from 12.0 to 15.0 mm, with an outer diameter of 2.5 to 3.0 mm [23].The average length our stent was 16.3 mm; this extra-length made it rest exactly in the lacrimal sac and the bony ostium and thus no extrusion was reported in our study. We also secured the tube with fixation sutures that helped to maintain and secure the position of the stent. Blockage of the stent was not reported in this study because the stent we used has more openings, than that used by Pawar, that acted as extra-channels for tears drainage and consequently obstruction of the stent is less likely to occur.

In contrast to conventional DCR less steps are required and consequently shorter time to complete the procedure with less tissue manipulation, less expected bleeding, consequently no need for postoperative nasal pack potentially applicable to all age groups including children. No reaction from the silicone stent was noted in this study and less hospitalization. Most patients were discharged the same day of the operation. As no anastomosis is done, the procedure is potentially applicable to all nasal problems such as nasal deformities and atrophic rhinitis.

Pawar used this procedure in children and advocated such procedure in children. The authors regarded at first that performing this procedure in children should be restricted and considered it an exclusion criterion. After performing several operations, the authors started to believe that this procedure could also be done in children with close watch over the stent which may dislodge; although not reported in this study, and become swallowed by the child causing him serious hazards. The advantages of this procedure in children; is that it allows the growth of the orbit and faces with near normal orbital anatomy; thus it allows for a more anatomical and successful second procedure; if needed.

The foreseen complications of this procedure lie in two categories; the first category is that pertaining to surgical procedure in this area, for example, DCR operation, and the second category pertaining directly to the stent; such complications occurred only in two patients (7.14%). The first category includes failure of the technique, recurrence of chronic dacryocystitis, wound problems, for example, visible scar, keloid formation and wound infection, postoperative cellulitis or nasal bleeding. This occurred only in two patients out of 28 patients with a percentage of 7.14%. The first patient developed cellulitis postoperatively and the second patient developed nasal bleeding postoperative. Both patients were among the second procedure group and they were also diabetic. Other complications were not reported in this study. The second category complications were namely difficulty of stent insertion, dislodgement of the stent, granulation tissue formation, late infection and loss of the stent. This was noticed in two patients (7.14%).The first was a case of difficult insertion of the stent, female patient included in secondary procedure group and the cause for this failure was a large previous osteotomy with surrounding loose and friable tissues that could not hold the transfixation sutures consequently the stent was not implanted; and the second was the development of granulation tissue around the stent, she was a female patient of the secondary procedure group and was easily managed by the ENT specialist. No other complications were reported in this study.


  Conclusion Top


After weighing matters we came to the conclusion that this procedure has several worthy advantages over the standard DCR, though not replacing as this will necessitate a longer study over years to follow-up the outcome of the procedure. It can be used as initial procedure and be an equally successful procedure for previously failed classic DCR surgery.


  Acknowledgements Top


Conflicts of interest

There are no conflicts of interest.

 
  References Top

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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11], [Figure 12]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

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