Journal of the Egyptian Ophthalmological Society

ORIGINAL ARTICLE
Year
: 2017  |  Volume : 110  |  Issue : 1  |  Page : 14--21

Study of the effect of different designs of nasal mucosal and lacrimal sac flaps on the success rate of external dacryocystorhinostomy


Ali M El Sawy, Momen M Hamdi, Sherif S Elwan, Tarek M Abdalla 
 Ophthalmology Department, Ain Shams University, Cairo, Egypt

Correspondence Address:
Momen M Hamdi
10 Hassan El Imam Street, Nasr City, 1st region , ZIP 11371, Cairo
Egypt

Abstract

Purpose The aim of this study was to assess the effect of the designing of four types of mucosal flaps on the success rates of dacryocystorhinostomy. Patients and methods In this prospective randomized study, dacryocystorhinostomy was performed for 128 eyes with nasolacrimal duct obstruction in adults complaining of epiphora. Patients were subdivided into four groups: group 1included 32 eyes in which only anterior flaps were sutured; group 2 included 32 eyes in which anterior flaps were sutured together with excision of posterior flaps; group 3 included 32 eyes in which anterior and posterior flaps were sutured; and group 4 included 32 eyes in which no flaps were created. Patients of all groups were followed up for 6 months. Assessment of operative success depended on subjective patient satisfaction − that is, stoppage or reduction in epiphora. Objective patency of fistula was assessed by means of positive syringing and estimating the area of the fistula using ultrasound. All data of four groups were statistically compared to assess significance. Results The success rate in group 1 was 100% in the first week, 100% after 1 month, and 93.8% after 6 months. The success rate in groups 2 and 3 was 100% in the first week, 100% after 1 month, and 96.8% after 6 months. There was no statistical significance for this disparity. The success rate in group 4 was 87.5% in the first week owing to fibrosis, 81.2% after 1 month, and 65.6% after 6 months. Using B-mode ultrasonography, the mean osteotomy area was 400mm2 intraoperatively for all cases, 337.4 mm2 (84.3% of intraoperative size) for the successful cases on the second postoperative day, and 32.2 mm2 (8% of intraoperative size) 6 months after the operation. Osteotomy size in unsuccessful cases was 237 mm2 (59.2% of intraoperative size) on the second postoperative day and 3.3 mm2 (0.8% of intraoperative size) 6 months after the operation. Conclusion Suturing of anterior suspended flaps in daryocystorhinostomies increases the success rate as in groups 1, 2, and 3. The difference between suturing, removing, or leaving the posterior flaps was found statistically nonsignificant. Thus, it can be judged intraoperatively according to its redundancy, ease of access, and operation time. It is not recommended to remove anterior and posterior flaps as this decreases the success rate significantly. The use of B-mode ultrasonography for follow-up of the osteotomy size postoperatively is recommended as a safe, effective, and noninvasive procedure.



How to cite this article:
El Sawy AM, Hamdi MM, Elwan SS, Abdalla TM. Study of the effect of different designs of nasal mucosal and lacrimal sac flaps on the success rate of external dacryocystorhinostomy.J Egypt Ophthalmol Soc 2017;110:14-21


How to cite this URL:
El Sawy AM, Hamdi MM, Elwan SS, Abdalla TM. Study of the effect of different designs of nasal mucosal and lacrimal sac flaps on the success rate of external dacryocystorhinostomy. J Egypt Ophthalmol Soc [serial online] 2017 [cited 2017 Jun 25 ];110:14-21
Available from: http://www.jeos.eg.net/text.asp?2017/110/1/14/206312


Full Text



 Introduction



Primary acquired nasolacrimal duct (NLD) obstruction is an idiopathic condition. Pathological studies of the nasolacrimal passage have indicated that it is caused by fibrous obstruction secondary to chronic inflammation [1]. Obstruction of the NLD results in disturbed outflow of the tears, commonly known as ‘epiphora’ [1].

The most popular operation performed for NLD obstruction is external dacryocystorhinostomy (DCR). It is a drainage procedure designed to bypass the site of NLD obstruction by forming a fistula between the lacrimal sac and the nasal cavity [2]. It can be performed using either the external approach, the endonasal approach, or the transcanalicular approach [3].

Over the years, modifications varied from creating anterior and posterior sac and nasal mucosal flaps and anastomosing them, to make very large, mobile anterior flaps of the sac and nasal mucosa. Excision of the posterior sac mucosa may improve the success rate of external DCR but the clinically significant difference was found to be statistically nonsignificant [4].

The placement of posterior flap sutures is not universally undertaken. Their insertion, however, controls hemorrhage from that source; the mucosa-to-mucosa anastomosis precludes the development of granulation tissue with its possible attendant infection and secondary hemorrhage, and the fixation of the tissues in their desired position obviates the chance adhesion between the anterior and posterior flaps as mentioned by Collin [5].

 Patients and methods



This is a prospective randomized study. A total of128 eyes were recruited from the outpatient clinic of the Department of Ophthalmology in Ain Shams University between December 2009 and October 2010.

This study adheres to the tenets of the Declaration of Helsinki and was approved by the ethical committee of Ain Shams University. Informed written consent was obtained from all patients.

All cases were operated by a single senior professor (the third author) in the department using the same technique.

Patients were subdivided into four groups of 32 eyes each:Group 1 included eyes in which only anterior flaps were sutured.Group 2 included eyes in which anterior flaps were sutured together with excision of posterior flaps.Group 3 included eyes in which anterior and posterior flaps were sutured.Group 4 included eyes in which no flaps were created.

All patients were followed up for 6 months.

Patients with canalicular or common canalicular blockade, noticeable lid laxity, or previous lacrimal surgery were excluded from the study. Suspicion of malignancy, radiation therapy, tuberculous or atrophic rhinitis, post-traumatic lids, and bony deformity were also considered in the exclusion criteria. Patients younger than 15 years, with previous ocular surgical treatment, uncontrolled ocular inflammation, or other ocular or systemic diseases (e.g. bleeding tendency) were also excluded.

The criteria for operative success were subjective patient satisfaction with stoppage or reduction in epiphora, in addition to objective patency of fistula assessed by means of positive syringing and by estimating area of fistula using ultrasound.

Statistical comparison of the results of the four groups was then made.

Surgical technique of dacryocystorhinostomy

A skin incision was made medial to the angular vessels at the level of the medial canthal tendon (MCT) extending downwards and laterally. Blunt dissection of the orbicularis fibers was performed. After dividing the superficial part of the MCT, the periosteum was incised anterior to the anterior lacrimal crest and reflected laterally with the sac to expose the lacrimal bony fossa.

A 20×20 mm osteotomy was performed extending from the posterior lacrimal crest to 5 mm anterior to the anterior lacrimal crest and from the reflected portion of the MCT to the inferior orbital rim.

The medial wall of the sac was vertically incised using Wescott’s scissors assisted by a Bowman’s probe.

Anterior flaps only were created in groups 1 and 2, and hence the incision was made more posteriorly to make larger anterior flaps and leave small posterior flaps, which were cut in group 2. Posterior flaps only were created in group 3, and hence the incision was made midway to make anterior flaps and leave posterior flaps equal in size to be sutured. Both flaps were cut in group 4. Silicone intubation was performed in all cases.

The posterior flaps of the lacrimal sac and nasal mucosa were sutured edge to edge under the tubes with 6/0 polyglactin sutures in group 3 and cut in groups 2 and 4. The anterior flaps of the lacrimal sac and nasal mucosa were sutured edge to edge over the tubes using 6/0 polyglactin sutures in groups 1, 2, and 3 and cut in group 4; the lacrimal retractors were removed and interrupted 6/0 polyglactin sutures were used to reapproximate the orbicularis muscle.

The skin incision was closed using 6/0 silk interrupted sutures. Bandage was applied to the skin incision.

First week postoperative treatment included oral antibiotics, topical combined antibiotic–steroid eye drops, antibiotic ointment over the incision site, and nasal decongestant gel and drops. Sutures were removed 5–7 days later. B-mode ultrasonography was performed on the osteotomy site to assess its size. Silicone tube was cut and removed 3 months later.

All patients were followed up at 1 week (skin sutures were removed), 2 weeks, 3 months (silicone tube was removed), and then monthly for 6 months.

During each visit, subjective relief of symptoms (epiphora and discharge) was assessed. Assessment of the patency of lacrimal system was carried out using the regurgitation test, dye disappearance test (DDT), and syringing if the patient showed delayed DDT. Stability of the silicone tube and healing of the skin wound were also inspected.

B-mode ultrasonography was performed on the second postoperative day, at 1 week, 3 months, and 6 months postoperatively to evaluate the lacrimal sac dimensions as well as the position and size of the ostium created. The vertical and horizontal dimensions were measured using OTI-Scan 3000 A/B-scan system (Optos, Marlborough , MA, USA) with a 10 MHz vector probe, with a 30 scans/sec refreshment rate. A coupling gel was applied to the wound area during the procedure. Patients were examined in a semierect position. The probe was oriented vertically and swept horizontally, and the maximum dimension was taken. Cursor fixation was performed and dimensions were photographed as still photographs as shown in [Figure 1] and [Figure 2].{Figure 1}{Figure 2}

Bone and soft tissue appear white in sonograms as they have high reflectivity, and thus are highly echogenic. Cavities, either air filled or fluid filled, have low reflectivity and thus appear dark. The interface between the soft tissue and the bone in a DCR fistula is practically extremely difficult to elicit in sonograms, and thus the soft tissue fistula dimensions were taken as rough measurements of the osteotomy area.

 Results



A total of 16 (12.6%) patients were male and 110 (87.3%) were female. Two (1.5%) cases were bilateral, 61 (47.6%) were on the right side, and 67 (52.3%) were on the left side. Their ages ranged from 29 to 72 years and the mean age was 48.1 years.

Statistical methods used in the analysis of results were as follows: Student’s t-test, the Pearson χ2-test, and Fisher’s exact test.

A total of 112 patients presented with chronic dacryocystitis and 16 had lacrimal mucoceles. The regurge test was positive in 112 (87.5%) cases and negative in 16 (12.5%) cases. Syringing revealed total obstruction in all 128 cases, and the DDT was positive in all 128 cases. [Table 1] shows sex distribution and presentation within the four study groups.{Table 1}

Results during the follow-up period are described in [Figure 3].{Figure 3}

Mild postoperative epistaxis occurred in 16 (20%) cases as distributed over the four groups. It occurred in the first few hours, but it was self-limited with no need for nasal pack. [Table 2] describes the postoperative complications in the four groups.{Table 2}

Osteotomy size evaluation

The mean osteotomy area was 400 mm2 intraoperatively for all cases. On the second postoperative day, it was 337.4 mm2 (84.3% of intraoperative size) for the successful cases (113 cases; 88.2%); this is based on the ultrasound in which the mucous membrane edge make the ostium smaller. At the end of the study period 6 months postoperatively, the same osteotomy became 32.2 mm2 (8% of intraoperative size(owing to fibrosis.

As regards unsuccessful cases (15 cases; 11.7%) osteotomy size was 237 mm2 (59.2% of intraoperative size) on the second postoperative day. At end of the study period 6 months postoperatively, it was reduced to 3.3 mm2 (0.8% of intraoperative size). [Figure 4],[Figure 5],[Figure 6],[Figure 7],[Figure 8],[Figure 9],[Figure 10] describe the different ultrasonic pictures throughout the follow-up period in this work.{Figure 4}{Figure 5}{Figure 6}{Figure 7}{Figure 8}{Figure 9}{Figure 10}

The surgical outcome and success rate during the follow-up period in the study are described in [Table 3].{Table 3}

A case was considered occluded once subjectively epiphora recurred, and/or any two of the following was found: positive DDT, positive reflux, or syringing ([Figure 3]).

The success rates of four groups and P-value of significance are described in [Table 4].{Table 4}

On comparing the results, groups 1, 2, and 3 showed that the difference in success rates is not statistically significant (P<0.05, χ2-test, [Table 4]). However, when the success rates of groups 1, 2, and 3 were compared with that of group 4, the difference was statistically significant (P<0.05, χ2-test) ([Table 4]).

 Discussion



External DCR with only anterior flaps is probably the most common variant among surgeons, owing to the simplicity and shorter operating time. Mobile nasal mucosal and sac flaps are liable to adhere to underlying tissues, thus increasing the possibility of closure of a recently formed lacrimal passage. Although excision of the posterior sac flap in this context has been reported to improve the success rate of external DCR, this difference could not show statistical significance. This improvement in success rate was attributed to excising a portion of the wall of an atonic sac, thus avoiding a potential reservoir effect that may impede drainage. The technique of suturing both anterior and posterior flaps probably decreases the possibility of primary bleeding and reduces the tendency toward secondary hemorrhage. The technique of excising the posterior sac flap has a comparable effect, and is a technically simpler one [6].

Only a few studies have examined the difference in outcomes in relation to the technique of designing mucosal anastomosis [6],[7],[8],[9]. None of these studies has shown any statistical difference among the different patterns of flaps created, including no flap suturing at all [8].

In the present study, we were able to demonstrate that designing of a flap, whether to be anterior only, posterior, or both, has an improving impact on the success rate of external DCR over creating an osteotomy without mucosal flaps at all. Our explanation is that mucosal flaps drape the osteotomy edge, giving a mechanical barrier, and probably a biological one as well, ahead of growing osteoblasts that prevent further closure of the osteotomy. This concept is further proved by findings of ultrasonographic imaging of the osteotomy size. The mean osteotomy area was 400 mm2 intraoperatively for all cases. This became 32.2 mm2 SD=±4 (8% of intraoperative size) in all cases with flaps, versus 3.3 mm2 SD=±3 (0.8% of intraoperative size) for cases without flaps in group 4 at the end of 6-month follow-up period. This difference in osteotomy size was found highly statistically significant (χ2>0.01).

Utilization of ultrasound in the assessment of lacrimal drainage system anatomy and disease has been well documented [10]. Ultrasonography is a simple technique that causes minimal or no discomfort to the patient. Intranasal endoscopy is difficult to perform in the first few postoperative days due to intranasal hematoma and tissue tenderness, and may cause some discomfort to patients with narrow anterior nares. Applying and sweeping the probe over the area of the wound causes pain on the first 2 postoperative days [11].

Although we used a higher frequency (10 MHz) than that used by other investigators (7 MHz) [10], the interface between the soft tissue and bone was practically impossible to elicit all through. The measurements taken were thus the dimensions of the soft tissue ostium, which correlated well with the clinical function of the fistula and objective assessment such as improvement in tearing and negative regurge test. The 60% reduction in the intraoperative osteotomy size on the third postoperative day related both to the size of the soft tissue and the reduction in tissue edema. However, a subsequent reduction is only attributable to healing either by fibrosis or by bone relay [12].

Our ultrasonography results conform with those obtained by other investigators utilizing intranasal endoscopy [11]. However, the results of both studies indicate that most of the fistula area reduction occurs in the first postoperative week owing to potential fibrosis. Our results show that a fistula area as small as 17 mm2 was fully functional. B-mode ultrasonography showed a marked reduction in fistula area at 6 months postoperatively, and thus we recommend that the bony ostium should be made as large as the anatomical structure allows.

 Conclusion



Suturing of anterior suspended flaps increases the success rate as in groups 1, 2, and 3. The difference between suturing, cutting, or leaving the posterior flaps was statistically nonsignificant. Thus, it can be judged intraoperatively according to its redundancy, ease of access, and operation time. It is not recommended to cut anterior and posterior flaps as this decreases the success rate significantly.

The use of B-mode ultrasonography for follow-up of the osteotomy size postoperatively is recommended as a safe, simple, effective, and noninvasive procedure.

Financial support and sponsorship

Nil.

Conflicts of interest

There is no conflicts of interest.

References

1Linberg JV, McCormick SA. Primary acquired nasolacrimal duct obstruction. A clinical pathologic report and biopsy technique. Ophthalmology 1986; 93:1055–1063.
2Tanenbaum M, McCord CD. The lacrimal drainage system. Chapter 13. In: Tasman Wand Jaeger E, editor. Duane’s clinical ophthalmology. 4. Philadelphia: Lippincott Co.; 1998. pp. 1–25.
3Eloy P, Bertrand B, Martinez M, Hoebeke M, Watelet JB, Jamart J. Endonasal dacryocystorhinostomy: indication, technique and resuits. Rhinology 1995; 33:229–233.
4Chritopher J, Qunin OD. Treating epiphora in adults. In: Sowka JW, Gurwood AS, Kabat AG, editors. Hand book of ocular disease management. Review of Optometry. 1998. p. 15.
5Collin JRO, editor. A manual of systematic eyelid surgery. 3rd ed. London, UK: Butterworth-Heinemann, Elsevier Health Sciences; 2006; 8:pp. 165–176.
6Elwan S. A randomized study comparing DCR with and without excision of the posterior mucosal flap. Orbit 2003; 22:7–13.
7Baldeschi L, Nardi M, Hintschich CR, Koornneef L. Anterior suspended flaps: a modified approach for external dacryocystorhinostomy. Br J Ophthalmol 1998; 82:790–792.
8Pandya VR, Lee S, Benger R, Danks JJ, Kourt G, Martin PA et al. The role of mucosal flaps in external dacryocystorhinostomy. Orbit 2010; 29:324–327.
9Yazici B, Yazici Z. Final nasolacrimal ostium after external dacryocystorhinostomy. Arch Ophthalmol 2003; 121:76–80.
10Ezra E, Restori M, Mannor GE, Rose GE. Ultrasonic assessment of rhinostomy size following external dacryocystorhinostomy. Br J Ophthalmol 1998; 82:786–789.
11Linberg JV, Anderson RL, Bumsted RM, Barreras R. Study of intranasal ostium external dacryocystorhinostomy. Arch Ophthalmol 1982; 100:1758–1762.
12Elwan S, Hamid MA, Sharaf M. Ultrasonographic assessment of fistula size in DCR. Bul Ophthalmol Soc Egypt 2003; 96:827–829.