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ORIGINAL ARTICLE
Year : 2022  |  Volume : 29  |  Issue : 1  |  Page : 1-6  

External versus endoscopic dacryocystorhinostomy for primary acquired nasolacrimal duct obstruction


1 Department of Ophthalmology, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
2 Department of Eye, Eye Research Center, School of Medicine, Amiralmomenin Hospital, Guilan University of Medical Sciences, Rasht, Iran
3 Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran
4 ENT and Head and Neck Research Center, The Five Senses Institute, Iran University of Medical Sciences, Tehran, Iran
5 Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Date of Submission16-Aug-2021
Date of Acceptance09-May-2022
Date of Web Publication23-Nov-2022

Correspondence Address:
Prof. S Saeed Mohammadi
Department of Ophthalmology, Farabi Eye Hospital, Tehran University of Medical Sciences; Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran
Iran
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/meajo.meajo_238_21

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   Abstract 


PURPOSE: The purpose of the study is to compare the surgical outcomes and success rates of external dacryocystorhinostomy (EX-DCR) versus endoscopic endonasal DCR (EN-DCR) for the treatment of primary acquired nasolacrimal duct obstruction (PANDO).
METHODS: This retrospective nonrandomized study was conducted at Farabi Eye Hospital and Noor Eye Hospital, Iran. A review of electronic medical records of all patients with PANDO who underwent EX-DCR or EN-DCR between January 2016 and 2018 was carried out.
RESULTS: A total of 803 patients underwent surgery, of which 618 patients (77%) were managed by EX-DCR and 185 patients (23%) by EN-DCR. The majority of cases (62%) were female. The mean age of the patients in EX-DCR and EN-DCR groups was 40.8 ± 14.2 and 34.3 ± 9.2 years, respectively. EX-DCR resulted in significantly less amount of pain compared to EN-DCR (P < 0.05). The success rate of surgery among EX-DCR and EN-DCR groups was 92.4% and 91.1%, respectively, and did not show statistically significant difference. A higher incidence of intraoperative hemorrhage requiring intervention was noted in the EN-DCR group (16.7% vs. 4.5%). Postoperative patient's satisfaction with EN-DCR and EX-DCR was 73% and 82%, respectively.
CONCLUSION: Both EX-DXR and endoscopic DCR surgeries have high success rates and low incidence of failure. The choice of DCR technique should be based on the experience of the surgeon and patient's lacrimal and nasal anatomy and preferences.

Keywords: Endoscopic endonasal dacryocystorhinostomy, external dacryocystorhinostomy, primary nasolacrimal duct obstruction


How to cite this article:
Rajabi MT, Shahraki K, Mohammadi S S, Nozare A, Moravej Z, Tavakolizadeh S, Salim RE, Hosseinzadeh F, Mohammadi S, Farahi A, Shahraki K. External versus endoscopic dacryocystorhinostomy for primary acquired nasolacrimal duct obstruction. Middle East Afr J Ophthalmol 2022;29:1-6

How to cite this URL:
Rajabi MT, Shahraki K, Mohammadi S S, Nozare A, Moravej Z, Tavakolizadeh S, Salim RE, Hosseinzadeh F, Mohammadi S, Farahi A, Shahraki K. External versus endoscopic dacryocystorhinostomy for primary acquired nasolacrimal duct obstruction. Middle East Afr J Ophthalmol [serial online] 2022 [cited 2022 Nov 26];29:1-6. Available from: http://www.meajo.org/text.asp?2022/29/1/1/361873




   Introduction Top


Primary acquired nasolacrimal duct obstruction (PANDO) is a common condition that usually manifests as epiphora and dacryocystitis. Dacryocystorhinostomy (DCR) is the standard surgical procedure for the treatment of PANDO. There are two main DCR techniques. The gold standard treatment for nasolacrimal duct obstruction (NLDO) is the transcutaneous DCR or external DCR (EX-DCR).[1] EX-DCR, first described by Toti,[2] is performed by a skin incision above the lacrimal sac. Following the introduction of the nasal endoscope, various methods of endoscopic DCR, from mechanical to laser-assisted lacrimal surgeries, have been developed.[3],[4] Several reports have shown the success rate of external and endoscopic DCR ranging from 70% to 99%.[5],[6],[7],[8],[9] EX-DCR has some advantages including better evaluation of the lacrimal sac, wide surgical field, and better visualization of the flap and suturing.[10] On the other hand, endoscopic DCR is less invasive with no disruption of eyelid's anatomy, no risk of skin scar, and possible shorter operation time.[11] The disadvantages of endoscopic DCR include smaller opening between the lacrimal sac and nasal cavity, difficulty of suturing and manipulation of the lacrimal sac and nasal mucosal flaps, high equipment cost, and acquiring endoscopic skills for ophthalmologists.

The purpose of this study is to compare the surgical outcomes and success rates of EX-DCR and endoscopic DCR for the treatment of PANDO in patients referring to tertiary referral centers, Farabi and Noor Eye Hospitals, Tehran, Iran.


   Methods Top


This retrospective, nonrandomized study was conducted at Farabi and Noor Eye Hospitals, Tehran, Iran. A total of 803 patients with PANDO who underwent EX-DCR or endoscopic endonasal DCR (EN-DCR) between January 2016 and 2018 were enrolled in this study.

Patients with a history of tearing or dacryocystitis underwent a complete ophthalmic examination including inspection, palpation of the lacrimal sac, slit-lamp examination, fluorescein dye disappearance test, syringing and probing along with irrigation of the nasolacrimal drainage system, and nasal cavity examination.

Inclusion criteria were patients confirmed to have only NLDO with probing and irrigation test. Exclusion criteria were previous lacrimal surgery, previous mid-face trauma, punctual anomalies, canalicular obstruction, lower eyelid malposition, nasal pathology, and unsuitability for local or general anesthesia. EX-DCR or endoscopic DCR was performed according to the patients' preference.

All patients were informed of both the surgical procedures and their benefits and limitations. Informed written consent was obtained from all the patients before the procedure. Ethical clearance was obtained from the Ethical Committee of Tehran University of Medical Sciences. This study was approved by the Institutional Review Board of Tehran University of Medical Sciences and was conducted in adherence with the tenets of the Declaration of Helsinki.

Surgical technique

Anesthesia type (i.e., general or local) for either surgery was selected based on the preoperative anesthesiology consultation. EX-DCR surgeries were performed by ophthalmology residents under the guidance of a single attending oculofacial plastic surgeon (MT.R). All endoscopic endonasal surgeries were performed by an experienced oculofacial plastic surgeon (MT.R). An otolaryngologist specialist was also present for any guidance needed when performing EN-DCR.

For EX-DCR, a 1–2 cm area anterior to the middle turbinate on the lateral nasal wall was infiltrated with lidocaine 2% and epinephrine (1:200,000). After a straight 10–12 mm skin incision, blunt dissection between skin and orbicularis muscle was performed. The periosteum was incised and elevated. Osteotomy was made in front of the lacrimal sac. After opening the lacrimal sac, silicone tube was placed depending on the case and surgeons' judgment. Finally, the mucosa was incised, and nasal flaps were created in the usual manner. Anastomosis was also performed as the final step. Wound closure was then performed adequately.

For EN-DCR, a mixture of lidocaine (2%) and epinephrine (1:200,000) was injected into the middle meatus and middle turbinate mucosa. If local anesthesia was chosen, an injection was also administered from the skin side in the medial canthus.

A mesh soaked in lidocaine ointment and phenylephrine (0.5%) drops was then placed in the nasal cavity for 15 min. If septoplasty was planned, the ENT surgeon performed it before DCR.

A monitor screen was connected to the administered rigid nasal fibrotic endoscope. A periosteal elevator was used to form the primary mucosal incision along the maxillary line in front of the middle turbinate attachment. Polyp shaver was administered to excise the nasal mucosa to reach behind the posterior crest of the lacrimal bone. Sinus surgery and the removal of agger nasi cells or concha bullosa were performed, if required. The lacrimal bone in front of the lacrimal sac fundus was removed with a Kierson or a Medtronic drill (Medtronic, Novi, MI, USA) if required, and the medial wall of the lacrimal sac was entirely excised. Lacrimal probe was passed through both upper and lower canaliculi to determine the precise location of the new ostium. The surgeon carefully produced adequate space in front of the new osteotomy position.

Silicone tubes were passed through both upper and lower canaliculi and fixed with multiple intranasal knots. In all patients, a mesh soaked in lidocaine, erythromycin, and betamethasone was placed in the nasal cavity. The mesh was removed after 1 day. Intranasal irrigation with normal saline solution was performed and intranasal corticosteroid spray was prescribed.

At every follow-up visit, irrigation with normal saline solution was performed, even with the silicone tube in place.

All patients of both surgeries were advised to use cold compress for 48 h after the surgery and to instill chloramphenicol (Chlobiotic 0.5% ophthalmic drop, Sina Darou, Tehran, Iran) and betamethasone (Betasonate 0.1% ophthalmic drops, Sina Darou, Tehran, Iran) in the eye of the operated side every 6 h for 1 week. The patients also received cephalexin 500 mg four times daily for 5 days.

During the follow-up visits, patients were asked about the symptom relief of epiphora. Fluorescein dye disappearance test and nasolacrimal systems irrigation were performed for all patients. Surgical time and intraoperative or postoperative complications, such as hemorrhage requiring intervention, skin scar, and infection, were recorded. The skin sutures of the patients with EX-DCR were removed 1 week postoperatively. All patients were assessed at the 1st week, 1st month, and 2nd month postoperatively. Periodic intranasal examinations were also scheduled at the same intervals. The silicone tube was removed after 8–10 weeks, postoperation. All patients were followed up every 2 months for 6 months after the surgery.

The surgery was deemed as successful if patient's symptoms such as tearing resolved at the final visit and patency were confirmed on irrigation and a positive fluorescein dye disappearance. Inability to irrigate the lacrimal system postoperatively, scarring at the intranasal osteotomy, and/or no visualization of fluorescein dye was classified as a surgical failure. Patients were also categorized as a surgical failure if they experienced any postoperative episode of dacryocystitis or tearing symptoms. Statistical analysis was carried out using IBM SPSS Statistics for Windows software (version 22, IBM Corp. Armonk, NY, USA). Independent-samples t-test was used to compare differences in numerical variables between groups, whereas nonparametric Chi-square analysis was used to compare proportions between groups. P < 0.05 was considered statistically significant.


   Results Top


A total of 803 patients were included in the study, of which 618 (77%) were managed by EX-DCR and 185 (23%) by EN-DCR.

The demographics of the study population are summarized in [Table 1]. Overall, 498 of the NLDO patients (62%) were female.
Table 1: Demographics of patients undergoing external dacryocystorhinostomy versus endoscopic dacryocystorhinostomy

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[Table 2] demonstrates the surgical outcomes in patients undergoing EX-DCR and endoscopic DCR. The comparative overall success rate between the endonasal DCR and EX-DCR groups was not statistically significant (92.44% vs. 91.1%, P = 0.64). Fifty-five patients (8.9%) of EX-DCR showed symptoms of failure, while 14 cases (7.56%) in EN-DCR group showed failure symptoms. Respectively, in the EN-DCR and EX-DCR groups, 92.9% and 75.8% of the failure cases were male patients. There was a significant difference between male and female patients in terms of DCR failure (Chi-square test, P < 0.001).
Table 2: Comparison of surgery outcome in patients undergoing external dacryocystorhinostomy (primary and secondary) and endoscopic dacryocystorhinostomy

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Intraoperative hemorrhage (more than 20 cc hemorrhage) was found to be the most frequent problem encountered during surgery. A higher incidence of intraoperative hemorrhage requiring intervention was noted in the EN-DCR group (16.7%) in comparison to EX-DCR group (4.5%), which was statistically significant (Chi-square test, P < 0.001).

Postoperative pain was compared in the surgical groups in the first postoperative visit. EX-DCR resulted in significantly less amount of pain compared to EN-DCR (P < 0.05). Overall male patients were more likely to report no pain (63.3%), and female patients were more likely to report mild pain (58.4%) after surgery. Furthermore, 72.9% of female and 36.7% of male patients experienced some grade of pain postoperatively (data not shown).

Of the total 803 patients undergoing DCR, 161 patients (111 from the EX-DCR group and 50 from the EN-DCR group) were unsatisfied with the procedure of which all patients were female. Postoperative satisfaction of EN-DCR and EX-DCR was 73% and 82%, respectively. In the external approach, skin incision scar was invisible in 39.5% (242) of patients, 42.24% (261) had a fine line at operation site, and 15.54% (96) of patients had a visible line with mild elevation. Nineteen patients (3.07%) had a visible hypertrophic scar and were unhappy about the cosmetic result.

No cases of cerebrospinal fluid leak, orbital tissue damage, or uncontrolled bleeding occurred.


   Discussion Top


Congenital and acquired NLDO are common diseases in children and adults. Nasolacrimal probing is indicated in congenital cases with high success rates in membranous obstruction.[12] EX-DCR is the standard approach in the treatment of acquired NLDO which allows direct view of the surgical area to acquire an epithelialized DCR pathway. In this procedure, lacrimal sac biopsy can be performed in cases of an abnormal sac during surgery. In various literature, the success rate of primary EX-DCR ranges between 70% and 96%,[13] and our results indicated 91.1% success rate similar to these values.

Endoscopic DCR became popular in the 1990s and eliminated the need for skin incisions, resulting in cosmetic convenience and less interference with the medial canthal tendon and lacrimal pump mechanism.[3],[4] During endoscopic DCR, nasal and paranasal sinus abnormalities including septal deviation, sinus disease, and turbinate hypertrophy can be identified and managed accordingly.[14] The success rate for this procedure has been reported to be 58%–93%.[13] In the present study, we achieved 92.44% success rate for endonasal DCR patients.

When comparing the success rate of these two procedures, we did not find any significant difference. Specific instruments, technical difficulties, and longer operative durations have however limited the application of endoscopic DCR. Furthermore, the steeper learning curve for endoscopy procedures should be considered. In our study, an ophthalmologist performed the EN-DCR and an otolaryngologist specialist was present for assistance. Considering that the EX-DCR surgeries were performed by ophthalmology residents under the attending ophthalmologist's guidance, a reasonable success rate was noted in this group compared to endoscopic DCR. This matter indicates the low learning curve for EX-DCR surgery and acceptable outcomes. Some previous studies have shown EX-DCR to be more successful.[15],[16] On the other hand, several studies have found higher success rates in endoscopic DCR.[5],[8],[11],[17] Many other comparative studies indicated comparable results in the two techniques.[18],[19],[20],[21],[22] A recent review by the American Academy of Ophthalmology reported that the endonasal approach using laser has worse outcomes than EX-DCR.[13] The results in the literature have indicated relatively superior results in the external approach, presumably due to the smaller rhinostomy performed by surgeons in the endoscopic approach and good anatomic identification of the sac and mucosal lining.

The large number of NLDO cases undergoing DCR in the present study adds value to our results, and therefore, it is safe to presume fairly equivalent success rates in EX-DCR and endoscopic DCR. The authors believe that a successful DCR regardless of the approach depends on various surgeon- and patient-related factors.

No major intraoperative and postoperative complications were observed in our study. Intraoperative bleeding occurred in 16.7% of endoscopic DCRs and 4.5% of the EX-DCR. The difference in intraoperative bleeding between the two groups was statistically significant and higher in endoscopic DCR. In previously published literature, lower rates of intraoperative bleeding were observed in the endoscopic (5.5%[6] and 6.5%[20]) and higher rates in the external (18%[18] and 4.6%[6],[20]) approach. This may be due to patient-related factors that were not regarded in our study or surgeon-related factors since endoscopy was carried out by an ophthalmologist who is less familiar with intranasal anatomy than an otolaryngologist specialist. Unlike other studies,[23] surprisingly, in our study, endoscopic patients endured more pain on the first postoperative visit.

Regarding scar formation and skin healing in patients managed with EX-DCR, 242 (39.5%) and 261 (42.24%) patients had an invisible and a fine line at the incision site, respectively. Devoto et al. reported that 6 months after surgery, the scar was invisible in 44% of the patients, a minimal scar remained in 47% of patients, and a moderate scar remained in 9% of patients.[24] Nineteen patients (3.07%) in our study had a visible hypertrophic scar at the surgery site and were unhappy about the cosmetic result, which was much lower than the rates reported in a meta-analysis of 554 EX-DCRs (10.8%).[25]

In our study, 161 (20%) patients were unsatisfied with the surgery of which all were female. This may be attributable to the short follow-up time of the study and the longer follow-up may have yielded higher satisfaction rates. Ozer and Ozer reported that the ratio of patients unhappy with the cosmetic results was higher in the EX-DCR group in the first postoperative week, but 1 year postoperatively, the ratio was similar in both EX-DCR and EN-DCR groups.[23] A review of the cosmetic significance of EX-DCR scars reported that younger age and female sex were risk factors for postoperative complaints of visible scars.[7] It is therefore suggested that younger patients and those with probable scarring due to anatomical factors should be managed from the endonasal approach.

The limitations of our study included the retrospective design and the short follow-up time. In addition, surgery was performed by different surgeons and there was no standard osteotomy size in either the endoscopic or external approach. Although the results of the current study suggest that both techniques seem equally acceptable surgical options for the management of NLDO, future prospective, randomized, and patient-matched studies are able to accurately evaluate the differences. Owing to different study designs, inclusion criteria, and outcome measures in studies, it is difficult to make a definite evidence-based determination about the relative efficacies of endonasal and EX-DCR. Due to advances in technology in the past decade, the differences in outcomes between the two techniques have been reduced.


   Conclusion Top


We conclude that both EX-DCR and endoscopic DCR surgeries have relatively equal success rates with low incidence of adverse events and high patient satisfaction. The choice of DCR technique should be based on the experience of the surgeon, available resources, patient's lacrimal and nasal anatomy, and preferences.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the Tehran University of Medical Sciences and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Materials: All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers' bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements) or nonfinancial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript.

Informed consent

The nature of the study was explained to all participants in simple language and informed consent was obtained from all individual participants included in the study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
   References Top

1.
Savino G, Battendieri R, Traina S, Corbo G, D'Amico G, Gari M, et al. External vs. endonasal dacryocystorhinostomy: Has the current view changed? Acta Otorhinolaryngol Ital 2014;34:29-35.  Back to cited text no. 1
    
2.
Toti A. Nuovo metodo conservatore di cura radicale delle soppurazioni croniche del sacco lacrimale (dacriocistorinostomia) Clínica Moderna (Firenze) 1904;10:385-7.  Back to cited text no. 2
    
3.
Caldwell G. Two new operations for obstruction of the nasal duct, with preservation of the canaliculi. Am J Ophthalmol 1893;10:189-92.  Back to cited text no. 3
    
4.
Metson R, Woog JJ, Puliafito CA. Endoscopic laser dacryocystorhinostomy. Laryngoscope 1994;104:269-74.  Back to cited text no. 4
    
5.
David S, Raju R, Job A, Richard J. A comparative study of external and endoscopic endonasal dacryocystorhinostomy – A preliminary report. Indian J Otolaryngol Head Neck Surg 1999;52:37-9.  Back to cited text no. 5
    
6.
Dolman PJ. Comparison of external dacryocystorhinostomy with nonlaser endonasal dacryocystorhinostomy. Ophthalmology 2003;110:78-84.  Back to cited text no. 6
    
7.
Sharma V, Martin PA, Benger R, Kourt G, Danks JJ, Deckel Y, et al. Evaluation of the cosmetic significance of external dacryocystorhinostomy scars. Am J Ophthalmol 2005;140:359-62.  Back to cited text no. 7
    
8.
Ben Simon GJ, Joseph J, Lee S, Schwarcz RM, McCann JD, Goldberg RA. External versus endoscopic dacryocystorhinostomy for acquired nasolacrimal duct obstruction in a tertiary referral center. Ophthalmology 2005;112:1463-8.  Back to cited text no. 8
    
9.
Tsirbas A, Davis G, Wormald PJ. Mechanical endonasal dacryocystorhinostomy versus external dacryocystorhinostomy. Ophthalmic Plast Reconstr Surg 2004;20:50-6.  Back to cited text no. 9
    
10.
Eichhorn K, Harrison AR. External vs. endonasal dacryocystorhinostomy: Six of one, a half dozen of the other? Curr Opin Ophthalmol 2010;21:396-403.  Back to cited text no. 10
    
11.
Woog JJ, Kennedy RH, Custer PL, Kaltreider SA, Meyer DR, Camara JG. Endonasal dacryocystorhinostomy: A report by the American Academy of Ophthalmology. Ophthalmology 2001;108:2369-77.  Back to cited text no. 11
    
12.
Medghalchi A, Mohammadi MJ, Soltani Moghadam R, Dalili H. Results of nasolacrimal duct probing in children between 9-48 months. Acta Med Iran 2014;52:545-51.  Back to cited text no. 12
    
13.
Sobel RK, Aakalu VK, Wladis EJ, Bilyk JR, Yen MT, Mawn LA. A comparison of endonasal dacryocystorhinostomy and external dacryocystorhinostomy: A report by the American Academy of Ophthalmology. Ophthalmology 2019;126:1580-5.  Back to cited text no. 13
    
14.
Walker RA, Al-Ghoul A, Conlon MR. Comparison of nonlaser nonendoscopic endonasal dacryocystorhinostomy with external dacryocystorhinostomy. Can J Ophthalmol 2011;46:191-5.  Back to cited text no. 14
    
15.
Leong SC, Karkos PD, Burgess P, Halliwell M, Hampal S. A comparison of outcomes between nonlaser endoscopic endonasal and external dacryocystorhinostomy: Single-center experience and a review of British trends. Am J Otolaryngol 2010;31:32-7.  Back to cited text no. 15
    
16.
Hartikainen J, Grenman R, Puukka P, Seppä H. Prospective randomized comparison of external dacryocystorhinostomy and endonasal laser dacryocystorhinostomy. Ophthalmology 1998;105:1106-13.  Back to cited text no. 16
    
17.
Yigit O, Samancioglu M, Taskin U, Ceylan S, Eltutar K, Yener M. External and endoscopic dacryocystorhinostomy in chronic dacryocystitis: Comparison of results. Eur Arch Otorhinolaryngol 2007;264:879-85.  Back to cited text no. 17
    
18.
Cokkeser Y, Evereklioglu C, Er H. Comparative external versus endoscopic dacryocystorhinostomy: Results in 115 patients (130 eyes). Otolaryngol Head Neck Surg 2000;123:488-91.  Back to cited text no. 18
    
19.
Karim R, Ghabrial R, Lynch T, Tang B. A comparison of external and endoscopic endonasal dacryocystorhinostomy for acquired nasolacrimal duct obstruction. Clin Ophthalmol 2011;5:979-89.  Back to cited text no. 19
    
20.
Somuk BT, Alim S, Sapmaz E, Demir HD, Taşkıran B, Göktaş G, et al. Comparison of endoscopic and external dacryocystorhinostomy results and analysis of patients' satisfaction. Turk Arch Otorhinolaryngol 2016;54:99-104.  Back to cited text no. 20
    
21.
Su PY. Comparison of endoscopic and external dacryocystorhinostomy for treatment of primary acquired nasolacrimal duct obstruction. Taiwan J Ophthalmol 2018;8:19-23.  Back to cited text no. 21
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22.
Jha KN, Ramalingam W. External versus endoscopic dacryocystorhinostomy: A retrospective study. Med J Armed Forces India 2009;65:23-5.  Back to cited text no. 22
    
23.
Ozer S, Ozer PA. Endoscopic vs. external dacryocystorhinostomy-comparison from the patients' aspect. Int J Ophthalmol 2014;7:689-96.  Back to cited text no. 23
    
24.
Devoto MH, Zaffaroni MC, Bernardini FP, de Conciliis C. Postoperative evaluation of skin incision in external dacryocystorhinostomy. Ophthalmic Plast Reconstr Surg 2004;20:358-61.  Back to cited text no. 24
    
25.
Huang J, Malek J, Chin D, Snidvongs K, Wilcsek G, Tumuluri K, et al. Systematic review and meta-analysis on outcomes for endoscopic versus external dacryocystorhinostomy. Orbit 2014;33:81-90.  Back to cited text no. 25
    



 
 
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