Success rates of primary probing for congenitalnasolacrimal obstruction in childrenSourabh Arora, MD,a Keyvan Koushan, MD,b and John T. Harvey, MDb

PURPOSE To determine the success rate of nasolacrimal duct probing for the treatment of congenital

Author affiliations: aMichael G.Hamilton, Ontario, Canada; bDSubmitted April 11, 2011.Revision accepted December 13Correspondence: John T. Har

Ophthalmology, St. Joseph’s CenHamilton, Ontario, L8G 5E4 CCopyright � 2012 by the Am

Strabismus.1091-8531/$36.00doi:10.1016/j.jaapos.2011.12

Journal of AAPOS

nasolacrimal duct obstruction and to identify the age at which the success rate decreases.

METHODS Records for probing procedures from 2005 to 2010, over a 56-month period, were

reviewed. Successful probing was defined as complete resolution of epiphora 3 monthsafter treatment. Success rates were compared between children \3 years of age andchildren $3 years of age at the time of the procedure.

RESULTS A total of 168 eyes (128 children, mean age 32.2 � 23.8 months) had undergone a probing

procedure, and the overall success rate was 72%. Children aged\36 months had a successrate of 78%; children aged $36 months had a success rate of 50%. Multivariate analysisdemonstrated that age at the time of procedure was a significant risk factor for failedprobing (P 5 0.035; OR, 1.67; 95% CI, 1.04-2.69), whereas sex and bilateral surgerywere not.

CONCLUSIONS The success rate of primary probing for congenital nasolacrimal duct obstruction was

significantly reduced when performed on children $3 years of age. ( J AAPOS 2012;16:173-176)

Congenital nasolacrimal obstruction (NLDO)has typical findings of epiphora, increased tearlake, and mucous discharge starting around 3 to

4 weeks of life; 80% to 100% of cases resolve by12 months.1,2 After 12 months of age, the likelihood ofspontaneous resolution decreases, and most patients aretreated with probing of the nasolacrimal drainage systemto open the blockage mechanically and with irrigationwith dilute fluorescein solution to confirm patency(probing and irrigation). Other surgical options includenasolacrimal silicone intubation (eg, using Crawfordtubes) and dacryocystorhinostomy.The optimal timing of probing and irrigation for the

treatment of NLDO has been controversial. Some studiessuggest that delaying the operation, especially after age 2, isassociated with higher failure rates.3,4 Other studies,however, suggest that delaying probing up to 36 monthsof age and even beyond is not associated with anincreased failure rate.5-7 We investigated the success rateof probing and irrigation as the primary treatment ofNLDO to identify the age at which the success rate forprobing and irrigation decreases.

DeGroote School of Medicine, McMaster University,ivision of Ophthalmology, McMaster University

, 2011.vey, MD, McMaster University, Division oftre for Ambulatory Health Services, Room 2115,anada (email: jtharvey@mcmaster.ca).erican Association for Pediatric Ophthalmology and

.151

Patients and Methods

The current study is a retrospective comparative case series of

consecutive patients on whom one of the authors (JTH) per-

formed nasolacrimal duct probing and irrigation as the primary

treatment for NLDO. McMaster University Research Ethics

Board approved this study. All medical records of patients who

underwent primary probing and irrigation for NLDO between

April 2005 and January 2010 (56 months) were reviewed. Patients

with NLDO first had a probing and irrigation. If this procedure

failed by 3 months after surgery, the patient would undergo

silicone intubation. If intubation failed, the patient would

undergo dacryocystorhinostomy. Only cases in which probing

and irrigation alone was the initial treatment were included.

The diagnosis of congenital nasolacrimal duct obstruction was

based on a history of tearing and discharge since early infancy and

confirmation of the following clinical signs: increased tear lake

size or tear pooling, enlarged lacrimal sacs, or the regurgitation

of mucous during lacrimal sac pressure. The initial examination

included evaluation of the size and placement of the lacrimal

puncta, assessment of anomalies of the lids or face, and ruling

out conjunctivitis or allergic inflammation.

In all cases of presumed nasolacrimal duct obstruction, probing

with irrigation was performed as day surgery under general anes-

thesia. In all patients, probing was performed via the lower and

upper punctum using 00 (0.90 mm diameter), 0 (1.00 mm diam-

eter), or 1 (1.10 mm diameter) Bowman probes. After dilation

of the lower punctum with a fine punctal dilator, the probe was

inserted perpendicular to the lower eyelid margin and advanced

into the ampulla. The probe was then rotated horizontally into

the lower canaliculus and advanced toward the lacrimal sac while

lateral traction was applied to the eyelid. When a hard stop was

felt, the probe was rotated 90 degrees and advanced downward

173

Table 1. Demographic/clinical characteristics

Age at time of procedure Male Female Bilateral surgery Unilateral surgery Age, months (range)

Age\3 (132 eyes) 71 eyes 61 eyes 60 eyes 72 eyes 21.1 � 5.9 (11.9-35.5)Age $3 (36 eyes) 14 eyes 22 eyes 20 eyes 16 eyes 68.5 � 26.8 (37.4-134.1)Overall (168 eyes) 85 eyes 83 eyes 80 eyes 88 eyes 32.2 � 23.8 (11.9-134)

Table 2. Success rates of probing among children\3 or $3 years of age

GroupsNumber of successes/number

in group % Success rate P valueaOdds ratio for successful

probing (95% CI)

Children\3 103/132 78% - -Children $3 18/36 50% \0.001 0.28 (0.13-0.61)Total 121/168 72.0%

aP value less than 0.05 signifies a significant difference between groups with regard to the success rate of probing based on c2 analysis.

FIG 1. Probing success rate based on age.

174 Arora, Koushan, and Harvey Volume 16 Number 2 / April 2012

into the nasolacrimal duct until a “popping” sensation was felt,

after which the probe was removed. The upper canaliculus was

likewise probed. The patency of the lacrimal drainage system

was confirmed by irrigating fluorescein-stained saline into the

lower canaliculus and aspirating it from the nasopharynx.8

After the probing, patients were given combined steroid-

antibiotic (tobramycin and dexamethasone) eye drops to be in-

stilled four times daily for 1week. Patients additionally underwent

postoperative evaluations at 1 month and 3 months. If obstructive

symptoms persisted beyond 3months after an attempted probing,

patients were offered the placement of Crawford tubes. These

cases were considered failures of probing and irrigation and the

results of silicone intubation were computed.

The study’s primary outcome was treatment success or failure 3

months after probing surgery based on an assessment of clinical

signs. Success was defined as the absence of epiphora, increased

tear lake, and mucoid/mucopurulent discharge. Demographic

and clinical data about children whose probing was successful

versus those whose probing failed were compared by Mann-

Whitney U test. The success rates of each yearly interval were

compared by c2 analysis. After it was determined that age 3 was

the point at which success rate decreased, a second analysis was

conducted comparing success rates for children age \3 or age

$3 by c2 analysis with odds ratio and 95% confidence interval.

The variables bilateral procedure, sex, and age at time of proce-

dure were assessed by a multivariate analysis for association

with a failed probing. All analyses were conducted using SPSS

version 14 (SAS Institute Inc., Cary, NC).

Results

Nasolacrimal duct probing was performed as the firstsurgical intervention on 182 eyes of 142 consecutivepatients with NLDO. Of these, 14 patients (14 eyes) whowere lost to follow-up before 3 months or for whom therewas inadequate information in the medical chart regardingthe procedure’s outcome were excluded. Our remainingstudy population was 168 eyes of 128 patients (mean age,32.2 weeks). Included in the study were 64 girls (47 success-ful, 17 failed) and 64 boys (49 successful, 15 failed). Forty

patients underwent bilateral probing, whereas 88 patientshad a unilateral procedure (Table 1). There were 102children (132 eyes) \3 years of age (mean age, 21.1 �5.9 months) and 26 (36 eyes) $3 years of age (mean age,68.5 � 26.8) (Table 2).

The overall success rate of probing was 72.0% (121/168). The highest success rates, based on yearly intervals,were in children \24 months of age (76%) and children24-36 months of age (84%) (Figure 1). Two 10-year-oldchildren had a success rate of 100%. The success rate forchildren\3 years of age was 78% (103/132); for children$3 years of age, the success rate was 50% (18/36)(P\0.001). The odds ratio for success in children\3 yearsof age was 0.28 (0.13-0.61) (Table 3). The mean age fora successful procedure was 29.3 weeks; the mean age forchildren with a failed procedure was 39.9 weeks (P 50.0083). A multivariate analysis showed that age atthe time of procedure (P 5 0.035; OR, 1.67; 95% CI,1.04-2.69) was a significant risk factor associated withfailed probing. Thus there appeared to be a trend wherebythere was a reduction in success rate after age 3 years(36 months). Sex (P 5 0.99) and bilateral surgery

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Table 3. Results of multivariate logistic regression analysis: Risk factors predictive of probing failure

Risk factor Successful probing Failed probing Relative risk for failure (95% CI)

Male sex 62 23 1.01 (0.50-2.00)Bilateral surgery 57 23 0.92 (0.46-1.83)Age at time of procedure (overall) 29.3 � 20.5 (mean) 39.9 � 28.8 (mean) 1.67 (1.04-2.69)

Table 4. Results of multivariate logistic regression analysis: Risk factors predictive of failure of probing

Risk factor Successful probing Failed probing Relative risk for failed probing (95% CI)

Male gender 62 23 1.01 (0.50-2.00)Bilateral surgery 57 23 0.92 (0.46-1.83)Age at time of procedure (overall) 29.3 � 20.5 (mean) 39.9 � 28.8 (mean) 1.67 (1.04-2.69)

Volume 16 Number 2 / April 2012 Arora, Koushan, and Harvey 175

(P 5 0.82) were not significant risk factors for failed prob-ing (Table 4).

Discussion

Our primary surgical intervention for congenital NLDOwas probing and irrigation. There was a significant 36%relative reduction in probing and irrigation success forchildren$3 years of age at the time of procedure comparedto children\3 years of age. Our study’s overall success rate(72.0%) is comparable to previous studies. Honavar andcolleagues9 reported a similar overall success rate of73%, with a median age of 33 months. The Pediatric EyeDisease Investigator Group (PEDIG)’s prospective studyin 2008 showed a higher success rate (78%); however, themean age of their study population (13.6 months) wasmuch lower than that of our patients.7

Some studies recommend that intubation beperformed only in children older than 1 year becauseyounger children often experience spontaneousresolution of NLDO.2,10,11 Thus a wait-and-see approachhas been recommended, which is followed at ourinstitution.1 Many studies have shown success rates to behigher at younger ages, especially among children\2 yearsof age.3,4,12,13 Limbu and colleagues3 demonstrated 90%success in children \2 years of age and 73% success inchildren .2. Potential reasons for this difference fromour study (76%) include patient selection and racial/ethnicvariation as this study was conducted in Nepal. Limbu andcolleagues3 had identical clinical criteria to assess proce-dure success; however, they made this decision at the1-month follow-up and thus they may have missed somepatients who had recurrence of symptoms beyond thattime. Furthermore, their surgical techniques differedslightly from ours: Limbu and colleagues3 used differentsized probes specific to a patient’s age; furthermore, theydid not use fluorescein irrigation after the probing. Veryfew other studies within the last 10 years achieved a successrate of 90% or higher14,15; older studies showed highersuccess rates in children\2 years of age.4,6,9,12

Children older than 2 years can be successfully treatedwith probing.5,7,16-19 Maheshwari16 reported a success

Journal of AAPOS

rate of 81% in children older than 2 years (mean age, 45months). Honavar and colleagues9 reported a 97.1%success rate in children\3 years of age and a significantreduction among their group of children older than 36months (75%). In the PEDIG study,7 37 probing proce-dures performed on children aged 24 to 36 months showeda success rate of 79%, and this was equivalent success to the421 probings for children aged 12-36 months. Our resultsare comparable to the PEDIG study for children under age36 months. Furthermore, our decreased success rate at age3 and beyond (50%, n 5 36) is comparable to that groupfrom the PEDIG study (57%, n 5 11).

Our study is difficult to interpret due to the wide varia-tion in success rates among yearly interval groups as well asthe small sample size in older age groups (Table 1).However, using age 3 as a cutoff demonstrated a visibledifference in success rate when analyzing for trend.Down syndrome is also thought to be a risk factor for failedprobing, and although we examined this, our resultsyielded only four eyes in this group, with a success rate of50%. These numbers were too small to be statisticallymeaningful. Other clinical factors, such as the nature ofthe obstruction, could not be extracted reliably from themedical records; however, such factors have been reportedas contributory to success rates.20,21

In conclusion, our study demonstrates that probingwith irrigation is a successful primary treatment for con-genital NLDO in children \3 years of age. Based onour data and the results of numerous other studies, thetransition point when probing with irrigation becomesless successful as primary treatment is likely somewherebeyond age 3 but depends on other clinical factors. Wesuggest that future prospective studies investigate theoptimal age for primary probing for NLDO while alsoconsidering a practical approach to grading the clinicalseverity of the obstruction.

References

1. el-Mansoury J, Calhoun JH, Nelson LB, Harley RD. Results of lateprobing for congenital nasolacrimal duct obstruction. Ophthalmol-ogy 1986;93:1052-4.

176 Arora, Koushan, and Harvey Volume 16 Number 2 / April 2012

2. Kapadia MK, Freitag SK, Woog JJ. Evaluation and management ofcongenital nasolacrimal duct obstruction. Otolaryngol Clin NorthAm 2006;39:959-77, vii.

3. Limbu B, Akin M, Saiju R. Age-based comparison of successful prob-ing in Nepalese children with nasolacrimal duct obstruction. Orbit2010;29:16-20.

4. Mannor GE, Rose GE, Frimpong-Ansah K, Ezra E. Factors affectingthe success of nasolacrimal duct probing for congenital nasolacrimalduct obstruction. Am J Ophthalmol 1999;127:616-7.

5. Kashkouli MB, Kassaee A, Tabatabaee Z. Initial nasolacrimal ductprobing in children under age 5: cure rate and factors affectingsuccess. J AAPOS 2002;6:360-63.

6. RobbRM. Success rates of nasolacrimal duct probing at time intervalsafter 1 year of age. Ophthalmology 1998;105:1307-10.

7. Repka MX, Chandler DL, Beck RW, et al. Primary treatment ofnasolacrimal duct obstruction with probing in children youngerthan 4 years. Ophthalmology 2008;115:577-84.e3.

8. Steindler P, Mantovani E, Incorvaia C, Parmeggiani F. Efficacy ofprobing for children with congenital nasolacrimal duct obstruction:A retrospective study using fluorescein dye disappearance test and lac-rimal sac echography. Graefes Arch Clin Exp Ophthalmol 2009;247:837-46.

9. Honavar SG, Prakash VE, Rao GN. Outcome of probing for congen-ital nasolacrimal duct obstruction in older children. Am JOphthalmol2000;130:42-8.

10. Schellini SA, Ferreira Ribeiro SC, Jaqueta E, Padovani CR. Sponta-neous resolution in congenital nasolacrimal obstruction after 12months. Semin Ophthalmol 2007;22:71-4.

11. Takahashi Y, Kakizaki H, Chan WO, Selva D. Management of con-genital nasolacrimal duct obstruction. Acta Ophthalmol 2010;88:506-13.

12. Paul TO, Shepherd R. Congenital nasolacrimal duct obstruction:Natural history and the timing of optimal intervention. J PediatrOphthalmol Strabismus 1994;31:362-7.

13. Thongthong K, Singha P, Liabsuetrakul T. Success of probing forcongenital nasolacrimal duct obstruction in children under 10 yearsof age. J Med Assoc Thai 2009;92:1646-50.

14. Frick KD, Hariharan L, Repka MX, Chandler D, Melia BM,Beck RW; Pediatric Eye Disease Investigator Group. Cost-effective-ness of 2 approaches to managing nasolacrimal duct obstruction ininfants: The importance of the spontaneous resolution rate. ArchOphthalmol 2011;129:603-9.

15. Shrestha JB, Bajimaya S, Hennig A. Outcome of probing undertopical anesthesia in children below 18 months of age with congenitalnasolacrimal duct obstruction. Nepal Med Coll J 2009;11:46-9.

16. Maheshwari R. Results of probing for congenital nasolacrimal ductobstruction in children older than 13 months of age. Indian J Oph-thalmol 2005;53:49-51.

17. Zilelioglu G, Hosal BM. The results of late probing in congenital na-solacrimal duct obstruction. Orbit 2007;26:1-3.

18. Zwaan J. Treatment of congenital nasolacrimal duct obstructionbefore and after the age of 1 year. Ophthalmic Surg Lasers 1997;28:932-6.

19. Maheshwari R, Maheshawri S. Late probing for congenital nasolacri-mal duct obstruction. J Coll Physicians Surg Pak 2007;17:41-3.

20. Maheshwari R. Success rate and cause of failure for late probingfor congenital nasolacrimal duct obstruction. J Pediatr OphthalmolStrabismus 2008;45:168-71.

21. Kashkouli MB, Beigi B, Parvaresh MM, Kassaee A, Tabatabaee Z.Late and very late initial probing for congenital nasolacrimal ductobstruction: what is the cause of failure? Br J Ophthalmol 2003;87:1151-3.

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