Factors affecting the need for silicon tube implantation in cases of congenital dacriostenosis: Time of delivery, mode of delivery and age of operation

doi:10.21203/rs.3.rs-2352886/v1

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Factors affecting the need for silicon tube implantation in cases of congenital dacriostenosis: Time of delivery, mode of delivery and age of operation

https://doi.org/10.21203/rs.3.rs-2352886/v1

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published 29 Jun, 2023

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Purpose

To evaluate the delivery time, mode of delivery, age at the time of operation, and surgical methods applied in cases of congenital nasolacrimal duct obstruction (CNLDO).

Methods

This study retrospectively included a total of 207 eyes of 160 patients who underwent surgery for CNLDO between February 2012 and April 2021. According to their age at the time of operation, the patients were divided into 0–12, 12–24, 24–36, 36–48 and > 48 months groups. The cases were evaluated as term/preterm according to the delivery time and cesarean section/vaginal delivery according to the mode of delivery. The surgical methods applied were examined as probing alone and probing plus silicone tube implantation.

Results

Of the cases, 190 (91.8%) were born at term and 17 (0.08%) were born preterm, and there was no statistically significant difference in the silicone tube implantation rates according to the time of delivery. The rate of tube implantation was statistically significantly higher in the vaginal delivery group than in the cesarean section group (p = 0.001; p < 0.01). The rate of silicone tube implantation was higher in those who were older than the age of the operation.

Conclusions

Although the rate of those who were born by cesarean section was higher in probing cases, those who required silicone intubation were more common in those who were born vaginally. This suggests that dacryostenosis in the vaginally born cases resulted from a persistent structural and anatomical obstruction despite the presence of a high intrauterine pressure increase and enzymatic lysis.

Congenital dacriostenosis

silicone tube implantation

mode of delivery

Eye watering and burring occur in 2–20% of newborns, starting from the first month after birth [1]. Continuous watering from the neonatal period, along with adhesions in eyelashes, redness in eyes, conjunctivitis findings, and the red and swollen appearance of the lacrimal sac suggest the presence of nasolacrimal duct obstruction. The valve of Hasner, where the nasolacrimal duct opens to the inferior meatus, is opened in 85–90% of newborns as a result of increased intrauterine pressure and the lysis effect of enzymes released from the amniotic membrane during delivery. In the literature, it has been reported that the full opening of the membrane can take up to 24 months [2]. An intact membrane in the valve of Hasner causes the symptoms of dacryostenosis. In 85% of congenital nasolacrimal duct obstruction (CNLDO) cases, symptoms improve within the first 12 months without surgical intervention, and massaging and antibiotic drops are recommended during this period, while symptoms become permanent in 2–6% of cases [3, 4]. Surgical treatment is required in cases that do not improve despite the massage application. In surgical treatment, probing is usually sufficient in the younger age group and membranous uncomplicated cases. In later ages, complicated cases, and those that do not improve with probing, monocanalicular or bicanalicular silicone tube implantation is performed, and dacryocystorhinostomy is also undertaken when necessary. If left untreated, CNLDO can lead to amblyopia or life-threatening conditions, such as orbital cellulitis [1–4].

Many studies have investigated the effects of premature birth and cesarean delivery on the development of CNLDO, with some showing the effects of these factors while others reporting no significant relationship [5–9].

In this study, we investigated the effects of delivery time and mode of delivery on surgical methods and results of surgical treatment in patients that underwent surgery for CNLDO.

The study included a total of 207 eyes of 160 pediatric patients who were operated on for CNLDO in a tertiary hospital between February 2017 and April 2021. The protocol of the study, which was planned with the retrospective analysis of recorded files, was in accordance with the principles of the Declaration of Helsinki and approved by our institutional review board (Date: 06.05.2021, umber: 6/20).

Complete ophthalmological examinations were performed by taking the detailed anamnesis of all the cases. In the biomicroscopic examination, the puncta, sac region, and eyelids were examined. The presence of swelling in the sac region with palpation, pus material from the puncta, and pain was evaluated.

The diagnosis of CNLDO was made based on an enlarged tear meniscus and the persistence of fluorescein 5 minutes after 2% was dropped into the conjunctival sac in the fluorescein disappearance test. If the patients with CNLDO were younger than nine months, massaging on the pouch and antibiotic drop treatment for burring were recommended. Surgical intervention was performed in complicated cases, such as the development of dacryocystitis even in younger patients.

Probing was applied to the patients whose symptoms persisted despite regular massage therapy. In cases of complicated obstruction, Crawford bicanalicular silicone tube implantation was performed peroperatively.

In our clinic, surgical probing is performed with endoscopy guidance under general anesthesia. After dilating the puncta for primary probing, the Bowman lacrimal probe (Size 00) was advanced through the canaliculi, ampulla, and sac until it reached the bony tissue. Upon reaching the hard end, the probe was slightly pulled back and directed 90° downwards. The probe was advanced until it opened the membrane of Hasner. Simultaneously, using the endoscope, it was confirmed that the probe had reached the inferior meatus. Endoscopic imaging allowed for the observation of additional pathologies in the nose. Turbinate medialization was performed during probing in cases where necessary. During advancement with the probe, if more than normal resistance was observed at the punctum, canaliculi, sac, or nasolacrimal duct levels, this was considered as ‘complicated obstruction’, and bicanalicular silicone tube implantation was performed together with primary probing. The cases in which the membrane of Hasner opened without abnormal resistance during probing were defined as ‘simple membranous obstruction’.

Only the patients who attended their follow-up examinations for at least six months were included in the study. Cases with punctal agenesis, coloboma, eyelid abnormalities, additional ophthalmic pathologies, nasal and throat pathologies, and congenital malformations, and those that had previously undergone surgery for CNLDO were excluded.

The demographic data (age, gender, and laterality) of the cases were evaluated. The cases born at a gestational age of < 37 weeks were defined as preterm and those born at a gestational age of ≥ 37 weeks were defined as term. According to the mode of delivery, the cases were divided into cesarean section and vaginal delivery groups. Surgical success rates were evaluated according to the follow-up examinations of the cases that underwent probing alone and those in which both probing and silicone tube implantation were performed. Improvement in symptoms and a negative result in the conjunctival fornix fluorescein disappearance test during the follow-up examinations were considered as surgical success.

Statistical Analysis

The Number Cruncher Statistical System (NCSS) software was used for statistical analyses. Descriptive statistical methods (mean, standard deviation, median, frequency, percentage, minimum, and maximum) were used when analyzing the study data. The Pearson chi-square, Fisher’s exact, and Fisher-Freeman-Halton tests were used to compare qualitative data. Statistical significance was accepted as p < 0.05.

Data were obtained from a total of 207 eyes (94 female, 113 male) of 160 patients. The ages of the cases included in the study varied between 9 and 76 months. The mean age was found to be 32.29 ± 25.60 months. According to the age at the time of operation, 8.7% (n = 18) of the cases were 0–12 months, 47.3% (n = 98) were 12–24 months, 16.9% (n = 35) were 24–36 months, 13.5% (n = 28) were 36–48 months, and 13.5% (n = 28) were 48 months and over. CNLDO was bilateral in 29.3% (n = 47) of the cases and unilateral in 70.6% (n = 113). Of the 207 eyes that were operated on, 50.7% (n = 105) were right eyes and 49.3% (n = 102) were left eyes (Fig. 1) (Table 1).

Table 1

Distribution of Descriptive Characteristics
Age of operation (month)	Average ± Sd	32,29 ± 25,60
	Medyan (Min-Max)	22 (9-144)
	0–12 month	18 (8,7)
	12–24 month	98 (47,3)
	24–36 month	35 (16,9)
	36–48 month	28 (13,5)
	> 48 month	28 (13,5)
Gender	Female	94 (45,4)
Gender	Male	113 (54,6)
Mode of Operation	Probing	170 (82,1)
Mode of Operation	Silicone tube	37 (17,9)
Type of Delivery	Vaginal Delivery	81 (39,1)
Type of Delivery	Cesarean Delivery	126 (60,9)
Birth Time	Term	190 (91,8)
Birth Time	Preterm	17 (8,2)
Laterality	Right	105 (50,7)
Laterality	Left	102 (49,3)

Silicone tube implantation was performed in addition to probing in 17.9% (n = 37) of the cases, while only probing was undertaken in 82.1% (n = 170). The mode of delivery was vaginal delivery in 39.1% (n = 81) of the cases and cesarean section in 60.9% (n = 126).

A statistically significant difference was found in the silicone tube implantation rates according to the patient age at the time of operation (p = 0.001; p < 0.01). The rate of silicone tube implantation was significantly higher in the children that underwent surgery when aged over 48 months compared to those with an operation age of 0–12 months, 12–24 months, 24–36 months, and 36–48 months. Similarly, the rate of silicone tube implantation was significantly higher in the 37-48-months group at the time of operation compared to the 25-36-months group (Fig. 2).

Silicone tube implantation was required in 13 of the 126 cases (10.3%) in the cesarean section group and 24 (29.6%) of the 81 cases born vaginally, indicating a statistically significantly higher rate in the latter (p = 0.001; p < 0.01) (Fig. 3) (Table 2).

Table 2

Evaluation of the Mode of Operation According to Descriptive Characteristics
		The Mode of Operation		p
		Probing	Silicone Tube
		n (%)	n (%)
Operation Age (month)	0–12 month	16 (88,9)	2 (11,1)	^a0,001**
	12–24 month	87 (88,8)	11 (11,2)
	24–36 month	34 (97,1)	1 (2,9)
	36–48 month	23 (82,1)	5 (17,9)
	> 48 month	10 (35,7)	18 (64,3)
Gender	Female	78 (83,0)	16 (17,0)	^a0,770
Gender	Male	92 (81,4)	21 (18,6)
Type of Delivery	Vaginal delivery	57 (70,4)	24 (29,6)	^a0,001**
Type of Delivery	Cesarean delivery	113 (89,7)	13 (10,3)
Birth Time	Term	157 (82,6)	33 (17,4)	^b0,514
Birth Time	Preterm	13 (76,5)	4 (23,5)
Laterality (n = 207)	Right	84 (80,0)	21 (20,0)	^a0,418
Laterality (n = 207)	Left	86 (84,3)	16 (15,7)
^aPearson Chi-Square Test ^bFisher’s Exact Test **p < 0,01

Of the 17 preterm cases, 3 (17.6%) were born vaginally and 14 (82.3%) were born via cesarean section, and 13 (76.5%) underwent probing alone while four (23.5%) additionally required silicone tube implantation. Probing was sufficient in all three preterm cases born vaginally. While only probing was performed in 157 (82.6%) of the 190 term cases, silicone tube implantation was also required in 33 (17.4%).

Although the rate of silicone tube implantation in the premature cases was higher than in the term cases, the difference was not statistically significant (p > 0.05). There was also no statistically significant difference in the silicone tube implantation rates of the preterm and term cases according to the delivery time (p > 0.05) (Table 2).

The distribution of the mode and time of delivery did not statistically significantly differ according to the patient age at the time of operation (p > 0.05) (Table 3).

Table 3

Evaluation of Delivery Type and Time of Delivery by Age of Operation
		Operation Age (months)					P
		0–12 month	12–24 month	24–36 month	36–48 month	> 48 month
		n (%)	n (%)	n (%)	n (%)	n (%)
Type of Delivery	Vaginal Deivery	9 (50,0)	39(39,8)	11(31,4)	11(39,3)	11(39,3)	^a0,776
Type of Delivery	Cesaren Delivery	9 (50,0)	59(60,2)	24(68,6)	17(60,7)	17(60,7)
Birth Time	Term	18(100,0)	89(90,8)	32(91,4)	27(96,4)	24(85,7)	^c0,490
Birth Time	Preterm	0 (0,0)	9 (9,2)	3 (8,6)	1 (3,6)	4 (14,3)
^aPearson Chi-Square Test ^cFisher Freeman Halton Test

After the operation, symptoms improved in 198 (95.6%) of the 207 eyes. Watering and burring recurred in nine eyes. Of the nine eyes with persistent symptoms, five had been born vaginally and four had been born via cesarean section. Silicone tube implantation was performed in three of the nine eyes with recurrence and probing alone in the remaining six. Surgical treatment was repeated in the recurrent cases. Secondary probing was applied to five eyes, probing and silicone tube implantation in one eye, and dacryocystorhinostomy was in the remaining three eyes. Of the five cases in which secondary probing was performed, three had been born vaginally and two by cesarean section, and one patient that underwent probing and silicone tube implantation had been born via cesarean section. Of the three eyes with recurrence that underwent dacryocystorhinostomy, two had been born vaginally and one via cesarean section.

Studies have shown that many factors, such as premature delivery, intrauterine infections, maternal age, medication use during pregnancy, genetic and environmental characteristics, and mode of delivery may be effective in the development of CNLDO [10, 11]. Although the canalization of the nasolacrimal duct by normal columnar epithelial cells is usually completed by the end of the intrauterine sixth month, it may sometimes be delayed until the postpartum period [12].

Lorena and colleagues investigated the incidence of CNLDO in 200 premature and 200 term-born children in their study, they showed that CNLDO developed in 16% of premature cases, while term developed in 3.5% of cases. The authors stated that a conservative treatment approach was applied in 30 of the 32 premature cases and five of the seven term cases. In the same study, the premature group had a higher rate of CNLDO development but lower rate of surgical intervention requirement than the term group, suggesting that the development of the nasolacrimal duct in premature cases continues in the postnatal period and significantly improves with the provision of adequate maturation and conservative treatment.

In our study, 17 (8.2%) of the 207 cases that underwent surgery for CNLDO were in the preterm delivery group and 190 (91.8%) were in the term delivery group. According to the 2019 data of the Turkish General Directorate of Public Health, the rate of premature birth in the Mediterranean Region is 11.1%, which indicates that the rate of the preterm cases in our study was lower (8.2%). Therefore, it can be concluded that the need for surgical treatment is less in preterm cases than in term cases, despite the high rate of CNLDO in those born prematurely. Since our study group consisted of only operated cases, we do not know the rate of CNLDO in all the preterm (operated and non-operated) cases. However, according to our results, the rate of the preterm cases with CNLDO requiring surgical treatment (8.2%) was lower compared to the rate of premature birth in the general Turkish population (11.1%), suggesting that premature infants developing CNLDO respond to massage therapy at a high rate. In our study, 14 of the 17 preterm cases had been born via cesarean section. In light of these results, to arrive at a more definitive conclusion, it is also necessary to know the rates of preterm and cesarean deliveries in CNLDO cases that improve with massage therapy without the need for surgery.

In our study, there was no significant difference between the term and preterm cases in terms of the rate of silicone tube implantation. Although prematurity alone can be the cause of an incomplete and obstructed nasolacrimal duct, the rate of simple or complicated type of obstruction development in preterm cases was similar to the term cases in our study.

In the treatment of CNLDO, a conservative approach is generally applied in the first nine to 12 months after birth, and surgical applications are undertaken in patients aged over 12 months. Many studies have shown that surgical success rates are high at early ages and decrease as patient age at the time of operation increases [13, 14].

In our study, the rate of surgical success defined as complete improvement in symptoms was determined to be 95.6%, which is higher than reported in the literature (75–89%). We consider that the surgical intervention being performed under endoscopy guidance in all our cases was effective in our increased success rate. Endoscopic imaging during the surgical procedure allowed observing accompanying intranasal pathological conditions and performing turbinate medialization in necessary cases.

The absence of a lytic effect of enzymes and a high intrauterine pressure in primary cesarean delivery leads to the presence of an intact membrane on the valve of Hasner. In vaginally born cases, the membrane on the valve of Hasner is mostly opened by the lytic effects of enzymes and a high intrauterine pressure. In cases where this valve does not open at the time of birth, if there is no anatomical predisposition to possible CNLDO, symptoms usually resolve spontaneously or with the massage application within the first six months after delivery. In a study by Tavakoli et al. [7], it was observed that nasolacrimal duct obstruction did not resolve spontaneously or by massage in primary cesarean section cases, and the rate of surgical intervention requirement was higher in this group compared to the vaginal delivery group. However, Tavakoli et al. defined all the probing cases as complicated obstruction. In contrast, we defined the CNLDO cases in which only probing was applied as ‘simple membranous obstruction’ and those requiring silicone tube implantation as ‘complicated obstruction’. Furthermore, the majority of the cases in the study of Tavakoli et al. consisted of those that did not require surgery and improved with conservative treatment. We did not include patients who received conservative treatment or did not receive any treatment in our study. Vaginally born cases requiring surgical intervention due to CNLDO have a persistent obstruction, although they have been exposed to a high intrauterine pressure and lytic enzymes. In our study, the rate of the patients with complicated obstruction who underwent silicone tube implantation was found to be higher in the vaginal delivery group than in the cesarean section group. Tavakoli et al. reported that 60.5% of the 104 cases with CNLDO were born via cesarean section and 39.4% were born vaginally [7]. The authors applied massage therapy to 54 of the 104 patients and surgical probing to 50. Thirty-seven (58.7%) of the 50 cases in which they applied probing had been born via cesarean section and the remaining 13 (31.7%) had been born vaginally, which are similar to the rates obtained in our study. On the other hand, in the previous study, probing was insufficient in 29 (58%) of the 50 cases in which probing was applied, and this rate is considerably higher than reported in the literature (11–25%). Tavakoli et al. also reported that 25 of the 29 cases with surgical failure had been born via cesarean section and four vaginally. They performed probing in nine of the 13 vaginally born cases that did not improve with massage therapy and required surgery, and additional surgery was required in four of these patients. They also noted that among the patients who had been born vaginally and underwent surgical intervention for CNLDO, probing alone was not sufficient in 30% and additional surgery was required. They reported that cases born via cesarean section required additional intervention at a high rate, but they defined their mechanism as ‘complex’. The number of patients that underwent surgical intervention in that study was less than in our study. We did not include cases that improved with massage therapy in our study. All our cases were those that required surgical intervention, and our sample constitutes the largest series in the literature, in which surgical intervention methods and mode of delivery were examined. In our study, surgery was not successful in nine (4%) of the 207 eyes that underwent probing and/or silicone tube implantation. Of the nine cases in which surgery was insufficient, five had been born vaginally and four by cesarean section.

In our clinical practice, we use endoscopic imaging during surgery to identify difficult-to-probe, complicated cases in which to apply silicone tube implantation simultaneously with probing. In our study, among the 207 eyes that underwent surgery, only probing was performed in 170, and silicone tube implantation was additionally required in 37. Of the 37 cases that required silicone tube implantation, which we defined as complicated obstruction, 24 had been born vaginally and 13 via cesarean section. Of the 170 cases that underwent probing, 113 had been born via cesarean section and 57 vaginally. We observed a higher rate of simple membranous CNLDO in our cesarean section cases compared to those born vaginally. The cases requiring silicone tube implantation had a higher rate of vaginal delivery.

Infants born via primary cesarean section are not exposed to an increased intrauterine pressure and lytic enzymes, which are considered to be effective mechanisms in the development of CNLDO [5–8, 15]. Therefore, if the mode of delivery had been vaginal in some of our cases that underwent primary cesarean section, CNLDO may have not developed. However, in some of the cases born vaginally, CNLDO still developed despite the presence of an increased intrauterine pressure and lytic enzymes. We consider that these cases had complicated obstruction due to their anatomical structures, and therefore they also required a higher rate of silicone tube implantation.

As a missing aspect of our study; we do not know whether cesarean births are primary cesarean or secondary cesarean births. Studies have shown that primary cesarean delivery is effective in the development of congenital nasolacrimal duct stenosis [5, 7–8]. Bilge, on the other hand, showed that cases with CNLDO in cesarean section, the majority of which were formed by those born by secondary cesarean section, developed 3.7 times more often than cases born vaginally [16].

The increase in intrauterine pressure is mostly seen in the second stage of labor when the Valsalva maneuvers are applied. Therefore, a sufficiently high pressure reaching the membrane of Hasner and affecting its opening may not have occurred in our secondary cesarean section cases. We do not know exactly at what stage of labor secondary cesarean delivery was required and how much intrauterine pressure increased.

In our study, the majority of CNLDO cases requiring surgical treatment were those born via cesarean section, but the presence of complicated obstruction requiring silicone tube implantation was higher in those born vaginally. In addition, as the patient age at the time of operation increased in the CNLDO cases, fibrotic obstruction occurred regardless of the mode of delivery, leading to the need for silicone tube implantation or further surgical intervention.

Statements and Declarations

Funding

The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.

Author Contributions

HDİ, SY designed the study and drafted the manuscript; HDİ, SY conducted the study; ME helped in data collection, analysis and interpretation. All authors read and approved the final manuscript

Competing Interests

The authors have no relevant financial or non-financial interests to disclose.

Ethics approval

This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by our institutional review board.

Consent to participate

Informed consent was obtained from all individual participants included in the study.

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No competing interests reported.

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Journal Publication

published 29 Jun, 2023

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Editorial decision: Major revision
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You are reading this latest preprint version

Factors affecting the need for silicon tube implantation in cases of congenital dacriostenosis: Time of delivery, mode of delivery and age of operation

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