Partial orbital lobe dacryoadenectomy for refractory epiphora

Abstract

Purpose:

To evaluate the efficacy of partial orbital lobe dacryoadenectomy (POLD) in patients with refractory epiphora.

Design:

Prospective interventional study.

Setting:

Tertiary eye care institute.

Study Population:

Consecutive patients with refractory epiphora due to proximal lacrimal outflow system obstruction, multiple failed dacryocystorhinostomy, and postdacryocystectomy. All patients underwent preoperative assessment with Munk score, Schirmer-I Score, tear breakup time, corneal fluorescein staining, anterior segment OCT (AS-OCT), and CT scans of the orbit.

Intervention:

Partial removal of the lacrimal gland orbital lobe under local anesthesia.

Main Outcome Measure:

Reduction in epiphora. Objective and subjective evaluation was repeated at postoperative 1-week, 1-month, and 3-month visits.

Results:

Out of 17 patients enrolled, one had congenital punctal agenesis, three had acquired punctal effacement, and 13 had proximal bicanalicular obstruction. The mean age was 48.8 ± 18.6 years. All patients underwent POLD, with removal of 50–60% of the orbital lobe of the lacrimal gland. The mean follow-up duration was 5.7 months. At 3-month follow-up visit, the average reduction in Munk score was 60%, the average reduction in Schirmer-I value was 35.2%, and the average reduction in tear film height on AS-OCT was 35.9% (all statistically significant, P < 0.05), from the initial visit. None of the patients developed signs and symptoms of dry eye disease.

Conclusion:

POLD is an effective and safe procedure for patients with refractory epiphora in the short term. Further studies are needed to establish efficacy in the long term.

Severe epiphora is a nuisance for patients, which can cause social embarrassment, apart from affecting the vision-related quality of life.[1] Constant epiphora can also cause periocular skin maceration. Refractory epiphora due to punctual agenesis, complete punctal occlusion, multiple failed dacryocystorhinostomy (DCR), postdacryocystectomy (DCT), or nonsalvageable proximal lacrimal system obstruction is challenging to treat. These conditions do not respond to conventional medical management or standard lacrimal surgeries. Treatment options in such conditions include creation of a new drainage pathway to bypass the proximal lacrimal drainage system by means of a conjunctivodacryocystorhinostomy (CDCR) or lacrimal gland (LG) targeted therapies to reduce tear production.[2,3] CDCR is a technically challenging procedure and carries a high rate of postoperative complications.[4,5] Therapies targeting the LG aim to reduce the aqueous volume, by means of intraglandular Botulinum toxin A (BTA) injection or partial excision of the orbital lobe of the lacrimal gland. BTA injection in the lacrimal gland is a routinely performed procedure; however, the success rates, injection doses, epiphora improvement, and need for reinjections are variable across literature, with no standardization.[6] Partial orbital lobe dacryoadenectomy (POLD) is a resurgent surgical technique that debulks the lacrimal gland volume to reduce tear production.[3] Epiphora reduction after POLD surgery has been described in two recent Indian studies; however, the literature on this technique remains scanty.[3,7] We describe the efficacy, safety, and outcomes of POLD in our experience.

Methods

This prospective interventional study was conducted at a tertiary eye care institute in North India. Patients who underwent POLD surgery from January 2021 to January 2024, with a minimum postoperative follow-up duration of 3 months were enrolled in the study. Informed written consent was obtained from the participants preoperatively in their language before enrolling them in the study. Institutional review board and ethics committee approval was taken for the study, and the study adhered to the tenets of the Declaration of Helsinki. Demographic data and detailed history were collected, and all patients underwent detailed ophthalmic examination. Punctal evaluation on slit lamp was performed for all patients. Syringing was done to check for lacrimal system patency, and probing was performed to assess the level of blockage, if any. Patients with complete punctal effacement, proximal bicanalicular block, and multiple failed DCR and post-DCT patients were explained the options of CDCR, lacrimal gland BTA injection, and POLD. Patients who consented to POLD were enrolled in the study and underwent further evaluation, including MUNK scoring, Schirmer’s I test, tear break-up time (TBUT) measurement, and tear film height (TFH) measurement on slit lamp and AS-OCT. Patients with concurrent ocular surface pathologies were excluded from the study. Preoperative CT orbit scans were performed to assess the lacrimal gland. Post surgery, the same evaluation parameters were performed at 1-week, 1-month, and 3-month visits.

Statistical analysis

Data tabulation was performed in MS Excel spreadsheet, and statistical analysis was done using IBM SPSS v23. For descriptive statistics description, mean and standard deviations were used, and for categorical variables, percentages were used. Sample ‘t’ test analysis was done for group comparisons in continuously distributed data, and Wilcoxon test or Kruskal–Wallis test was done for non-normal data distribution. For categorical data, Chisquared test analysis was performed. P < 0.05 was considered statistically significant.

Surgical technique

All surgeries were performed by a single surgeon (SD) under local anesthesia. Frontal nerve block and local infiltration using 2% lignocaine with 1:200000 adrenaline mixture were used for all the patients. Lateral lid crease incision was given using a 15 no. blade, followed by orbicularis muscle dissection using monopolar radiofrequency cautery. The septum was identified and incised near the superotemporal orbital rim. The preaponeurotic fat pad was bluntly dissected to expose the orbital lobe of the lacrimal gland (LG). Blunt dissection was performed all around the LG to reflect it from the lacrimal gland fossa. The neurovascular bundle was identified and gently retracted medially. Care was taken to avoid manipulating the isthmus of the gland and the palpebral lobe. The lateral lobe of the LG was visualized and approximately 50%–60% of the lateral orbital lobe of the gland was excised under direct visualization, with due care to stay away from the ductules and the palpebral lobe. The incision was closed using 6-0 nonabsorbable suture. Excised LG tissue was sent for histopathological evaluation. The remnant lacrimal gland was reposited in the fossa, without refixation. The surgical steps of the technique and the excised part of the lacrimal gland are elucidated in Fig. 1.

Figure 1.

Surgical steps of partial orbital dacryoadenectomy. Lateral eyelid crease incision used to approach the orbital lobe of the lacrimal gland (a). Dissection was done in the skin orbicularis plane to reach the superolateral orbit and orbital septum (b). Orbital septum incised; blunt dissection done to expose the orbital lobe of the gland (c). The lacrimal artery can be seen around the medial aspect of the gland (yellow arrowhead) (d). The lacrimal artery retracted medially (yellow arrowhead). The lateral part of the orbital lobe of the gland was excised (e). Gross photograph of the excised part of the lacrimal gland (f)

Postoperative follow-up

Broad spectrum oral antibiotic, oral analgesic, topical antibiotic eyedrops, and betadine cleaning of wounds were advised for 1 week in the postoperative period. Skin suture removal was performed at 1-week follow-up visit. Postoperative follow-ups were scheduled on the first postoperative day, 1 week, 1 month, and 3 months. Subjective and objective evaluation of epiphora was performed at each visit. Subjective improvement was graded according to percentage reduction in watering as follows: 0% (no improvement – same as preoperative state), 1–25% (mild improvement), 26–50% (moderate improvement), 51–75% (good improvement), and >75% (excellent improvement).

Results

This was a pilot study, and patients were enrolled from January 2021 to January 2024 with a minimum physical follow-up duration of 3 months. A single side of 17 patients underwent POLD, out of which 10 were females and 7 were males (1.42:1 female predominance). The mean age at presentation was 48.8 ± 18.6 years (range 15–81 years). The most common etiology was bicanalicular obstruction (76.5%, n = 13). Among these cases of bicanalicular obstruction, six patients had history of facial trauma, two patients were on antiglaucoma drug use, and five cases were idiopathic. The other causes were congenital punctal agenesis (n = 1, 5.8%) and acquired punctal effacement (n = 3, 17.7%). One patient (5.8%) had received injection BTA in the LG 1 year prior to presentation but subsequently opted for surgery. The average preoperative Munk score was 4, which reduced a statistically significant value of 1.6 at 3-month postoperative visit (60% reduction, P < 0.001). The mean preoperative Schirmer’s score and TBUT were 27.8 mm at 5 mins and 14.6 seconds, respectively. None of the patients had signs and symptoms of dry eye preoperatively. The mean postoperative follow-up duration was 5.7 months (range 3–24 months). The average preoperative tear film height measured by slit lamp using fluorescein staining was 2.5 mm, and on AS-OCT, it was 1212.1 µm. At 3-month postoperative visit, the average Schirmer’s value reduced to 18 mm (P = 0.001), while the TBUT remained similar and not significant statistically (14.2 seconds, P = 0.60). The mean postoperative TFH on slit lamp reduced to 0.26 mm (P < 0.001), and the average TFH on AS-OCT was 776.7 µm (P = 0.035). Fig. 2 shows the pre- and postoperative TFH with fluorescein staining as measured on AS-OCT (3-month postoperative). None of the patients developed dry eye disease in the follow-up period. No intraoperative or postoperative complications were recorded in any patient. Three patients (17.6%) reported no subjective improvement in epiphora (0%) from baseline, while six patients (35.2%) reported excellent response (>75% improvement). Four patients (23.5%) reported 100% satisfaction with the procedure in epiphora reduction. One patient required intraglandular BTA injection 2.5 units transconjunctivally as an additional intervention for persistent epiphora. Table 1 summarizes the clinical data of the study.

Figure 2.

Preoperative and postoperative slit lamp photographs after fluorescein staining showing tear film height (a and b) and AS-OCT of patient 2 (c and d). Pre- and postoperative slit lamp photographs after fluorescein staining showing tear film height (e and f) and ACOCT (g and h) in patient 3 showing increased TFH preoperatively and a decrease in TFH postoperatively at last follow-up visit

Table 1.

Clinical profile of patients in the study

Basic details		Value=n (%)		Mean (SD)		Range		P
Munk score
Baseline     Postoperative 3 months				4 (0) 1.6 (1.07)		0-5 0-5		<0.001
Schirmer’s value
Baseline     Postoperative 3 months				27.8 (6) 18 (9)		(15-35) (4-30)		0.001
Tear film height (slit lamp)
Baseline     Postoperative 3 months				2.5 (0.5) mm 0.26 (0.07) mm		1.8-3 mm 0.1-0.3 mm		<0.001
Tear film height (AS-OCT)
Baseline     Postoperative 3 months				1212.1 (820.9) µm 776.7 (317.9) µm		303-3549 µm 423-1853 µm		0.035
Tear film breakup time
Baseline     Postoperative 3 months				14.6 (3.3) seconds 14.2 (3.6) seconds		8-21 seconds 8-19 seconds		0.60
Subjective epiphora reduction from baseline
Excellent (>75%)     Good (51-75%)     Moderate (26-50%)     Mild (1-25%)     Poor (0%)		6 (35.2%) 3 (17.6%) 4 (23.5%) 1 (5.8%) 3 (17.6%)		-		-

Discussion

The main lacrimal gland has an efferent parasympathetic nerve supply and essentially functions as a reflex secretor.[3,8] It consists of an orbital and palpebral lobe, connected via an isthmus. Partial or complete palpebral lobe dacryoadenectomy was an established surgical treatment for epiphora previously.[9,10] Dry eye disease has been identified as a known complication of palpebral lobe dacryoadenectomy, though the incidence is variable in the literature.[9,10,11,12] Taiara and Smith noted mild xerophthalmia in only one case in a study with 19 patients (5.2%), while Hornblass et al. reported a higher incidence in a study of 37 patients (14%).[10,11] The other complications that have been reported after this procedure include orbital hemorrhage, ptosis, and transient vision loss.[11,13] Intractable dry eye disease following palpebral lobe dacryoadenectomy is also reported in the literature.[9,12] The contribution of each individual lobe toward tear production is unclear; however, as the palpebral portion contains the excretory ducts, any intervention involving the palpebral part carries a potential to cause dry eye disease. POLD is a surgical technique that removes a portion of the orbital lobe, while sparing the isthmus and the palpebral lobe. Schwember et al.[14] reported temporary dry eye symptoms in 2 out of 12 patients, following partial ablation of the orbital lobe. The symptoms subsided 3 months after the procedure, with regular use of lubricating ointment at bedtime. A recent study by Singh and Ali noted that dry eye disease does not occur whether the orbital lobe of the LG is removed partially or completely.[7] Their findings are further supported by the fact that dry eye disease is unusual after dacryoadenectomy performed for LG pleomorphic adenomas.[15]

We excised an approximate 50–60% volume of the orbital lobe of the LG in contrast to a previous study by Singh et al.,[3] where 30–40% of the orbital lobe of LG had been removed. Singh et al.[3] noted that mean tear flow change was statistically nonsignificant at 3-month postoperative follow-up. We increased the excision volume from previously described literature to assess the change at 3 months in our study with a larger amount of gland removal, and at the same trying to preserve around half of the orbital lobe volume. The subjective parameters included in our study were Munk scoring and reduction in epiphora as reported by the patients. The average Munk score reduction indicated an average reduction in the need to dab tears from more than 10 times a day (preoperatively) to less than 2 times after the surgery. Subjective improvement in epiphora was reported by 82.3% patients (n = 14), with more than half of the patients noting a reduction in epiphora by greater than 50% from baseline. Our findings are similar to Singh et al., who noted a subjective improvement in epiphora in 85% patients after POLD surgery. For objective measurement of tear secretion, Singh et al.[3] utilized direct assessment of tear secretion (DATS) from the palpebral lobe. Using a fluorescein strip, DATS was performed to assess the secretory flow rate of the LG. They noted a mean reduction of 29% in the secretory flow rate after POLD at 1 month follow-up visit and 21% reduction from baseline at 3-month visit. We evaluated Schirmer-I value and tear film height measurement (on slit lamp and AS-OCT) as objective measures for epiphora reduction. A mean reduction of 9.8 mm was noted in our study, as opposed to 5.8 mm by Singh et al.[3] Excision of a larger amount of orbital lobe tissue in our study could have contributed to a greater reduction in Schirmer value. This suggests a need for a larger study to titrate the maximum amount of lacrimal gland tissue which can be removed safely to provide the maximum reduction in epiphora and symptomatic relief without causing dry eye symptoms. Schirmer-I is not an ideal parameter in patients with refractory epiphora as the tear meniscus height is already raised. However, reduction in the tear film height pre- and postprocedure provides indirect evidence about the tear secretion and collection in these patients. This change in these values was statistically significant (P < 0.05). A mean reduction of 89% from baseline was noted when tear film height measurement was performed on slit lamp examination (P < 0.05). As this measurement was performed by clinicians in the clinic, it may be prone to observer bias. AS-OCT measurement of the tear film height is a more objective parameter. A mean reduction of 35.9% from baseline was recorded 3 months after POLD surgery in our study (P < 0.05). The objective and subjective reduction in epiphora was not accompanied by any dry eye symptoms or positive fluorescein staining of the cornea. The residual gland left after excision may be able to maintain the reflex tearing function and prevent dry eye disease after POLD. The TBUT values pre- and postsurgery at 3 months were similar in the study, and the change was statistically nonsignificant (P = 0.60).

Singh et al.[3] noted that POLD surgery had similar benefits to intraglandular botulinum toxin injection, at 3-month postprocedure. Both procedures offered temporary relief in epiphora, with gland activity reduction by 20–29%. However, the volume of gland excision was only 30–40% in their study. Excision of a larger amount of the orbital lobe, as in our study, and comparison with botulinum injection may be interesting. Another work by the same authors utilized magnetic resonance imaging (MRI) to conclude that orbital lobe of the LG does not regenerate after excision.[7] Recurrence of epiphora or persistence of epiphora may, thus, be attributable to excessive functioning of the residual glandular tissue or takeover by the accessory lacrimal glands.

The limitations of the current pilot study include a relatively small sample size and the short follow-up duration. Quantifying the amount of the gland removal was based on visual inspection of the gland and not calculated based on image-guided volumetry. MRI or CT-based volumetry studies and their correlation with the amount of gland requiring excision will help develop an algorithm for quantifying the amount of excision. A longer follow-up of this cohort will assist in answering these questions and in assessing the long-term efficacy of this procedure. The strengths of the study include subjective and objective parameter evaluation for assessing efficacy of POLD.

Conclusion

POLD is an effective and safe procedure in patients with refractory epiphora, with symptomatic relief during short-term follow-up. A longer follow-up of these patients will help in understanding the long-term efficacy of this procedure. Further improving the procedure with image-based quantification and customization as per individual patient needs may help standardize the procedure and establish this procedure as an effective solution to refractory epiphora. A refined POLD surgery may potentially benefit patients with refractory epiphora through a one-time procedure as opposed to multiple and repeated needs of intraglandular botulinum toxin injection.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.