A case of simple bilateral dacryops: A review of literature

Purpose: Dacryops, is a clinical entity of unknown aetiology. Here we present the clinical features and radiological presentation of a bilateral dacryops as a unique case. Case Description: A 36year old woman presented with unilateral lid swelling, since 7years non-perceptible but obvious on reflex tear secretion. However, she had no complaints of pain, redness, discharge. On examination, vision was normal and lacrimal ducts were patent. Mass in the left eye was noted on reflex tear secretion such as exposure to air/chewing. No signs of inflammation present. Tear film tests were normal. Fundus, routine blood parameters and serum ACE was negative. Ultrasonography of the orbits showed well defined hypoechoiec cystic lesion along lateral aspect of left globe and CT showed bilateral predominantly cystic lesion more prominent on left compared to right. Bilateral Dacryops, is unusual. Thus it becomes essential that clinicians are aware of this condition and consider it as one of the differential diagnosis of the lacrimal gland masses. Results: A case of bilateral dacryops detected incidentally, was investigated and followed up. Conclusion: Dacryops, or a lacrimal gland ductal cyst, is a rare clinical entity, whose bilateral presentation is unusual. It is essential that we as clinician’s are aware of this condition and consider it as a differential diagnosis of the lacrimal gland masses. © 2020 Published by Innovative Publication. This is an open access article under the CC BY-NC license (https://creativecommons.org/licenses/by-nc/4.0/)


Introduction
Lacrimal apparatus has its own unique anatomy. The tears which are produced by lacrimal gland and accessory lacrimal glands, allows drainage of tears through the lacrimal ducts. The main lacrimal gland is situated in the anterolateral aspect of the orbit and is divided into an orbital part and palpebral part. 1 Dacryops is a rare clinical entity usually affecting the palpebral lobe of the lacrimal gland. It is a rare cystic condition of the lacrimal gland duct of unknown etiology. 2 An history of trauma or inflammation or a congenital anomaly of the excretory duct could be an precipitating factor. 3 Mechanism of spiral valve effect and neuromuscular dysfunction of the duct wall reflects underlying functional problem and intermittent fluctuation of the swelling; 2 It is also said that periductal or conjunctival inflammation may result in lacrimal gland hypersecretion causing damage to the ductile walls and secondary ductile obstruction resulting in formation of the cyst. 3 This rare clinical presentation is usually insidious in onset, presenting as a painless mass on the eye lids. Its bilateral presentation is usually rare.
In our work, we present the clinical features and radiological presentation of a simple.
Dacryops detected bilaterally as a unique case.

Case Study
A 36-year-old female of Indian origin presented to the EYE OPD, with gradual painless swelling of the left upper eyelid for 7 years (Figure 1). There was no history of trauma, inflammation, discharge, epiphora, eye surgery, or systemic illness. The patient mentioned periodic fluctuation in the size of swelling, which increased on crying or chewing. She had no associated pain, redness, discharge or visual disturbances. She denied history of trivial trauma or infection. No similar history in the past or similar complaints in the family members. At present, best corrected visual acuity in both eyes was 6/6 with normal near and colour vision. Ocular fundus was normal and lacrimal syringing was patent in both eyes.
There was a non-tender, fluctuant, tense swelling, and round to oval in shape with smooth consistency on the lateral two-thirds of the upper lid on reflex tear secretion. There was no limitation of extraocular movements, proptosis, or globe dystopia. There was no sign of inflammation, and tear breakup time and Schirmer's test results.
Ultrasonography showed a single-walled cyst in the left eye with low internal reflectivity, without intra orbital extension ( Figure 2). And further computerised tomography (Figures 3 and 4) with contrast enhancement was performed to confirm the diagnosis and cysts were noted bilaterally more obvious on left side.
Routine blood investigations were normal and other investigations to rule out autoimmune disorders were negative. Patient was asymptomatic, denied further management.
She has been kept on followup. Axial and direct coronal CT of orbits with sagittal oblique reformation was performed after administration of a non-ionic contrast material. (Figure 4 ) CT showed a bilateral lateral predominantly cystic lesion more prominent on left side compared to right, contiguous with the palpebral lobe of the lacrimal gland detected on both sides.
Lesion on right side was detected as an incidental finding.
1. Measurement RE 0.5 X 0.7cm LE 1.5 X 2cm 2. Cyst was consistent with fluid density, with peripheral enhancement without nodular or irregular enhancements.
3. Globe and rest of the lacrimal gland tissue was normal 4. No associated tissue inflammation 5. No bony erosions or irregularities seen

Discussion
Lacrimal gland cysts also known as Dacryops. 4-6 usually presents unilaterally, 5 detected on examination Classically a non-tender, well circumscribed, transparent lateral lid swelling along superior temporal aspect of the orbit. Cases exhibiting tenderness and irritation have also been reported. 7 Histologically, these cysts are composed of an inner cuboidal layer containing goblet cells surrounded by an outer myo-epithelial layer with a surrounding glandular tissue and dilated lacrimal gland ducts. 6 Usually slow  growing lesions, can results in proptosis or globe displacement due to mass effect. 7 Contrast-enhanced computerised tomography masses with fluid density in the region of the lacrimal glands, lateral to the globe with no bony abnormality is detected. 8,9 Although there are no CT attenuation values specific for dacryops, the literature has reported fluid and softtissuedensities in relation to these swelling. 3,6 In our patient, CT examination (field of view, 15 cm; 120 kVp; 230 mA; 1.3-mm slice thickness; matrix, 512 * 512; axial and direct coronal imaging with sagittal reformations) showed bilateral fluid-density masses located in the palpebral lobe of the lacrimal glands. No evidence of bone erosion or adjacent inflammation was detected (Figures 3 and 4). Although the patient complained of the swelling on left side, lesion was detected on right side ( Figure 2) incidentally on radiological examination.
Cysts involving the orbital part of lacrimal gland are rare. Because of the bilateral incidence of the cysts, it is vital to rule out systemic disease such as Sjogren's syndrome, mikulicz disease, sarcodosis. 10 As they result in nonspecific diffuse enlargement of the cysts. Other differential diagnosis to be considered are benign and malign orbital tumours such as pleomorphic adenoma, adenoid cystic carcinoma, mucoepidermoid carcinoma, pleomorphic adenocarcinoma, lymphoma, pseudo lymphoma, and metastasis and developmental cysts such as dermoid and epidermoid cysts must be considered.
Overall, the diagnosis depends on biopsy results and the patient's clinical history. In our patient, the bilaterality of the lesion, fluid attenuation of the lesions, lack of internal enhancement, and absent inflammation serves as an evidence for this condition. Therefore, other possibilities were considered such as dacryops because of its classic location in the orbit and presentation.
Although the treatment for symptomatic dacryops involves local resection through a superotemporal conjunctival approach without damaging the remaining tear ducts. Use of topical antibiotic/steroid ointment has also been described.Marsupalisation can be performed to fistulise the cyst onto the conjunctival surface. Some authors have used blue-green argon laser to open and fistulise the cyst. 11 Smaller cysts that are asymptomatic can be observed as in our report.
In summary, dacryops, or a lacrimal gland ductal cyst, is a rare clinical entity. It is essential that we as clinician's are aware of this condition and consider it as a differential diagnosis of the lacrimal gland masses.

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Conflict of Interest
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