What is the lacrimal syringing test?
Syringing is a procedure for testing the patency of the lacrimal drainage system. Normal saline (NS) is injected into the nasolacrimal drainage system through the upper or lower punctum and patency will check.
Why is Syringing Done?
It is done for diagnostic and therapeutic purposes. It is done inpatient with the complaint of watering.
Indications of Lacrimal Syringing:
- In epiphora (obstruction of the lacrimal drainage system. The tear spills over the lower eyelid margin onto the cheek)
- In chronic conjunctivitis not responding to the treatment.
- Sometimes syringing is done before the intraocular surgery e. g. in cataract and glaucoma surgery to rule out any blockage and infections on the lacrimal apparatus.
Instruments required for Syringing Procedure
- Large steel tray or kidney tray.
- Lacrimal cannula
- Punctum dilator
- Eye towel
- Cotton swab
- Binocular Loupe
Medicine required for the syringing procedure
- 4% Lignocaine (Xylocaine) or proparacaine hydrochloride ophthalmic solution (Aurocaine) 0.5% for topical use.
- Normal saline
- Antibiotic eye drops
Remember: before doing any syringing you must know the anatomy of the lacrimal drainage system
How to do syringing? Procedures of lacrimal syringing:
- Explain to the patient, what you are going to do.
- Make the patient comfortable in bed.
- Wash your hands.
- Put two drops of 4% xylocaine drops into the eye.
- If you want, ask your colleague to fix a binocular loupe for you.
- Draw 2ml of normal saline into the syringe and fix the lacrimal cannula in the syringe.
- Dilate the lower punctum with the punctum dilator. (The punctum dilator should be inserted first vertically for about 1mm then horizontally according to the direction of the lacrimal canaliculus).
- First, insert the cannula in the lower punctum vertically down 1-2mm then horizontally towards the nasal side. (The punctum is about 0.3 to 0.5 mm in diameter.)
- Give the patient antibiotic eye drops at the end of the procedure.
Lacrimal Syringing Results
In Normal Cases, Fluid flows back freely from the patient`s nasolacrimal duct in the throat. Tell the patient that the fluid can be swallowed.
Same Canalaculi Block
There is the regurgitation of a clear fluid from the same punctum. (block at the canaliculus)
Common Canaliclus Block
There is regurgitation from the upper and lower punctum. The fluid is clear that comes out quickly (block at the common canaliculus)
Naso Lacrimal Duct Obstruction
Fluid mixed with mucopurulent substance from the upper and lower punctum (block at the nasolacrimal duct.)
If there is the regurgitation of the fluid, the procedure is repeated 3-4 times. If the block does not open surgery should be advised.
To differentiate between the common canaliculus obstruction and the nasolacrimal duct obstruction probing is done with the help of the Bowman probe. Soft stop indicates common canaliculus obstruction and hard stop indicated naso lacrimal duct obstruction.
- Acute dacryocystitis
- Other acute infection in the eye e.g. Acute conjunctivitis.
In small children, it can be done under general anaesthesia with intubation with the endotracheal tube.
The complication of Lacrimal Syringing
- Iatrogenic infection
- Creation of false passage.
What is the ROPLAS test?
ROPLAS denotes Regurgitation on pressure over the lacrimal sac. It is a clinical test that helps in diagnosing nasolacrimal duct obstruction (NLDO) with specificity as high as 99%. This means that if the ROPLAS test is positive it mostly confirms that the patient has a nasolacrimal duct obstruction (NLDO).
ROPLAS (Photo Source: https://entokey.com/evaluation-of-epiphora/)