Question

A 60 year old man presented with watering from his left eye since one year. Syringing revealed a patent drainage system. Rest of the ocular examination was normal. A provisional diagnosis of lacrimal pump failure was made. Confirmation of this diagnosis would be:

• A. Dacryoscintigraphy
• B. Dacryocystography
• C. Pressure syringing
• D. Canaliculus irrigation test

Hint:

Patent syringing rules out a block, so the next test must check tear pump function, not anatomy.

Answer 1

The Correct Option is A

The key here is telling apart a blocked drainage channel from a channel that is open but not pumping tears well.

1. Dacryoscintigraphy: Places a tiny radioactive tracer on the eye and tracks it into the nose with a gamma camera during normal blinking. It measures the actual pumping action of the eyelids on the tear sac, which is exactly what needs checking when the channel is already open. This is the confirmatory test.
2. Dacryocystography: Uses dye and X-rays to outline the shape of the drainage channel. It is an anatomical test, and this patient's channel is already known to be open from syringing.
3. Pressure syringing: Still just forces fluid through under pressure, so it repeats what the first syringing already proved and adds nothing about how the tears drain during normal blinking.
4. Canaliculus irrigation test: Again checks whether fluid passes through the canaliculus under pressure, an anatomical patency test, not a functional one.

Because the drainage system is already open, the diagnosis rests on showing that tears fail to move through it under ordinary conditions, and dacryoscintigraphy is built to show exactly that.

Let's summarize:

• Syringing and irrigation tests check anatomy under artificial pressure.
• Dacryoscintigraphy checks physiology, how well the pump moves tears naturally.

So dacryoscintigraphy is the test that confirms lacrimal pump failure.