During my first week in my new practice, I received a phone call from an elderly woman looking for some advice.  She had noticed a “blister” on her eye that was not affecting her vision and wasn’t painful.  She was sufficiently worried about it to call NHS 24 who advised her (as they tend to do) to either go to A&E or visit her GP.  So, she went to her GP.  He took one look at it and said, “Don’t worry” and gave her some Viscotears gel.  She had been under the impression that it would disappear if she used the Viscotears but it was still there a few days later.  The patient called her GP again who, this time, advised her to see an optometrist.

Obviously this is where I come in.

So, she’s on the phone, telling me the timeline from noticing the blister until today.  She’s calling for a second opinion.  I confirmed with her that it was still painless and not affecting vision.  I told her that it sounded like a retention cyst (side note: I’ve heard these things called inclusion cysts as well – is there a difference?).  Anyway, I told her that she was quite right, it was a kind of blister – it’s caused by fluid gathering under the conjunctiva.  If it was bothering her, I said I could use a sterile needle to make a small hole in it and drain some or all of the fluid, reducing its size.  She really didn’t like the sound of that, even though I told her it was both painless and something I’ve done several times before.  She decided she wanted a third opinion (sigh) and rang off.

I noted the advice I’d given on her record card and filed it away.

Fast forward a week and I’m looking at my clinic for the day.  I notice this same lady is booked in for a supplementary eye test.  I realise immediately that she’s decided to come in to have the cyst drained but there’s a problem: in my old practice, we had a locker full of sterile needles and assorted medicines we were able to use and dispense as part of the Lanarkshire Eye Network Scheme (LENS).  I’m no longer in Lanarkshire so I was without my bag of tricks.

I had a gap in my clinic so I googled where to get sterile needles and it just happens that one of the pharmacies nearby stocked them.  After finding out that they are free (you just have to go in and ask for them*), I asked one of the girls to pop along and bring back some 25 or 27 gauge needles.  She brought back a small selection so I was ready for my patient when she appeared.

The patient was a lady in her seventies.  She seemed a little nervous.  I had a quick look on the slit lamp to confirm that the blister was indeed a retention cyst, and explained that I would pop a drop of anaesthetic in that eye (this would be the worst part of it as OXB 0.4 is a bit nippy) then I would ask her to look as far to the right as possible (the cyst was in her right eye, nasal to the cornea).  While she was looking over to the right, I would use a sterile needle to make a small hole in the blister then I would gently press against the cyst to squeeze some of the fluid out.

She wouldn’t feel anything but it was very important for her to keep looking over to the right.

So, I opened up one of my fresh-from-the-pharmacy needles, using the little plastic sheath that it came in to put a bend in it about 2/3 of the way from the tip.  By bending the needle into a 90-120 degree angle, you are then approaching the eye with the tip perpendicular to the eye, which is safer.  This is also the way I position my needle when removing corneal foreign bodies.

I’ve drawn a little diagram below to illustrate:

Hopefully, my drawing and penmanship skills are good enough so that you get the idea.

It is worth warning your patients that there may be a little blood as you are bound to nick one or two of the fine blood vessels in the conjunctiva.  Don’t worry about this as they close up pretty quickly.  If there is a lot of blood then, you know, you should panic a bit and perhaps call the hospital**.

So, back to my patient: I popped in the OXB 0.4, got her comfortable on the slit lamp (very important as you want your patient to be as still as possible with their head flush against the head bar and chin on the chin rest).  As with Volk, you can rest your bent arm on the table (or something else that’s stable) to give you extra control over the needle.  Once you are good to go, focus a wide beam on the cyst with the slit lamp at a low magnification (I find 10x is perfect for this) and ask the patient to look over to the side which exposes as much of the cyst as possible.  You will always come in from the closest canthus so you are nowhere near the cornea with the needle.  I was approaching nasally in this case.

The first time you do this, you will noticed that it takes a firm pressure to push the needle into the cyst.  Again, you are doing this from the side.  Some cysts have internal sections so you may have to pierce the internal walls several times to release all the fluid.

In the case of this patient, one poke was enough.  I used the bend of the needle to squeeze the cyst and it immediately started deflating.  There was a little bit of pink in the fluid as I had nicked a very fine blood vessel.  The result was instant and pretty impressive.

I asked the patient to blink a few times and be careful not to rub her eyes while I hunted around for a mirror.  She was astonished when I showed her that the cyst was gone.  She’d felt nothing during the (very fast) procedure and I’d solved a problem that had been annoying her for over a week.  In short, she thought I was magic.

Anyway, it’s recommended that you pop in one drop of chloramphenicol 0.5% after the procedure (just in case).  You should also remember to remind the patient that they should avoid rubbing or touching their eye for the next 30 mins or so because of the anaesthetic effect.  If you have one of the College’s tear off anaesthetic leaflets then also give them this before they leave.

The cysts seem to be more common in patients with dry eyes so if they ask you what can be done to stop the cyst forming again, you can advise ocular lubricants like hypromellose or carbomer gel (both should be available either on minor ailments schemes for low income patients, children and pensioners or on repeat prescription from their GP).

I should also say that I’ve been on two training courses on corneal foreign body removal.  I’ve also worked with two amazing optoms who were on hand to talk me through eyelash epilation, lancing retention cysts and removal of concretions.  We should always work within our own sphere of competence but remember that confidence and competence comes from actually doing these things.  If you feel this is something you would like to be able to do in practice, ask a colleague to teach you or go on a course that covers the skills.  Your patients will thank you!


* This is, in part, so that intravenous drug users don’t share needles.  I later went into the pharmacy to introduce myself and to tell the pharmacist that I’m happy to see any patients with eye related issues who may come to them for advice.

** Just joking: if you are careful and follow this technique, you shouldn’t have any problems.