Pain After Intraocular Injections

The most likely cause of pain after an injection is a corneal abrasion. This can result from rubbing the lid speculum over the cornea during its insertion. Doctors should lift the lids as they place the speculum. The metal speculum will rub on the conjunctiva beneath the lids but that usually causes only a mild and transient irritation. Cornea abrasions typically will heal within a few days but are extremely painful. Rarely they can become infected. Most physicians place their patients on topical antibiotics after the injection so that will reduce the risk of infection.

The other most likely cause of pain is dry eye and chemical irritation from the many anesthetic and antibiotic drops and Betadine that are used during the injection process. This usually occurs in patients who have had dry eye symptoms before. In patients with previous symptoms of dry eye, it would be best to routinely start artificial tears after the injection. In severe cases, it’s best to use artificial tears without preservatives.

Lucentis can cause intraocular inflammation but it’s uncommon, usually very mild, and therefore probably often not responsible for pain.

If pain persists for more than a day, the patient should check with their doctor. If pain is accompanied by reduced vision that could mean an intraocular infection, (endophthalmitis), and the patient should call the doctor immediately.

related posts:

Pain from Intraocular Injections (February 2007)

Pain After Avastin Injections (May 2006)

Pain with Intraocular Injections (November 2006)

Pain from Intraocular Injections

Some patients (or their daughters) have written to tell me that they had severe pain either during or after an intraocular injection. The pain was severe enough to dissuade the person with AMD from having another injection. Usually injections are relatively pain free and the patient has no or mild discomfort afterwards. Many people will have a small area of subconjunctival hemorrhage that looks fiery red in the area of injection. This hemorrhage however should not cause pain and doesn’t cause any problem.

Some doctors use Lidocaine gel as their only anesthetic. The nurse squirts a wad of jelly on the conjunctiva in the area of injection and leaves it there under the lid for five to ten minutes. I found that the jelly worked very well in about three out of four patients. About a quarter of the patients still have significant pain as the needle penetrates the eye. For that reason, I still inject Lidocaine beneath the conjunctiva. I then wait at least five minutes before giving the intraocular injection. This works well about ninety percent of the time and the remaining ten percent have only mild pain.

Some of the causes for pain during the injection could be:

1. The doctor uses only topical anesthetic drops or Lidocaine gel.
2. The doctor doesn’t wait long enough for the anesthetic to take effect.
3. The patient feels the dryness from the eye being kept open for two long.
4. The patient has irritation of the conjunctiva from the Betadine prep.
5. The needle isn’t sharp.

This is what I do to try to eliminate the pain:

1. I wait at least five minutes after the subconjunctival injection. If I’m busy, I may go see another patient and then come back. If I’m not, I complete all the paperwork and talk with the nurse or patient until five minutes has elapsed.

2. After I draw up the Lucentis with the large bore needle, I put the 30 gauge needle on the syringe. I don’t take off the cap of the thirty gauge needle to push up the plunger to get the right dose. Taking the cap off and then putting it back on can blunt the needle or even cause a little burr at its end. I then have to push the needle harder to get it to pierce the sclera and the patient feels pain.

3. I don’t put the lid speculum in until I’m ready to give the injection. That means I’ve already drawn up the Lucentis or have the Avastin ready. I’ve set the calipers for the right distance. I put on the drape, insert the speculum, and place a drop of Betadine at the injection site. Then I take the cap off the 30 gauge needle for the first time, push up the plunger to .05, inject, and then remove the speculum. The speculum should be in place only about sixty seconds.

4. Just before the injection, I tell the patient that he or she may feel a little pinch but that it will last for a second or less. That way they aren’t surprised if they do feel something and aren’t too concerned.

5. The nurse irrigates any excess Betadine from the eye right after the injection.

6. After the injection, I ask patients if they can see my hand as I wave it in front of their eye but I don’t check the IOP. I don’t think there has ever been an artery occlusion after a 0.05ml injection. Repeated IOP checks may cause a corneal abrasion.

related posts:
Pain After Avastin Injection (May 2006)
Pain with Intraocular Injections (November 2006)
Pain After Intraocular Injections (February 2007)

Treatment Trends for Neovascular AMD 2003-2006

It’s interesting to review the treatment trends for neovascular AMD over the last four years. Below are tables of the various treatments performed in our main vitreoretinal clinic at the University of Iowa. PDT was king in 2003 and 2004. Macugen and PDT were used about equally in 2005. Avastin took over in late 2005. Avastin and Lucentis dominated in 2006. The number of Lucentis injections is increasing but Avastin is holding fairly steady. The PDTs done later in 2006 were often used in combination with Avastin or Lucentis.

Total 2003
PDT	327

Total 2004
PDT	390

Total 2005
PDT	330
Avastin	104
Macugen	296

2006	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Total 2006
Avastin	56	59	74	93	95	103	68	92	88	76	82	73	959
Kenalog	-	-	-	-	-	-	1	13	10	6	3	3	36
Lucentis	-	-	-	-	-	-	39	96	98	111	94	113	551
Macugen	26	14	14	12	11	2	3	5	4	3	2	2	98
PDT	18	14	7	-	4	7	3	2	1	3	6	9	74