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DVD
Video 13 Endophthalmitis
The Endophthalmitis Vitrectomy Study recommends intravitreal antibiotics if the visual acuity is greater than hand motion and PPV if visual acuity is equal to light perception [1]. In practice, most colleagues tend to perform a vitrectomy at earlier stages with a better visual acuity. In every tertiary vitreoretinal centre, clear treatment guidelines should be established; all necessary antibiotics and an examination of the microbiological specimens should be available at all times.
In recent years, there is a signiÞcant increase of endophthalmitis in patients following intravitreal injections of anti-VEGF agents. In contrast to the previously more common endophthalmitis following cataract surgery, the majority of these patients are still phakic, and the lens or opaciÞed vitreous adjacent to the lens might impair the view of the posterior segment for vitrectomy. If you perform a phaco, then open the posterior capsule and do not insert an IOL in order to improve the outßow of aqueous and reduce bacterial growth in the capsular bag.
If you are contacted from a peripheral institution regarding a patient with presumed endophthalmitis and a delay of several hours before the patient can be seen in your institution is to be expected, it is advisable to ask the referring ophthalmologist to perform an intravitreal injection of antibiotics before sending the patient. Time is of paramount importance in treating endophthalmitis, and the beneÞt of earlier antibiotic injection overrides the disadvantages of a short delay in the referral and possibly the failure to obtain a specimen for microbiology.
Preparation of antibiotic therapy (according to the guidelines of the EVRS)
1 mg/0.1 cc Vancomycin and
2.25 mg/0.1 cc Ceftazidime (Fortum)
U. Spandau, H. Heimann, Practical Handbook for Small-Gauge Vitrectomy, |
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DOI 10.1007/ 978-3-642-23294-7_9, © Springer-Verlag Berlin Heidelberg 2012 |
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You need: 1× Vancomycin 500 mg and 2× plastic ampoules 10 ml NaCl 9 mg/ml (9%)
Vancomycin
1. Dissolve 500 mg of Vancomycin in 10 cc NaCl 9 mg/ml (Þrst ampoule). 2. Aspirate 2 cc of the second NaCl 9 mg/ml ampoule and discard it.
3.Add 2 cc of the dissolved Vancomycin (Þrst ampoule) into 8 cc of NaCl 9 mg/ml (second ampoule). The ampoule contains now 10 cc of Vancomycin 10 mg/ml.
4. Inject 0.1 cc (=1 mg) Vancomycin into the vitreous cavity. (Remark: cc = ml)
You need: 1× Fortum 500 mg and 2× plastic ampoules 10 ml NaCl 9 mg/ml (9%)
Ceftazidime
1. Dissolve 500 mg of Fortum in 10 cc NaCl 9 mg/ml (Þrst ampoule).
2. Aspirate 8.8 cc of the second NaCl 9 mg/ml ampoule and discard it. The second ampoule contains now 1.2 cc NaCl 9 mg/ml.
3. Draw 1 cc of the dissolved Fortum and inject it into the second ampoule. The second ampoule contains now 2.2 cc Fortum 22.7 mg/ml.
4. Inject 0.1 cc (=2.27 mg) Fortum into the vitreous cavity.
Instruments
1.3-port or 4-port trocar
2.Insulin syringe for sampling
Potential tamponade
Silicone oil
Individual steps
1.3-port or 4-port system
2.Specimen from the anterior chamber
3a. Pseudophakic eye: Flushing of the anterior chamber and the capsular bag 3b. Phakic eye: Phaco
4.Specimen from the vitreous cavity
5.Vitrectomy
6.If possible, induction of posterior vitreous detachment
7.Intravitreal antibiotics
8.Tamponade with silicone oil
1. 3-port system
You can use a 3-port or a 4-port trocar system.
2. Specimen from the anterior chamber
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Fig. 9.1 Fibrin and pus in an anterior chamber of an eye
with endophthalmitis. Perform an anterior chamber tap
3a. Pseudophakic eye: Flushing of the anterior chamber and the capsular bag
After performing a paracentesis, perform an anterior chamber tap (Fig. 9.1). Then rinse the anterior chamber and the capsular bag thoroughly with BSS and irrigation/ aspiration (I/A). With foudroyant endophthalmitis, it is appropriate to explant the IOL with the capsular bag.
3b. Phakic eye: Phaco
Perform a phaco and cut a round hole in the posterior capsule with the vitreous cutter from pars plana.
Pits & Pearls No. 48
Fibrin in the anterior chamber can be extracted easily with Eckardt forceps via a paracentesis.
4. Specimen from the vitreous cavity
Take a sample from the central vitreous with an insulin syringe. You can either connect the syringe to the vitreous cutter or aspirate manually (dry vitrectomy) or you can send the vitrectomy cassette to microbiology.
Pits & Pearls
Microbiology: The time period between obtaining the specimen and processing in the microbiology laboratory is extremely important. The longer this time period, the less likely it is to identify the causative pathogen. Therefore, good communication between the ophthalmologist and the microbiologist is
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essential. As patients with endophthalmitis are often treated out of normal working hours, a clear protocol for obtaining and processing the specimen (whom to contact, how to send the specimen, where to send the specimen, etc.) is essential.
5. Vitrectomy
Follow the usual steps of vitrectomy. Be very careful not to induce iatrogenic retinal breaks, as these will necessitate a silicone oil tamponade in endophthalmitis cases.
In cases of severe endophthalmitis, it is sometimes impossible to identify all structures correctly. It is therefore very easy to cut through the retina. In such cases, work your way very carefully from Òtop to bottomÓ, e.g. from the space behind the lens to the posterior pole. Try to identify retinal vessels in order to identify the correct working plane. If you are unsure and you only see a yellowish mass behind the lens, start cutting in the periphery Ð the retina might be detached and pulled anteriorly; it is then better to cut through the peripheral retina. Focus on identifying retinal vessels as your guideline as early as possible.
Pits & Pearls
Do not open the pars plana infusion without visualizing it Þrst (see Chap. 4). If you are unable to see the internal opening of the infusions port, start the vitrectomy using an infusion via an anterior chamber maintainer.
6. If possible, induction of posterior vitreous detachment
Next, a vitrectomy is performed (Fig. 9.2). The retina often shows panretinal haemorrhages and epiretinal pus (Fig. 9.3). You should try to perform a posterior vitreous detachment so that as much vitreous as possible is removed. The bacteria then have poorer growing conditions.
Caution: The retina in endophthalmitis is very fragile. It is easy to induce breaks.
7. Intravitreal antibiotics
Now Vancomycin and Ceftazidime are injected into the eye.
8. Potential tamponade: Silicone oil
Some surgeons suggest silicone oil as tamponade because it is attributed with bacteriostatic properties. Others use no tamponade. In the latter, one has no or only a reduced view of the fundus during the Þrst postoperative days, after about 3 days, the eye will clear up. If you have identiÞed or created a retinal break, we recommend silicone oil tamponade. The antibiotics can be injected into the anterior chamber or into the silicone oil. There is no place for a gas tamponade in endophthalmitis cases.