Fig. 7.5 In a tractive diabetic retinopathy, it is wise to stain the membranes with trypan blue. The membranes can be grasped with the Eckardt forceps and delaminated with the knob spatula

hold the knob spatula for about 1 min onto the bleeding source (1 min is longer than you think) or – what we prefer – to bimanually aspirate the source of bleeding with the fluid needle and cauterize it. The tractional membranes are dissected and removed through a constant change of instruments between delamination and cauterization.

Pits & Pearls No. 44

Diabetes and anti-VEGF: A major problem during the surgery of diabetic retinopathy is multiple bleedings from the proliferations. You can already create preoperatively a much more favourable starting point through the intravitreal injection of a VEGF inhibitor 1 week before the PPV. The PPV runs then a lot more pleasantly, since the intraocular haemorrhages are much less and the dissection of fibrovascular tractional membranes is facilitated. Caution: A tractive detachment might become worse after injection of a VEGF inhibitor. The patients at risk for this sever complication are typically insulin-dependant patients with annual fibrosis at the posterior pole and little to no PRP.

Pits & Pearls No. 45

Diabetes and cataract: If you have an opacified lens, then also perform a cataract operation before the vitrectomy. Especially in advanced diabetic retinopathy cases, you avoid anterior segment inflammation with posterior synechiae. A diabetic eye, which is pre-treated with anti-VEGF and cataract surgery, is much easier to vitrectomize.

Lens-sparing vitrectomy: We experienced good results with PPV and SF6 in young diabetic patients. Even after 10–20 years, the lens hardly opacifies.

110 7 Diabetic Retinopathy

Pits & Pearls No. 46

Diabetes and intraoperative haemorrhage

Slight bleeding: (1) Increase the intraocular pressure to approximately 40 mmHg. (2) Aspirate the blood with the fluid needle and cauterize bimanually the bleeding source with endodiathermy (or laser therapy).

Moderate bleeding and bleeding at the optic disc: Compress the source of bleeding 1 min with the knob spatula.

Severe bleeding: If the bleeding is so severe that there is no view, and despite aspiration with the fluid needle it does not clear up, then you should perform a fluid–air exchange. The bleeding will stop. Try now to cauterize the bleeding source with endodiathermy or compress it mechanically with the knob spatula.

a

b

Fig. 7.6 (a) These extensive membranes of a 24 year old patient are best removed with bimanual technique. (b) The membrane can be grasped with a fluid needle or a forceps and the adhesions are removed with a blunt instrument and straight scissors

b

5. Apply PRP

If you created iatrogenic tears with lifted edges during removal of the tractional membranes, you must, if the peeling is finished, instill PFCL and laser treat these breaks. In addition, a PRP should be performed. By using the scleral depressor, you can laser treat up to the ora serrata.

After endolaser coagulation, check if a new bleeding occurred at the central pole and treat it before you move on to the tamponade.

6. Tamponade

In most cases, we use air or 20% SF6 and sometimes 12% C3F8 or 1,000 cSt silicone oil. Use silicone oil in difficult cases (Fig. 7.7).

7. Removing the trocars

The trocars are removed as described in ‘Special Techniques of PPV’ section. If silicone oil is used, one should suture the sclerotomies, otherwise oil might translocate under the conjunctiva.