Subretinal Biopsy

The most common condition in which transvitreal biopsy1 is performed is a subretinal mass in the posterior pole; the surgeon is not sure from the appearance of the lesion whether he is faced with a tumor or, for example, an old hemorrhage.

•Complete the vitrectomy (especially, create a PVD).

•Carefully choose the retinotomy site, which should be over the lesion, as far from the major vessels as possible.

•Consider performing a light diathermy.2

Pearl

The mass may be a vascular tumor; having the endodiathermy probe available in case of a subretinal bleeding following the taking of the sample is advisable.

•Remove a small piece of the mass with forceps3 or via aspiration into a 23 g flute needle.4

–In general, the use of the probe is less favorable as the material may get damaged. If the probe needs to be employed, the aspiration should be done by a nurse using a syringe attached to the tubing of the probe. This avoids diluting the material.

•Typically, it is not necessary to perform a F-A-X. The retinotomy need not be lasered.5

1Only biopsy done intraoperatively is discussed here.

2Without diathermy, there is always a chance, however small, for bleeding.

3Harder mass may require the use of scissors.

4The yield is a much larger sample than with the nonsurgical “fine-needle aspiration” technique.

5Because of the mass underneath, such laser would be ineffective anyway.

F. Kuhn, Vitreoretinal Surgery: Strategies and Tactics,

DOI 10.1007/978-3-319-19479-0_37