Iris Tumor / Nevus / Cyst
Infrared video can be very helpful in differentiating iris nevi vs tumor vs cyst.
If video fails to load, use this link: Cysts-tumors Transillumination
Iris cysts can look dark on slitlamp exam but usually light up on transillumination due to the fluid in the cyst.
Nevi do not extend beyond what you see and sometimes they are on the posterior iris and not visible from a front slitlamp exam. Often times an iris tumor will have extension into the sclera.
| room light | transilluminated | |
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| Slit lamp | IR transillumination | Gonioscopy |
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