The Erdey Searcy Eye Group has the distinction of being one of the few practices in Ohio that has acquired Ultrasonic Biomicroscopy (UBM) technology! High Frequency Ultrasound imaging of the eye is an essential tool in a demanding Ophthalmology facility.
Direct Sulcus to Sulcus measurement 11.7mm
One very important application of this technology is in our busy Implantable Contact Lens ( EVO Visian ICL™) practice. The UBM is used to acquire an actual image and measurement of the length of the eye’s ciliary sulcus, the length of the space the EVO Visian ICL will occupy once implanted. Knowing the actual sulcus to sulcus measurement allows the surgeon to better select the length of the Visian ICL that should be used to achieve a proper ICL vault. This is like knowing a shoe’s size before putting your foot in it. If you only had an estimate of the shoe’s size, you might find it to be too small (or large) once you slipped your foot in it. If the cilary sulcus diameter is underestimated, the implanted ICL may be too long for that eye and may need to be removed. Thankfully, this is an uncommon occurrence, even using the established measuring method (calipers), however it is our goal to reduce this potential problem to near zero in our practice. The established measuring method makes an assumption that the ciliary sulcus diameter is proportional to a measurement taken on the outside of the eye of the cornea (limbus to limbus diameter). A study using limbus to limbus measurement vs. VuMax II UBM imaging found 34% of eyes would have received a different size ICL if UBM had been used! At the Erdey Searcy Eye Group, all EVO Visian ICL patients have their eye modeled with UBM as part of their pre-operative evaluation.
Ideal ICL vault
Oversized ICL - note anterior displacement of the iris
Over the last decade, Dr. Erdey has studied the use of UBM in measuring natural lens diameter in anticipation of cataract extraction and intraocular lens implantation surgery. He has determined that obtaining this important measurement will better predict if a Crystalens® Intraocular lens will adequately "fit" once implanted. Obtaining pre-operative UBM measurement of the natural lens equator diameter allows us to better “filter out” eyes which are too short for this particular IOL design and in those cases, we choose a “one size fits all” IOL design. We have nearly eliminated "U" or "Z" syndromes with the use of Crystalens/Trulign IOL since using UBM as a screening tool.
Lens equator 9.31mm – adequate for Crystalens/Trulign 11.5mm dia.
Lens equator 8.4mm: too short – avoid crystalens/trulign
Lens equator 9.7mm: can use 11.5mm Crystalens/Trulign or larger 12.0mm Crystalens