Serkan Ünlü

Serkan Ünlü investigates cardiac imaging and the dependence of measured heart function on image acquisition. His official institutional profile identifies cardiology as his unit and lists cardiac and cardiovascular research areas.^[ref]

Ünlü is first author of a primary study testing cardiac image foreshortening in echocardiography. The investigators imaged 72 participants using a GE Vivid E9 system and deliberately collected altered apical views from a window one rib-space above the optimal position. They compared ejection fraction and longitudinal deformation measurements using two analysis systems.^[ref] This is an experimental acquisition comparison: the view changes while the patient's chamber is not assumed to have become anatomically shorter.

An original geometric example shows why a constant scale error and a phase-dependent distortion have different consequences. Let a modeled chamber length change from $L_d=10$ to $L_s=8$ cm. Its fractional shortening isMultiplying both lengths by 0.9 leaves the ratio unchanged. If instead the measured lengths become 9 and 7 cm because the same 1 cm terminal segment is missed in each phase, the apparent fractional shortening is $-2/9\approx -0.222$. Neither model is a complete echocardiography reconstruction; they demonstrate why the error mechanism matters even in a normalized measurement.

The primary study found that deliberately foreshortened views changed measured deformation, with the effect differing by myocardial layer and analysis system.^[ref] Ünlü's documented contribution is to test that dependence experimentally. Repeatable software output does not establish that the acquired image represents the intended anatomical view.