Oto-Encoder Ağı ile Ultrason Görüntülerinin Yatay (Lateral) Çözünürlüğünün Artırılması

Öz

Ultrason görüntüleme, tıbbi tanı amaçlı yaygın olarak kullanılan bir yöntemdir; ancak çözünürlüğü, dalga boyu, odak uzaklığı, tarama çizgisi yoğunluğu ve kare hızı gibi etkenlerle sınırlıdır. Yatay (lateral) ve zamansal çözünürlük arasında temel bir ödünleşim bulunmaktadır; tarama çizgisi yoğunluğunun artırılması, mekânsal ayrıntıyı artırırken kare hızını düşürür. Bu çalışma, zamansal çözünürlükten ödün vermeden yatay çözünürlüğü artırmak amacıyla derin öğrenme temelli, özellikle de Oto-Encoder tabanlı bir yaklaşımın potansiyelini araştırmaktadır. Oto-Encoder’ın başarımı; en yakın komşu, lineer ve spline enterpolasyon gibi geleneksel enterpolasyon yöntemlerine karşı yapısal benzerlik (SSIM), tepe sinyal-gürültü oranı (PSNR), çok ölçekli SSIM (MS-SSIM) ve özellik benzerliği (FSIM) metrikleriyle değerlendirilmiştir. Sonuçlar, Oto-Encoder’ın en yüksek SSIM ve FSIM değerlerini elde ederek yapısal bütünlüğü ve özellik korunumunu en iyi şekilde sağladığını göstermektedir. Ayrıca, RF sinyal analizi, Oto-Encoder’ın genel dalga formunu koruduğunu, ancak küçük genlik ve faz sapmalarının mevcut olduğunu ortaya koymaktadır. Bu bulgular, derin öğrenme tabanlı süper çözünürlük yaklaşımlarının, geleneksel çözünürlük ödünleşimlerini en aza indirerek yatay çözünürlüğü etkili bir şekilde artırabileceğini göstermektedir.

Anahtar Kelimeler

• Ultrason Görüntüleme
• Çözünürlük Artırımı
• Yatay (Lateral) Çözünürlük
• Derin Öğrenme
• Enterpolasyon

Lateral Resolution Enhancement of Ultrasound Images via Auto-Encoder Network

Öz

Ultrasound imaging is widely used for medical diagnostics, but its resolution is inherently constrained by factors such as wavelength, focal length, scan line density, and frame rate. A fundamental trade-off exists between lateral and temporal resolution, where increasing scan line density enhances spatial detail at the expense of reduced frame rates. This study explores the potential of deep learning, specifically an AutoEncoder-based approach, to enhance lateral resolution without sacrificing temporal resolution. The performance of the AutoEncoder is evaluated against traditional interpolation methods, including nearest, linear, and spline interpolation, using structural similarity (SSIM), peak signal-to-noise ratio (PSNR), multi-scale SSIM (MS-SSIM), and feature similarity (FSIM) metrics. The results demonstrate that the AutoEncoder outperforms interpolation methods, achieving the highest SSIM and FSIM, indicating superior structural preservation and feature retention. Additionally, the RF signal analysis shows that while the AutoEncoder maintains the overall waveform structure, minor amplitude and phase deviations exist. These findings suggest that deep learning-based super-resolution can effectively enhance lateral resolution while minimizing traditional resolution trade-offs.

Anahtar Kelimeler

• Ultrasound Imaging
• Resolution Enhancement
• lateral resolution
• Deep Learning
• Interpolation.

Kaynakça

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