IEEE Trans Med Imaging. 2014 Jun;33(6):1304-12. doi: 10.1109/TMI.2014.2309440. Epub 2014 Mar 3.
Laser photocoagulation is currently the standard treatment for sight-threatening diseases worldwide, namely diabetic retinopathy and retinal vein occlusions. The slit lamp biomicroscope is the most commonly used device for this procedure, specially for the treatment of the eye periphery. However, only a small portion of the retina can be visualized through the biomicroscope, complicating the task of localizing and identifying surgical targets, increasing treatment duration and patient discomfort. In order to assist surgeons, we propose a method for creating intraoperative retina maps for view expansion using a slit-lamp device. Based on the mosaicking method described by Richa et al, 2012, the proposed method is a combination of direct and feature-based methods, suitable for the textured nature of the human retina. In this paper, we describe three major enhancements to the original formulation. The first is a visual tracking method using local illumination compensation to cope with the challenging visualization conditions. The second is an efficient pixel selection scheme for increased computational efficiency. The third is an entropy-based mosaic update method to dynamically improve the retina map during exploration. To evaluate the performance of the proposed method, we conducted several experiments on human subjects with a computer-assisted slit-lamp prototype. We also demonstrate the practical value of the system for photo documentation, diagnosis and intraoperative navigation.
激光光凝术目前是全球治疗威胁视力疾病的标准疗法，包括糖尿病性视网膜病变和视网膜静脉阻塞。裂隙灯生物显微镜是该手术最常用的设备，特别是用于治疗眼周边部。然而，通过生物显微镜只能观察到视网膜的一小部分，这使得定位和识别手术目标变得复杂，增加了治疗时间和患者的不适感。为了协助外科医生，我们提出了一种使用裂隙灯设备创建术中视网膜图以扩大视野的方法。基于 Richa 等人在 2012 年描述的拼贴方法，所提出的方法是直接方法和基于特征方法的组合，适用于人视网膜的纹理性质。在本文中，我们对原始公式进行了三个主要的改进。第一个是使用局部光照补偿的视觉跟踪方法，以应对具有挑战性的可视化条件。第二个是用于提高计算效率的高效像素选择方案。第三个是基于熵的拼贴更新方法，用于在探索过程中动态地改进视网膜图。为了评估所提出方法的性能，我们在具有计算机辅助裂隙灯原型的人体上进行了多次实验。我们还展示了该系统在照片记录、诊断和术中导航方面的实际价值。
