This paper presents a novel PET geometry for breast cancer imaging. The scanner consists of a ‘stadium’ (a rectangle with two semi-circles on opposite sides) shaped ring, along with anterior and posterior panels to provide high sensitivity and high spatial resolution for an imaging field-of-view (FOV) that include both breasts, mediastinum and axilla. We simulated this total-breast PET system using GATE and reconstructed the coincidence events using a GPU-based list-mode image reconstruction implementing maximum likelihood expectation-maximization (ML-EM) algorithm. The rear-panel is made up of a single layer of LSO crystals (3.2נ3.2נ20 mm³ each), while the ‘stadium’-shaped elongated ring and the anterior panel are made with dual-layered LSO crystals (1.6נ1.6נ6 mm³ each). The energy resolution and coincidence resolving time of all detectors are assumed to be 12% and 250 ps full-width-at-half-maximum, respectively. Various sized simulated lesions (4, 5, 6 mm) having 4:1, 5:1, and 6:1 lesion-to-background radioactivity concentration ratios, mimicking different biological uptakes, were strategically located throughout a volumetric torso phantom. We compared system sensitivity and lesion detectability of the dedicated total-breast PET system to a state-of-the-art clinical whole-body PET scanner. The mean sensitivity of the total-breast PET system is 3.21 times greater than that of a whole-body PET scanner in the breast regions. The total-breast PET system also provides better contrast-recovery coefficients for lesions of all sizes and lesion-to-background ratios in the breast when compared to a reference clinical whole-body PET scanner. Receiver operating characteristics (ROC) study shows the area under the ROC curve is 0.948 and 0.924 for the total-breast system and the whole-body PET scanner, respectively, in the detection of 4 mm diameter lesions with 4:1 lesion-to-background ratio. This study demonstrates our novel geometry can provide an imaging FOV larger than conventional PEM systems to simultaneously image both breasts, chest wall and axillae with significantly improved lesion detectability in the breasts when compared to a whole-body PET scanner.

本文提出了一种用于乳腺癌成像的新型 PET 几何结构。扫描仪由一个“体育场”（一个在相对两侧有两个半圆的矩形）形环以及前面板和后面板组成，为成像视场 (FOV) 提供高灵敏度和高空间分辨率，其中包括双乳房、纵隔和腋窝。我们使用 GATE 模拟了这个全乳房 PET 系统，并使用基于 GPU 的列表模式图像重建实现了最大似然期望最大化 (ML-EM) 算法来重建巧合事件。后面板由单层 LSO 晶体（每层 3.2נ3.2נ20 mm ³）组成，而“体育场”形拉长环和前面板由双层 LSO 晶体（1.6נ1.6נ6毫米³每个）。假设所有探测器的能量分辨率和重合分辨率分别为 12% 和 250 ps 半峰全宽。具有 4:1、5:1 和 6:1 损伤与背景放射性浓度比的各种大小的模拟损伤（4、5、6 毫米），模拟不同的生物摄取，战略性地位于整个体积躯干幻影。我们将专用全乳房 PET 系统的系统灵敏度和病变可检测性与最先进的临床全身 PET 扫描仪进行了比较。全乳房PET系统的平均灵敏度是乳房区域全身PET扫描仪的3.21倍。与参考临床全身 PET 扫描仪相比，全乳房 PET 系统还为乳房中各种大小的病变和病变与背景的比率提供了更好的对比恢复系数。接受者操作特征 (ROC) 研究显示，全乳系统和全身 PET 扫描仪在检测直径为 4 毫米、病灶比为 4:1 的病灶时，ROC 曲线下面积分别为 0.948 和 0.924。背景比。这项研究表明，与全身 PET 扫描仪相比，我们的新型几何结构可以提供比传统 PEM 系统更大的成像 FOV，以同时对乳房、胸壁和腋窝进行成像，并显着提高了乳房病变的可检测性。全乳系统和全身 PET 扫描仪在检测直径为 4 毫米的病灶时分别为 948 和 0.924，病灶与背景比为 4:1。这项研究表明，与全身 PET 扫描仪相比，我们的新型几何结构可以提供比传统 PEM 系统更大的成像 FOV，以同时对乳房、胸壁和腋窝进行成像，并显着提高了乳房病变的可检测性。全乳系统和全身 PET 扫描仪在检测直径为 4 毫米的病灶时分别为 948 和 0.924，病灶与背景比为 4:1。这项研究表明，与全身 PET 扫描仪相比，我们的新型几何结构可以提供比传统 PEM 系统更大的成像 FOV，以同时对乳房、胸壁和腋窝进行成像，并显着提高了乳房病变的可检测性。