Radioguided surgery (RGS) is a medical practice which thanks to a radiopharmaceutical tracer and a probe allows the surgeon to identify tumor residuals up to a millimetric resolution in real-time. The employment of ${\beta }^{-}$ emitters, instead of $\gamma$ or ${\beta }^{+}$, reduces background from healthy tissues, administered activity to the patient, and medical exposure. In a previous work the possibility of using a CMOS Imager (Aptina MT9V011), initially designed for visible light imaging, to detect ${\beta }^{-}$ from ⁹⁰Y or ⁹⁰Sr sources has been established. Because of its possible application as counting probe in RGS, the performances of MT9V011 in clinical-like conditions were studied.¹

Through horizontal scans on a collimated ⁹⁰Sr source of different sizes (1, 3, 5, 7 mm), we have determined relationships between scan fit parameters and the source dimension, namely A quadratic correlation and a linear dependency of, respectively, signal integrated over scan interval, and maximum signal against source diameter, are determined. Horizontal scan measurements on a source, interposing collimators of different size, aim to determine relationships or correlations between scan fit parameters and source dimension. A quadratic correlation and a linear dependency of, respectively, signal integrated over scan interval, and maximum signal against source diameter are determined.

In order to get closer to clinical conditions, agar–agar phantoms containing ${}^{90}Y$ with different dimensions and activities were prepared. A ${}^{90}Y$ phantom is characterized by a central spot and a ring all around, for simulating both signal (tumor) and background (surrounding healthy tissue). The relationship found between scan maximum and ${}^{90}Sr$ source diameter is then exploited to extract the concentration ratio between spot and external ring of the ${}^{90}Y$ phantom. This observable, defined as the ratio between the tumor and the nearby healthy tissues uptake simulates the Tumor-to-Non-tumor Ratio (TNR). With the aim of evaluating the sensor’s ability to discriminate signal from background relying on the significance parameter, a further ${}^{90}Y$ phantom, featuring a well-known and clinical-like activity will mimic the signal only condition. This result is used to extrapolate to different source sizes, after having estimated the background for various TNR. The obtained significance values suggest that the MT9V011 sensor is capable of distinguishing a signal from an estimated background, depending on the interplay among TNR, acquisition time and tumor diameter.

放射引导手术 (RGS) 是一种医疗实践，这要归功于放射性药物示踪剂和探针，外科医生可以实时识别高达毫米分辨率的肿瘤残留物。的就业${\beta }^{-}$ 发射器，而不是 $\gamma$ 或者 ${\beta }^{+}$, 减少来自健康组织的背景、对患者进行的活动以及医疗暴露。在以前的工作中，使用最初设计用于可见光成像的 CMOS 成像器 (Aptina MT9V011) 来检测的可能性${\beta }^{-}$已经建立了来自⁹⁰ Y 或⁹⁰ Sr 的来源。由于其可能用作 RGS 中的计数探针，因此研究了 MT9V011 在类似临床条件下的性能。¹

通过对不同尺寸（1、3、5、7 毫米）的准直⁹⁰ Sr 源进行水平扫描，我们确定了扫描拟合参数与源尺寸之间的关系，即二次相关和信号积分的线性相关性。确定扫描间隔内的最大信号和源直径的最大信号。源上的水平扫描测量，插入不同尺寸的准直器，旨在确定扫描拟合参数和源尺寸之间的关系或相关性。分别确定在扫描间隔内积分的信号和最大信号对源直径的二次相关和线性相关性。

为了更接近临床情况，琼脂模型含有 ${}^{90}是$准备了不同的维度和活动。一种${}^{90}是$体模的特点是一个中心点和一个环，用于模拟信号（肿瘤）和背景（周围健康组织）。扫描最大值和${}^{90}秒r$ 然后利用源直径来提取点和外环之间的浓度比 ${}^{90}是$幻影。此可观察值定义为肿瘤与附近健康组织摄取之间的比率，模拟了肿瘤与非肿瘤的比率 (TNR)。为了评估传感器根据显着性参数从背景中区分信号的能力，进一步${}^{90}是$phantom 具有众所周知的类似临床的活动，将模拟仅信号条件。在估计了各种 TNR 的背景后，该结果用于外推到不同的源大小。获得的显着性值表明 MT9V011 传感器能够从估计的背景中区分信号，这取决于 TNR、采集时间和肿瘤直径之间的相互作用。