Risk in interstitial pneumonia (IP) is assessed routinely by the Gender–Age–Physiology (GAP) score from pulmonary function and the tricuspid regurgitation pressure gradient (TRPG) on echocardiography. This study evaluated whether the percent perfusion defect (
Temporal subtraction (TS) imaging highlights interval changes by computing a voxel-wise difference between spatially registered serial CT examinations, converting side-by-side comparison into a single map of change. Although TS head CT has been validated for acute cerebral infarction detection, its application across the broader spectrum of intracranial pathologies has not been systematically described. We present a pictorial review of twelve clinical cases covering hemorrhagic, ischemic, vascular, neoplastic, and degenerative pathologies. TS imaging was particularly effective for lesions near the visual detection threshold, multi-focal interval findings, and bilateral symmetric changes. It also supported exclusion of new lesions in structurally complex backgrounds. Characteristic artifacts from source-image degradation, scanner protocol differences, and retained contrast are also illustrated. TS head CT is a broadly applicable reading aid with potential to improve diagnostic conspicuity across a wide range of intracranial pathologies. Awareness of characteristic artifacts is essential for accurate interpretation.
Multiparametric PET separates tracer signal into bound and free fractions via reconstructions that reflect the net trapping rate (Ki) and apparent distribution volume (DV). This study aimed to investigate differences in background parenchymal uptake (BPU) between patients with and without breast cancer using multiparametric PET and to evaluate differences in primary tumor uptake according to hormone receptor status. This retrospective case-control study included female patients (n = 48) with newly diagnosed breast cancer and 146 patients without breast cancer. Patients with breast cancer under or after treatment and patients with bilateral breast cancer were excluded. Enrolled patients underwent whole-body dynamic PET and three quantitative indices representing BPU (maximum standardized uptake value [SUVmax], Ki and DV) were calculated. The primary tumor uptake was calculated between estrogen- or progesterone-receptor-positive and -negative groups. The mean SUVmax, Ki and DV of breast cancer cases were 1.39 ± 0.352, 4.88 × 10 − 3 ± 1.61 × 10 − 3 and 24.2 ± 15.4 respectively, whereas in control cases, mean SUVmax, Ki and DV were 1.10 ± 0.320, 3.96 × 10 − 3 ± 1.25 × 10 − 3 and 17.1 ± 10.8 respectively (P < 0.001, P < 0.001, and P = 0.004). The areas under the curve from the ROC analysis for breast cancer presence were calculated as 0.727, 0.681 and 0.653 respectively. In addition, age-stratified analysis showed that SUVmax and Ki were significantly higher in patients with breast cancer than in patients without breast cancer. Regarding the primary tumor uptake, Ki was significantly higher in the estrogen receptor-positive group. Multiparametric PET revealed that pure glucose metabolism is significantly elevated in the background mammary glands of patients with breast cancer, and the Ki in the primary tumor is associated with ER status. Dynamic PET imaging may be a useful imaging biomarker for the development of breast cancer.
This prospective study evaluated the 1 year safety and efficacy of stereotactic arrhythmia radioablation (STAR) delivered using the CyberKnife system for refractory ventricular tachycardia (VT) in Japanese patients, in accordance with a prespecified clinical protocol. Three male patients with radiofrequency catheter ablation (RFCA)-refractory VT and structural heart disease, namely hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and ischemic cardiomyopathy (ICM), were enrolled. A single fraction of 25 Gy was delivered to the target volume defined by multimodal image fusion. The primary endpoint was the absence of Grade ≥ 3 treatment-related adverse events within 12 months. The primary endpoint was achieved, with no acute or subacute Grade ≥ 3 toxicities observed in any patient during the first year. Although all patients experienced a reduction in VT burden, the clinical course differed by etiology. Cases 2 (DCM) and 3 (ICM) showed typical responses, including delayed efficacy and late recurrence requiring repeat RFCA. In contrast, Case 1 (HCM), with a substantially larger target volume (133 mL), showed a rapid response but a progressive decline in left ventricular ejection fraction by myocardial scintigraphy, from 59.7
Robotic systems for computed tomography (CT)-guided needle insertion have been developed to address the limitations of conventional manual needle insertion. Thus far, various robotic systems have been clinically implemented, and accumulating evidence has suggested their clinical utility. The evidence has evolved beyond initial feasibility and early clinical experience to include larger observational and comparative studies. These studies have demonstrated high success rates of robot-assisted needle insertion in various CT-guided interventions, including thermal ablation, biopsy, and preoperative localization. Furthermore, an increasing number of comparative studies have demonstrated the advantages of robot-assisted procedures over conventional manual procedures. These advantages include improved needle insertion accuracy and reduced radiation doses to patients and/or physicians. Although most currently available robotic systems are needle-guiding robots designed to align a needle guide with a predetermined insertion trajectory, we have developed a CT-guided needle insertion robot capable of robotic needle advancement via remote control. Clinical studies have demonstrated the feasibility of robotic needle insertion using this system, as well as needle placement accuracy comparable to that of manual procedures, while eliminating radiation exposure to physicians. The integration of artificial intelligence and the implementation of telerobotic interventions are expected to contribute significantly to the further advancement of robotic systems for CT-guided needle insertion. This narrative review summarizes the current clinical implementations and available evidence for robotic systems for CT-guided needle insertion, including our system, and discusses future perspectives in this field.
