A practical protocol for shortening reconstruction time of volumetric data and imaging bilateral middle cerebral arteries for thrombectomy in acute ischemic stroke using an 80-row computed tomography scanner.

Time-consuming reconstruction of volumetric data by area-detector-computed tomography (ADCT) scanning and narrow coverage of small-row ADCT may hinder volumetric scanning in acute stroke stage. To design a practical protocol of volumetric scanning for thrombectomy using an 80-row ADCT. An imaging protocol that focuses on the middle cerebral arteries by tilting the gantry of an 80-row ADCT with 0.5-mm-thick detectors can shorten the reconstruction time by 1.0-mm thickness scanning without subtraction. The reconstruction time of small volumetric data was 69 second. This practical protocol is applicable before thrombectomy in different stroke centres with narrow-coverage ADCT scanners.

CT angiography of neonates and infants: comparison of radiation dose and image quality of target mode prospectively ECG-gated 320-MDCT and ungated helical 64-MDCT.

OBJECTIVE. The purpose of this study was to evaluate the radiation dose and image quality of target mode prospectively ECG-gated volumetric CT angiography (CTA) performed with a 320-MDCT scanner compared with the radiation dose and image quality of ungated helical CTA performed with a 64-MDCT scanner. MATERIALS AND METHODS. An experience with CTA for cardiovascular indications in neonates and infants 0-6 months old was retrospectively assessed. Radiation doses and quantitative and qualitative image quality scores of 28 CTA examinations performed with a 320-MDCT scanner and volumetric target mode prospective ECG gating plus iterative reconstruction (target mode) were compared with the doses and scores of 28 CTA examinations performed with a 64-MDCT scanner and ungated helical scanning plus filtered back projection reconstruction (ungated mode). All target mode studies were performed during free breathing. Seven ungated CTA examinations (25%) were performed with general endotracheal anesthesia. The findings of 17 preoperative CTA examinations performed in target mode were also compared with surgical reports for evaluation of diagnostic accuracy. RESULTS. All studies performed with target mode technique were diagnostic for the main clinical indication. Effective doses were significantly lower in the target mode group (0.51 ± 0.19 mSv) compared with the ungated mode group (4.8 ± 1.4 mSv) (p < 0.0001). Quantitative analysis revealed no statistically significant difference between the two groups with respect to signal-to-noise ratio (of pulmonary artery and aorta) and contrast-to-noise ratio. Subjective image quality was significantly better with target mode than with ungated mode (p < 0.0001). CONCLUSION. Target mode prospectively ECG-gated volumetric scanning with iterative reconstruction performed with a 320-MDCT scanner has several benefits in cardiovascular imaging of neonates and infants, including low radiation dose, improved image quality, high diagnostic accuracy, and ability to perform free-breathing studies.

Cost-effective 3D scanning and printing technologies for outer ear reconstruction: current status.

Current 3D scanning and printing technologies offer not only state-of-the-art developments in the field of medical imaging and bio-engineering, but also cost and time effective solutions for surgical reconstruction procedures. Besides tissue engineering, where living cells are used, bio-compatible polymers or synthetic resin can be applied. The combination of 3D handheld scanning devices or volumetric imaging, (open-source) image processing packages, and 3D printers form a complete workflow chain that is capable of effective rapid prototyping of outer ear replicas. This paper reviews current possibilities and latest use cases for 3D-scanning, data processing and printing of outer ear replicas with a focus on low-cost solutions for rehabilitation engineering.

Pencil Beam Scanning Proton Therapy for Paediatric Neuroblastoma with Motion Mitigation Strategy for Moving Target Volumes.

AIMS: More efforts are required to minimise late radiation side-effects for paediatric patients. Pencil beam scanning proton beam therapy (PBS-PT) allows increased sparing of normal tissues while maintaining conformality, but is prone to dose degradation from interplay effects due to respiratory motion. We report our clinical experience of motion mitigation with volumetric rescanning (vRSC) and outcomes of children with neuroblastoma. MATERIALS AND METHODS: Nineteen patients with high-risk (n = 16) and intermediate-risk (n = 3) neuroblastoma received PBS-PT. The median age at PBS-PT was 3.5 years (range 1.2-8.6) and the median PBS-PT dose was 21 Gy (relative biological effectiveness). Most children (89%) were treated under general anaesthesia. Seven patients (37%) underwent four-dimensional computed tomography for motion assessment and were treated with vRSC for motion mitigation. RESULTS: The mean result of maximum organ motion was 2.7 mm (cranial-caudal), 1.2 mm (left-right), 1.0 mm (anterior-posterior). Four anaesthetised children (21%) showing <5 mm motion had four-dimensional dose calculations (4DDC) to guide the number of vRSC. The mean deterioration or improvement to the planning target volume covered by 95% of the prescribed dose compared with static three-dimensional plans were: 4DDC no vRSC, -0.6%; 2 vRSC, +0.3%; 4 vRSC, +0.3%; and 8 vRSC, +0.1%. With a median follow-up of 14.9 months (range 2.7-49.0) there were no local recurrences. The 2-year overall survival was 94% and distant progression-free survival was 76%. Acute grade 2-4 toxicity was 11%. During the limited follow-up time, no late toxicities were observed. CONCLUSIONS: The early outcomes of mainly high-risk patients with neuroblastoma treated with PBS-PT were excellent. With a subset of our cohort undergoing PBS-PT with vRSC we have shown that it is logistically feasible and safe. The clinical relevance of vRSC is debatable in anaesthetised children with small pre-PBS-PT motion of <5 mm.

Whole Breast Ultrasound: Comparison of the Visibility of Suspicious Lesions with Automated Breast Volumetric Scanning Versus Hand-Held Breast Ultrasound.

RATIONALE AND OBJECTIVES: To assess how well radiologists visualize relevant features of lesions seen with automated breast volumetric scanning (ABVS) in comparison to hand-held breast ultrasound in women going to breast biopsy. MATERIALS AND METHODS: Twenty-five subjects were recruited from women who were scheduled to undergo a breast biopsy for at least one Breast Imaging-Reporting and Data System four or five lesion identified in a diagnostic setting. In this institutional review board-approved study, the subjects underwent imaging of the breast(s) of concern using a dedicated system that allowed both hand-held breast ultrasound and ABVS. Five experienced breast radiologists reviewed the 30 lesions in 25 subjects in a reader study. Each reader was asked to specify the lesion type, size, imaging features, Breast Imaging-Reporting and Data System, and suspicion of malignancy and to compare the lesion characteristics of shape and margins between the two modalities. RESULTS: Seven (23.3%) masses were malignant and 23 (76.4%) were benign. Across all lesions regardless of size or final pathology, there was no significant difference in sensitivity or specificity (P > .15) between the two modalities. For malignant lesions, the reader visualization confidence scores between the two ultrasound modalities were not significantly different (P > .1). However, analysis for nonmalignant cases showed a statistically significant increase in reader visualization confidence in lesion shape and margins (P < .001). CONCLUSIONS: Radiologists showed increased confidence in visualization of benign masses and equal confidence in suspicious masses with ABVS imaging. This information could help decrease the need for additional hand-held imaging after automated whole breast ultrasound.