Community Survey Results Show that Standardisation of Preclinical Imaging Techniques Remains a Challenge

Abstract Purpose To support acquisition of accurate, reproducible and high-quality preclinical imaging data, various standardisation resources have been developed over the years. However, it is unclear the impact of those efforts in current preclinical imaging practices. To better understand the status quo in the field of preclinical imaging standardisation, the STANDARD group of the European Society of Molecular Imaging (ESMI) put together a community survey and a forum for discussion at the European Molecular Imaging Meeting (EMIM) 2022. This paper reports on the results from the STANDARD survey and the forum discussions that took place at EMIM2022. Procedures The survey was delivered to the community by the ESMI office and was promoted through the Society channels, email lists and webpages. The survey contained seven sections organised as generic questions and imaging modality-specific questions. The generic questions focused on issues regarding data acquisition, data processing, data storage, publishing and community awareness of international guidelines for animal research. Specific questions on practices in optical imaging, PET, CT, SPECT, MRI and ultrasound were further included. Results Data from the STANDARD survey showed that 47% of survey participants do not have or do not know if they have QC/QA guidelines at their institutes. Additionally, a large variability exists in the ways data are acquired, processed and reported regarding general aspects as well as modality-specific aspects. Moreover, there is limited awareness of the existence of international guidelines on preclinical (imaging) research practices. Conclusions Standardisation of preclinical imaging techniques remains a challenge and hinders the transformative potential of preclinical imaging to augment biomedical research pipelines by serving as an easy vehicle for translation of research findings to the clinic. Data collected in this project show that there is a need to promote and disseminate already available tools to standardise preclinical imaging practices. </jats:sec

Diagnostic accuracy of post-mortem MRI for thoracic abnormalities in fetuses and children

OBJECTIVES: To compare the diagnostic accuracy of post-mortem magnetic resonance imaging (PMMR) specifically for non-cardiac thoracic pathology in fetuses and children, compared with conventional autopsy. METHODS: Institutional ethics approval and parental consent was obtained. A total of 400 unselected fetuses and children underwent PMMR before conventional autopsy, reported blinded to the other dataset. RESULTS: Of 400 non-cardiac thoracic abnormalities, 113 (28 %) were found at autopsy. Overall sensitivity and specificity (95 % confidence interval) of PMMR for any thoracic pathology was poor at 39.6 % (31.0, 48.9) and 85.5 % (80.7, 89.2) respectively, with positive predictive value (PPV) 53.7 % (42.9, 64.0) and negative predictive value (NPV) 77.0 % (71.8, 81.4). Overall agreement was 71.8 % (67.1, 76.2). PMMR was most sensitive at detecting anatomical abnormalities, including pleural effusions and lung or thoracic hypoplasia, but particularly poor at detecting infection. CONCLUSIONS: PMMR currently has relatively poor diagnostic detection rates for the commonest intra-thoracic pathologies identified at autopsy in fetuses and children, including respiratory tract infection and diffuse alveolar haemorrhage. The reasonable NPV suggests that normal thoracic appearances at PMMR exclude the majority of important thoracic lesions at autopsy, and so could be useful in the context of minimally invasive autopsy for detecting non-cardiac thoracic abnormalities. KEY POINTS: • PMMR has relatively poor diagnostic detection rates for common intrathoracic pathology • The moderate NPV suggests that normal PMMR appearances exclude most important abnormalities • Lung sampling at autopsy remains the "gold standard" for pulmonary pathology

Skunk River Review September 1989, vol 1 no 1

https://openspace.dmacc.edu/skunkriver/1004/thumbnail.jp

Community Survey Results Show that Standardisation of Preclinical Imaging Techniques Remains a Challenge

PurposeTo support acquisition of accurate, reproducible and high-quality preclinical imaging data, various standardisation resources have been developed over the years. However, it is unclear the impact of those efforts in current preclinical imaging practices. To better understand the status quo in the field of preclinical imaging standardisation, the STANDARD group of the European Society of Molecular Imaging (ESMI) put together a community survey and a forum for discussion at the European Molecular Imaging Meeting (EMIM) 2022. This paper reports on the results from the STANDARD survey and the forum discussions that took place at EMIM2022. ProceduresThe survey was delivered to the community by the ESMI office and was promoted through the Society channels, email lists and webpages. The survey contained seven sections organised as generic questions and imaging modality-specific questions. The generic questions focused on issues regarding data acquisition, data processing, data storage, publishing and community awareness of international guidelines for animal research. Specific questions on practices in optical imaging, PET, CT, SPECT, MRI and ultrasound were further included. ResultsData from the STANDARD survey showed that 47% of survey participants do not have or do not know if they have QC/QA guidelines at their institutes. Additionally, a large variability exists in the ways data are acquired, processed and reported regarding general aspects as well as modality-specific aspects. Moreover, there is limited awareness of the existence of international guidelines on preclinical (imaging) research practices. ConclusionsStandardisation of preclinical imaging techniques remains a challenge and hinders the transformative potential of preclinical imaging to augment biomedical research pipelines by serving as an easy vehicle for translation of research findings to the clinic. Data collected in this project show that there is a need to promote and disseminate already available tools to standardise preclinical imaging practices

Simulated required accuracy of image registration tools for targeting high-grade cancer components with prostate biopsies

Contains fulltext : 117653.pdf (publisher's version ) (Closed access)OBJECTIVES: To estimate the required spatial alignment accuracy for correctly grading 95 \% of peripheral zone (PZ) prostate cancers using a system for multiparametric magnetic resonance (MR)-guided ultrasound (US) biopsies. METHODS: PZ prostate tumours were retrospectively annotated on multiparametric MR series using prostatectomy specimens as reference standard. Tumours were grouped based on homogeneous and heterogeneous apparent diffusion coefficient (ADC) values using an automated ADC texture analysis method. The proportion of heterogeneous tumours containing a distinct, high Gleason grade tumour focus yielding low ADC values was determined. Both overall tumour and high-grade focal volumes were calculated. All high-grade target volumes were then used in a simulated US biopsy system with adjustable accuracy to determine the hit rate. RESULTS: An ADC-determined high-grade tumour focus was found in 63 \% of the PZ prostate tumours. The focal volumes were significantly smaller than the total tumour volumes (median volume of 0.3 ml and 1.1 ml respectively). To correctly grade 95 \% of the aggressive tumour components the target registration error (TRE) should be smaller than 1.9 mm. CONCLUSIONS: To enable finding the high Gleason grade component in 95 \% of PZ prostate tumours with MR-guided US biopsies, a technical registration accuracy of 1.9 mm is required. KEY POINTS : • MRI can identify foci of prostatic cancer with reduced apparent diffusion coefficients • Sixty-three per cent of prostatic peripheral zone tumours contain high-grade tumour low ADC foci • The median volume of such foci is 0.3 ml • Biopsy targets are significantly smaller than whole tumour volumes • Simulated registration accuracy is 1.9 mm for correctly grading 95 \% of tumours

Whole body PD-L1 PET in patients with NSCLC and melanoma.

Background: PD-(L)1 immunotherapy is effective in multiple tumors, including NSCLC and melanoma, but tumor PD-L1 IHC correlates only moderately with treatment outcome. This study aims to assess 1) safety of 18F-BMS-986192 (18F-PD-L1) in human, 2) PD-L1 quantification in tumors using 18F-PD-L1 PET, 3) PD-L1 PET correlation with IHC and treatment outcome, and 4) intra and inter subject tracer uptake variability. Methods: Pts with NSCLC (N = 10) and melanoma (N = 3) were included. At baseline, pts received a static or multiphase dynamic whole body PET scan after injecting 200 MBq 18F-BMS-986192. For NSCLC pts, (1) SUV(max, peak and mean) were measured for each delineable tumor (N = 32, 1-7 tumors/pt), (2) PD-L1 IHC (28.8 assay) was performed on the biopsy, and (3) response to Nivolumab therapy assessed by RECIST 1.1. Intra and inter subject variability and intraclass correlation were calculated using SUVs of all assessed tumors. Equal variance for PD-L1 status was evaluated by a Levene’s test. Four (3 female) pts underwent dosimetry study (ICRP 60). Results: No AEs related to radiotracer was observed. Dosimetry study demonstrated whole body exposure of 30 mGy at dose > 1400 MBq. Biodistribution among pts is comparable. PD-L1 IHC from 13 biopsied lesions were evaluated, 5 <1%, 4 ≥1%, and 4 ≥50%. Tumor tracer uptake was measured in NSCLC pts and categorized by PDL-1 IHC as ≥50% or <50%. Clinical trial information: 2015-004760-11. Tumor SUVs did not correlate with RECIST 1.1 assessment. Lesion heterogeneity was reflected in both inter and intra pt variability (CVinter = 41%, CVintra = 53%, ICC = 0.41 for SUVpeak). Levene’s test showed no significance in variability between the two PD-L1 categories. Conclusions: PET-imaging with 18F-BMS-986192 is safe and feasible in pts with NSCLC and melanoma. Pts with higher PD-L1 PET SUV have higher PD-L1 by IHC. Intra pt variability is similar to inter pt variability. With limited number of pts, no clear correlation of PET PD-L1 and tumor response is observed. A prospective study with this tracer is underway to further investigate 18F-BMS-986192 in understanding of PD-L1 expression