Diagnosis of neonatal neuroblastoma with postmortem magnetic resonance imaging

Usefulness of virtual autopsy in diagnosing pathologies in the paediatric population: A systematic review

Objective

Virtual autopsy is a non-invasive/minimally invasive method for conducting an autopsy, with the assistance of imaging techniques. We aim to review the benefits of virtual autopsy in detecting pathologies in the paediatric population.

Method

The procedure adhered to Institute of Medicine and Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Seven databases including MEDLINE and SCOPUS were searched for articles published 2010-2020 worldwide in English. A narrative synthesis of the findings of included studies was carried out to discuss and summarize the results of the review.

Results

From 686 studies on paediatric deaths, 23 met selection/quality criteria. Virtual autopsy was better than conventional autopsy in detecting skeletal lesions and bullet trajectory, thus a crucial tool in the investigation of traumatic and firearm deaths. Virtual autopsy was superior to conventional autopsy in identifying the point of bleeding in postoperative deaths and objectively quantifying air/fluid in body cavities. Virtual autopsy was a useful adjunct for detecting pulmonary thrombo-embolism, foreign body aspiration, drowning and metastatic malignancies. The use of non-contrast imaging in investigating natural paediatric deaths did not offer more information than conventional autopsy. Misinterpretation of normal post-mortem changes as pathological findings was another disadvantage of virtual autopsy leading to erroneous conclusions. But accuracy may be improved with contrast enhancement and post-mortem magnetic resonance imaging.

Conclusion

Virtual autopsy is a crucial tool in the investigation of traumatic and firearm deaths in the paediatric population. Virtual autopsy will be useful as an adjunct to conventional autopsy in asphyxial deaths, stillbirths and decomposed bodies. Virtual autopsy has limited value in differentiating antemortem and post-mortem changes with the added risk of misinterpretations, therefore should be used with caution in natural deaths.

Neuroblastoma-targeting triangular gadolinium oxide nanoplates for precise excision of cancer

Neuroblastoma accounts for 8-10% of malignancies in infants and children. It is urgent to develop an appropriate theranostic agent for effective diagnosis and therapy of neuroblastoma. Herein, we constructed RVG peptide and IRDye800-conjugated bovine serum albumin-coated triangular gadolinium oxide nanoplates (RVG&IRDye800-Gd₂O₃ TNs) as a targeting MRI agent for the diagnosis of neuroblastoma preoperation and a fluorescence imaging agent for the guidance of the precise excision of the neuroblastoma in surgery. RVG&IRDye800-Gd₂O₃ TNs have uniform edge length. The RVG&IRDye800-Gd₂O₃ TNs show remarkably enhanced affinity to both mouse- and human-derived neuroblastoma cells compared with IRDye800-Gd₂O₃ TNs (3.07-fold and 3.02-fold, respectively). Because of the increased accumulation in tumor cells, RVG&IRDye800-Gd₂O₃ TNs exhibit signals threefold to fivefold higher than the surrounding normal tissues, which is propitious to the diagnosis of neuroblastoma preoperation and provides real-time visual guidance of the precise excision of the neuroblastoma. Most importantly, with the guidance of the fluorescence imaging agent, the survival rate increased from 0% to 80% 42 days after surgery compared with that in conventional surgery. These findings indicated that the RVG peptide combined with IRDye800-Gd₂O₃ TNs has the potential to improve the diagnosis and treatment of patients with neuroblastoma. STATEMENT OF SIGNIFICANCE: In this study, we prepared RVG peptide and IRDye800-conjugated bovine serum albumin-coated triangular gadolinium oxide nanoplates (RVG&IRDye800-Gd₂O₃ TNs) as a targeting MRI agent for the diagnosis of neuroblastoma preoperation and a fluorescence imaging agent for the guidance of the precise excision of the neuroblastoma during surgery. Neuroblastoma was accurately located by MRI imaging, and the tumor margin could be real-time monitored through near-infrared fluorescence imaging. The RVG&IRDye800-Gd₂O₃ TNs exhibit signals threefold to fivefold higher than those in the surrounding normal tissues, which is propitious to the diagnosis of the neuroblastoma preoperation and provides real-time visual guidance of the precise excision of the neuroblastoma. With the guidance of the fluorescence imaging agent in surgery, the survival rate increased from 0% to 80% 42 days after surgery compared with that in conventional surgery.