Despite the advances made since the introduction of ultrasonography, computed tomography and magnetic resonance imaging, a wide discrepancy may occur between preoperative and peroperative staging of gastrointestinal malignancy with liver and peritoneal metastases. Diagnostic laparoscopy performed immediately before a planned laparotomy can provide valuable information for the accurate assessment and appropriate management of some forms of gastrointestinal malignancy, especially that of the liver and pancreas. For evaluation of small liver and retroperitoneal malignancies, intraoperative ultrasonography performed by laparotomy is of proven value. It is now technically possible to perform ultrasonography through a laparoscopic cannula using high-resolution ultrasonographic transducers. This combination of laparoscopy and ultrasonography was studied in 25 patients with established liver lesions, carcinoma of the gallbladder or pancreatic cancer. Additional information leading to a change in surgical approach was obtained in 20 patients. Laparoscopic ultrasonography, although still in a preliminary phase of development, is a simple and reliable technique that will contribute to more accurate staging of intra-abdominal malignancy.

The development of gene therapies for central nervous system disorders is challenging because it is difficult to translate preclinical data from current in vitro and in vivo models to the clinic. Therefore, we developed induced pluripotent stem cell (iPSC)-derived cerebral organoids as a model for recombinant adeno-associated virus (rAAV) capsid selection and for testing efficacy of AAV-based gene therapy in a human context. Cerebral organoids are physiological 3D structures that better recapitulate the human brain compared with 2D cell lines. To validate the model, we compared the transduction efficiency and distribution of two commonly used AAV serotypes (rAAV5 and rAAV9). In cerebral organoids, transduction with rAAV5 led to higher levels of vector DNA, transgenic mRNA, and protein expression as compared with rAAV9. The superior transduction of rAAV5 was replicated in iPSC-derived neuronal cells. Furthermore, rAAV5-mediated delivery of a human sequence-specific engineered microRNA to cerebral organoids led to a lower expression of its target ataxin-3. Our studies provide a new tool for selecting and deselecting AAV serotypes, and for demonstrating therapeutic efficacy of transgenes in a human context. Implementing cerebral organoids during gene therapy development could reduce the usage of animal models and improve translation to the clinic.

Pathogenesis of viral infections of the central nervous system (CNS) is poorly understood, and this is partly due to the limitations of currently used preclinical models. Brain organoid models can overcome some of these limitations, as they are generated from human derived stem cells, differentiated in three dimensions (3D), and can mimic human neurodevelopmental characteristics. Therefore, brain organoids have been increasingly used as brain models in research on various viruses, such as Zika virus, severe acute respiratory syndrome coronavirus 2, human cytomegalovirus, and herpes simplex virus. Brain organoids allow for the study of viral tropism, the effect of infection on organoid function, size, and cytoarchitecture, as well as innate immune response; therefore, they provide valuable insight into the pathogenesis of neurotropic viral infections and testing of antivirals in a physiological model. In this review, we summarize the results of studies on viral CNS infection in brain organoids, and we demonstrate the broad application and benefits of using a human 3D model in virology research. At the same time, we describe the limitations of the studies in brain organoids, such as the heterogeneity in organoid generation protocols and age at infection, which result in differences in results between studies, as well as the lack of microglia and a blood brain barrier.