1
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Fredericks K, Kriel J, Engelbrecht L, Mercea PA, Widhalm G, Harrington B, Vlok I, Loos B. 5-ALA localises to the autophagy compartment and increases its fluorescence upon autophagy enhancement through caloric restriction and spermidine treatment in human glioblastoma. Biochem Biophys Rep 2024; 37:101642. [PMID: 38288282 PMCID: PMC10823107 DOI: 10.1016/j.bbrep.2024.101642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 12/29/2023] [Accepted: 01/08/2024] [Indexed: 01/31/2024] Open
Abstract
Glioblastoma Multiforme (GBM) is the most invasive and prevalent Central Nervous System (CNS) malignancy. It is characterised by diffuse infiltrative growth and metabolic dysregulation that impairs the extent of surgical resection (EoR), contributing to its poor prognosis. 5-Aminolevulinic acid (5-ALA) fluorescence-guided surgical resection (FGR) takes advantage of the preferential generation of 5-ALA-derived fluorescence signal in glioma cells, thereby improving visualisation and enhancing the EoR. However, despite 5-ALA FGR is a widely used technique in the surgical management of malignant gliomas, the infiltrative tumour margins usually show only vague or no visible fluorescence and thus a significant amount of residual tumour tissue may hence remain in the resection cavity, subsequently driving tumour recurrence. To investigate the molecular mechanisms that govern the preferential accumulation of 5-ALA in glioma cells, we investigated the precise subcellular localisation of 5-ALA signal using Correlative Light and Electron Microscopy (CLEM) and colocalisation analyses in U118MG glioma cells. Our results revealed strong 5-ALA signal localisation in the autophagy compartment - specifically autolysosomes and lysosomes. Flow cytometry was employed to investigate whether autophagy enhancement through spermidine treatment (SPD) or nutrient deprivation/caloric restriction (CR) would enhance 5-ALA fluorescence signal generation. Indeed, SPD, CR and a combination of SPD/CR treatment significantly increased 5-ALA signal intensity, with a most robust increase in signal intensity observed in the combination treatment of SPD/CR. When using 3-D glioma spheroids to assess the effect of 5-ALA on cellular ultrastructure, we demonstrate that 5-ALA exposure leads to cytoplasmic disruption, vacuolarisation and large-scale mitophagy induction. These findings not only suggest a critical role for the autophagy compartment in 5-ALA engagement and signal generation but also point towards a novel and practically feasible approach to enhance 5-ALA fluorescence signal intensity. The findings may highlight that indeed autophagy control may serve as a promising avenue to promote an improved resection and GBM prognosis.
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Affiliation(s)
- Kim Fredericks
- Department of Physiological Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Jurgen Kriel
- Central Analytical Facility, Microscopy Unit, Stellenbosch University, South Africa
| | - Lize Engelbrecht
- Central Analytical Facility, Microscopy Unit, Stellenbosch University, South Africa
| | | | - Georg Widhalm
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Brad Harrington
- Department of Neurosurgery, Stellenbosch University, Cape Town, South Africa
| | - Ian Vlok
- Department of Neurosurgery, Stellenbosch University, Cape Town, South Africa
| | - Ben Loos
- Department of Physiological Sciences, Stellenbosch University, Stellenbosch, South Africa
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2
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Yang J, Qu J, Teng X, Zhu W, Xu Y, Yang Y, Qian X. Tumor Microenvironment-Responsive Hydrogel for Direct Extracellular ATP Imaging-Guided Surgical Resection with Clear Boundaries. Adv Healthc Mater 2023; 12:e2301084. [PMID: 37219912 DOI: 10.1002/adhm.202301084] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/20/2023] [Indexed: 05/24/2023]
Abstract
Most solid tumors are clinically treated using surgical resection, and the presence of residual tumor tissues at the surgical margins often determines tumor survival and recurrence. Herein, a hydrogel (Apt-HEX/Cp-BHQ1 Gel, termed AHB Gel) is developed for fluorescence-guided surgical resection. AHB Gel is constructed by tethering a polyacrylamide hydrogel and ATP-responsive aptamers together. It exhibits strong fluorescence under high ATP concentrations corresponding to the TME (100-500 µm) but shows little fluorescence at low ATP concentrations (10-100 nm) such as those in normal tissues. AHB Gel can rapidly (within 3 min) emit fluorescence after exposure to ATP, and the fluorescence signal only occurs at sites exposed to high ATP, resulting in a clear boundary between the ATP-high and ATP-low regions. In vivo, AHB Gel exhibits specific tumor-targeting capacity with no fluorescence response in normal tissue, providing clear tumor boundaries. In addition, AHB Gel has good storage stability, which is conducive to its future clinical application. In summary, AHB Gel is a novel tumor microenvironment-targeted DNA-hybrid hydrogel for ATP-based fluorescence imaging. It can enable the precise imaging of tumor tissues, showing promising application in fluorescence-guided surgeries in the future.
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Affiliation(s)
- Jingyi Yang
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, P. R. China
| | - Jiahao Qu
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, P. R. China
| | - Xuanming Teng
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, P. R. China
| | - Weiping Zhu
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, P. R. China
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai, 200237, P. R. China
| | - Yufang Xu
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, P. R. China
| | - Yangyang Yang
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, P. R. China
| | - Xuhong Qian
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, P. R. China
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China
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3
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Van Hese L, De Vleeschouwer S, Theys T, Rex S, Heeren RMA, Cuypers E. The diagnostic accuracy of intraoperative differentiation and delineation techniques in brain tumours. Discov Oncol 2022; 13:123. [PMID: 36355227 PMCID: PMC9649524 DOI: 10.1007/s12672-022-00585-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 10/22/2022] [Indexed: 11/11/2022] Open
Abstract
Brain tumour identification and delineation in a timeframe of seconds would significantly guide and support surgical decisions. Here, treatment is often complicated by the infiltration of gliomas in the surrounding brain parenchyma. Accurate delineation of the invasive margins is essential to increase the extent of resection and to avoid postoperative neurological deficits. Currently, histopathological annotation of brain biopsies and genetic phenotyping still define the first line treatment, where results become only available after surgery. Furthermore, adjuvant techniques to improve intraoperative visualisation of the tumour tissue have been developed and validated. In this review, we focused on the sensitivity and specificity of conventional techniques to characterise the tumour type and margin, specifically fluorescent-guided surgery, neuronavigation and intraoperative imaging as well as on more experimental techniques such as mass spectrometry-based diagnostics, Raman spectrometry and hyperspectral imaging. Based on our findings, all investigated methods had their advantages and limitations, guiding researchers towards the combined use of intraoperative imaging techniques. This can lead to an improved outcome in terms of extent of tumour resection and progression free survival while preserving neurological outcome of the patients.
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Affiliation(s)
- Laura Van Hese
- Division of Mass Spectrometry Imaging, Maastricht MultiModal Molecular Imaging (M4I) Institute, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands
- Department of Anaesthesiology, University Hospitals Leuven, 3000, Leuven, Belgium
- Department of Cardiovascular Sciences, KU Leuven, 3000, Leuven, Belgium
| | - Steven De Vleeschouwer
- Neurosurgery Department, University Hospitals Leuven, 3000, Leuven, Belgium
- Laboratory for Experimental Neurosurgery and Neuroanatomy, Department of Neurosciences, Leuven Brain Institute (LBI), 3000, Leuven, Belgium
| | - Tom Theys
- Neurosurgery Department, University Hospitals Leuven, 3000, Leuven, Belgium
- Laboratory for Experimental Neurosurgery and Neuroanatomy, Department of Neurosciences, Leuven Brain Institute (LBI), 3000, Leuven, Belgium
| | - Steffen Rex
- Department of Anaesthesiology, University Hospitals Leuven, 3000, Leuven, Belgium
- Department of Cardiovascular Sciences, KU Leuven, 3000, Leuven, Belgium
| | - Ron M A Heeren
- Division of Mass Spectrometry Imaging, Maastricht MultiModal Molecular Imaging (M4I) Institute, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands
| | - Eva Cuypers
- Division of Mass Spectrometry Imaging, Maastricht MultiModal Molecular Imaging (M4I) Institute, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
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4
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McCracken DJ, Schupper AJ, Lakomkin N, Malcolm J, Painton Bray D, Hadjipanayis CG. Turning on the light for brain tumor surgery: A 5-aminolevulinic acid story. Neuro Oncol 2022; 24:S52-S61. [PMID: 36322101 PMCID: PMC9629477 DOI: 10.1093/neuonc/noac191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To aid surgeons in more complete and safe resection of brain tumors, adjuvant technologies have been developed to improve visualization of target tissue. Fluorescence-guided surgery relies on the use of fluorophores and specific light wavelengths to better delineate tumor tissue, inflammation, and areas of blood-brain barrier breakdown. 5-aminolevulinic acid (5-ALA), the first fluorophore developed specifically for brain tumors, accumulates within tumor cells, improving visualization of tumors both at the core, and infiltrative margin. Here, we describe the background of how 5-ALA integrated into the modern neurosurgery practice, clinical evidence for the current use of 5-ALA, and future directions for its role in neurosurgical oncology. Maximal safe resection remains the standard of care for most brain tumors. Gross total resection of high-grade gliomas (HGGs) is associated with greater overall survival and progression-free survival (PFS) in comparison to subtotal resection or adjuvant treatment therapies alone.1-3 A major challenge neurosurgeons encounter when resecting infiltrative gliomas is identification of the glioma tumor margin to perform a radical resection while avoiding and preserving eloquent regions of the brain. 5-aminolevulinic acid (5-ALA) remains the only optical-imaging agent approved by the FDA for use in glioma surgery and identification of tumor tissue.4 A multicenter randomized, controlled trial revealed that 5-ALA fluorescence-guided surgery (FGS) almost doubled the extent of tumor resection and also improved 6-month PFS.5 In this review, we will highlight the current evidence for use of 5-ALA FGS in brain tumor surgery, as well as discuss the future directions for its use.
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Affiliation(s)
- David J McCracken
- Department of Neurosurgery, Piedmont Healthcare, Atlanta, Georgia, USA
| | - Alexander J Schupper
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, Mount Sinai Health System, New York, New York, USA
| | - Nikita Lakomkin
- Department of Neurosurgery, Mayo Clinic, Rochester, Minnesota, USA
| | - James Malcolm
- Department of Neurosurgery, Emory University, Atlanta, Georgia, USA
| | | | - Constantinos G Hadjipanayis
- Corresponding Author: Constantinos G. Hadjipanayis, MD, PhD, Mount Sinai Union Square, 10 Union Square East, Suite 5E, New York, NY 10003, USA ()
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5
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Bishop KW, Maitland KC, Rajadhyaksha M, Liu JTC. In vivo microscopy as an adjunctive tool to guide detection, diagnosis, and treatment. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:JBO-220032-PER. [PMID: 35478042 PMCID: PMC9043840 DOI: 10.1117/1.jbo.27.4.040601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 04/05/2022] [Indexed: 05/05/2023]
Abstract
SIGNIFICANCE There have been numerous academic and commercial efforts to develop high-resolution in vivo microscopes for a variety of clinical use cases, including early disease detection and surgical guidance. While many high-profile studies, commercialized products, and publications have resulted from these efforts, mainstream clinical adoption has been relatively slow other than for a few clinical applications (e.g., dermatology). AIM Here, our goals are threefold: (1) to introduce and motivate the need for in vivo microscopy (IVM) as an adjunctive tool for clinical detection, diagnosis, and treatment, (2) to discuss the key translational challenges facing the field, and (3) to propose best practices and recommendations to facilitate clinical adoption. APPROACH We will provide concrete examples from various clinical domains, such as dermatology, oral/gastrointestinal oncology, and neurosurgery, to reinforce our observations and recommendations. RESULTS While the incremental improvement and optimization of IVM technologies should and will continue to occur, future translational efforts would benefit from the following: (1) integrating clinical and industry partners upfront to define and maintain a compelling value proposition, (2) identifying multimodal/multiscale imaging workflows, which are necessary for success in most clinical scenarios, and (3) developing effective artificial intelligence tools for clinical decision support, tempered by a realization that complete adoption of such tools will be slow. CONCLUSIONS The convergence of imaging modalities, academic-industry-clinician partnerships, and new computational capabilities has the potential to catalyze rapid progress and adoption of IVM in the next few decades.
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Affiliation(s)
- Kevin W. Bishop
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
- University of Washington, Department of Mechanical Engineering, Seattle, Washington, United States
| | - Kristen C. Maitland
- Texas A&M University, Department of Biomedical Engineering, College Station, Texas, United States
| | - Milind Rajadhyaksha
- Memorial Sloan Kettering Cancer Center, Dermatology Service, New York, New York, United States
| | - Jonathan T. C. Liu
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
- University of Washington, Department of Mechanical Engineering, Seattle, Washington, United States
- University of Washington, Department of Laboratory Medicine and Pathology, Seattle, Washington, United States
- Address all correspondence to Jonathan T.C. Liu,
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6
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Akimoto J, Fukami S, Ichikawa M, Nagai K, Kohno M. Preliminary Report: Rapid Intraoperative Detection of Residual Glioma Cell in Resection Cavity Walls Using a Compact Fluorescence Microscope. J Clin Med 2021; 10:jcm10225375. [PMID: 34830662 PMCID: PMC8620805 DOI: 10.3390/jcm10225375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/12/2021] [Accepted: 11/15/2021] [Indexed: 11/21/2022] Open
Abstract
Objective: The surgical eradication of malignant glioma cells is theoretically impossible. Therefore, reducing the number of remaining tumor cells around the brain–tumor interface (BTI) is crucial for achieving satisfactory clinical results. The usefulness of fluorescence–guided resection for the treatment of malignant glioma was recently reported, but the detection of infiltrating tumor cells in the BTI using a surgical microscope is not realistic. Therefore, we have developed an intraoperative rapid fluorescence cytology system, and exploratorily evaluated its clinical feasibility for the management of malignant glioma. Materials and methods: A total of 25 selected patients with malignant glioma (newly diagnosed: 17; recurrent: 8) underwent surgical resection under photodiagnosis using photosensitizer Talaporfin sodium and a semiconductor laser. Intraoperatively, a crush smear preparation was made from a tiny amount of tumor tissue, and the fluorescence emitted upon 620/660 nm excitation was evaluated rapidly using a compact fluorescence microscope in the operating theater. Results: Fluorescence intensities of tumor tissues measured using a surgical microscope correlated with the tumor cell densities of tissues evaluated by measuring the red fluorescence emitted from the cytoplasm of tumor cells using a fluorescence microscope. A “weak fluorescence” indicated a reduction in the tumor cell density, whereas “no fluorescence” did not indicate the complete eradication of the tumor cells, but indicated that few tumor cells were emitting fluorescence. Conclusion: The rapid intraoperative detection of fluorescence from glioma cells using a compact fluorescence microscope was probably useful to evaluate the presence of tumor cells in the resection cavity walls, and could provide surgical implications for the more complete resection of malignant gliomas.
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Affiliation(s)
- Jiro Akimoto
- Department of Neurosurgery, Kohsei Chuo General Hospital, Tokyo 153-0062, Japan
- Department of Neurosurgery, Tokyo Medical University, Tokyo 160-8402, Japan; (S.F.); (M.I.); (K.N.); (M.K.)
- Correspondence:
| | - Shinjiro Fukami
- Department of Neurosurgery, Tokyo Medical University, Tokyo 160-8402, Japan; (S.F.); (M.I.); (K.N.); (M.K.)
| | - Megumi Ichikawa
- Department of Neurosurgery, Tokyo Medical University, Tokyo 160-8402, Japan; (S.F.); (M.I.); (K.N.); (M.K.)
| | - Kenta Nagai
- Department of Neurosurgery, Tokyo Medical University, Tokyo 160-8402, Japan; (S.F.); (M.I.); (K.N.); (M.K.)
| | - Michihiro Kohno
- Department of Neurosurgery, Tokyo Medical University, Tokyo 160-8402, Japan; (S.F.); (M.I.); (K.N.); (M.K.)
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7
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Schupper AJ, Baron RB, Cheung W, Rodriguez J, Kalkanis SN, Chohan MO, Andersen BJ, Chamoun R, Nahed BV, Zacharia BE, Kennedy J, Moulding HD, Zucker L, Chicoine MR, Olson JJ, Jensen RL, Sherman JH, Zhang X, Price G, Fowkes M, Germano IM, Carter BS, Hadjipanayis CG, Yong RL. 5-Aminolevulinic acid for enhanced surgical visualization of high-grade gliomas: a prospective, multicenter study. J Neurosurg 2021:1-10. [PMID: 34624862 DOI: 10.3171/2021.5.jns21310] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 05/05/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Greater extent of resection (EOR) is associated with longer overall survival in patients with high-grade gliomas (HGGs). 5-Aminolevulinic acid (5-ALA) can increase EOR by improving intraoperative visualization of contrast-enhancing tumor during fluorescence-guided surgery (FGS). When administered orally, 5-ALA is converted by glioma cells into protoporphyrin IX (PPIX), which fluoresces under blue 400-nm light. 5-ALA has been available for use in Europe since 2010, but only recently gained FDA approval as an intraoperative imaging agent for HGG tissue. In this first-ever, to the authors' knowledge, multicenter 5-ALA FGS study conducted in the United States, the primary objectives were the following: 1) assess the diagnostic accuracy of 5-ALA-induced PPIX fluorescence for HGG histopathology across diverse centers and surgeons; and 2) assess the safety profile of 5-ALA FGS, with particular attention to neurological morbidity. METHODS This single-arm, multicenter, prospective study included adults aged 18-80 years with Karnofsky Performance Status (KPS) score > 60 and an MRI diagnosis of suspected new or recurrent resectable HGG. Intraoperatively, 3-5 samples per tumor were taken and their fluorescence status was recorded by the surgeon. Specimens were submitted for histopathological analysis. Patients were followed for 6 weeks postoperatively for adverse events, changes in the neurological exam, and KPS score. Multivariate analyses were performed of the outcomes of KPS decline, EOR, and residual enhancing tumor volume to identify predictive patient and intraoperative variables. RESULTS Sixty-nine patients underwent 5-ALA FGS, providing 275 tumor samples for analysis. PPIX fluorescence had a sensitivity of 96.5%, specificity of 29.4%, positive predictive value (PPV) for HGG histopathology of 95.4%, and diagnostic accuracy of 92.4%. Drug-related adverse events occurred at a rate of 22%. Serious adverse events due to intraoperative neurological injury, which may have resulted from FGS, occurred at a rate of 4.3%. There were 2 deaths unrelated to FGS. Compared to preoperative KPS scores, postoperative KPS scores were significantly lower at 48 hours and 2 weeks but were not different at 6 weeks postoperatively. Complete resection of enhancing tumor occurred in 51.9% of patients. Smaller preoperative tumor volume and use of intraoperative MRI predicted lower residual tumor volume. CONCLUSIONS PPIX fluorescence, as judged by the surgeon, has a high sensitivity and PPV for HGG. 5-ALA was well tolerated in terms of drug-related adverse events, and its application by trained surgeons in FGS for HGGs was not associated with any excess neurological morbidity.
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Affiliation(s)
- Alexander J Schupper
- 1Department of Neurological Surgery, Mount Sinai Health System, New York, New York
| | - Rebecca B Baron
- 1Department of Neurological Surgery, Mount Sinai Health System, New York, New York
| | - William Cheung
- 1Department of Neurological Surgery, Mount Sinai Health System, New York, New York
| | - Jessica Rodriguez
- 1Department of Neurological Surgery, Mount Sinai Health System, New York, New York
| | - Steven N Kalkanis
- 2Department of Neurological Surgery, Henry Ford Medical Center, Detroit, Michigan
| | - Muhammad O Chohan
- 3Department of Neurological Surgery, University of New Mexico Hospital, Albuquerque, New Mexico
| | - Bruce J Andersen
- 4Department of Neurological Surgery, St. Alphonsus Regional Medical Center, Boise, Idaho
| | - Roukoz Chamoun
- 5Department of Neurological Surgery, University of Kansas Medical Center, Kansas City, Kansas
| | - Brian V Nahed
- 6Department of Neurological Surgery, Massachusetts General Hospital, Boston, Massachusetts
| | - Brad E Zacharia
- 7Department of Neurological Surgery, Milton S. Hershey Medical Center, Hershey, Pennsylvania
| | | | - Hugh D Moulding
- 9Department of Neurological Surgery, St. Luke's University Health Network, Bethlehem, Pennsylvania
| | - Lloyd Zucker
- 10Department of Neurological Surgery, Delray Medical Center, Delray Beach, Florida
| | - Michael R Chicoine
- 11Department of Neurological Surgery, Barnes-Jewish Hospital, St. Louis, Missouri
| | - Jeffrey J Olson
- 12Department of Neurological Surgery, Emory University Hospital, Atlanta, Georgia
| | - Randy L Jensen
- 13Department of Neurological Surgery, Huntsman Cancer Institute, Salt Lake City, Utah; and
| | - Jonathan H Sherman
- 14Department of Neurological Surgery, George Washington University Hospital, Washington, DC
| | - Xiangnan Zhang
- 1Department of Neurological Surgery, Mount Sinai Health System, New York, New York
| | - Gabrielle Price
- 1Department of Neurological Surgery, Mount Sinai Health System, New York, New York
| | - Mary Fowkes
- 1Department of Neurological Surgery, Mount Sinai Health System, New York, New York
| | - Isabelle M Germano
- 1Department of Neurological Surgery, Mount Sinai Health System, New York, New York
| | - Bob S Carter
- 6Department of Neurological Surgery, Massachusetts General Hospital, Boston, Massachusetts
| | | | - Raymund L Yong
- 1Department of Neurological Surgery, Mount Sinai Health System, New York, New York
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Reichert D, Erkkilae MT, Gesperger J, Wadiura LI, Lang A, Roetzer T, Woehrer A, Andreana M, Unterhuber A, Wilzbach M, Hauger C, Drexler W, Kiesel B, Widhalm G, Leitgeb RA. Fluorescence Lifetime Imaging and Spectroscopic Co-Validation for Protoporphyrin IX-Guided Tumor Visualization in Neurosurgery. Front Oncol 2021; 11:741303. [PMID: 34595120 PMCID: PMC8476921 DOI: 10.3389/fonc.2021.741303] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 08/24/2021] [Indexed: 12/19/2022] Open
Abstract
Maximal safe resection is a key strategy for improving patient prognosis in the management of brain tumors. Intraoperative fluorescence guidance has emerged as a standard in the surgery of high-grade gliomas. The administration of 5-aminolevulinic acid prior to surgery induces tumor-specific accumulation of protoporphyrin IX, which emits red fluorescence under blue-light illumination. The technology, however, is substantially limited for low-grade gliomas and weakly tumor-infiltrated brain, where low protoporphyrin IX concentrations are outweighed by tissue autofluorescence. In this context, fluorescence lifetime imaging has shown promise to distinguish spectrally overlapping fluorophores. We integrated frequency-domain fluorescence lifetime imaging in a surgical microscope and combined it with spatially registered fluorescence spectroscopy, which can be considered a research benchmark for sensitive protoporphyrin IX detection. Fluorescence lifetime maps and spectra were acquired for a representative set of fresh ex-vivo brain tumor specimens (low-grade gliomas n = 15, high-grade gliomas n = 80, meningiomas n = 41, and metastases n = 35). Combining the fluorescence lifetime with fluorescence spectra unveiled how weak protoporphyrin IX accumulations increased the lifetime respective to tissue autofluorescence. Infiltration zones (4.1ns ± 1.8ns, p = 0.017) and core tumor areas (4.8ns ± 1.3ns, p = 0.040) of low-grade gliomas were significantly distinguishable from non-pathologic tissue (1.6ns ± 0.5ns). Similarly, fluorescence lifetimes for infiltrated and reactive tissue as well as necrotic and core tumor areas were increased for high-grade gliomas and metastasis. Meningioma tumor specimens showed strongly increased lifetimes (12.2ns ± 2.5ns, p = 0.005). Our results emphasize the potential of fluorescence lifetime imaging to optimize maximal safe resection in brain tumors in future and highlight its potential toward clinical translation.
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Affiliation(s)
- David Reichert
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Christian Doppler Laboratory OPTRAMED, Medical University of Vienna, Vienna, Austria
| | - Mikael T Erkkilae
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Johanna Gesperger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Lisa I Wadiura
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Alexandra Lang
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Thomas Roetzer
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Adelheid Woehrer
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Marco Andreana
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Angelika Unterhuber
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Marco Wilzbach
- Advanced Development Microsurgery, Carl Zeiss Meditec AG, Oberkochen, Germany
| | - Christoph Hauger
- Advanced Development Microsurgery, Carl Zeiss Meditec AG, Oberkochen, Germany
| | - Wolfgang Drexler
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Barbara Kiesel
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Georg Widhalm
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Rainer A Leitgeb
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Christian Doppler Laboratory OPTRAMED, Medical University of Vienna, Vienna, Austria
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9
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Lu H, Grygoryev K, Bermingham N, Jansen M, O’Sullivan M, Nunan G, Buckley K, Manley K, Burke R, Andersson-Engels S. Combined autofluorescence and diffuse reflectance for brain tumour surgical guidance: initial ex vivo study results. BIOMEDICAL OPTICS EXPRESS 2021; 12:2432-2446. [PMID: 33996239 PMCID: PMC8086447 DOI: 10.1364/boe.420292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/09/2021] [Accepted: 03/22/2021] [Indexed: 06/12/2023]
Abstract
This ex vivo study was conducted to assess the potential of using a fibre optic probe system based on autofluorescence and diffuse reflectance for tissue differentiation in the brain. A total of 180 optical measurements were acquired from 28 brain specimens (five patients) with eight excitation and emission wavelengths spanning from 300 to 700 nm. Partial least square-linear discriminant analysis (PLS-LDA) was used for tissue discrimination. Leave-one-out cross validation (LOOCV) was then used to evaluate the performance of the classification model. Grey matter was differentiated from tumour tissue with sensitivity of 89.3% and specificity of 92.5%. The variable importance in projection (VIP) derived from the PLS regression was applied to wavelengths selection, and identified the biochemical sources of the detected signals. The initial results of the study were promising and point the way towards a cost-effective, miniaturized hand-held probe for real time and label-free surgical guidance.
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Affiliation(s)
- Huihui Lu
- Biophotonics @ Tyndall, IPIC, Tyndall National Institute, University College Cork, Cork, Ireland
| | - Konstantin Grygoryev
- Biophotonics @ Tyndall, IPIC, Tyndall National Institute, University College Cork, Cork, Ireland
| | - Niamh Bermingham
- Department of Neuropathology, Cork University Hospital, Cork, Ireland
| | - Michael Jansen
- Department of Neuropathology, Cork University Hospital, Cork, Ireland
| | | | - Gerard Nunan
- Stryker, Instruments Innovation Centre, IDA Business and Technology Park, Cork, Ireland
| | - Kevin Buckley
- Stryker, Instruments Innovation Centre, IDA Business and Technology Park, Cork, Ireland
| | - Kevin Manley
- Stryker, Instruments Innovation Centre, IDA Business and Technology Park, Cork, Ireland
| | - Ray Burke
- Biophotonics @ Tyndall, IPIC, Tyndall National Institute, University College Cork, Cork, Ireland
| | - Stefan Andersson-Engels
- Biophotonics @ Tyndall, IPIC, Tyndall National Institute, University College Cork, Cork, Ireland
- Department of Physics, University College Cork, Cork, Ireland
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10
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Lauwerends LJ, van Driel PBAA, Baatenburg de Jong RJ, Hardillo JAU, Koljenovic S, Puppels G, Mezzanotte L, Löwik CWGM, Rosenthal EL, Vahrmeijer AL, Keereweer S. Real-time fluorescence imaging in intraoperative decision making for cancer surgery. Lancet Oncol 2021; 22:e186-e195. [PMID: 33765422 DOI: 10.1016/s1470-2045(20)30600-8] [Citation(s) in RCA: 90] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/23/2020] [Accepted: 09/25/2020] [Indexed: 02/06/2023]
Abstract
Fluorescence-guided surgery is an intraoperative optical imaging method that provides surgeons with real-time guidance for the delineation of tumours. Currently, in phase 1 and 2 clinical trials, evaluation of fluorescence-guided surgery is primarily focused on its diagnostic performance, although the corresponding outcome variables do not inform about the added clinical benefit of fluorescence-guided surgery and are challenging to assess objectively. Nonetheless, the effect of fluorescence-guided surgery on intraoperative decision making is the most objective outcome measurement to assess the clinical value of this imaging method. In this Review, we explore the study designs of existing trials of fluorescence-guided surgery that allow us to extract information on potential changes in intraoperative decision making, such as additional or more conservative resections. On the basis of this analysis, we offer recommendations on how to report changes in intraoperative decision making that result from fluorescence imaging, which is of utmost importance for the widespread clinical implementation of fluorescence-guided surgery.
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Affiliation(s)
- Lorraine J Lauwerends
- Department of Otorhinolaryngology, Head and Neck Surgery, Erasmus University Medical Center, Rotterdam, Netherlands; Erasmus Medical Center Cancer Institute, Erasmus University Medical Center, Rotterdam, Netherlands
| | | | - Robert J Baatenburg de Jong
- Department of Otorhinolaryngology, Head and Neck Surgery, Erasmus University Medical Center, Rotterdam, Netherlands; Erasmus Medical Center Cancer Institute, Erasmus University Medical Center, Rotterdam, Netherlands
| | - José A U Hardillo
- Department of Otorhinolaryngology, Head and Neck Surgery, Erasmus University Medical Center, Rotterdam, Netherlands; Erasmus Medical Center Cancer Institute, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Senada Koljenovic
- Department of Pathology, Erasmus University Medical Center, Rotterdam, Netherlands; Erasmus Medical Center Cancer Institute, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Gerwin Puppels
- Department of Dermatology, Erasmus University Medical Center, Rotterdam, Netherlands; Erasmus Medical Center Cancer Institute, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Laura Mezzanotte
- Department of Radiology and Nuclear Medicine, Erasmus University Medical Center, Rotterdam, Netherlands; Erasmus Medical Center Cancer Institute, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Clemens W G M Löwik
- Department of Radiology and Nuclear Medicine, Erasmus University Medical Center, Rotterdam, Netherlands; Erasmus Medical Center Cancer Institute, Erasmus University Medical Center, Rotterdam, Netherlands; Department of Oncology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland; Ludwig Institute for Cancer Research, Lausanne, Switzerland
| | - Eben L Rosenthal
- Department of Otolaryngology, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Stijn Keereweer
- Department of Otorhinolaryngology, Head and Neck Surgery, Erasmus University Medical Center, Rotterdam, Netherlands; Erasmus Medical Center Cancer Institute, Erasmus University Medical Center, Rotterdam, Netherlands.
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11
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Liu JTC, Glaser AK, Bera K, True LD, Reder NP, Eliceiri KW, Madabhushi A. Harnessing non-destructive 3D pathology. Nat Biomed Eng 2021; 5:203-218. [PMID: 33589781 PMCID: PMC8118147 DOI: 10.1038/s41551-020-00681-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 12/17/2020] [Indexed: 02/08/2023]
Abstract
High-throughput methods for slide-free three-dimensional (3D) pathological analyses of whole biopsies and surgical specimens offer the promise of modernizing traditional histology workflows and delivering improvements in diagnostic performance. Advanced optical methods now enable the interrogation of orders of magnitude more tissue than previously possible, where volumetric imaging allows for enhanced quantitative analyses of cell distributions and tissue structures that are prognostic and predictive. Non-destructive imaging processes can simplify laboratory workflows, potentially reducing costs, and can ensure that samples are available for subsequent molecular assays. However, the large size of the feature-rich datasets that they generate poses challenges for data management and computer-aided analysis. In this Perspective, we provide an overview of the imaging technologies that enable 3D pathology, and the computational tools-machine learning, in particular-for image processing and interpretation. We also discuss the integration of various other diagnostic modalities with 3D pathology, along with the challenges and opportunities for clinical adoption and regulatory approval.
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Affiliation(s)
- Jonathan T C Liu
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA.
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA.
- Department of Bioengineering, University of Washington, Seattle, WA, USA.
| | - Adam K Glaser
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
| | - Kaustav Bera
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Lawrence D True
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Nicholas P Reder
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Kevin W Eliceiri
- Department of Medical Physics, University of Wisconsin, Madison, WI, USA.
- Department of Biomedical Engineering, University of Wisconsin, Madison, WI, USA.
- Morgridge Institute for Research, Madison, WI, USA.
| | - Anant Madabhushi
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.
- Louis Stokes Cleveland Veterans Administration Medical Center, Cleveland, OH, USA.
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12
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Labuschagne J. 5-aminolevulinic acid-guided surgery for focal pediatric brainstem gliomas: A preliminary study. Surg Neurol Int 2020; 11:334. [PMID: 33194268 PMCID: PMC7656004 DOI: 10.25259/sni_246_2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 08/28/2020] [Indexed: 12/22/2022] Open
Abstract
Background: There is a growing body of literature supporting the use of 5-aminolevulinic acid (5-ALA) in the pediatric population, however, its use is still considered “off label” in this setting. In this retrospective study, we report our experience using 5-ALA in pediatric patients with focal brainstem gliomas (BSGs). Methods: Patients younger than 16 years presenting with a newly diagnosed BSG that was focal in nature were considered suitable for treatment with 5-ALA-assisted surgery. Exclusion criteria included MRI features suggestive of a diffuse intrinsic pontine glioma. A single dose of 5-ALA was administered preoperatively. Intraoperative fluorescence was recorded as “solid,” “vague,” or “none.” The effectiveness of the fluorescence was graded as “helpful” or “unhelpful.” Results: Eight patients underwent 5-ALA-assisted surgery. There were four tumors located in the pons, two midbrain tumors, and two cervicomedullary tumors. Histological analysis demonstrated three diffuse astrocytomas, three pilocytic astrocytomas, and two anaplastic astrocytomas. Solid fluorescence was found in three of the eight cases, vague fluorescence was found in two cases, and no fluorescence was found in three cases. Fluorescence was useful in 3 (37%) cases. No patients experienced any complications attributable to the administration of the 5-ALA. Conclusion: With a total fluorescence rate of 62.5% but a subjectively assessed “usefulness” rate of only 37.5%, the role of 5-ALA in BSG surgery is limited. Given the toxicological safety, however, of the agent, caution is perhaps needed before dismissing the use of 5-ALA entirely.
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Affiliation(s)
- Jason Labuschagne
- Department of Paediatric Neurosurgery, Nelson Mandela Childrens Hospital, Parktown, Johanessburg, South Africa
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13
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Abstract
Fluorescence-guided surgery provides surgeons with improved visualization of tumor tissue in the operating room to allow for maximal safe resection of brain tumors. Multiple fluorescent agents have been studied for fluorescence-guided surgery. Both nontargeted and targeted fluorescent agents are currently being used for glioblastoma multiforme visualization and resection. Fluorescence detection in the visible light or near infrared spectrum is possible. Visualization device advancements have permitted greater detection of fluorescence down to the cellular level, which may provide even greater ability for the neurosurgeon to resect tumors.
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Affiliation(s)
- Alexander J Schupper
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, Mount Sinai Health System, New York, NY, USA
| | - Constantinos Hadjipanayis
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, Mount Sinai Health System, New York, NY, USA; Department of Neurosurgery, Mount Sinai Beth Israel, New York, NY, USA.
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14
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Labuschagne JJ. 5-Aminolevulinic Acid-Guided Surgery for Recurrent Supratentorial Pediatric Neoplasms. World Neurosurg 2020; 141:e763-e769. [PMID: 32526366 DOI: 10.1016/j.wneu.2020.06.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/30/2020] [Accepted: 06/02/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND The use of 5-aminolevulinic acid (5-ALA) in pediatric neuro-oncology is considered off-label, and little data are available on its use in tumor recurrence surgery. Here we present our experience with 5-ALA fluorescence-guided surgery for recurrent supratentorial tumors in the pediatric population. METHODS Eleven pediatric patients presenting with recurrence of a supratentorial high-grade malignancy (5 glioblastoma [GBM], 6 non-GBM) underwent 5-ALA-assisted surgery. Biopsy specimens were obtained from pathological and normal-appearing areas of the tumor margin. RESULTS From the margin of the tumor displaying solid fluorescence, a total of 36 samples were obtained. All of these histological samples were found to harbor tumor cells. From areas of vague enhancement, a total of 49 histological samples were taken, of which 38 samples (77%) harbored tumor cells. There was no significant difference in the percentage of biopsy-positive vague fluorescent areas between the GBM cases (80%) and non-GBM cases (75%). A total of 59 biopsy specimens were taken from the tumor margin that appeared completely negative for fluorescence. On analysis, 24 (40.7%) of these specimens demonstrated tumor cells. There was no significant difference in the number of false-negative biopsies between the GBM group (40%) and the non-GBM group (41%). CONCLUSIONS The positive predictive value of solid fluorescence is high in recurrent disease but is substantially lower in areas of vague fluorescence. The rate of false-negative fluorescence is high. 5-ALA should be considered as an adjuvant in revision surgery with the aforementioned caveats in mind.
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Affiliation(s)
- Jason John Labuschagne
- Department of Neurosurgery, University of the Witwatersrand, Johannesburg and Department of Paediatric Neurosurgery, Nelson Mandela Children's Hospital, Johannesburg, South Africa.
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15
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Fujita Y, Wei L, Cimino PJ, Liu JTC, Sanai N. Video-Mosaicked Handheld Dual-Axis Confocal Microscopy of Gliomas: An ex vivo Feasibility Study in Humans. Front Oncol 2020; 10:1674. [PMID: 32974207 PMCID: PMC7482651 DOI: 10.3389/fonc.2020.01674] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/29/2020] [Indexed: 01/07/2023] Open
Abstract
Background Intraoperative confocal microscopy can enable high-resolution cross-sectional imaging of intact tissues as a non-invasive real-time alternative to gold-standard histology. However, all current means of intraoperative confocal microscopy are hindered by a limited field of view (FOV), presenting a challenge for evaluating gliomas, which are highly heterogeneous. Objective This study explored the use of image mosaicking with handheld dual-axis confocal (DAC) microscopy of fresh human glioma specimens. Methods In this preliminary technical feasibility study, fresh human glioma specimens from 6 patients were labeled with a fast-acting topical stain (acridine orange) and imaged using a newly developed DAC microscope prototype. Results In comparison to individual image frames with small fields of view, mosaicked images from a DAC microscope correlate better with gold-standard H&E-stained histology images, including the ability to visualize gradual transitions from areas of dense cellularity to sparse cellularity within the tumor. Conclusion LS-DAC microscopy provides high-resolution, high-contrast images of glioma tissues that agree with corresponding H&E histology. Compared with individual image frames, mosaicked images provide more accurate representations of the overall cytoarchitecture of heterogeneous glioma tissues. Further investigation is needed to evaluate the ability of high-resolution mosaicked microscopy to improve the extent of glioma resection and patient outcomes.
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Affiliation(s)
- Yoko Fujita
- Ivy Brain Tumor Center, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, United States
| | - Linpeng Wei
- Department of Mechanical Engineering, University of Washington, Seattle, WA, United States
| | - Patrick J Cimino
- Department of Pathology, University of Washington, Seattle, WA, United States
| | - Jonathan T C Liu
- Department of Mechanical Engineering, University of Washington, Seattle, WA, United States.,Department of Pathology, University of Washington, Seattle, WA, United States.,Department of Bioengineering, University of Washington, Seattle, WA, United States
| | - Nader Sanai
- Ivy Brain Tumor Center, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, United States.,Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, United States
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16
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Yin C, Wei L, Kose K, Glaser AK, Peterson G, Rajadhyaksha M, Liu JT. Real-time video mosaicking to guide handheld in vivo microscopy. JOURNAL OF BIOPHOTONICS 2020; 13:e202000048. [PMID: 32246558 PMCID: PMC7969124 DOI: 10.1002/jbio.202000048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 03/16/2020] [Accepted: 03/24/2020] [Indexed: 05/05/2023]
Abstract
Handheld and endoscopic optical-sectioning microscopes are being developed for noninvasive screening and intraoperative consultation. Imaging a large extent of tissue is often desired, but miniature in vivo microscopes tend to suffer from limited fields of view. To extend the imaging field during clinical use, we have developed a real-time video mosaicking method, which allows users to efficiently survey larger areas of tissue. Here, we modified a previous post-processing mosaicking method so that real-time mosaicking is possible at >30 frames/second when using a device that outputs images that are 400 × 400 pixels in size. Unlike other real-time mosaicking methods, our strategy can accommodate image rotations and deformations that often occur during clinical use of a handheld microscope. We perform a feasibility study to demonstrate that the use of real-time mosaicking is necessary to enable efficient sampling of a desired imaging field when using a handheld dual-axis confocal microscope.
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Affiliation(s)
- Chengbo Yin
- University of Washington, Department of Mechanical Engineering, Seattle, WA, 98195, USA
| | - Linpeng Wei
- University of Washington, Department of Mechanical Engineering, Seattle, WA, 98195, USA
| | - Kivanc Kose
- Memorial Sloan-Kettering Cancer Center, Dermatology Service, New York, NY, 10021, USA
| | - Adam K. Glaser
- University of Washington, Department of Mechanical Engineering, Seattle, WA, 98195, USA
| | - Gary Peterson
- Memorial Sloan-Kettering Cancer Center, Dermatology Service, New York, NY, 10021, USA
| | - Milind Rajadhyaksha
- Memorial Sloan-Kettering Cancer Center, Dermatology Service, New York, NY, 10021, USA
| | - Jonathan T.C. Liu
- University of Washington, Department of Mechanical Engineering, Seattle, WA, 98195, USA
- University of Washington School of Medicine, Department of Pathology, Seattle, WA 98195, USA
- University of Washington, Department of Bioengineering, Seattle, WA 98195, USA
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