1
|
Mischkulnig M, Roetzer-Pejrimovsky T, Lötsch-Gojo D, Kastner N, Bruckner K, Prihoda R, Lang A, Martinez-Moreno M, Furtner J, Berghoff A, Woehrer A, Berger W, Widhalm G, Kiesel B. Heme Biosynthesis Factors and 5-ALA Induced Fluorescence: Analysis of mRNA and Protein Expression in Fluorescing and Non-fluorescing Gliomas. Front Med (Lausanne) 2022; 9:907442. [PMID: 35665365 PMCID: PMC9157484 DOI: 10.3389/fmed.2022.907442] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 04/21/2022] [Indexed: 11/13/2022] Open
Abstract
Objective The intraoperative visualization of adult-type diffuse gliomas with 5-aminolevulinic acid (5-ALA) induced fluorescence is widely used in the neurosurgical field. While visible 5-ALA induced fluorescence is found in the majority of high-grade gliomas, most low-grade gliomas lack visible fluorescence during surgery. Recently, the heme biosynthesis pathway was identified as crucial influencing factor for presence of visible fluorescence since it metabolizes 5-ALA to fluorescing Protoporphyrin IX (PpIX). However, the exact alterations within the heme biosynthesis pathway resulting in visible 5-ALA induced fluorescence in gliomas are still unclear. The aim of the present study was thus to compare the mRNA and protein expression of promising intramitochondrial heme biosynthesis enzymes/transporters in glioma tissue samples of different fluorescence behavior. Methods A total of 19 strongly fluorescing and 21 non-fluorescing tissue samples from neurosurgical adult-type diffuse gliomas (WHO grades II-IV) were included in the current analysis. In these samples, we investigated the mRNA expression by quantitative real time PCR and protein expression using immunohistochemistry of the intramitochondrial heme biosynthesis enzymes Coproporphyrinogen Oxidase (CPOX), Protoporphyrinogen Oxidase (PPOX), Ferrochelatase (FECH), and the transporter ATP-binding Cassette Subfamily B Member 2 (ABCG2). Results Regarding mRNA expression analysis, we found a significantly decreased ABCG2 expression in fluorescing specimens compared to non-fluorescing samples (p = 0.001), whereas no difference in CPOX, PPOX and FECH was present. With respect to protein expression, significantly higher levels of CPOX (p = 0.005), PPOX (p < 0.01) and FECH (p = 0.003) were detected in fluorescing samples. Similar to mRNA expression analysis, the protein expression of ABCG2 (p = 0.001) was significantly lower in fluorescing samples. Conclusion Distinct alterations of the analyzed heme biosynthesis factors were found primarily on protein level. Our data indicate that heme biosynthesis pathway activity in general is enhanced in fluorescing gliomas with upregulation of PpIX generating enzymes and decreased ABCG2 mediated PpIX efflux outweighing the also increased further metabolization of PpIX to heme. Intramitochondrial heme biosynthesis factors thus constitute promising pharmacological targets to optimize intraoperative 5-ALA fluorescence visualization of usually non-fluorescing tumors such as low-grade gliomas.
Collapse
Affiliation(s)
- Mario Mischkulnig
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
- Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University of Vienna, Vienna, Austria
| | - Thomas Roetzer-Pejrimovsky
- Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University of Vienna, Vienna, Austria
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Daniela Lötsch-Gojo
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
- Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University of Vienna, Vienna, Austria
| | - Nina Kastner
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Katharina Bruckner
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Romana Prihoda
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
- Department of Neurosurgery, University Hospital of St. Poelten, Karl Landsteiner University of Health Sciences, St. Poelten, Austria
| | - Alexandra Lang
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
- Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University of Vienna, Vienna, Austria
| | | | - Julia Furtner
- Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University of Vienna, Vienna, Austria
- Department of Radiology and Nuclear Medicine, Medical University of Vienna, Vienna, Austria
| | - Anna Berghoff
- Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University of Vienna, Vienna, Austria
- Clinical Division of Oncology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Adelheid Woehrer
- Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University of Vienna, Vienna, Austria
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Walter Berger
- Institute of Cancer Research, Medical University of Vienna, Vienna, Austria
| | - Georg Widhalm
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
- Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University of Vienna, Vienna, Austria
| | - Barbara Kiesel
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
- Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University of Vienna, Vienna, Austria
- *Correspondence: Barbara Kiesel,
| |
Collapse
|
2
|
Analysis of corticosteroid and antiepileptic drug treatment effects on heme biosynthesis mRNA expression in lower-grade gliomas: potential implications for 5-ALA metabolization. Photodiagnosis Photodyn Ther 2022; 38:102755. [PMID: 35149260 DOI: 10.1016/j.pdpdt.2022.102755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 01/22/2022] [Accepted: 02/07/2022] [Indexed: 11/24/2022]
Abstract
OBJECTIVES Intraoperative visualization of gliomas with 5-aminolevulinic acid (5-ALA) induced fluorescence constitutes a powerful technique. While visible fluorescence is typically observed in high-grade gliomas, fluorescence is considerably less common in lower-grade gliomas (LGGs) WHO grade II&III. Whereas the exact mechanisms determining fluorescence in LGGs are not fully understood, metabolization of non-fluorescent 5-ALA to fluorescent Protoporphyrin IX by specific heme biosynthesis enzymes/transporters has been identified as relevant mechanism influencing fluorescence behavior. Furthermore, recent in-vitro studies have suggested preoperative treatment with corticosteroids and anti-epileptic drugs (AED) as potential factors influencing 5-ALA induced fluorescence. METHODS The goal of this study was thus to investigate the effect of preoperative corticosteroid/AED treatment on heme biosynthesis mRNA expression in a clinically relevant patient population. For this purpose, we analyzed the mRNA expression levels of specific heme biosynthesis factors including ALAD, HMBS, UROS, UROD, CPOX, PPOX, FECH, ABCB6, ACG2, SLC15A1 and SLC15A2, ABCB1, ABCB10 in a cohort of LGGs from "The Cancer Genome Atlas". RESULTS Altogether, 403 patients with available data on preoperative corticosteroid/AED treatment and heme biosynthesis mRNA expression were identified. Regarding corticosteroid treatment, no significant differences in expression of any of the 11 investigated heme biosynthesis factors were found. In contrast, a marginal yet statistically significant increase in SLC15A1 levels and decrease in ABCB6 levels were observed in patients with preoperative AED treatment. CONCLUSION While no significant differences in heme biosynthesis mRNA expression were observed according to preoperative corticosteroid treatment, changes in SLC15A1 as well as ABCB6 expression were detected in patients treated with AED. However, since these alterations were minor and have opposing effects on 5-ALA metabolization, our findings do not support a distinct effect of AED and corticosteroid treatment on heme biosynthesis regulation in LGGs.
Collapse
|
3
|
Kaneko S, Suero Molina E, Sporns P, Schipmann S, Black D, Stummer W. Fluorescence real-time kinetics of protoporphyrin IX after 5-ALA administration in low-grade glioma. J Neurosurg 2021; 136:9-15. [PMID: 34144512 DOI: 10.3171/2020.10.jns202881] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 10/30/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE 5-Aminolevulinic acid (5-ALA) induces fluorescence in high-grade glioma (HGG), which is used for resection. However, the value of 5-ALA-induced fluorescence in low-grade glioma (LGG) is unclear. Time dependency and time kinetics have not yet been investigated. The purpose of this study was to investigate real-time kinetics of protoporphyrin IX (PpIX) in LGG based on hyperspectral fluorescence-based measurements and identify factors that predict fluorescence. METHODS Patients with grade II gliomas and imaging from which HGGs could not be completely ruled out received 5-ALA at 20 mg/kg body weight 4 hours prior to surgery. Fluorescence intensity (FI) and PpIX concentration (CPpIX) were measured in tumor tissue utilizing a hyperspectral camera. Apparent diffusion coefficient (ADC)-based tumor cell density, Ki-67/MIB-1 index, chromosomal 1p/19q codeletion, and 18F-fluoroethyl-l-tyrosine (18F-FET) PET values and their role for predicting fluorescence were evaluated. RESULTS Eighty-one biopsies from 25 patients were included. Tissues with fluorescence demonstrated FI and CPpIX maxima between 7 and 8 hours after administration. When visible fluorescence was observed, peaks of FI and CPpIX were observed within this 7- to 8-hour time frame, regardless of any MRI gadolinium contrast enhancement. Gadolinium enhancement (p = 0.008), Ki-67/MIB-1 index (p < 0.001), 18F-FET PET uptake ratio (p = 0.004), and ADC-based tumor cellularity (p = 0.017) significantly differed between fluorescing and nonfluorescing tissue, but not 1p/19q codeletions. Logistic regression demonstrated that 18F-FET PET uptake and Ki-67/MIB-1 index were independently related to fluorescence. CONCLUSIONS This study reports a fluorescence-based assessment of CPpIX in human LGG tissues related to 18F-FET PET uptake and Ki-67/MIB-1. As in HGGs, fluorescence in LGGs peaked between 7 and 8 hours after 5-ALA application, which has consequences for the timing of administration.
Collapse
Affiliation(s)
- Sadahiro Kaneko
- 1Department of Neurosurgery, University Hospital of Münster, Germany.,2Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Eric Suero Molina
- 1Department of Neurosurgery, University Hospital of Münster, Germany
| | - Peter Sporns
- 3Department of Neuroradiology, Clinic of Radiology and Nuclear Medicine, University Hospital Basel, Switzerland.,4Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - David Black
- 5Carl Zeiss Meditec AG, Oberkochen, Germany; and.,6University of British Columbia, Vancouver, British Columbia, Canada
| | - Walter Stummer
- 1Department of Neurosurgery, University Hospital of Münster, Germany
| |
Collapse
|
4
|
Checa-Chavarria E, Rivero-Buceta E, Sanchez Martos MA, Martinez Navarrete G, Soto-Sánchez C, Botella P, Fernández E. Development of a Prodrug of Camptothecin for Enhanced Treatment of Glioblastoma Multiforme. Mol Pharm 2021; 18:1558-1572. [PMID: 33645231 PMCID: PMC8482753 DOI: 10.1021/acs.molpharmaceut.0c00968] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
![]()
A novel therapeutic approach for
glioblastoma multiforme (GBM)
therapy has been carried out through in vitro and in vivo testing by using the prodrug camptothecin-20-O-(5-aminolevulinate) (CPT-ALA). The incorporation of ALA
to CPT may promote uptake of the cytotoxic molecule by glioblastoma
cells where the heme synthesis pathway is active, improving the therapeutic
action and reducing the side effects over healthy tissue. The antitumor
properties of CPT-ALA have been tested on different GBM cell lines
(U87, U251, and C6) as well as in an orthotopic GBM model in rat,
where potential toxicity in central nervous system cells was analyzed. In vitro results indicated no significant differences in
the cytotoxic effect over the different GBM cell lines for CPT and
CPT-ALA, albeit cell mortality induced by CPT over normal cell lines
was significantly higher than CPT-ALA. Moreover, intracranial GBM
in rat was significantly reduced (30% volume) with 2 weeks of CPT-ALA
treatment with no significant side effects or alterations to the well-being
of the animals tested. 5-ALA moiety enhances CPT diffusion into tumors
due to solubility improvement and its metabolic-based targeting, increasing
the CPT cytotoxic effect on malignant cells while reducing CPT diffusion
to other proliferative healthy tissue. We demonstrate that CPT-ALA
blocks proliferation of GBM cells, reducing the infiltrative capacity
of GBM and promoting the success of surgical removal, which improves
life expectancy by reducing tumor recurrence.
Collapse
Affiliation(s)
- Elisa Checa-Chavarria
- Institute of Bioengineering, Universidad Miguel Hernández, Elche, Spain and Centre for Network Biomedical Research (CIBER-BBN), Avenida de la Universidad s/n, 03202 Elche, Spain
| | - Eva Rivero-Buceta
- Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avenida de los Naranjos s/n, 46022 Valencia, Spain
| | - Miguel Angel Sanchez Martos
- Institute of Bioengineering, Universidad Miguel Hernández, Elche, Spain and Centre for Network Biomedical Research (CIBER-BBN), Avenida de la Universidad s/n, 03202 Elche, Spain
| | - Gema Martinez Navarrete
- Institute of Bioengineering, Universidad Miguel Hernández, Elche, Spain and Centre for Network Biomedical Research (CIBER-BBN), Avenida de la Universidad s/n, 03202 Elche, Spain
| | - Cristina Soto-Sánchez
- Institute of Bioengineering, Universidad Miguel Hernández, Elche, Spain and Centre for Network Biomedical Research (CIBER-BBN), Avenida de la Universidad s/n, 03202 Elche, Spain
| | - Pablo Botella
- Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avenida de los Naranjos s/n, 46022 Valencia, Spain
| | - Eduardo Fernández
- Institute of Bioengineering, Universidad Miguel Hernández, Elche, Spain and Centre for Network Biomedical Research (CIBER-BBN), Avenida de la Universidad s/n, 03202 Elche, Spain
| |
Collapse
|
5
|
Traylor JI, Pernik MN, Sternisha AC, McBrayer SK, Abdullah KG. Molecular and Metabolic Mechanisms Underlying Selective 5-Aminolevulinic Acid-Induced Fluorescence in Gliomas. Cancers (Basel) 2021; 13:cancers13030580. [PMID: 33540759 PMCID: PMC7867275 DOI: 10.3390/cancers13030580] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 01/22/2021] [Accepted: 01/26/2021] [Indexed: 02/06/2023] Open
Abstract
Simple Summary 5-aminolevulinic acid (5-ALA) is a medication that produces fluorescence in certain cancers, which enables surgeons to visualize tumor margins during surgery. Gliomas are brain tumors that can be difficult to fully resect due to their infiltrative nature. In this review we explored what is known about the mechanism of 5-ALA, recent discoveries that increase our understanding of that mechanism, and potential targets to increase fluorescence in lower grade gliomas. Abstract 5-aminolevulinic acid (5-ALA) is a porphyrin precursor in the heme synthesis pathway. When supplied exogenously, certain cancers consume 5-ALA and convert it to the fluorogenic metabolite protoporphyrin IX (PpIX), causing tumor-specific tissue fluorescence. Preoperative administration of 5-ALA is used to aid neurosurgical resection of high-grade gliomas such as glioblastoma, allowing for increased extent of resection and progression free survival for these patients. A subset of gliomas, especially low-grade tumors, do not accumulate PpIX intracellularly or readily fluoresce upon 5-ALA administration, making gross total resection difficult to achieve in diffuse lesions. We review existing literature on 5-ALA metabolism and PpIX accumulation to explore potential mechanisms of 5-ALA-induced glioma tissue fluorescence. Targeting the heme synthesis pathway and understanding its dysregulation in malignant tissues could aid the development of adjunct therapies to increase intraoperative fluorescence after 5-ALA treatment.
Collapse
Affiliation(s)
- Jeffrey I. Traylor
- Department of Neurological Surgery, University of Texas Southwestern Medical Center, Dallas, TX 75235, USA; (J.I.T.); (M.N.P.)
| | - Mark N. Pernik
- Department of Neurological Surgery, University of Texas Southwestern Medical Center, Dallas, TX 75235, USA; (J.I.T.); (M.N.P.)
| | - Alex C. Sternisha
- Children’s Medical Center Research Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA;
| | - Samuel K. McBrayer
- Children’s Medical Center Research Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA;
- Correspondence: (S.K.M.); (K.G.A.); Tel.: +1-(214)-648-3730 (S.K.M.); +1-(214)-645-2300 (K.G.A.)
| | - Kalil G. Abdullah
- Department of Neurological Surgery, University of Texas Southwestern Medical Center, Dallas, TX 75235, USA; (J.I.T.); (M.N.P.)
- Correspondence: (S.K.M.); (K.G.A.); Tel.: +1-(214)-648-3730 (S.K.M.); +1-(214)-645-2300 (K.G.A.)
| |
Collapse
|
6
|
Ma L, Fei B. Comprehensive review of surgical microscopes: technology development and medical applications. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-200292VRR. [PMID: 33398948 PMCID: PMC7780882 DOI: 10.1117/1.jbo.26.1.010901] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 12/04/2020] [Indexed: 05/06/2023]
Abstract
SIGNIFICANCE Surgical microscopes provide adjustable magnification, bright illumination, and clear visualization of the surgical field and have been increasingly used in operating rooms. State-of-the-art surgical microscopes are integrated with various imaging modalities, such as optical coherence tomography (OCT), fluorescence imaging, and augmented reality (AR) for image-guided surgery. AIM This comprehensive review is based on the literature of over 500 papers that cover the technology development and applications of surgical microscopy over the past century. The aim of this review is threefold: (i) providing a comprehensive technical overview of surgical microscopes, (ii) providing critical references for microscope selection and system development, and (iii) providing an overview of various medical applications. APPROACH More than 500 references were collected and reviewed. A timeline of important milestones during the evolution of surgical microscope is provided in this study. An in-depth technical overview of the optical system, mechanical system, illumination, visualization, and integration with advanced imaging modalities is provided. Various medical applications of surgical microscopes in neurosurgery and spine surgery, ophthalmic surgery, ear-nose-throat (ENT) surgery, endodontics, and plastic and reconstructive surgery are described. RESULTS Surgical microscopy has been significantly advanced in the technical aspects of high-end optics, bright and shadow-free illumination, stable and flexible mechanical design, and versatile visualization. New imaging modalities, such as hyperspectral imaging, OCT, fluorescence imaging, photoacoustic microscopy, and laser speckle contrast imaging, are being integrated with surgical microscopes. Advanced visualization and AR are being added to surgical microscopes as new features that are changing clinical practices in the operating room. CONCLUSIONS The combination of new imaging technologies and surgical microscopy will enable surgeons to perform challenging procedures and improve surgical outcomes. With advanced visualization and improved ergonomics, the surgical microscope has become a powerful tool in neurosurgery, spinal, ENT, ophthalmic, plastic and reconstructive surgeries.
Collapse
Affiliation(s)
- Ling Ma
- University of Texas at Dallas, Department of Bioengineering, Richardson, Texas, United States
| | - Baowei Fei
- University of Texas at Dallas, Department of Bioengineering, Richardson, Texas, United States
- University of Texas Southwestern Medical Center, Department of Radiology, Dallas, Texas, United States
| |
Collapse
|
7
|
Mischkulnig M, Kiesel B, Lötsch D, Roetzer T, Borkovec M, Wadiura LI, Mercea PA, Jaklin FJ, Hervey-Jumper S, Roessler K, Berger MS, Widhalm G, Erhart F. TCGA mRNA Expression Analysis of the Heme Biosynthesis Pathway in Diffusely Infiltrating Gliomas: A Comparison of Typically 5-ALA Fluorescent and Non-Fluorescent Gliomas. Cancers (Basel) 2020; 12:cancers12082043. [PMID: 32722247 PMCID: PMC7466145 DOI: 10.3390/cancers12082043] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/20/2020] [Accepted: 07/22/2020] [Indexed: 12/13/2022] Open
Abstract
5-Aminolevulinic acid (5-ALA) is a fluorescent dye that after metabolization to Protoporphyrin IX (PpIX) by the heme biosynthesis pathway typically leads to visible fluorescence in WHO grade IV but not grade II gliomas. The exact mechanism for high PpIX levels in WHO grade IV gliomas and low PpIX levels in WHO grade II gliomas is not fully clarified. To detect relevant changes in mRNA expression, we performed an in-silico analysis of WHO grade II and IV glioma sequencing datasets provided by The Cancer Genome Atlas (TCGA) to investigate mRNA expression levels of relevant heme biosynthesis genes: Solute Carrier Family 15 Member 1 and 2 (SLC15A1 and SLC15A2), Aminolevulinate-Dehydratase (ALAD), Hydroxymethylbilane-Synthase (HMBS), Uroporphyrinogen-III-Synthase (UROS), Uroporphyrinogen-Decarboxylase (UROD), Coproporphyrinogen-Oxidase (CPOX), Protoporphyrinogen-Oxidase (PPOX), ATP-binding Cassette Subfamily B Member 6 (ABCB6)/G Member 2 (ABCG2) and Ferrochelatase (FECH). Altogether, 258 WHO grade II and 166 WHO grade IV samples were investigated. The mRNA expression levels showed significant differences in 8 of 11 examined genes between WHO grade II and IV gliomas. Significant differences in mRNA expression included increases of HMBS, UROD, FECH and PPOX as well as decreases of SLC15A2, ALAD, UROS and ABCB6 in WHO IV gliomas. Since the majority of changes was found in directions that might actually impair PpIX accumulation in WHO grade IV gliomas, additional studies are needed to analyze the corresponding factors of the heme biosynthesis also on protein level.
Collapse
Affiliation(s)
- Mario Mischkulnig
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
- Comprehensive Cancer Center-Central Nervous System Tumours Unit, Medical University Vienna, 1090 Vienna, Austria;
| | - Barbara Kiesel
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
- Comprehensive Cancer Center-Central Nervous System Tumours Unit, Medical University Vienna, 1090 Vienna, Austria;
| | - Daniela Lötsch
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
- Comprehensive Cancer Center-Central Nervous System Tumours Unit, Medical University Vienna, 1090 Vienna, Austria;
| | - Thomas Roetzer
- Comprehensive Cancer Center-Central Nervous System Tumours Unit, Medical University Vienna, 1090 Vienna, Austria;
- Department of Neurology, Division of Neuropathology and Neurochemistry, Medical University Vienna, 1090 Vienna, Austria
| | - Martin Borkovec
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
- Department of Statistics, Ludwig-Maximilians-University, 80539 Munich, Germany
| | - Lisa I. Wadiura
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
- Comprehensive Cancer Center-Central Nervous System Tumours Unit, Medical University Vienna, 1090 Vienna, Austria;
| | - Petra A. Mercea
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
- Comprehensive Cancer Center-Central Nervous System Tumours Unit, Medical University Vienna, 1090 Vienna, Austria;
| | - Florian J. Jaklin
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
| | - Shawn Hervey-Jumper
- Department of Neurological Surgery, University of California, San Francisco, CA 94143, USA; (S.H.-J.); (M.S.B.)
| | - Karl Roessler
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
- Comprehensive Cancer Center-Central Nervous System Tumours Unit, Medical University Vienna, 1090 Vienna, Austria;
| | - Mitchel S. Berger
- Department of Neurological Surgery, University of California, San Francisco, CA 94143, USA; (S.H.-J.); (M.S.B.)
| | - Georg Widhalm
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
- Comprehensive Cancer Center-Central Nervous System Tumours Unit, Medical University Vienna, 1090 Vienna, Austria;
- Correspondence: ; Tel.: +43-1-40400-45650
| | - Friedrich Erhart
- Department of Neurosurgery, Medical University Vienna, 1090 Vienna, Austria; (M.M.); (B.K.); (D.L.); (M.B.); (L.I.W.); (P.A.M.); (F.J.J.); (K.R.); (F.E.)
- Comprehensive Cancer Center-Central Nervous System Tumours Unit, Medical University Vienna, 1090 Vienna, Austria;
| |
Collapse
|
8
|
Belykh E, Shaffer KV, Lin C, Byvaltsev VA, Preul MC, Chen L. Blood-Brain Barrier, Blood-Brain Tumor Barrier, and Fluorescence-Guided Neurosurgical Oncology: Delivering Optical Labels to Brain Tumors. Front Oncol 2020; 10:739. [PMID: 32582530 PMCID: PMC7290051 DOI: 10.3389/fonc.2020.00739] [Citation(s) in RCA: 103] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 04/17/2020] [Indexed: 12/17/2022] Open
Abstract
Recent advances in maximum safe glioma resection have included the introduction of a host of visualization techniques to complement intraoperative white-light imaging of tumors. However, barriers to the effective use of these techniques within the central nervous system remain. In the healthy brain, the blood-brain barrier ensures the stability of the sensitive internal environment of the brain by protecting the active functions of the central nervous system and preventing the invasion of microorganisms and toxins. Brain tumors, however, often cause degradation and dysfunction of this barrier, resulting in a heterogeneous increase in vascular permeability throughout the tumor mass and outside it. Thus, the characteristics of both the blood-brain and blood-brain tumor barriers hinder the vascular delivery of a variety of therapeutic substances to brain tumors. Recent developments in fluorescent visualization of brain tumors offer improvements in the extent of maximal safe resection, but many of these fluorescent agents must reach the tumor via the vasculature. As a result, these fluorescence-guided resection techniques are often limited by the extent of vascular permeability in tumor regions and by the failure to stain the full volume of tumor tissue. In this review, we describe the structure and function of both the blood-brain and blood-brain tumor barriers in the context of the current state of fluorescence-guided imaging of brain tumors. We discuss features of currently used techniques for fluorescence-guided brain tumor resection, with an emphasis on their interactions with the blood-brain and blood-tumor barriers. Finally, we discuss a selection of novel preclinical techniques that have the potential to enhance the delivery of therapeutics to brain tumors in spite of the barrier properties of the brain.
Collapse
Affiliation(s)
- Evgenii Belykh
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, United States
| | - Kurt V. Shaffer
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, United States
| | - Chaoqun Lin
- Department of Neurosurgery, School of Medicine, Southeast University, Nanjing, China
| | - Vadim A. Byvaltsev
- Department of Neurosurgery, Irkutsk State Medical University, Irkutsk, Russia
| | - Mark C. Preul
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, United States
| | - Lukui Chen
- Department of Neurosurgery, Neuroscience Center, Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| |
Collapse
|
9
|
Wadiura LI, Mischkulnig M, Hosmann A, Borkovec M, Kiesel B, Rötzer T, Mercea PA, Furtner J, Hervey-Jumper S, Rössler K, Berger MS, Widhalm G. Influence of Corticosteroids and Antiepileptic Drugs on Visible 5-Aminolevulinic Acid Fluorescence in a Series of Initially Suspected Low-Grade Gliomas Including World Health Organization Grade II, III, and IV Gliomas. World Neurosurg 2020; 137:e437-e446. [DOI: 10.1016/j.wneu.2020.01.243] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 12/21/2022]
|
10
|
Pippin AB, Voll RJ, Li Y, Wu H, Mao H, Goodman MM. Radiochemical Synthesis and Evaluation of 13N-Labeled 5-Aminolevulinic Acid for PET Imaging of Gliomas. ACS Med Chem Lett 2017; 8:1236-1240. [PMID: 29259740 DOI: 10.1021/acsmedchemlett.7b00311] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 11/15/2017] [Indexed: 01/05/2023] Open
Abstract
The endogenous amino acid, 5-aminolevulinic acid (5-ALA), has received significant attention as an imaging agent, including ongoing clinical trials for image-guided tumor resection due to its selective uptake and subsequent accumulation of the fluorescent protoporphyrin IX in tumor cells. Based on the widely reported selectivity of 5-ALA, a new positron emission tomography imaging probe was developed by reacting methyl 5-bromolevulinate with [13N] ammonia. The radiotracer, [13N] 5-ALA, was produced in high radiochemical yield (65%) in 10 min and could be purified using only solid phase cartridges. In vivo testing in rats bearing intracranial 9L glioblastoma showed peak tumor uptake occurred within 10 min of radiotracer administration. Immunohistochemical staining and fluorescent imaging was used to confirm the tumor location and accumulation of the tracer seen from the PET images. The quick synthesis and rapid tumor specific uptake of [13N] 5-ALA makes it a potential novel clinical applicable radiotracer for detecting and monitoring tumors noninvasively.
Collapse
Affiliation(s)
- Adam B. Pippin
- Department of Radiology
and
Imaging Sciences, Emory University Center for Systems Imaging, Wesley Woods Health Center, 1841 Clifton Road, NE, Atlanta, Georgia 30329, United States
| | - Ronald J. Voll
- Department of Radiology
and
Imaging Sciences, Emory University Center for Systems Imaging, Wesley Woods Health Center, 1841 Clifton Road, NE, Atlanta, Georgia 30329, United States
| | - Yuancheng Li
- Department of Radiology
and
Imaging Sciences, Emory University Center for Systems Imaging, Wesley Woods Health Center, 1841 Clifton Road, NE, Atlanta, Georgia 30329, United States
| | - Hui Wu
- Department of Radiology
and
Imaging Sciences, Emory University Center for Systems Imaging, Wesley Woods Health Center, 1841 Clifton Road, NE, Atlanta, Georgia 30329, United States
| | - Hui Mao
- Department of Radiology
and
Imaging Sciences, Emory University Center for Systems Imaging, Wesley Woods Health Center, 1841 Clifton Road, NE, Atlanta, Georgia 30329, United States
| | - Mark M. Goodman
- Department of Radiology
and
Imaging Sciences, Emory University Center for Systems Imaging, Wesley Woods Health Center, 1841 Clifton Road, NE, Atlanta, Georgia 30329, United States
| |
Collapse
|
11
|
Epithelial growth factor receptor expression influences 5-ALA induced glioblastoma fluorescence. J Neurooncol 2017; 133:497-507. [PMID: 28500562 PMCID: PMC5537329 DOI: 10.1007/s11060-017-2474-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 05/04/2017] [Indexed: 11/05/2022]
Abstract
The extent of 5-aminolevulinic acid (5-ALA) guided tumor resection has a determining impact in high-grade glioma and glioblastoma surgery. Yet the intensity of the 5-ALA induced fluorescence may vary within the tumor. We aimed to correlate 5-ALA induced fluorescence with the expression of epithelial growth factor receptor (EGFR) and its constitutively active version EGFRvIII in different glioblastoma (GBM) cell lines. To elucidate the role of EGFR in the metabolism of 5-ALA in GBM cell lines with variable EGFR expression status, we analyzed the activation of EGFR by its primary ligand EGF, and its downstream effect on Heme oxygenase-1 (HO-1), a key enzyme regulating the metabolism of Protoporphyrin IX (PpIX), the fluorescent metabolite of 5-ALA. Effects of direct pharmacological inhibition by Tin(IV)-Protoporphyrin (SnPP) or gene knockdown by small interfering RNA (siRNA) on HO-1 enzyme were analyzed in respect to 5-ALA induced fluorescence. Furthermore, inhibition of EGFR by Gefitinib was tested. A significant difference in 5-ALA induced fluorescence was obtained in U87MG (low EGFR expression) and LN229EGFR cells (EGFR overexpression) compared to BS153 (EGFR overexpression/EGFRvIII+). Treatment of U87MG and LN229EGFR cells with EGF significantly reduced cellular fluorescence, by promoting HO-1 transcription and expression in a concentration-dependent manner. This effect could be reversed by EGFR-specific siRNA treatment, which reduced protein expression of about 80% in U87MG. Remarkably, inhibition of HO-1 activity by SnPP or reduction of HO-1 protein levels by siHO-1 treatment restored fluorescence in all cell lines, independently of EGFR quantitative and qualitative expression. Gefitinib treatment was able to restore fluorescence after EGF stimulation in U87MG cells but not in BS153 cells, overexpressing EGFR/EGFRvIII. In GBM cell lines, 5-ALA induced fluorescence is variable and influenced by EGF-induced downstream activation of HO-1. HO-1 protein expression was identified as a negative regulator of 5-ALA induced fluorescence in GBM cells. We further propose that co-expression of EGFRvIII but not quantitative EGFR expression influence HO-1 activity and therefore cellular fluorescence.
Collapse
|
12
|
Richter JCO, Haj-Hosseini N, Hallbeck M, Wårdell K. Combination of hand-held probe and microscopy for fluorescence guided surgery in the brain tumor marginal zone. Photodiagnosis Photodyn Ther 2017; 18:185-192. [PMID: 28223144 DOI: 10.1016/j.pdpdt.2017.01.188] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 12/23/2016] [Accepted: 01/03/2017] [Indexed: 11/26/2022]
Abstract
BACKGROUND Visualization of the tumor is crucial for differentiating malignant tissue from healthy brain during surgery, especially in the tumor marginal zone. The aim of the study was to introduce a fluorescence spectroscopy-based hand-held probe (HHF-probe) for tumor identification in combination with the fluorescence guided resection surgical microscope (FGR-microscope), and evaluate them in terms of diagnostic performance and practical aspects of fluorescence detection. MATERIAL AND METHODS Eighteen operations were performed on 16 patients with suspected high-grade glioma. The HHF-probe and the FGR-microscope were used for detection of protoporphyrin (PpIX) fluorescence induced by 5-aminolevulinic acid (5-ALA) and evaluated against histopathological analysis and visual grading done through the FGR-microscope by the surgeon. A ratio of PpIX fluorescence intensity to the autofluorescence intensity (fluorescence ratio) was used to quantify the spectra detected by the probe. RESULTS Fluorescence ratio medians (range 0 - 40) measured by the probe were related to the intensity of the fluorescence in the FGR-microscope, categorized as "none" (0.3, n=131), "weak" (1.6, n=34) and "strong" (5.4, n=28). Of 131 "none" points in the FGR-microscope, 88 (67%) exhibited fluorescence with the HHF-probe. For the tumor marginal zone, the area under the receiver operator characteristics (ROC) curve was 0.49 for the FGR-microscope and 0.65 for the HHF-probe. CONCLUSIONS The probe was integrated in the established routine of tumor resection using the FGR-microscope. The HHF-probe was superior to the FGR-microscope in sensitivity; it detected tumor remnants after debulking under the FGR-microscope. The combination of the HHF-probe and the FGR-microscope was beneficial especially in the tumor marginal zone.
Collapse
Affiliation(s)
- Johan C O Richter
- Department of Biomedical Engineering, Linköping University, Sweden; Department of Neurosurgery Linköping University Hospital, Region Östergötland, Linköping, Sweden.
| | | | - Martin Hallbeck
- Department of Clinical Pathology and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Karin Wårdell
- Department of Biomedical Engineering, Linköping University, Sweden
| |
Collapse
|
13
|
Abstract
Oligopeptide transporters serve important functions in nutrition and pharmacology. In particular, these transporters help maintain the homeostasis of peptides. The peptide-transporter PEPT2 is a high-affinity and low-capacity type oligopeptide transporter from the proton-coupled oligopeptide transporter family. PEPT2 has recently received attention because of its potential application in targeted drug delivery. PEPT2 is widely distributed in kidney, central nervous system, and lung of organisms. In general, all dipeptides, tripeptides, and peptide-like drugs such as β-lactam antibiotics and angiotensin-converting enzyme inhibitors could be mediated and transported as a substrate of PEPT2. The design of many extant drugs and prodrugs is based on the substrate structure of PEPT2 to accelerate absorption via peptide transporters. Thus, this paper summarizes the substrate features of PEPT2 to promote the rational design of drugs and prodrugs that target peptide transporters.
Collapse
Affiliation(s)
- Dongxin Zhao
- School of Chemistry and Chemical Engineering, Henan University of Technology
| | | |
Collapse
|
14
|
Guyotat J, Pallud J, Armoiry X, Pavlov V, Metellus P. 5-Aminolevulinic Acid-Protoporphyrin IX Fluorescence-Guided Surgery of High-Grade Gliomas: A Systematic Review. Adv Tech Stand Neurosurg 2016:61-90. [PMID: 26508406 DOI: 10.1007/978-3-319-21359-0_3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The current first-line treatment of malignant gliomas consists in surgical resection (if possible) as large as possible. The existing tools don't permit to identify the limits of tumor infiltration, which goes beyond the zone of contrast enhancement on MRI. The fluorescence-guided malignant gliomas surgery was started 15 years ago and had become a standard of care in many countries. The technique is based on fluorescent molecule revelation using the filters, positioned within the surgical microscope. The fluorophore, protoporphyrin IX (PpIX), is converted in tumoral cells from 5-aminolevulinic acid (5-ALA), given orally before surgery. Many studies have shown that the ratio of gross total resections was higher if the fluorescence technique was used. The fluorescence signal intensity is correlated to the cell density and the PpIX concentration. The current method has a very high specificity but still lower sensibility, particularly regarding the zones with poor tumoral infiltration. This book reviews the principles of the technique and the results (extent of resection and survival).
Collapse
Affiliation(s)
- Jacques Guyotat
- Department of Neurosurgery, Neurological Hospital, Lyon, France.
| | - Johan Pallud
- Department of Neurosurgery, Sainte Anne Hospital, Paris, France.
- Paris Descartes University, Paris, France.
| | - Xavier Armoiry
- Délégation à la recherche clinique et à l'innovation, cellule innovation Hospices Civils de, Lyon, France.
| | - Vladislav Pavlov
- Department of Neurosurgery, Neurological Hospital, Lyon, France.
| | - Philippe Metellus
- Department of Neurosurgery, Timone Hospital, Marseille, France.
- University Aix Marseille, Marseille, France.
| |
Collapse
|
15
|
No 5-ALA fluorescence seen in a recurrent papillary tumour of the pineal region (PTPR). Acta Neurochir (Wien) 2015; 157:215-6. [PMID: 25520052 DOI: 10.1007/s00701-014-2308-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 12/03/2014] [Indexed: 10/24/2022]
|
16
|
Changes in rat urinary porphyrin profiles predict the magnitude of the neurotoxic effects induced by a mixture of lead, arsenic and manganese. Neurotoxicology 2014; 45:168-77. [DOI: 10.1016/j.neuro.2014.10.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 10/21/2014] [Accepted: 10/21/2014] [Indexed: 12/19/2022]
|
17
|
Richter JCO, Haj-Hosseini N, Andersson-Engel S, Wårdell K. Fluorescence spectroscopy measurements in ultrasonic navigated resection of malignant brain tumors. Lasers Surg Med 2011; 43:8-14. [PMID: 21254137 DOI: 10.1002/lsm.21022] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND AND OBJECTIVE Glioblastoma multiforme is a highly malignant primary brain tumor. It has no border but at best a marginal zone, however, invisible to the surgeon. An optical touch pointer (OTP) enabling differentiation of healthy and tumor tissue by means of fiber-optic fluorescence spectroscopy has been developed. In combination with an ultrasonic navigation system, the OTP may be used for demarcation of resectable tumor tissue. The aim of the study was to evaluate the clinical performance of OTP during surgery of malignant brain tumors. STUDY DESIGN/MATERIALS AND METHODS Nine patients were operated on with the standard surgical procedure, including white light microscopy and navigation. A total of 5 mg/kg bodyweight of 5-amino-levulin acid was orally administrated before surgery. The OTP was calibrated into the ultrasound-based navigation system and measurements were performed in tumor core and along the tumor border. The ratio between the protoporphyrin IX fluorescence at 635 nm and the autofluorescence was used for quantifications of data. Biopsies (n = 20), ultrasound images (n = 30), and visual inspection (n = 180) were compared to the fluorescence ratio. RESULTS/CONCLUSION Healthy and tumor tissue could be identified and differentiated with the OTP (P < 0.001). The fluorescence ratio in average was 0 outside the tumor and low in the gliotic edema zone around the tumor. It increased in the marginal zone and was highest in the solid tumor tissue. In the necrotic tissue, in the center of the tumor, the ratio in average was 0. The OTP can be used in combination with ultrasound-based navigation and may help to determine whether to resect otherwise not identifiable tissue.
Collapse
Affiliation(s)
- Johan C O Richter
- Department of Biomedical Engineering, Linköping University, Linköping 58185, Sweden.
| | | | | | | |
Collapse
|
18
|
Haj-Hosseini N, Richter J, Andersson-Engels S, Wårdell K. Optical touch pointer for fluorescence guided glioblastoma resection using 5-aminolevulinic acid. Lasers Surg Med 2010; 42:9-14. [PMID: 20077492 DOI: 10.1002/lsm.20868] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND AND OBJECTIVE Total tumor resection in patients with glioblastoma multiforme (GBM) is difficult to achieve due to the tumor's infiltrative way of growing and morphological similarity to the surrounding functioning brain tissue. The diagnosis is usually subjectively performed using a surgical microscope. The objective of this study was to develop and evaluate a hand-held optical touch pointer using a fluorescence spectroscopy system to quantitatively distinguish healthy from malignant brain tissue intraoperatively. STUDY DESIGN/MATERIALS AND METHODS A fluorescence spectroscopy system with pulsed modulation was designed considering optimum energy delivery to the tissue, minimal photobleaching of PpIX and omission of the ambient light background in the operating room (OR). 5-Aminolevulinic acid (5-ALA) of 5 mg/kg body weight was given to the patients with a presumed GBM prior to surgery. During the surgery a laser pulse at 405 nm was delivered to the tissue. PpIX in glioblastoma tumor cells assigned with peaks at 635 and 704 nm was detected using a fiber optical probe. RESULTS/CONCLUSION By using the pulsed fluorescence spectroscopy, PpIX fluorescence is quantitatively detected in the GBM. An effective suppression of low power lamp background from the recorded spectra in addition to a significant reduction of high power surgical lights is achieved.
Collapse
Affiliation(s)
- Neda Haj-Hosseini
- Department of Biomedical Engineering, Linköping University, Linköping 58185, Sweden.
| | | | | | | |
Collapse
|
19
|
Potapov AA, Usachev DJ, Loshakov VA, Cherekaev VA, Kornienko VN, Pronin IN, Kobiakov GL, Kalinin PL, Gavrilov AG, Stummer W, Golbin DA, Zelenkov PV. First experience in 5-ALA fluorescence-guided and endoscopically assisted microsurgery of brain tumors. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.mla.2008.07.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|