Red-light excitation of protoporphyrin IX fluorescence for subsurface tumor detection.
J Neurosurg
; 128(6): 1690-1697, 2018 06.
Article
em En
| MEDLINE
| ID: mdl-28777025
ABSTRACT
OBJECTIVE The objective of this study was to detect 5-aminolevulinic acid (ALA)-induced tumor fluorescence from glioma below the surface of the surgical field by using red-light illumination. METHODS To overcome the shallow tissue penetration of blue light, which maximally excites the ALA-induced fluorophore protoporphyrin IX (PpIX) but is also strongly absorbed by hemoglobin and oxyhemoglobin, a system was developed to illuminate the surgical field with red light (620-640 nm) matching a secondary, smaller absorption peak of PpIX and detecting the fluorescence emission through a 650-nm longpass filter. This wide-field spectroscopic imaging system was used in conjunction with conventional blue-light fluorescence for comparison in 29 patients undergoing craniotomy for resection of high-grade glioma, low-grade glioma, meningioma, or metastasis. RESULTS Although, as expected, red-light excitation is less sensitive to PpIX in exposed tumor, it did reveal tumor at a depth up to 5 mm below the resection bed in 22 of 24 patients who also exhibited PpIX fluorescence under blue-light excitation during the course of surgery. CONCLUSIONS Red-light excitation of tumor-associated PpIX fluorescence below the surface of the surgical field can be achieved intraoperatively and enables detection of subsurface tumor that is not visualized under conventional blue-light excitation. Clinical trial registration no. NCT02191488 (clinicaltrials.gov).
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Protoporfirinas
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Neoplasias Encefálicas
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Procedimentos Neurocirúrgicos
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Corantes Fluorescentes
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Glioma
Tipo de estudo:
Diagnostic_studies
Limite:
Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
J Neurosurg
Ano de publicação:
2018
Tipo de documento:
Article