Early detection and evaluation of
brain tumors during surgery is crucial for accurate resection. Currently cryosections during surgery are regularly performed. Confocal
laser endomicroscopy (CLE) is a novel technique permitting in vivo histologic imaging with miniaturized endoscopic probes at excellent resolution. Aim of the current study was to evaluate CLE for in vivo diagnosis in different types and models of intracranial
neoplasia. In vivo histomorphology of healthy brains and two different C6
glioma cell line allografts was evaluated in rats. One cell line expressed EYFP, the other cell line was used for staining with
fluorescent dyes (
fluorescein,
acriflavine,
FITC-dextran and
Indocyanine green). To evaluate future application in patients, fresh surgical resection specimen of human intracranial
tumors (n = 15) were examined (
glioblastoma multiforme,
meningioma,
craniopharyngioma,
acoustic neurinoma, brain
metastasis,
medulloblastoma, epidermoid
tumor). Healthy brain tissue adjacent to the samples served as control. CLE yielded high-quality histomorphology of normal brain tissue and
tumors. Different
fluorescent agents revealed distinct aspects of tissue and cell structure (nuclear pattern, axonal pathways,
hemorrhages). CLE discrimination of neoplastic from healthy brain tissue was easy to perform based on tissue and cellular architecture and resemblance with histopathology was excellent. Confocal
laser endomicroscopy allows immediate in vivo imaging of normal and neoplastic brain tissue at high resolution. The technology might be transferred to scientific and clinical application in neurosurgery and neuropathology. It may become helpful to screen for
tumor free margins and to improve the surgical resection of malignant
brain tumors, and opens the door to in vivo molecular imaging of
tumors and other
neurologic disorders.