Intra-operative brain tumor detection using elastic light single-scattering spectroscopy: a feasibility study

Abstract

We have investigated the potential application of elastic light single-scattering spectroscopy (ELSSS) as an adjunctive tool for intraoperative rapid detection of brain tumors and demarcation of the tumor from the surrounding normal tissue. Measurements were performed on 29 excised tumor specimens from 29 patients. There were 21 instances of low-grade tumors and eight instances of high-grade tumors. Normal gray matter and white matter brain tissue specimens of four epilepsy patients were used as a control group. One low-grade and one high-grade tumor were misclassified as normal brain tissue. Of the low- and high-grade tumors, 20 out of 21 and 7 out of 8 were correctly classified by the ELSSS system, respectively. One normal white matter tissue margin was detected in a high-grade tumor, and three normal tissue margins were detected in three low-grade tumors using spectroscopic data analysis and confirmed by histopathology. The spectral slopes were shown to be positive for normal white matter brain tissue and negative for normal gray matter and tumor tissues. Our results indicate that signs of spectral slopes may enable the discrimination of brain tumors from surrounding normal white matter brain tissue with a sensitivity of 93% and specificity of 100%.

Diagnosis of pelvic lymph node metastasis in prostate cancer using single optical fiber probe

“…2 [15,16]. Turbid media includes scatters with different sizes like tissue and Mie oscillations disappear due to overlapping of the different spectra originated from the scatters in this medium [5][6][7]15,16]. After these calibration measurements, we acquired spectrum from excised lymph nodes, R( ) s .…”

“…ROC curve, comparing reactive and metastatic pelvic lymph nodes. [2][3][4][5][6][7][8]15,16]. During spectral measurements, fiber optic probe was gently placed in contact with the cut surface of the node.…”

“…ELSSS system is used for detection of pelvic lymph node metastasis in men which sensitive to the epithelial morphology and nuclear size [2][3][4] scattering there is a negligible energy transfer and there is only spatial distribution of light changes in the tissue. ELSSS system has been used previously as a diagnostic technique [2][3][4][5][6][7][8] moreover; there has been a great deal of investigation in cancer detection by using other spectroscopic techniques [9][10][11][12][13]. Significant portion of light is scattered from the nucleus which is the major internal scatterer in the cell and the difference in the index of refraction between the cytoplasm and the cell membrane causes light scattering [12,13].…”

Retrieval of chromophore concentration in a tissue phantom by diffuse reflectance spectroscopy

“…There fore, these methods have received increasing attention in recent years. Some of the optical methods employed are fluorescence spectroscopy [5,6], optical coher ence tomography [7,8], Raman spectroscopy [9,10] and light scattering spectroscopy [11][12][13]. Optical methods aim to determine the relationship between biological and optical properties for diagnostic pur poses.…”

The Effect of Probe Pressure on In Vivo Single Fiber Reflectance Spectroscopy

“…The advantages of SFRS over other techniques such as spatially resolved diffuse reflectance spectroscopy (DRS) 2 are the simplicity of the setup and the small dimensions of the fiber-optic probes. 3 It has shown its potential in diagnosis of cancer and pre-cancer in lung lymph nodes, 4 brain, 5 skin 6 and uterine cervix. 7 In order to obtain clinically useful information about the measured tissue, the spectroscopy results must depend solely on the tissue characteristics rather than environmental parameters, such as probe pressure.…”