Series Of White Light Research Articles

Finite Element Modeling for Fluorescence Molecular Tomography

Non-contact Fluorescence Molecular Tomography (FMT) and Bioluminescence Tomography (BLT) has attracted more and more attention due to its unique advantages. For real experiments, how to obtain the 3D model of an object and the surface fluorescence distribution is one of the main obstacles. In this paper, an effective method to obtain the Finite Element Model is presented. We discuss the geometric and mathematical principles in detail. We prove that the FEM model generated by the method has enough quality for reconstruction. We demonstrate the quality of the model through a series of examples. This method can realize the whole process only by using a single-mode optical system. Firstly, a series of white light and fluorescence images are collected along the object in white light flat field illumination mode and excitation fluorescence mode respectively. The white light illumination images are used to reconstruct the 3D model contour of the object. After voxelization with appropriate resolution, we use the Delaunay algorithm to divide the model into tetrahedral finite elements. For the fluorescence image, we proposed a method based on vertex normal vector to realize the photon flux density mapping from 2D fluorescence image to 3D Finite Element Method (FEM) mesh nodes of the surface. The experimental results prove the accuracy of the model and the mapping, and the FEM obtained can meet the needs of FMT/ BLT reconstruction.

Finite Element Modeling for Fluorescence Molecular Tomography

Non-contact Fluorescence Molecular Tomography (FMT) and Bioluminescence Tomography (BLT) has attracted more and more attention due to its unique advantages. For real experiments, how to obtain the 3D model of an object and the surface fluorescence distribution is one of the main obstacles. In this paper, an effective method to obtain the Finite Element Model is presented. We discuss the geometric and mathematical principles in detail. We prove that the FEM model generated by the method has enough quality for reconstruction. We demonstrate the quality of the model through a series of examples. This method can realize the whole process only by using a single-mode optical system. Firstly, a series of white light and fluorescence images are collected along the object in white light flat field illumination mode and excitation fluorescence mode respectively. The white light illumination images are used to reconstruct the 3D model contour of the object. After voxelization with appropriate resolution, we use the Delaunay algorithm to divide the model into tetrahedral finite elements. For the fluorescence image, we proposed a method based on vertex normal vector to realize the photon flux density mapping from 2D fluorescence image to 3D Finite Element Method (FEM) mesh nodes of the surface. The experimental results prove the accuracy of the model and the mapping, and the FEM obtained can meet the needs of FMT/ BLT reconstruction.

HAL Blue-light Cystoscopy in High-risk Nonmuscle-invasive Bladder Cancer—Re-TURBT Recurrence Rates in a Prospective, Randomized Study

To evaluate the impact of hexaminolevulinate blue-light cystoscopy and transurethral resection of bladder tumors (TURBT) upon the short-term recurrence rate in high-risk nonmuscle-invasive bladder cancer (NMIBC) compared with conventional cystoscopy and resection. Between December 2007 and November 2009, 446 patients were randomized for blue-light cystoscopy/resection and for standard cystoscopy/resection, respectively. The inclusion criteria consisted of positive urinary cytology and ultrasonographic suspicion of bladder tumors. High-risk NMIBC patients (carcinoma in situ [CIS], pTaG3, and pT1) from both series underwent standard Re-TURBT 6 weeks after the initial procedure. The proportions of CIS, pTaG3, and pT1 cases in the initial series were 13.1%, 5.7%, and 22.2% in the blue light series and 11.3%, 5.7%, and 23.3% in the white light series. In total, 72 and 64 high-risk cases, respectively, were diagnosed in the blue- and white-light series. The overall short-term recurrence rate at Re-TURBT was 11.1% for the blue-light group and 31.2% for the white-light group. The recurrence rates were 4.3% versus 27.8% for CIS, 10% versus 22.2% for pTaG3, and 15.4% versus 35.1% for pT1 cases, in favor of the blue-light arm. The recurrence rate in patients presenting with high-grade tumors was 17.2% in the blue-light group and 37% in the white-light group. Blue-light cystoscopy and resection significantly reduced the short-term recurrence rates determined during the standard Re-TURBT in all categories of high-risk patients compared with the standard cystoscopy and resection.

Dual Doppler artery ligation and hemorrhoid treatment system

A dual Doppler artery ligation and haemorrhoid treatment system has a probe (16). The probe (16) has a disposable cylinder (18) with a cone-shaped cap (20) at the distal end and a support (22) adjacent to the proximal end. A series of white light emitting diodes (24) is mounted within the support. The support has a backing plate (26) proximally and an opening (34) to the cylinder and cone distally. The cylinder has an opening (28) adjacent to its distal end and a pair of ultrasonic transducers (36) secured on the cylinder laterally spaced on the center line proximal side of the opening. An echo analyzer (42) is operatively coupled to the probe and is adapted to emit signals and to detect and analyze received signals as a function of the blood flow there adjacent to produce an output which varies as a function of the arterial blood flow of a haemorrhoid extending through the aperture.