Bladder cancer is the fourth most common cancer in men and is considered to have the highest rate of recurrence of all cancers at ~70%, and transitional cell carcinoma (TCC) is the most common form of intrabladder malignancy. Current standard-of-care for Stages 2 or higher is radical cystectomy, which involves removal of the urinary bladder and nearby lymph nodes. Alternative, organ-sparing treatments such as chemo- or radiotherapy are relatively ineffective against these cancers. The latter is effective when precisely targeted, but suffers from accuracy issues due to low contrast from computed tomography guidance. These motivate an innovative approach to more precisely visualize and spatially pinpoint TCC. This manuscript presents a novel non-invasive computer vision pipeline that can extract 3D structural information from 2D images obtained during routine flexible cystoscopy. The pipeline utilized camera calibration, adaptive thresholding, Scale Invariant Feature Transform (SIFT), and a Structure from Motion (SFM) implementation to reconstruct 3D point clouds of the inner surface of organ phantoms and an <i>ex vivo</i> porcine bladder. 3D point clouds were processed by Poisson reconstruction to generate a textured, triangle meshed 3D surface. The reconstruction pipeline generated a visually recognizable, qualitative 3D representation of the bladder from 2D video captured via flexible cystoscopy. Once further developed, this approach will enhance the targeting precision of external beam radiotherapy, providing clinicians with better organ-sparing methods to treat TCC.
This paper describes a new infusion catheter, based on our fiberoptic microneedle device (FMD), designed with the objective of photothermally augmenting the volumetric dispersal of infused therapeutics. We hypothesize that concurrent delivery of laser energy, causing mild localized photothermal heating (4-5 °C), will increase the spatial dispersal of infused chemotherapy over a long infusion period. Agarose brain phantoms, which mimic the brain’s mechanical and fluid conduction properties, were constructed from 0.6 wt% Agarose in aqueous solution. FMDs were fabricated by adhering a multimode fiberoptic to a silica capillary tube, such that their flat-polished tips co-terminated. Continuous wave 1064 nm light was delivered simultaneously with FD&C Blue #2 (5%) dye into phantoms. Preliminary experiments, where co-delivery was tested against fluid delivery alone (through symmetrical infusions into <i>in vivo</i> rodent models), were also conducted. In the Agarose phantoms, volumetric dispersal was demonstrated to increase by more than 3-fold over a four-hour infusion time frame for co-delivery relative to infusion-only controls. Both forward and backward (reflux) infusions were also observed to increase slightly. Increased volumetric dispersal was demonstrated with co-delivery in an <i>in vivo</i> rodent model. Photothermal augmentation of infusion was demonstrated to influence the directionality and increase the volume of dye dispersal in Agarose brain phantoms. With further development, FMDs may enable a greater distribution of chemotherapeutic agents during CED therapy of brain tumors.