Probability-Based LIDAR-Camera Calibration Considering Target Positions and Parameter Evaluation Using a Data Fusion Map.

The data fusion of a 3-D light detection and ranging (LIDAR) point cloud and a camera image during the creation of a 3-D map is important because it enables more efficient object classification by autonomous mobile robots and facilitates the construction of a fine 3-D model. The principle behind data fusion is the accurate estimation of the LIDAR-camera's external parameters through extrinsic calibration. Although several studies have proposed the use of multiple calibration targets or poses for precise extrinsic calibration, no study has clearly defined the relationship between the target positions and the data fusion accuracy. Here, we strictly investigated the effects of the deployment of calibration targets on data fusion and proposed the key factors to consider in the deployment of the targets in extrinsic calibration. Thereafter, we applied a probability method to perform a global and robust sampling of the camera external parameters. Subsequently, we proposed an evaluation method for the parameters, which utilizes the color ratio of the 3-D colored point cloud map. The derived probability density confirmed the good performance of the deployment method in estimating the camera external parameters. Additionally, the evaluation quantitatively confirmed the effectiveness of our deployments of the calibration targets in achieving high-accuracy data fusion compared with the results obtained using the previous methods.

A two-tiered structure device based on stereolithography for residual mandible repositioning in mandibular reconstruction with fibular flap.

OBJECTIVE: We invented a two-tiered structure device based on stereolithography for residual mandible repositioning in mandibular reconstruction with fibular flap, and examined its usefulness. PATIENTS AND METHODS: A total of eight patients (six carcinomas and two osteomyelitis) who had undergone mandibular reconstruction with fibular flap were included. Mandibular defects according to Jewer's classification were L for five, LC for two, and H for one patient (range of bone defect size, 7.7-13.3 cm). Based on a stereolithographic mandibular model, a two-tiered structure device was made preoperatively with resin, and was applied during surgery to define the accurate position of residual mandible following segmental mandibulectomy. Postoperative aesthetic and functional outcomes, including dental status, diet, and speech were evaluated. RESULTS: The device was applied without any problems during surgery. Follow-up period ranged from eight to twenty-two months. Good postoperative alignment of the grafts and occlusion were also achieved in all eight patients. Five patients were able to return to eating meals as they had pre-surgery, and two patients required dental rehabilitation with dentures. As for speech, four patients scored ten points, three patients scored eight points, and one patient scored four points in Hirose's scoring system, which means that seven patients was rated as excellent, and one patient was rated as poor. Aesthetic outcomes were excellent in three patients, good in three patients, and fair in two patients. CONCLUSION: Our device was easy to prepare, successfully maintained the precise position of the residual mandible, and facilitated bone graft cutting and insetting during reconstruction. © 2016 Wiley Periodicals, Inc. Microsurgery 37:509-515, 2017.

[A case of toxicity caused by drug interaction between capecitabine and phenytoin in patient with colorectal cancer].

We present a case of toxicity caused by a drug interaction between capecitabine and phenytoin (PHT). The drug combination elevated the plasma level of PHT in a patient on chemotherapy with capecitabine for colorectal cancer. Our patient was a 44-year-old woman diagnosed with epilepsy in her 20's, being treated with valproic acid (VPA) and PHT. Adjuvant chemotherapy with capecitabine began following surgery for colorectal cancer. Seven weeks later, she developed numbness, dizziness, dysarthria and difficulty walking, and was hospitalized for investigation. Her serum PHT level was elevated at 35. 1 µg/ mL. This case suggests that when capecitabine and PHT are coadministered, PHT levels should be monitored frequently, and that PHT dosage should be adjusted accordingly if it cannot be replaced by an alternative anticonvulsant.

Reversal of large ischemic injury on hyper-acute diffusion MRI.

Reversal of early ischemic injury on diffusion-weighted MRI (DWI) occurs rarely. In a stroke patient who abruptly developed stupor and left hemiparesis, DWI scanned 78 min after onset demonstrated a large ischemic injury in the right hemisphere with a DWI-ASPECTS (Albert Stroke Program Early Computed Tomography Score) of 5 points, although baseline brain CT was perfectly normal. MR angiography (MRA) showed an occlusion of the right middle cerebral artery trunk, and the patient received intravenous thrombolysis 105 min after onset. A second MRA 30 h later showed complete vessel recanalization, and DWI demonstrated a perfect reversal of the initial large ischemic injury, associated with very small thrombus-fragmented cortical surface infarctions. Outcome at 3 months was a modified Rankin Scale score of 0, and the fluid-attenuated inversion recovery image showed only a small final infarction at the cortical surface. Hyper-acute DWI-defined large ischemic injury may very rarely represent a nearly perfect reversible area, and it may be a therapeutic target.