Objectives Narrow band imaging cystoscopy can increase the visualization and detection of Hunner's lesions. A single‐center, prospective clinical trial was carried out aiming to show the effectiveness of narrow band imaging‐assisted transurethral electrocoagulation for ulcer‐type interstitial cystitis/painful bladder syndrome. Methods A total of 23 patients (19 women and 4 men) diagnosed as having ulcer‐type interstitial cystitis/painful bladder syndrome were included. All typical Hunner's lesions and suspected areas identified by narrow band imaging were electrocoagulated endoscopically after the biopsy of those lesions. Therapeutic efficacy was assessed prospectively by using visual analog scale score of pain, O'Leary–Sant's symptom index, O'Leary–Sant's problem index and overactive bladder symptom score. Results The mean follow‐up period was 22 months. All patients (100%) experienced a substantial improvement in pain. The average visual analog scale pain scores significantly decreased from 7.3 preoperatively to 1.2 1 month postoperatively. A total of 21 patients (91.3%) who reported improvement had at least a 50% reduction in bladder pain, and five reported complete resolution. Daytime frequency was significantly decreased postoperatively. O'Leary–Sant's symptom index, O'Leary–Sant's problem index and overactive bladder symptom score were significantly decreased postoperatively. However, during the follow‐up period, a total of six patients had recurrence, and repeat narrow band imaging‐assisted transurethral electrocoagulation of the recurrent lesions was carried out for five of the six patients, with good response in relieving bladder pain. Conclusions Our results showed that narrow band imaging‐assisted transurethral electrocoagulation could be a valuable therapeutic alternative in patients with ulcer‐type interstitial cystitis/painful bladder syndrome, with good efficacy and reduction of recurrence rate.

In this paper, we consider the collaborative editing of twodimensional (2D) data such as handwritten letters and illustrations. In contrast to the editing of 1D data, which is generally realized by the combination of insertion/deletion of characters, overriding of strokes can have a specific meaning in editing 2D data. In other words, the appearance of the resulting picture depends on the reflection order of strokes to the shared canvas in addition of the absolute coordinate of the strokes. We propose a Peer-to-Peer (P2P) collaborative drawing system consisting of several nodes with replica canvas, in which the consistency among replica canvases is maintained through data channel of WebRTC. The system supports three editing modes concerned with the reflection order of strokes generated by different users. The result of experiments indicates that the proposed system realizes a short latency of around 120 ms, which is a half of a cloud-based system implemented with Firebase Realtime Database. In addition, it realizes a smooth drawing of pictures on remote canvases with a refresh rate of 12 fps.

We proposed and demonstrated a practical method for simultaneous measurement of the refractive index and the thickness of a transparent plate, based on the low coherence interferometry. This paper suggests that our method is applicable for birefringence measurement using unpolarized light source. Small birefringence of thin medium such as LiTaO3 crystal is measured with high accuracy, by introducing dispersion compensation into the low coherence interferometry.