Influence of a Paclitaxel-eluting Expandable Metallic Stent on Tissue Hyperplasia: An Experimental Study in a Canine Tracheal Model

PURPOSE: To evaluate the efficacy of a paclitaxel-eluting expandable metallic stent in reducing tissue hyperplasia following stent placement in a canine tracheal model. MATERIALS AND METHODS: Nine paclitaxel-eluting stents (drug stent, DS) consisting of a proximal bare part and a distal polyurethane-covered part were placed in the trachea of nine dogs and nine control stents (control stent, CS) were placed in the other nine dogs. The dogs were scheduled to be sacrificed 12 weeks after stent placement. Gross and histological factors, such as epithelial erosion/ulcer, granulation tissue thickness and inflammatory cell infiltration were evaluated after each dog was sacrificed. RESULTS: There were no procedure-related complications or malpositioning of any of the stents. One CS migrated less than eight weeks following stent placement. Four dogs (one DS and three CS dogs) died between three and five weeks following stent placement. Therefore, pathologic specimens were obtained from eight DS and five CS dogs. Epithelial erosion/ulcer or inflammatory cell infiltration was slightly more prominent in the DS cases than in the CS cases, in both the bare part and the covered part. However, the data was not statistically significant. Granulation tissue thickness was lower in the DS cases than in the CS cases in both the bare part (mean, 3.63-mm vs. 4.37-mm) and the covered part (mean, 1.75-mm vs. 2.78 mm), but the data was also statistically insignificant. CONCLUSION: Although the data was not statistically significant, placement of paclitaxel-eluting expandable metallic stent demonstrates a tendency toward a decrease in granulation tissue thickness in canine tracheal models.

Balloon Sheaths for Gastrointestinal Guidance and Access: A Preliminary Phantom Study

OBJECTIVE: We wanted to evaluate the feasibility and usefulness of a newly designed balloon sheath for gastrointestinal guidance and access by conducting a phantom study. MATERIALS AND METHODS: The newly designed balloon sheath consisted of an introducer sheath and a supporting balloon. A coil catheter was advanced over a guide wire into two gastroduodenal phantoms (one was with stricture and one was without stricture) ; group I was without a balloon sheath, group ll was with a deflated balloon sheath, and groups III and IV were with an inflated balloon and with the balloon in the fundus and body, respectively. Each test was performed for 2 minutes and it was repeated 10 times in each group by two researchers, and the positions reached by the catheter tip were recorded. RESULTS: Both researchers had better performances with both phantoms in order of group IV, III, II and I. In group IV, both researchers advanced the catheter tip through the fourth duodenal segment in both the phantoms. In group I, however, the catheter tip never reached the third duodenal segment in both the phantoms by both the researchers. The numeric values for the four study groups were significantly different for both the phantoms (p < 0.001). A significant difference was also found between group III and IV for both phantoms (p < 0.001). CONCLUSION: The balloon sheath seems to be feasible for clinical use, and it has good clinical potential for gastrointestinal guidance and access, particularly when the inflated balloon is placed in the gastric body.

Placement of an Implantable Port Catheter in the Biliary Stent: An Experimental Study in Dogs

PURPOSE: To investigate the feasibility of port catheter placement following a biliary stent placement. MATERIALS AND METHODS: We employed 14 mongrel dogs as test subject. and after the puncture of their gall bladders using sonographic guidance, a 10-mm in diameter metallic stent was placed at the common duct. In 12 dogs, a 6.3 F port catheter was placed into the duodenum through the common duct and a port was secured at the subcutaneous space following stent placement. As a control group, an 8.5 F drain tube was placed into the gallbladder without port catheter placement in the remaining two dogs. Irrigation of the bile duct was performed every week by injection of saline into the port, and the port catheter was replaced three weeks later in two dogs. Information relating to the success of the procedure, complications and the five-week follow-up cholangiographic findings were obtained. RESULTS: Placement of a biliary stent and a port catheter was technically successful in 13 (93%) dogs, while stent migration (n=3), gallbladder rupture (n=1) and death (n=5) due to subcutaneous abscess and peritonitis also occurred. The follow-up was achieved in eight dogs (seven dogs with a port catheter placement and one dog with a drain tube placement). Irrigation of the bile duct and port catheter replacement were successfully achieved without any complications. Cholangiograms obtained five weeks after stent placement showed diffuse biliary dilation with granulation tissue formation. However, focal biliary stricture was seen in one dog with stent placement alone. CONCLUSION: Placement of a port catheter following biliary stent placement seems to be feasible. However, further investigation is necessary to reduce the current complications.

Reduction of Tissue Hyperplasia with a 188Re-MAG3-filled Balloon Dilation: Experimental Study with a Rabbit Esophageal Model

PURPOSE: The purpose of this study was to evaluate the feasibility and efficacy of beta-radiation therapy with a rhenium-188-mercaptoacetyltriglycine ((188)Re-MAG(3)) filled balloon to prevent tissue hyperplasia secondary to stent placement in a rabbit esophageal model. MATERIALS AND METHODS: Fifteen rabbits were divided into the three study groups. The ten rabbits having the radioactive balloon dilation performed immediately after stent placement were scheduled to be sacrificed at six weeks; the 20 Gy (Group I, n=5) or 40 Gy (Group II, n=5) at 1 mm away from the balloon surface were also sacrificed at six weeks. The remaining five rabbits that had conventional balloon dilation done immediately after stent placement were scheduled to be sacrificed six weeks later; this was the control group (Group III). At follow-up, we obtained esophagography and the histologic findings (epithelial layer thickness, degree of destruction of the muscularis propria, and degree of submucosal inflammatory cell infiltration) at both the normal area and the mid-stent area for each esophageal specimen after sacrificing each rabbit. The differences among the three groups were statistically assessed using Kruskal-Wallis and Mann-Whitney U tests. RESULTS:There were no complications such as migration after stent placement. Nine of the rabbits died 1-3 weeks after stent placement and the stents were partially obstructed with a lot of residue, so it was impossible to compare the esophagographic findings among the three groups. Esophageal perforation (n=6) and mucosal reddish changes (n=5) of the esophagus adjacent to the stent were observed only for rabbits of group I or II. The esophageal mucosa displayed smoothness in group I and II, and the esophageal mucosa displayed nodularity in group III. The degree of destruction of the muscularis propria was significantly higher in group I or II when compared to group III (p<0.05). CONCLUSION: Beta-irradiation using a (188)Re-MAG(3)-filled balloon dilation has the potential for preventing tissue hyperplasia secondary to stent placement in a rabbit esophageal model.

A Case of Mastoid Osteoma / 대한이비인후과학회지

Osteomas are benign neoplasms of bone which usually produce symptoms secondary to pressure on adjacent structures. In the head and neck region, osteomas most commonly arise in fronto-ethmoidal areas. In the temporal bone, the external auditory canal is the favored location, while mastoid is not. This paper reviewed a case of an osteoma of the mastoid with a cosmetic problem.

The Study on the Preventive Method of the Middle Ear Barotrauma Caused by Hyperbaric Oxygen Therapy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Middle ear barotrauma is a damage of the ear resulting from the pressure difference between the middle ear and the atmospheric environment. We investigated the effects of chewing gum and administering the systemic decongestant in hyperbaric oxygen therapy. MATERIALS AND METHOD: We investigated the cases of the middle ear barotrauma which came from hyperbaric oxygen therapy for finger replantation. We studied 81 patients without E-tube dysfunction. They were divided into three groups: the non-treated patients, the patients chewing gums and receiving high-pressure treatment, and the patients receiving the systemic decongestant. We investigated the patients for symptoms, otoscopic findings, tympanometry, and PTA. Otoscopic findings were classified by modified Teed classification. RESULTS: In the first group, 36 of 60 (60%) ears had otologic symptoms, 37 of 60 (62%) ears were above the grade 1, 31 of 60 (52%) ears were B or C type in tympanometry and 20 of 60 (33%) ears were above 20dB in AB gap (air-bone gap). In the second group, 23 of 60 (38%) ears had the otologic symptom, 26 of 60 (43%) ears were above the grade 1, 19 of 60 (32%) ears were the B or C type and 10 of 60 (17%) ears were above 20dB in AB gap. In the third group, 18 of 42 (43%) ears had the otologic symptoms, 19 of 42 (45%) ears were above the grade 1, 15 of 42 (36%) ears were the B or C type and 7 of 42 (17%) ears were above 20dB in the AB gap. CONCLUSION: The second group was better than the first group with regard to otologic symptom, otoscopic findings, tympanometry, PTA, and showed statistical significance. On the other hand, the third group was effective but did not show statistical significance.

A case of transsacral approach for traumatic urethrorectal fistula / 대한비뇨기과학회지

The causes of urethrorectal fistula are multiple such as trauma, open prostatectomy, radiation therapy, infection and congenital anomaly and so forth. In considering the injured area, length and the condition or periurethral tissue, numerous approaches have been advocated for the treatment of the traumatic urethrorectal fistula. Herein we report the experience of successful transsacral repair of traumatic urethrorectal fistula in a 14 year-old male patient 3 months after cystostomy and colostomy installed.

Transrectal prostatic needle biopsy using the bioty gun with needle-protecting sheath / 대한비뇨기과학회지

Biopty gun is an instrument designed for obtaining the prostatic tissue. But there is danger of injury or an examiner`s finger by the sharp needle and risk of unnecessary injury of the rectal mucosa during transrectal approach to the prostate. Therefore we designed the needle-protecting sheath over Biopty gun to eliminate these problems and conduct safe maneuver.