Surgical and Audiologic Comparison Between Sophono and Bone-Anchored Hearing Aids Implantation

OBJECTIVES: Bone-anchored hearing aids (BAHA) occasionally cause soft tissue problems due to abutment. Because Sophono does not have abutment penetrating skin, it is thought that Sophono has no soft tissue problem relating to abutment. On the other hand, transcutaneous device's output is reported to be 10 to 15 dB lower than percutaneous device. Therefore, in this study, Sophono and BAHA were compared to each other from surgical and audiological points of view. METHODS: We retrospectively reviewed the medical records of 9 Sophono patients and 10 BAHA patients. In BAHA cases, single vertical incision without skin thinning technique was done. We compared Sophono to BAHA by operation time, wound healing time, postoperative complications, postoperative hearing gain after switch on, and postoperative air-bone gap. RESULTS: The mean operation time was 60 minutes for Sophono and 25 minutes for BAHA. The wound healing time was 14 days for Sophono and 28 days for BAHA. No major intraoperative complication was observed. Skin problem was not observed in the 2 devices for the follow-up period. Postoperative hearing gain of bilateral aural atresia patients was 39.4 dB for BAHA (n=4) and 25.5 dB for Sophono (n=5). However, the difference was not statistically significant. In all patients included in this study, the difference of air-bone gap between two groups was 16.6 dB at 0.5 kHz and 18.2 dB at 4 kHz. BAHA was statistically significantly better than Sophono. CONCLUSION: Considering the audiologic outcome, BAHA users were thought to have more audiologic benefit than Sophono users. However, Sophono had advantages over BAHA with abutment in cosmetic outcome. Sophono needed no daily skin maintenance and soft tissue complication due to abutment would not happen in Sophono. Therefore, a full explanation about each device is necessary before deciding implantation.

Comparison of the gallbladder damage caused by microwave ablation and cryoablation in vivo porcine livers.

PURPOSE: To compare the imaging, anatomy, and histopathology of the porcine liver tissue adjacent to the gallbladder, as well as the temperature of the gallbladder wall and the damage degree of gallbladder wall at different times after microwave ablation (MWA) and cryoblation. MATERIALS AND METHODS: Sixteen pigs were randomly divided into MWA group (Group M) and cryoblation group (Group C). The pigs were randomly divided into 8 subgroups according to their execution time, with 2 pigs in every subgroup. The pigs were executed immediately after operation, or at 1‑, 2‑, and 4‑weeks postoperatively according to their assigned subgroup. The imaging and anatomy change of the liver ablation zone and the gallbladder wall were recorded. Histopathological observation was carried out for the damage portion of the gallbladder and the adjacent liver parenchyma. RESULTS: (1) There were no significant statistical differences of the damage degree of the gallbladder between the two groups (P = 0.842). (2) Gallbladder wall edema occurred in Group M immediately after ablation (6/8), of which, 3 cases of gallbladder wall reached full‑thickness damage; overlapping of ice ball and gallbladder wall occurred in Group C (5/8), of which, 4 cases of gallbladder wall reached full‑thickness damage. However, there was neither perforation of gallbladder, biliary fistula, nor liver abscess in all cases. CONCLUSION: Both MWA and cryoablation for liver tissues adjacent to the gallbladder could lead to different damage degrees of the gallbladder wall, but not gallbladder perforation even under the condition of full‑thickness damage.

Single Vertical Incision Technique without Skin Thinning for the Bone Anchored Hearing Aid Surgery / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: After the bone anchored hearing aid (BAHA) surgery, soft tissue problems have frequently been reported. To solve this problem, a surgical procedure that routinely involves so-called skin thinning using BAHA dermatome has been utilized. But, this procedure includes many peri-implant complications and cosmetic trouble. Recently, a single vertical incision technique that does not involve skin thinning has been reported with favorable results. In this study, we evaluated the benefits of performing this procedure without skin thinning compared with the dermatome technique. SUBJECTS AND METHOD: We evaluated 10 patients who were operated on without skin thinning using longer (8.5 mm) abutments (the test group) and 5 patients with the routine skin thinning and 5.5-mm abutments (the control group). A mean follow-up time was 11.3 months, the mean age was 34.2 years in the test group, the mean follow-up time was 54.5 months and a mean age is 24.5 years in the control group. RESULTS: The mean time required for surgery was 25 minutes and 55 minutes for the test and control groups, respectively. The wound healing time was 28 days and 56 days for the test and control groups, respectively. Fixture extrusion, skin infection and skin overgrowth were not observed in the test group but fixture extrusion case, two skin infection cases and two skin overgrowth cases were observed in the control group. Two cases of abutment loosening were observed in the test group. CONCLUSION: The single vertical incision technique without skin thinning has many benefits when compared with the BAHA dermatome. With this technique, infection and skin overgrowth could be reduced, and a more rapid procedure and a more short healing time could also be possible. Moreover, the aesthetic outcome was far better when no skin thinning was involved.

Experimental Study of Laryngeal Chemoreflex in Puppies / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Mechanical or chemical stimulation of the supraglottic mucosa may result in either or both of two responses: the laryngeal adductor reflex response (LAR), which causes glottic closure, and the laryngeal chemoreflex (LCR), which results in centrally mediated apnea, hemodynamic instability and swallowing. Exaggeration of this normally protective reflexes is thought to be responsible for several disorders, including the sudden infant death syndrome (SIDS). MATERIALS AND METHODS: The supraglottic laryngeal mucosa which was topically stimulated by saline, distilled water, cow's milk and acid at pH 1.0 was introduced in 14 anesthetized puppies of three different age groups. In group I, four puppies were 2-weeks-of-age, and in group II and III, five puppies were 4 and 6-weeks-of-age, respectively. RESULT: 1) Strong acid (pH 1.0) induced the LCR response.20) After stimulating, respiration was depressed initially, followed by later hyperventilation. We found strong contraction or laryngospasm of thyroarytenoid (TA) muscle after a short period of latency. 3) Respiration was not, or minimally depressed in group I. Moderate depression or apnea was elicited in group II and III. 4) After stimulating, the heart rate was reduced, but it had no statistical meaning. 5) We found 3 types of TA muscle contraction pattern. Type I showed no laryngospasm, but large contraction wave was noted by EMG. Type II showed no laryngospasm, but strong contraction was noted initially and followed by some large waves by EMG. Type III showed laryngospasm that was visible to the naked eye and by EMG. 6) Peak to peak amplitude differences of TA muscle were significantly increased statistically in all age groups. CONCLUSION: We suggest that the LCR is an age-dependent response which is absent in very young puppies before 2 weeks and appears after that age. Thus, it has important implications that postnatal neural maturation may influence laryngeal reflex to some extent.

Lectin-binding patterns of canine olfactory mucosa / 대한이비인후과학회지

No abstract available.