Current trends of practical issues concerning micropapillary thyroid carcinoma: The Korean Society of Thyroid-Head and Neck Surgery.

Although several thyroid associations have published various guidelines, controversies especially in cases of micropapillary thyroid cancer (MPTC) still exist. This survey was designed to collect information about diagnostic tests and treatments performed on patients with MPTC and help identify current trends in thyroid surgery.We developed questionnaires about the management methods for MPTC, which were used to identify factors related to indications of fine needle aspiration (FNA), type of surgery, and central lymph node dissection (CLND). Active 60 members of the Korean Society of Thyroid-Head and Neck Surgery participated in the study in September 2016.Ultrasound-guided FNA was usually initiated when the tumor was at least 5 mm (60%). All respondents preferred ultrasound-guided FNA and surgery for nodules with extrathyroidal extension (ETE). The preferred treatment option for intraglandular MPTC was lobectomy (92%) rather than active surveillance (8%). Posterolateral ETE increased the respondents' preference for total thyroidectomy (61.7%). Active surveillance was preferred for tumors <5 mm, which was decreased by the presence of ETE. The presence of ETE (73.3%) and its proximity to critical organs (46.7%) were the main determining factors for prophylactic CLND. For multiple metastatic lymph nodes at level III, selective neck dissection including levels IIb (23.3%) and V (78.3%) was preferred in addition to levels IIa, III, VI, and V.Korean head and neck surgeons favored total thyroidectomy and CLND in cases wherein ETE, central lymph node metastasis, or critical organ involvement was suspected.

The Effect of Polydeoxyribonucleotide on Ischemic Rat Skin Flap Survival.

Polydeoxyribonucleotide (PDRN) has multiple vascular actions such as angiogenesis and production of a vascular endothelial growth factor (VEGF) through the adenosine A2 receptor stimulation. We applied PDRN on the ischemic flap of rat back and investigated whether it enhances the skin flap survival. A total of 28 Sprague-Dawley rats were divided into 3 groups, namely, PDRN group, control group 1 (no treatment), and group 2 (phosphate-buffered saline injection). On the distally based flap of 3 × 9 cm in size, it was subdermally injected with PDRN or phosphate-buffered saline, which were administered 48 hours prior and immediately after flap elevation. The PDRN group was daily maintained by intraperitoneal administration of PDRN from the postoperative 1st day to 10th day. The mean survival rates of flap in PDRN group [79.5% (6.3%)] are significantly larger than control groups [1, 53.0% (6.9%); 2, 51.7% (6.7%)]. Serial measurements of blood perfusion also showed that the blood flux was significantly increased in almost part of the flap on the 10 days after PDRN injection. The number of CD31 positively stained vessels and expression of VEGF protein were significantly higher in the PDRN group. We propose that administration of PDRN into the ischemic skin flaps increased blood flux to the flap, VEGF expression, and number of capillaries, thereby improving the rat skin flap survival.

Evaluation of the efficacy of microsurgical practice through time factor added protocol: microsurgical training using nonvital material.

PURPOSE: The evaluation of microsurgical technique is often done in an attempt to enhance the skills of surgeons. However, it varies depending on the institution or supervisors. According to some of the research done so far, there are many institutes that enable surgeons to train themselves with enough time but are confronted with some other limiting factors. We have added the time factor and conducted our study on the evaluation of microsurgical techniques. The purpose of this study was to decide whether using a nonvital pig leg saves microsurgical training time and improves microsurgical skill and how effective this method is in an objective assessment. MATERIALS AND METHODS: For 3 pig legs, the full procedure time was calculated 3 times and the anastomosis duration was measured 5 times for a total of 8 trainees. The authors made evaluations conforming to the following protocol. The full procedure time was defined as the time period between when students entered and left the laboratory, including the time for preparation and cleaning up. The anastomosis time included just one anastomosis at the time of vessel cutting. An objective evaluation of vessel anastomosis was performed using a 5-point global rating scale in 6 categories. For suture errors, we calculated the number of broken sutures, broken knots, and broken or damaged needles. After anastomosis, leakage was tested using an infusion pump. For an objective analysis, the study was limited to arterial end-to-end anastomosis and all the parameters were measured by a single trainer. RESULTS: For the full procedure time, 129.0 (13.8) minutes was needed for the first trial, whereas the third trial took 72.4 (11.1) minutes (P < 0.05). For the anastomosis time, the first trial took 47.1 (14.7) minutes, whereas the fifth took 18.0 (2.1) minutes. There was a statistical significance, except between the third and fourth trials. Improvement in the global rating scale was noted with increased procedure frequency. The mean total score (30 points is perfect) was 8.9 (1.5) at the first trial, which improved to 25.0 (0.9). As for the suture errors, 7.5 (1.3) errors were noted on the first trial, which was reduced to 1.6 (0.7) on the fifth trial. CONCLUSIONS: The authors carried out microsurgical training using a protocol that added the time factor to the conventional evaluation studies. Microsurgical practice with pig legs statistically saves time and improves the skill in 3 full procedures including 5 practice end-to-end arterial anastomoses. This is an effective and economic method of developing the basic techniques performed during anastomosis procedures.

A three-dimensional analysis of the relationship among lower facial width, bony width, and masseter muscle volume in subjects with prominent mandible angles.

Despite the fact that a face with a square appearance is determined by surface anatomic features, skin surface parameters and their relationship with inner anatomic features have not been evaluated owing to the challenge of accurately and consistently measuring skin landmarks.We introduce 2 surface distances of the lower face obtained from images of skin and bone thresholds from three-dimensional computed tomographic scans; these were realigned in identical positions using the Frankfurt horizontal plane. The selected parameters were skin surface (LFOP) and bony width (MOP) of the occlusal plane level, skin surface (LFBP) and bony width (MBP) of the bigonial plane level, masseter volume (MV), and soft tissue thickness. Ten subjects with mandible angle flaring and 10 control subjects without flaring were evaluated.The parameters LFOP, LFBP, MBP, and MV showed differences between the study and control groups (P < 0.05). Lower facial width of the occlusal plane was longer than LFBP in both groups (P < 0.005), and MOP was shorter than MBP in the study group (P < 0.005), whereas MOP was greater than MBP in the control group (P < 0.001). Correlation analysis revealed that skin surface width was significantly related to bony width only in the control group (r > 0.6). Masseter volume showed no significant relationship with any skin surface or bony parameter but with soft tissue thickness in the control group (r > 0.6).In conclusion, skin surface widths (LFOP and LFBP) along with MV and bony width differ between patients with flared and nonflared mandibles. Our findings suggest that the skin surface width of the lower face can be used as a valuable landmark.

Transport disc distraction osteogenesis for the reconstruction of a calvarial defect.

PURPOSE: Reconstruction of bone defects is possible through distraction osteogenesis using small bone transport discs. The aim of this study was to evaluate the usability of transport disc distraction osteogenesis (TDDO) in the reconstruction of skull defects in an animal experiment. METHODS: Eleven mongrel female dogs were used. Craniectomy (33 x 15 mm) was performed on both sides of the parietal bone symmetrically. On the experimental site, the 7 x 15-mm transport bone disc was used for TDDO. The control site was left in the defect state. An external distraction device was used. The latency period was 5 days, the rate of distraction was 1 mm/d, and distraction was done for 26 days. After a 6-month consolidation period, a computed tomographic scan was performed. The area of regenerated bone was measured from the computed tomographic scan. The hardness was checked on the regenerated bone and the normal bone. A histologic examination of the regenerated bone was done. RESULT: Eight cases were included in the evaluation, and 3 cases were excluded because they showed early escape of the distraction device. The mean (SD) area of the regenerated bone was 57.1% (26.3) in the experimental site and 41.8% (21.3) in the control site, which was not a statistically significant difference (P > 0.05). The mean (SD) hardness was 0.50 (0.17) MPa in the experiment site and 0.55 (0.29) MPa in the normal calvarial bone; the difference was not statistically significant (P > 0.05). On histologic examination, membranous ossification was found in the regenerated bone in the experimental site. CONCLUSIONS: Transport disc distraction osteogenesis can induce new bone formation with hardness comparable to that of a normal bone. However, the amount of regenerated bone is not sufficient to allow TDDO to be substituted for conventional autogenous bone grafts.

Surgical correction of pseudoainhum in chronic epidermolysis bullosa: a case report.

Pseudoainhum is a rare condition of unknown aetiology that is characterised by the presence of constriction bands of extremities due to a variety of underlying causes that progress to irreversible damage and auto-amputation of the affected digit. Epidermolysis bullosa is a group of disorders characterised by extremely fragile skin and recurrent blister formation resulting from minor mechanical trauma. The association of epidermolysis bullosa with other hand defects, such as hand contracture and pseudosyndactyly, have been reported; however, ainhum-like digital constriction bands have not been reported in association with this disorder. To our knowledge, this is the first reported case of pseudoainhum in association with epidermolysis bullosa and highlights good surgical response obtained with microscopic removal of the recurred constriction band and cross-finger flap to prevent recurrence, relieve symptoms and improve cosmesis.