• Journal of Korean Neurosurgical Society
• /
• v.57 no.5
• /
• pp.350-358
• /
• 2015

Objective : To evaluate the morphometry of the anterior thalamoperforating arteries (ATPA). Methods : A microanatomical study was performed in 79 specimens from 42 formalin-fixed adult cadaver brains. The origins of the ATPAs were divided into anterior, middle, and posterior segments according to the crowding pattern. The morphometry of the ATPAs, including the premammillary artery (PMA), were examined under a surgical microscope. Results : The anterior and middle segments of the ATPAs arose at mean intervals of $1.75{\pm}1.62$ mm and $5.86{\pm}2.05$ mm from the internal carotid artery (ICA), and the interval between these segments was a mean of $3.17{\pm}1.64$ mm. The posterior segment arose at a mean interval of $2.43{\pm}1.46$ mm from the posterior cerebral artery (PCA), and the interval between the middle and posterior segments was a mean of $3.45{\pm}1.39$ mm. The mean numbers of perforators were $2.66{\pm}1.19$, $3.03{\pm}1.84$, and $1.67{\pm}0.98$ in the anterior, middle, and posterior segments, respectively. The PMA originated from the middle segment in 66% of cases. A perforator-free zone was located >2 mm from the ICA in 30.4% and >2 mm from the PCA in 67.1% of cases. Conclusion : Most perforators arose from the anterior and middle segments, within the anterior two-thirds of the posterior communicating artery (PCoA). The safest perforator-free zone was located closest to the PCA. These anatomical findings may be helpful to verify safety when treating lesions around the PCoA and in the interpeduncular fossa.

• Journal of Korean Neurosurgical Society
• /
• v.47 no.3
• /
• pp.169-173
• /
• 2010

Objective : The normal anatomic relationships characteristic of the pituitary stalk area were previously thought to involve only one location. The purpose of this study was to re-evaluate the anatomic location of the pituitary stalk and possible varying locations in relation to the tuberculum sellae and dorsum sellae using morphometric evaluation and anatomic dissection of human cadaveric specimens. The surgical implications of the variations are discussed. Methods : The calvaria were removed via routine autopsy dissections, and the brains were removed from the skull while preserving the pituitary stalk. The diaphragma sellae, tuberculum sellae, and the location of the pituitary stalk were examined in 60 human cadaveric heads obtained from fresh adult cadavers. Empty sellae were excluded. Results : The openings of the diaphragma sellae averaged $6.62{\pm}1.606mm$ (range, 3-9 mm). The distance between the tuberculum sellae and the posterior part of the pituitary stalk was 1 to 8 mm. The upper face of the diaphragma sellae appeared flat in 26 (43%), concave in 24 (40%), and convex in 6 cases (10%), with a prominent tuberculum sellae in 4 cases (7%). The location of the chiasm was normal in 47 cases (78%), with a prefixed chiasm in 3 cases (5%) and a postfixed chiasm (17%) in the 10 cases. Four cadaver specimens had prominent tuberculum sellae and other parameters were not evaluated. Conclusion : When opening the chiasmatic cistern, neurosurgeons should be aware about the relationship between the pituitary stalk and the surrounding structures to prevent inadvertent injury to the pituitary stalk.

• Journal of Korean Neurosurgical Society
• /
• v.47 no.3
• /
• pp.174-179
• /
• 2010

Objective : Cricothyrotomy and tracheostomy are performed by physicians in various disciplines. It is important to know the comprehensive anatomy of the laryngotracheal region. Hemorrhage, esophageal injury, recurrent laryngeal nerve injury, pneumothorax, hemothorax, false passage of the tube and tracheal stenosis after decannulation are well known complications of the cricothyrotomy and tracheostomy. Cricothyrotomy and tracheostomy should be performed without complications and as quickly as possible with regards the patients' clinical condition. Methods : A total of 40 cadaver necks were dissected in this study. The trachea and larynx and the relationship between the trachea and larynx and the surrounding structures was investigated. The tracheal cartilages and annular ligaments were counted and the relationship between tracheal cartilages and the thyroid gland and vascular structures was investigated. We performed cricothyrotomy and tracheostomy in eleven cadavers while simulating intensive care unit conditions to determine the duration of those procedures. Results : There were 11 tracheal cartilages and 10 annular ligaments between the cricoid cartilage and sternal notch. The average length of trachea between the cricoid cartilage and the suprasternal notch was 6.9 to 8.2 cm. The cricothyroid muscle and cricothyroid ligament were observed and dissected and no vital anatomic structure detected. The average length and width of the cricothyroid ligament was 8 to 12 mm and 8 to 10 mm, respectively. There was a statistically significant difference between the surgical time required for cricothyrotomy and tracheostomy (p < 0.0001). Conclusion : Tracheostomy and cricothyrotomy have a low complication rate if the person performing the procedure has thorough knowledge of the neck anatomy. The choice of tracheostomy or cricothyrotomy to establish an airway depends on the patients' clinical condition, for instance; cricothyrotomy should be preferred in patients with cervicothoracal injury or dislocation who suffer from respiratory dysfunction. Furthermore; if a patient is under risk of hypoxia or anoxia due to a difficult airway, cricothyrotomy should be preferred rather than tracheostomy.

• Imaging Science in Dentistry
• /
• v.40 no.1
• /
• pp.15-23
• /
• 2010

Purpose : This study was designed to compare the effective doses from low-dose and standard-dose multi-detector CT (MDCT) scanning protocols and evaluate the image quality and the spatial resolution of the low-dose MDCT protocols for clinical use. Materials and Methods : 6-channel MDCT scanner (Siemens Medical System, Forschheim, Germany), was used for this study. Protocol of the standard-dose MDCT for the orthodontic analysis was 130 kV, 35 mAs, 1.25 mm slice width, 0.8 pitch. Those of the low-dose MDCT for orthodontic analysis and orthodontic surgery were 110 kV, 30 mAs, 1.25 mm slice width, 0.85 pitch and 110 kV, 45 mAs, 2.5 mm slice width, 0.85 pitch. Thermoluminescent dosimeters (TLDs) were placed at 31 sites throughout the levels of adult female ART head and neck phantom. Effective doses were calculated according to ICRP 1990 and 2007 recommendations. A formalin-fixed cadaver and AAPM CT performance phantom were scanned for the evaluation of subjective image quality and spatial resolution. Results : Effective doses in ${\mu}Sv$ ($E_{2007}$) were 699.1, 429.4 and 603.1 for standard-dose CT of orthodontic treatment, low-dose CT of orthodontic analysis, and low-dose CT of orthodontic surgery, respectively. The image quality from the low-dose protocol were not worse than those from the standard-dose protocol. The spatial resolutions of both standard-dose and low-dose CT images were acceptable. Conclusion : From the above results, it can be concluded that the low-dose MDCT protocol is preferable in obtaining CT images for orthodontic analysis and orthodontic surgery.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.19 no.1
• /
• pp.7-15
• /
• 2003

This study used FEM(Finite Element method) based on micro-CT images to see the effects of occlusal force distribution with varying bone density and structure. the mandibular premolar region from human cadaver, thickness of 10mm was imaged using micro-CT. the cross sectional images were taken every $10{\mu}m$. these were reconstructed and the longitudinal image at the mid point of mesiodistal of the speciman was obtained for the specimen for the FEM. The stress disribution produced by a vertical force at 100N and 100N horizontal were analyzed by MSC Nastran FEM Package. according to the result of this study the occlusal force distribution depends on the structure of cancellus bone and for further information on the occlusal force distribution on the tooth and the surrounding structure requires further studies on cancellus bone structure. CEJ of all model show the highest peak and region whice meet teeth and bone show second high peak. Original model and cortical bone add model show different stress distribution. Stress distribution changed according to bone structures and densities.

• Imaging Science in Dentistry
• /
• v.45 no.1
• /
• pp.23-29
• /
• 2015

Purpose: This study aimed to assess the reliability of measurements performed on three-dimensional (3D) virtual models of maxillary defects obtained using cone-beam computed tomography (CBCT) and 3D optical scanning. Materials and Methods: Mechanical cavities simulating maxillary defects were prepared on the hard palate of nine cadavers. Images were obtained using a CBCT unit at three different fields-of-views (FOVs) and voxel sizes: 1) $60{\times}60mm$ FOV, $0.125mm^3$ ($FOV_{60}$); 2) $80{\times}80mm$ FOV, $0.160mm^3$ ($FOV_{80}$); and 3) $100{\times}100mm$ FOV, $0.250mm^3$ ($FOV_{100}$). Superimposition of the images was performed using software called VRMesh Design. Automated volume measurements were conducted, and differences between surfaces were demonstrated. Silicon impressions obtained from the defects were also scanned with a 3D optical scanner. Virtual models obtained using VRMesh Design were compared with impressions obtained by scanning silicon models. Gold standard volumes of the impression models were then compared with CBCT and 3D scanner measurements. Further, the general linear model was used, and the significance was set to p=0.05. Results: A comparison of the results obtained by the observers and methods revealed the p values to be smaller than 0.05, suggesting that the measurement variations were caused by both methods and observers along with the different cadaver specimens used. Further, the 3D scanner measurements were closer to the gold standard measurements when compared to the CBCT measurements. Conclusion: In the assessment of artificially created maxillary defects, the 3D scanner measurements were more accurate than the CBCT measurements.

• Archives of Plastic Surgery
• /
• v.41 no.1
• /
• pp.50-56
• /
• 2014

Background The aim of this study was to determine the efficacy of lateral intercostal artery perforator-based adipofascial free flaps for facial reconstruction in patients with facial soft tissue deficiency. Methods We conducted a retrospective study of five consecutive patients diagnosed with facial soft tissue deficiency who underwent operations between July 2006 and November 2011. Flap design included the area containing the perforators. A linear incision was made along the rib, which had the main intercostal pedicle. First, we dissected below Scarpa's fascia as the dorsal limit of the flap. Then, the adipofascial flap was elevated from the medial to the lateral side, including the perforator that pierces the serratus anterior muscle after emerging from the lateral intercostal artery. After confirming the location of the perforator, pedicle dissection was performed dorsally. Results Dominant perforators were located on the sixth to eighth intercostal space, and more than four perforators were found in fresh-cadaver angiography. In the clinical case series, the seventh or eighth intercostal artery perforators were used for the free flaps. The mean diameter of the pedicle artery was 1.36 mm, and the mean pedicle length was 61.4 mm. There was one case of partial fat necrosis. No severe complications occurred. Conclusions This is the first study of facial contour reconstruction using lateral intercostal artery perforator-based adipofascial free flaps. The use of this type of flap was effective and can be considered a good alternative for restoring facial symmetry in patients with severe facial soft tissue deficiency.

• Archives of Plastic Surgery
• /
• v.40 no.4
• /
• pp.312-319
• /
• 2013

Over the past decade, driven by advances in educational theory and pressures for efficiency in the clinical environment, there has been a shift in surgical education and training towards enhanced simulation training. Microsurgery is a technical skill with a steep competency learning curve on which the clinical outcome greatly depends. This paper investigates the evidence for educational and training interventions of traditional microsurgical skills courses in order to establish the best evidence practice in education and training and curriculum design. A systematic review of MEDLINE, EMBASE, and PubMed databases was performed to identify randomized control trials looking at educational and training interventions that objectively improved microsurgical skill acquisition, and these were critically appraised using the BestBETs group methodology. The databases search yielded 1,148, 1,460, and 2,277 citations respectively. These were then further limited to randomized controlled trials from which abstract reviews reduced the number to 5 relevant randomised controlled clinical trials. The best evidence supported a laboratory based low fidelity model microsurgical skills curriculum. There was strong evidence that technical skills acquired on low fidelity models transfers to improved performance on higher fidelity human cadaver models and that self directed practice leads to improved technical performance. Although there is significant paucity in the literature to support current microsurgical education and training practices, simulated training on low fidelity models in microsurgery is an effective intervention that leads to acquisition of transferable skills and improved technical performance. Further research to identify educational interventions associated with accelerated skill acquisition is required.

• Archives of Plastic Surgery
• /
• v.44 no.2
• /
• pp.136-143
• /
• 2017

Background The goal of this study was to investigate the anatomy of the peroneal artery and its perforators, and to report the clinical results of reconstruction with peroneal artery perforator flaps. Methods The authors dissected 4 cadaver legs and investigated the distribution, course, origin, number, type, and length of the perforators. Peroneal artery perforator flap surgery was performed on 29 patients. Results We identified 19 perforators in 4 legs. The mean number of perforators was 4.8 per leg, and the mean length was 4.8 cm. Five perforators were found proximally, 9 medially, and 5 distally. We found 12 true septocutaneous perforators and 7 musculocutaneous perforators. Four emerged from the posterior tibia artery, and 15 were from the peroneal artery. The peroneal artery perforator flap was used in 29 patients. Retrograde island peroneal flaps were used in 8 cases, anterograde island peroneal flaps in 5 cases, and free peroneal flaps in 16 cases. The mean age was 59.9 years, and the defect size ranged from $2.0cm{\times}4.5cm$ to $8.0cm{\times}8.0cm$. All the flaps survived. Five flaps developed partial skin necrosis. In 2 cases, a split-thickness skin graft was performed, and the other 3 cases were treated without any additional procedures. Conclusions The peroneal artery perforator flap is a good alternative for the reconstruction of soft tissue defects, with a constant and reliable vascular pedicle, thin and pliable skin, and the possibility of creating a composite tissue flap.

• Archives of Plastic Surgery
• /
• v.47 no.6
• /
• pp.604-612
• /
• 2020

Background Due to the anatomical complexity of the deep temporal fascia (DTF), practical guidelines for its safe harvest are lacking. However, since the upper temporal compartment (UTC) contains no vital structures, it may provide safe access for DTF harvest. This study aimed to identify the anatomical structures of the temporal compartment in Asian cadavers and to measure their dimensions to enable safe DTF harvest. Methods The anatomical structures surrounding the temporal compartment were identified in 27 hemifaces from 15 Korean cadavers. After dissection, digital images were acquired and craniometric landmarks were placed upon them to identify the boundaries of the temporal compartment. The horizontal and vertical lengths of the temporal compartment were measured and their surface areas were computationally assessed. Subsequently, differences in the results by sex were evaluated. Results The five-layer anatomical structure of the UTC was clearly visualized. The UTC was bounded by the temporal septa superiorly and inferiorly, the innominate fascia laterally, and the DTF medially. No vital structures were present within the UTC. The vertical and horizontal lengths of the UTC were 6.41±0.67 cm and 10.44±0.83 cm, respectively, and the surface area of the UTC was 48.52±5.65 ㎠. No statistically significant differences were observed in any dimensions between male and female patients. Conclusions During rhinoplasty, DTF can be harvested as an autologous graft material from the UTC. An anatomical understanding of the UTC will aid in the safe and simple harvest of a sufficient amount of DTF.