共查询到20条相似文献,搜索用时 0 毫秒
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B M Jones 《BMJ (Clinical research ed.)》1986,293(6539):89-90
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Wong GB Stokes RB Stevenson TR Whetzel TP Saunders CJ 《Plastic and reconstructive surgery》1999,103(3):970-971
Static suspension remains an option for certain patients with facial paralysis. Endoscopically assisted facial suspension obviates the need for a counter-incision at the oral commissure to distally inset the fascia lata graft as described in the standard technique. The endoscopic technique is simple, allows secure placement of perioral fascial strips, and can be performed as an outpatient. 相似文献
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《Journal of Biomedical Engineering》1981,3(2):143-146
A principle for secondary instrumental spinal distraction by a rod appliance of the Knodt and Harrington types is described. The principle entails the rotation of the screw rod by wire traction. The wire is, in a secondary procedure, unwound from a wire barrel mounted onto the screw rod in the primary operative procedure. The study describes the devices employed, modified according to the wire traction—instrument distraction principle Previous results from intra-vital studies of the Harrington instrumentation have been reported from experiments performed2. Thus, a final distraction force of 18 kp effected for correction of a scoliosis curvature, was taken as a value of distraction prior to secondary instrumental distraction by wire traction. In the extra vital study, the wire traction was adjusted to surmount a compressive force of 20 kpby means of a Bessmann weight scale. Wire traction created a distraction force of 39.5 kp, and a metric distraction, from the position resulting from 20 kp distraction to that resulting from 39.5 kp distraction, of 2.8 mm, which was considered to affect the prevalling scoliosis geometry to a considerable and sufficient extent. 相似文献
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Reina-Romo E Gómez-Benito MJ García-Aznar JM Domínguez J Doblaré M 《Biomechanics and modeling in mechanobiology》2009,8(4):323-335
Distraction osteogenesis is a useful technique aimed at inducing bone formation in widespread clinical applications. One of
the most important factors that conditions the success of bone regeneration is the distraction rate. Since the mechanical
environment around the osteotomy site is one of the main factors that affects both quantity and quality of the regenerated
bone, we have focused on analyzing how the distraction rate influences on the mechanical conditions and tissue regeneration.
Therefore, the aim of the present work is to explore the potential of a mathematical algorithm to simulate clinically observed
distraction rate related phenomena that occur during distraction osteogenesis. Improvements have been performed on a previous
model (Gómez-Benito et al. in J Theor Biol 235:105–119, 2005) in order to take into account the load history. The results
obtained concur with experimental findings: a slow distraction rate results in premature bony union, whereas a fast rate results
in a fibrous union. Tension forces in the interfragmentary gap tissue have also been estimated and successfully compared with
experimental measurements. 相似文献
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Toward CT-based facial fracture treatment 总被引:2,自引:0,他引:2
P N Manson B Markowitz S Mirvis M Dunham M Yaremchuk 《Plastic and reconstructive surgery》1990,85(2):202-12; discussion 213-4
Facial fractures have formerly been classified solely by anatomic location. CT scans now identify the exact fracture pattern in a specific area. Fracture patterns are classified as low, middle, or high energy, defined solely by the pattern of segmentation and displacement in the CT scan. Exposure and fixation relate directly to the fracture pattern for each anatomic area of the face, including frontal bone, frontal sinus, zygoma, nose, nasoethmoidal-orbital region, midface, and mandible. Fractures with little comminution and displacement were accompanied by subtle symptoms and required simple treatment; middle-energy injuries were treated by standard surgical approaches and rigid fixation. Highly comminuted fractures were accompanied by dramatic instability and marked alterations in facial architecture; only multiple surgical approaches to fully visualize the "buttress" system provided alignment and fixation. Classification of facial fractures by (1) anatomic location and (2) pattern of comminution and displacement define refined guidelines for exposure and fixation. 相似文献
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Validation of in vivo assessment of facial soft-tissue volume changes and clinical application in midfacial distraction: a technical report 总被引:3,自引:0,他引:3
Nkenke E Langer A Laboureux X Benz M Maier T Kramer M Häusler G Kessler P Wiltfang J Neukam FW 《Plastic and reconstructive surgery》2003,112(2):367-380
The purpose of this study was to validate the assessment of visible volume changes of the facial soft tissue with an optical three-dimensional sensor and to introduce new parameters for the evaluation of the soft-tissue shape achieved from three-dimensional data of selected cases of midfacial distraction. Images of a truncated cone of known volume were assessed repeatedly with an optical three-dimensional sensor based on phase-measuring triangulation to calculate the volume. Two cubic centimeters of anesthetic solution was injected into the right malar region of 10 volunteers who gave their informed consent. Three-dimensional images were assessed before and immediately after the injections for the assessment of the visible volume change. In five patients who underwent midfacial distraction after a high quadrangular Le Fort I osteotomy, three-dimensional scans were acquired before and 6 and 24 months after the operation. The visible soft-tissue volume change in the malar-midfacial area and the mean distance of the accommodation vector that transformed the preoperative into the postoperative surface were calculated. The volume of the truncated cone was 235.26 +/- 1.01 cc, revealing a measurement uncertainty of 0.4 percent. The injections of anesthetic solution into the malar area resulted in an average visible volume change of 2.06 +/- 0.06 cc. The measurement uncertainty was 3 percent. In the five patients, the average distance of maxillary advancement was 6.7 +/- 2.3 mm after 6 months and 5.4 +/- 3.0 mm after 2 years. It was accompanied by a mean visible volume increase of 8.92 +/- 5.95 cc on the right side and 9.54 +/- 4.39 cc on the left side after 6 months and 3.54 +/- 3.70 cc and 4.80 +/- 3.47 cc, respectively, after 2 years. The mean distance of the accommodation vector was 4.41 +/- 1.94 mm on the right side and 4.74 +/- 1.32 mm on the left side after 6 months and 1.62 +/- 1.96 mm and 2.16 +/- 1.52 mm, respectively, after 2 years. The assessment of visible volume changes by optical three-dimensional images can be carried out with considerable accuracy. The determination of volume changes and accompanying accommodation vectors completes the cephalometric analysis during the follow-up of patients undergoing midfacial distraction. The new parameters will help to assess normative soft-tissue data on the basis of three-dimensional imaging with a view to an improved three-dimensional prediction of the operative outcome of orthognathic surgery. 相似文献
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The treatment of facial paralysis is generally considered to have been nonsurgical until the end of the nineteenth century. However, the authors discovered recently that already in the 1840s the celebrated German facial reconstructive surgeons Dieffenbach and von Langenbeck applied the technique of subcutaneous myotomy to healthy facial muscles to reestablish balance in the chronically paralyzed faces of their patients. They performed their operations at a time when anesthesia, asepsis, antisepsis, and antibiotics had not yet been introduced into surgery. It is concluded that Dieffenbach and von Langenbeck were the first, in recorded history, to develop a surgical way to treat irreversible facial paralysis. As their principles are still being used in surgical practice, they cannot be regarded as antiquated, which illustrates the difficulties that reconstructive surgeons still experience in the treatment of irreversible facial paralysis. 相似文献
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Anthropometric measurements of the endoscopic eyebrow lift in the treatment of facial paralysis 总被引:2,自引:0,他引:2
Endoscopic eyebrow lift was performed on 51 patients presenting with eyebrow ptosis due to facial paralysis. The resulting anthropometric measurements of eyebrow position were analyzed statistically to evaluate the effectiveness of this method. When preoperative eyebrow differences between the paralyzed and nonparalyzed sides were measured, the average difference at midpoint was 4.4 mm, and at the highest point, 4.6 mm. When the same points were measured postoperatively, the average difference at midpoint was 2.4 mm, and at the highest point, 2.3 mm. The difference in eyebrow height between the paralyzed and nonparalyzed sides correlated positively with age, both preoperatively and postoperatively. However, differences between preoperative and postoperative eyebrow height (which reflects the effectiveness of endoscopic eyebrow lift) at the highest point did not correlate with age and at the midpoint displayed a slightly negative correlation with age. These results suggest that endoscopic eyebrow lift is effective among young patients whose eyebrow ptosis is minor and is relatively ineffective among elderly patients whose eyebrow ptosis is severe. The conventional method of juxta-brow excision is indicated for elderly patients, for whom the operative scar is almost inconspicuous. 相似文献
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Tissue expansion can be a valuable tool in the reconstruction of soft-tissue defects in craniofacial clefts. To our knowledge, there have been no reports in the literature of the use of tissue expanders to help solve this problem. We report the case of a child with an atypical Tessier no. 3 craniofacial cleft who had a forehead tissue expander placed, inflated, and thus used to provide sufficient local facial skin for repair of the soft-tissue defect. 相似文献
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