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Biomedical subjects

D K Ousterhout

Publications and source records attributed to D K Ousterhout.

At least 37 records · Page 2Linked to original sources
PubMed1989

Posttraumatic condylar hyperplasia.

Posttraumatic condylar hyperplasia can result in complex facial asymmetry composed of degrees of condylar and ramus overgrowth, malocclusion, and complementary maxillary deformity. Three patients with unilateral condylar hyperplasia are described to illustrate the scope of surgical and orthodontic treatment required to restore facial symmetry. Condylar hyperplasia with facial asymmetry should be recognized as a possible consequence of condylar injury, and further delineation of the onset and natural history of this deformity could lead to investigations or intervention before the establishment of all the components of the deformity.

Adolescent↗
PubMed1989

Retrognathism.

Retrognathia is a common deformity that generally requires both orthodontics and surgery for correction. The surgical correction of the problem is best completed in the majority of cases with the sagittal splitting osteotomy. While the surgery is generally successful, relapse is a formidable problem. Instrument registration methods for properly positioning the condyles are being developed, but at this time are not totally successful. Lag screw fixation of the segments is very stable and seems to limit relapse but requires a facial incision with a resulting scar. Future technology probably will allow for internal placement of lag screws. Until such techniques are available, the use of intermaxillary fixation followed by an elastics activated registration bite splint to facilitate healing is recommended.

Adult↗
PubMed1987

Aesthetic improvement resulting from craniofacial surgery in craniosynostosis syndromes.

A consecutive series of 21 patients with craniosynostosis syndromes (9 Crouzon's, 6 Pfeiffer's, 6 Apert's) was evaluated for reconstructive postoperative aesthetic improvement resulting from craniofacial surgery (Le Fort III, sliding genioplasty, nasal septal reconstruction and cranioplasty). The same consecutive series of patients had been previously evaluated for stability of Le Fort III advancement. All the patients were assessed at least one year post operatively. Stability of the advancement was confirmed. In the present study, various midline bony and soft tissue profile measurements were obtained from lateral cephalograms. These measurements were compared to similar measurements (standards) in normals. "Normal" standards and "normal" appearance imply harmonious and aesthetically pleasing facial features. This study showed markedly abnormal positions of the selected bony and soft tissue landmarks preoperatively compared to the normal but following surgery the measurements studied approached or were similar to the normal standards. Based on these measurements, the patient's appearance improved significantly following reconstructive craniofacial surgery. Suggestions for additional surgery based on these studies are made.

Acrocephalosyndactylia↗
PubMed1987

Anatomy and development of the pterygopalatomaxillary region, studied in relation to Le Fort osteotomies.

An understanding of the anatomy and postnatal development of the pterygomaxillary region is needed as a basis for timing and completion of Le Fort osteotomies. The present study included a macroscopic and microscopic study of human skull and autopsy material, both materials representing different developmental stages. Finally, Le Fort I procedures were completed on adult cadavers and the pterygomaxillary region studied histologically. The skull material demonstrated an increasing association between the palatine bone and adjacent bones. Disarticulation was possible only in the infantile period; in the late juvenile and the adolescent stages, disarticulation was accompanied by fractures of the heavily interdigitated osseous surfaces. The histological studies confirmed the marked complexity of the suture, and our findings suggest that the palatine bone acts as a buffer between these areas with their differing intrinsic growth patterns. The remodeling processes in the area seem to reflect different functional demands of the bony pharynx and the maxillary complex. These findings, in conjunction with the significant variations in the gross anatomy of the pterygomaxillary area combined with the location of the actual osteotomy in simulated Le Fort I procedures, force consideration of placement of the posterior osteotomy through the maxillary sinus rather than through the pterygomaxillary fissure in adults. If Le Fort procedures are to be completed in children, probable interference in facial growth is of major concern. Therefore the timing of Le Fort procedures before adolescence must be reconsidered.

Adolescent↗
PubMed1987

Feminization of the forehead: contour changing to improve female aesthetics.

Anthropologists have identified those characteristics which enable them to differentiate the male from the female skull. Some women have masculine skeletal characteristics which, if changed, would improve their facial appearance. Changing the skeletal configuration through bony contouring of the craniofacial skeleton for aesthetic purposes is a natural spinoff of craniomaxillofacial surgery. Techniques for sculpturing the masculine characteristics present in the foreheads of some females are discussed. The deformity has been divided into three subdivisions. Group 1 patients can be treated through bony contouring alone; group 2 patients require bony contouring in conjunction with a methyl methacrylate cranioplasty; and group 3 are those patients with a more severe deformity requiring osteotomies. The technique, results, complications, and patient acceptance are discussed.

Esthetics↗
PubMed1987

Maxillary hypoplasia secondary to midfacial trauma in childhood.

Three normal children who suffered midfacial trauma and developed midfacial retrusion that would require Le Fort III advancements for correction of the deformity are described. The common denominator in these three cases seems to be an injury to the medial facial structure including the nasal septum. It is concluded that midfacial fractures in childhood may be a cause of subsequent midfacial hypoplasia.

Adolescent↗
PubMed1987

Surgical treatment of the jaw deformities in hemifacial microsomia.

The surgical treatment of the mandibular and maxillary deformities in patients with hemifacial microsomia requires some form of mandibular lengthening. This is usually either via ramus interpositional bone grafting or end-on bone grafting. In a few cases, ramus lengthening may be completed by a sagittal split. Once the mandible has been reconstructed, the maxillary surgery can be completed. In previous forms of treatment, mandibular bone grafting was completed without regard to function and neuromuscular adaptation and a significant percentage of such procedures completed failed. Egil Harvold and his colleagues developed a method by which changes in form and function are co-ordinated by using a functional appliance resulting in neuromuscular adaptation. After the bone grafting is completed, as the second of six phases of treatment, a specially designed registration bite-block further facilitates neuromuscular adaptation by controlling mandibular movements (function), but in addition it protects the bone graft from excessive forces thereby aiding in osteogenesis (third phase). The theoretical basis, classification of deformities, and phases of treatment developed are presented and the surgery is described in detail. The results of a consecutive group of patients treated by these methods is then presented. While this form of treatment is not the only one possible, it is the only one that has been tested in the laboratory, proven in patient care, and stood the test of time.

Adolescent↗
PubMed1987

Autogeneic skull bone grafts to reconstruct large or complex skull defects in children and adolescents.

Autogeneic split or free skull bone grafts harvested at the time of operation were used to repair large or complex skull defects in 19 children; in 2 children, autogeneic fresh rib grafts were also used. Follow-up examinations for periods of 1 and 7 years showed that the use of autogeneic grafts is superior to the use of materials such as acrylic or metals for cranioplasty in children.

Adolescent↗
PubMed1987

Craniosynostosis and hydrocephalus.

Ten cases of craniosynostosis associated with hydrocephalus were found in a retrospective review of 250 cases of children with craniosynostosis. Four children had Pfeiffer's syndrome, 3 had Crouzon's syndrome, 2 had kleeblattschädel with multiple anomalies and therefore could not be classified into a definite syndrome, and 1 had isolated sagittal synostosis. Of these 10 children, 5 had kleeblattschädel, two with Crouzon's syndrome, one with Pfeiffer's syndrome, and 2 with multiple anomalies. In all patients, hydrocephalus was controlled by a shunting procedure. Possible causes of hydrocephalus in association with craniosynostosis are discussed.

Adolescent↗
PubMed1986

Stability of the maxilla after Le Fort III advancement in craniosynostosis syndromes.

The purpose of this study was to assess long-term position of the maxilla after surgical Le Fort III advancement of midfacial structures in patients with craniosynostosis syndromes. Data from preoperative, short and long-term postoperative lateral head films on 21 consecutive patients with Crouzon's syndrome, Pfeiffer's syndrome, or Apert's syndrome were analyzed. A method of evaluating the position of the postoperative maxilla on lateral head films is described. On average, the position of the maxilla did not change significantly in the postoperative periods studied, although some individual variation was demonstrated. Postoperative management, utilizing a registration bite splint after the intermaxillary fixation has been removed, similar to our treatment following bone grafting procedures in patients with hemifacial microsomia, is described.

Acrocephalosyndactylia↗
PubMed1986

Factors affecting long-term results in hemifacial microsomia.

Mandibular malformations in patients with hemifacial microsomia are described and six phases of treatment outlined. Growth of the malformed mandibular ramus in response to functional appliance treatment was studied in 15 subjects with type I mandibular malformations. It was found that length increase of the affected side during the treatment period was not significantly different from the growth of the other side. Changes in length of the affected side of the mandible following surgical repositioning and bonegrafting was assessed in 25 consecutive cases. In 10 of these subjects, the surgical procedure was done during the growth period and in 15 of them after growth had ceased. In the still growing subjects, there was additional length increase of the reconstructed mandibular ramus, but on an average, less than on the side which had normal temporomandibular joint structures. In seven cases, the length increase was similar on the two sides ( +/- 2 mm) or greater on the affected side, and the established symmetry was maintained. In three subjects, there was recurrence of asymmetry, which in two individuals was corrected by a second surgical lengthening of the mandible. There was minimal loss in length of the reconstructed mandibular ramus in the nongrowing subjects and the established mandibular position was maintained.

Activator Appliances↗
PubMed1985

Clinical experience in cranial and facial reconstruction with demineralized bone.

While autogenous bone is the preferred building material for skull and facial bone reconstruction, it has definite disadvantages that make the continued use of alloplastic materials inviting. Studies in the past few years have generated considerable publicity about demineralized bone as a possible substitute for autogenous bone. A clinical study using commercially available, demineralized bone in 25 patients with a follow-up period of 6 to 18 months was completed. Results indicated that where there was a functional need or the environment (tissue envelope) was satisfactory, the demineralized bone induced osteogenesis; otherwise, there was considerable resorption of the implant. This implies that, for filling bony defects or reconstructing posttraumatic deformities, the implant generally worked fairly well, while attempts to augment bony contours, especially large areas such as the forehead, were generally not satisfactory. Even where there was a functional need for bone, a significant degree of unpredictable resorption of the demineralized implant occurred.

Adult↗
PubMed1984

Computerized tomography of cranial sutures. Part 1: Comparison of suture anatomy in children and adults.

Knowledge of normal suture anatomy and development is vital in order to understand abnormal suture development and to be able to distinguish sutures radiographically from normal anatomical structures and possible skull fractures. The anatomy of the sutures and synchondroses of 150 normal pediatric and adult patients was studied using high-resolution computerized tomography scanning. Sutures of both the calvaria and skull base were most accurately identified in axial and coronal high-resolution thin-section scans when bone window algorithms were used. Developmental changes of the sutures and synchodroses , the inner and outer tables, and the diploic space were all well delineated. Vault sutures could be identified routinely in children, but their presence in adults varied considerably. With increasing age, parasutural sclerosis developed and sutures were more closely apposed.

Adolescent↗
PubMed1984

Computerized tomography of cranial sutures. Part 2: Abnormalities of sutures and skull deformity in craniosynostosis.

Preoperative computerized tomographic (CT) scans of 24 children who had surgery for either single or multiple craniosynostoses were compared with skull radiographs and operative and pathological findings. In addition to providing accurate imaging of calvarial and skull base deformities secondary to premature suture closure, high-resolution CT with bone definition algorithms supplied valuable detail of anatomical changes at the abnormally developed suture. The CT findings varied with the location of the suture. Thickened bony ridges predominated at the sagittal suture, focal bone thickening and erosions were more likely to be found at the metopic suture, and parasutural sclerosis was the prevalent finding on one side of the lambdoid suture. No evidence of the suture could be detected in the majority of patients with complete coronal craniosynostosis. Radiographs of the skull were shown to be a relatively insensitive means of imaging the zone of limited fusion, especially the lambdoid suture. An excellent correlation was found between the CT scan and the operative and pathological findings. There was histological evidence of progressive suture fusion in virtually all patients. An asymmetrically narrowed lucent zone with parasutural sclerosis or bony ridges seen on CT scans correlated well with fibrous union of the suture found on histological examination. The authors conclude that high-definition CT used in conjunction with bone windows and thin and coronal slices for the evaluation of sagittal sutures is a useful imaging method for the evaluation of craniosynostosis.

Cranial Sutures↗
PubMed1983

Nasal airway function as it relates to the timing of mid and lower facial osteotomies.

It has been established in primate studies that mouth-breathing can affect lower facial development. We submit that mouth-breathing has a similar effect on human development--specifically, that chronic mouth-breathing during growth contributes to long-face syndrome. When reconstructive surgery is contemplated for this deformity, we believe that the sequence of surgical steps is important and that particular attention should be given to enhancing nasal respiration. The possibility that mouth-breathing is a factor in relapse following mandibular surgery is discussed.

Adolescent↗
PubMed1982

The role of the lateral canthal tendon in lower eyelid laxity.

Measurements of lower eyelid length were completed to determine if the length of the lower eyelid increased with advancing age. The results support the that the lower eyelid indeed does not get longer with aging. In two groups of 100 patients each, at either end of the adult age spectrum, there were no statistical differences in the lengths of the lower eyelids. Our data support the concept that the lateral canthal tendon stretches with advancing age and allows the lateral canthus to drift medially, thus allowing for shortening of the horizontal palpebral fissure and contributing to the marked laxity of the lower eyelids often seen in older individuals. More attention should be paid to this etiologic factor in the surgical correction of lower eyelid laxity.

Adult↗