Biomedical subjects

Stephen B Baker

Publications and source records attributed to Stephen B Baker.

4 recordsLinked to original sources

PubMed2004

Prevention of venous thromboembolism in the plastic surgery patient.

The term venous thromboembolism refers to a spectrum of disease that includes deep venous thrombosis and pulmonary embolism. Both deep venous thrombosis and pulmonary embolism are often clinically silent and thus difficult to diagnose, which leads to a substantial delay in treatment that results in high rates of morbidity and mortality. The purposes of this article are to help physicians determine the proper venous thromboembolism prophylaxis and to simplify the complex problem of treating venous thromboembolism. The tools provided in this article will help expedite and clarify the decision-making process.

Adult↗

PubMed2002

Immediate versus delayed midface distraction in a primate model using a new intraoral internal device.

The theoretic advantage of distraction osteogenesis of the craniofacial skeleton, especially in cases of severe midface retrusion and in the presence of maxillary scarring, is prevention of relapse following significant advancements. The purpose of this study is to demonstrate the utility of a new low-profile, intraoral, internal device for midface distraction at the conventional or high Le Fort I level. In addition, the present study compares the efficacy of immediate versus delayed distraction on subsequent maxillary relapse. Four adult rhesus Macaca mulatta monkeys were divided into two groups. Group 1 underwent immediate midface distraction; group 2 underwent delayed distraction. All four monkeys underwent a modified Le Fort I osteotomy through an upper buccal sulcus incision and bilateral application of the intraoral midface distraction devices. No other osteotomies or incisions were necessary. Immediate distraction, performed in group 1, entailed intraoperative activation of the devices and distraction of 10 mm followed by a 5-day lag period before postoperative activation and distraction of an additional 10 mm at the rate of 1 mm/day. Delayed distraction, performed in group 2, entailed a 5-day postoperative lag period before device activation and distraction of 20 mm at the rate of 1 mm/day. Both groups thus underwent 20 mm of midface distraction. All devices were removed 6 weeks after completion of distraction. All monkeys tolerated the devices and daily distraction uneventfully. On the basis of serial cephalograms and dental models obtained throughout the experimental period, there was no evidence of relapse in either the immediate or delayed groups 6 months after distraction. In addition, on the basis of histologic, ultrastructural, and dry skull analysis, no significant differences were observed in the quality of regenerate bone obtained when comparing the immediate and delayed distraction groups. Significant midface advancement is thus feasible using this new internal, intraoral distraction device, which presents several advantages over other internal devices that require coronal incisions and additional osteotomies to achieve midface advancement. In addition, immediate distraction may abbreviate the distraction period without adverse sequelae.

Animals↗

PubMed2002

Applications of a new carbonated calcium phosphate bone cement: early experience in pediatric and adult craniofacial reconstruction.

Hydroxyapatite cements have recently been employed as bone substitutes in craniofacial reconstruction. They are easily applied, nonresorbable, available in unlimited quantity, and eliminate donor-site morbidity. Norian CRS (craniofacial repair system) is a new carbonated calcium phosphate paste that is unique in that it more closely resembles bone than do traditional hydroxyapatite pastes. Norian is a low-order crystalline apatite soluble at a low pH, facilitating its resorption and replacement by host bone. The cement was first used for craniofacial surgery in North America at the Children's Hospital of Philadelphia. This report presents the authors' experience with this bone substitute in both pediatric and adult craniofacial reconstruction. Sixteen adult and pediatric patients underwent craniofacial reconstruction involving the use of carbonated calcium phosphate paste for correction of defects that required from 5 to 110 g of carbonated calcium phosphate paste (mean, 28.5 g). The patients were all followed for a minimum of 14 months. Minor complications included one case of infection and two cases involving cement microfragmentation. In the authors' experience, carbonated calcium phosphate paste has proved to be an excellent alloplastic material for osseous augmentation and reconstruction in the craniofacial skeleton. Few problems were encountered using this material; no significant morbidity was encountered. Although this material seems to be promising as a bone substitute, further follow-up will be necessary to evaluate its potential role in craniofacial surgery.

Adolescent↗

PubMed2002

Delayed cranial vault reconstruction for sagittal synostosis in older children: an algorithm for tailoring the reconstructive approach to the craniofacial deformity.

An algorithm for the management of sagittal synostosis in older children who underwent delayed cranial vault reconstruction is presented. This algorithm tailors the surgical approach to the specific craniofacial deformity present in each case. The scaphocephalic deformity characteristic of sagittal synostosis varies significantly when presentation is delayed beyond the first year of life, the time during which reconstruction is usually performed. Sixteen patients with sagittal synostosis who presented after 12 months of age, and were a mean of 3.2 years of age at the time of cranial vault reconstruction, were reviewed. Four patients demonstrated preoperative symptoms and objective findings indicative of increased intracranial pressure, including frequent headaches and emesis, papilledema, or digital markings on computed tomographic scan. Each of the 16 patients underwent either (1) single-stage total vault reconstruction with or without concomitant fronto-orbital expansion; (2) two-stage total vault reconstruction with anterior two-thirds vault expansion followed by transverse occipital expansion and recession a mean of 8.7 months later; or (3) anterior two-thirds vault reconstruction with or without fronto-orbital expansion. In each case, the extent of the scaphocephalic deformity determined the procedure used. The presence of severe frontal bossing associated with transverse restriction of the orbitotemporal region was an indication for fronto-orbital expansion in addition to vault reconstruction, whereas significant occipital protrusion was an indication for transverse posterior vault expansion and recession in addition to anterior two-thirds vault reconstruction. Excellent aesthetic results were obtained in all cases regardless of the type of reconstruction performed. However, it is essential that the extent of the deformity be carefully evaluated preoperatively to permit selection of the appropriate technique for reconstruction.

Algorithms↗