Biomedical subjects

Stephen P Beals

Publications and source records attributed to Stephen P Beals.

9 recordsLinked to original sources

PubMed2005

Exposure of midline cranial base without a facial incision through a combined craniofacial-transfacial procedure.

OBJECTIVE: A single-stage combined craniofacial-transfacial approach that exposes the midline cranial base without visible facial incisions is described. METHODS: Between 1992 and 1998, eight patients underwent surgery for five different anterior cranial base pathological findings: four angiofibromas, one mesenchymal chondrosarcoma, one esthesioneuroblastoma, one odontogenic myxoma, and one encephalocele. In all cases, the surgical exposure consisted of a bicoronal scalp incision with a bifrontal craniotomy and fronto-orbitonasal osteotomy, and then a sublabial incision for transmaxillary exposure. RESULTS: Gross total resection was achieved in five cases. The encephalocele was resected with complete reconstruction of the bony defect. Seven patients developed complications, primarily wound infections, cerebrospinal fluid leaks, and anemia. Postoperative Karnofsky Performance Scale scores ranged between 80 and 100 (mean, 92.5). Long-term follow-up information (mean, 56 mo; median, 59.5 mo; range, 5-108 mo) was available for all patients. CONCLUSION: Large anterior cranial base lesions can be resected and excellent cosmetic outcomes can be achieved with a single-stage combined transfacial-craniofacial approach that exposes the entire midline cranial base and requires no facial incisions.

Adolescent↗

PubMed2005

Preserving olfactory function in anterior craniofacial surgery through cribriform plate osteotomy applied in selected patients.

OBJECTIVE: Olfaction is often sacrificed to gain access to the cranial base in anterior craniofacial surgery. We describe the long-term results of olfactory function in patients who underwent anterior craniofacial surgery and a cribriform plate osteotomy to preserve olfaction. METHODS: Between 1992 and 2004, 28 patients underwent 29 cribriform plate osteotomies in an attempt to preserve olfaction during anterior craniofacial surgery performed through modified extended transbasal approaches. Patients' charts and office notes were reviewed retrospectively. Formal olfactory testing was available in 5 patients, but most data were based on patients' subjective reports of olfaction. Olfactory preservation was defined by the subjective ability to detect fumes such as coffee, chocolate, roses, and orange juice regardless of the intensity of the sensation. Follow-up was based on phone calls to patients. RESULTS: Four patients were lost to follow-up and excluded. Therefore, follow-up was available in 24 patients after 25 procedures. On the basis of patients' subjective reports, olfaction was spared in 22 patients after 23 procedures (92%) and was confirmed objectively in the five patients formally tested. After surgery, only two patients were anosmic. CONCLUSION: Olfaction can be preserved in selected patients undergoing anterior craniofacial surgery. At least 1 cm of nasal mucosa should remain attached to the cribriform plate, which can be achieved by including the nasal bone in the osteotomy of the orbital bar. A medial orbital canthopexy is therefore necessary after these procedures.

Adolescent↗

PubMed2005

Comparison of plaster casting with three-dimensional cranial imaging.

OBJECTIVE: The development of a new cranial imaging system to capture a three-dimensional (3D) model of an infant's head has been previously reported. The accuracy of this new system has been independently established. However, before replacing the traditional plaster casting technique, the two methods require a comparison to ensure that the models they produce are equivalent. METHODS: Ten sequential infants were digitized by the 3D imaging system and the plaster casting technique following previously reported protocols. The cast models were also digitized so they could be compared with the digitized images. The two models (3dImage and Cast) were then imported into dimensional analysis software and aligned and registered with well-established registration algorithms. Difference maps that identified the variation between the two surfaces were generated for each pair, and descriptive statistics of these differences were recorded. RESULTS: The mean difference between the cast and the digitized models was 0.052 mm (standard deviation = 0.988), with a root mean square (RMS) difference of 1.028 mm. Two-dimensional slices obtained from the registered 3D surfaces demonstrated excellent agreement between the cranial contours. CONCLUSIONS: In this investigation, the 3D models created by the new imaging system were found to be within 1.0 mm RMS of the models created by the plaster casting technique. Two-dimensional cranial contours demonstrated excellent agreement between the two methods. The results of this investigation confirmed that the new cranial imaging system and the traditional plaster casting technique yield equivalent models.

Algorithms↗

PubMed2005

The radical transbasal approach for resection of anterior and midline skull base lesions.

OBJECT: Craniofacial surgery can be performed to treat midline and anterior skull base lesions by creating a bicoronal scalp incision without the need for an additional transfacial procedure. Originally described as the transbasal approach, several modifications for further exposure of the skull base have been described. The authors present data on the application and outcomes of a modified transbasal approach. The radical transbasal approach consists of a bifrontal craniotomy and a frontoorbitonasal osteotomy. METHODS: Between 1992 and 2002, 41 patients (28 male and 13 female patients with a mean age of 38.3 years [range 7-77 years]) underwent 44 radical transbasal procedures. Twenty-three malignant and 18 benign lesions involving the midline skull base were treated. These cases were reviewed retrospectively. Gross-total resection of 30 lesions was achieved. Seven lesions were resected subtotally and six partially; one lesion was debulked. Complications occurred in 26 (59.1%) of the 44 operations and mostly consisted of cerebrospinal fluid leakage. The surgery-related mortality rate was 6.8% (three patients). Based on their pre- and postoperative Karnofsky Performance Scale scores, 86.4% of patients improved or remained the same. CONCLUSIONS: The radical transbasal approach increases the midline craniofacial corridor by allowing the globes to be safely retracted laterally. It also enhances exposure of the maxillary sinus from above. The morbidity and mortality rates associated with this procedure are high but consistent with the known rates for craniofacial surgery. This approach is best suited for the treatment of anterior skull base tumors that extend into the nasal cavity, orbit, ethmoid sinus, nasopharynx, and upper clivus. The approach may allow resection of tumors involving the maxillary sinus area without the need for an additional transfacial approach.

Adolescent↗

PubMed2004

Form and function in craniofacial deformities.

The interplay of form and function is recognized throughout nature. Whether at the cellular level or visible form, physiological function will not be optimal if not supported by ideal morphology. This principle could not be more true than in the relationship between the human skull and face. The development of ideal skull and facial skeletal form is critical for the function of the brain, vision, airway, mastication, and speech. When craniofacial structure is altered by birth defects, proper functioning is drastically affected. We review the neurocranial basis for normal craniofacial skeletal development and present craniofacial abnormalities that illustrate their deleterious affect on facial function.

Child↗

PubMed2004

Development of a new three-dimensional cranial imaging system.

The development of a new three-dimensional (3D) imaging system designed to obtain a digital image of an infant's cranium is described. This system is intended to replace the manual plaster-casting technique currently used during the process of fabricating cranial remodeling bands. The system uses 18 triangulated digital cameras and the projection of random infrared patterns to capture a 360 degrees image of an infant's cranium instantaneously, including the face and top of the head. Accuracy was calculated by comparing models digitized with this system with the same models digitized with high-precision inspection equipment. Safety was documented under guidelines established by the American Council of Governmental Industrial Hygienists. Images were acquired in 0.008 seconds and processed for viewing in software within 2.5 minutes. Accuracy was calculated to be +/-0.236 mm. Hazard analysis confirmed the system to be safe for direct continuous exposure. The data acquired may be viewed as a point cloud, wire frame, or surface on which a digital photograph (ie, texture) is automatically overlaid. Physical models are created by exporting the digital data to a multiaxis milling machine or stereolithography machine. Quantitative data (linear and surface measurements, curvature, and volumes) can be obtained directly from the digital data. The cranial imaging system is a safe and accurate method of obtaining digital 3D images of an infant's cranium. Along with the obvious clinical and manufacturing benefits, it also has significant potential as a research tool for documenting the natural history and evaluating the treatment of plagiocephaly.

Cephalometry↗

PubMed2003

Posttreatment imaging of the skull base.

Imaging the skull base after surgery can be challenging because anatomic structures may have been destroyed by an underlying process or removed at surgery. Foreign substances may be introduced to fill a void left by tumor resection, for hemostasis, and to repair dural defects. Previous imaging studies must be available for comparison to understand the characteristics of an underlying lesion. By following the progression of a lesion on subsequent imaging studies, the nature of treatment-related changes and residual or recurrent pathology is best realized.

Angiography↗

PubMed2002

Multiple-birth infants at higher risk for development of deformational plagiocephaly: II. is one twin at greater risk?

OBJECTIVE: In part 1 of this investigation, we demonstrated that children of multiple birth pregnancies are at higher risk for development of deformational plagiocephaly. In the current investigation, we explore whether certain prenatal and postnatal risk factors predispose one twin over the other by examining the occurrence and severity of plagiocephaly in both discordant (only 1 affected) and concordant (both affected) twin pairs. METHODS: Throughout 1999, we obtained detailed medical histories on 140 sets of twins who had presented for treatment at 1 of 9 treatment centers across the United States. The study cohort consisted of 46 concordant and 94 discordant twin pairs (a total of 280 study participants). Information about prenatal and postnatal history of each infant was obtained through detailed review of the children's medical records as well as analysis of a patient database maintained on all infants who receive treatment. Follow-up interviews were performed to verify the information recorded and to obtain additional information about the child who had not received treatment (if appropriate) or use of reproductive assistance (fertility drugs, intracytoplasmic sperm injection, etc) that had not been previously recorded. Statistical analyses were performed to assess the effects of prenatal and postnatal risk factors (in utero position, in utero orientation, birth weight, neck involvement, sleeping position) with respect to which infant was affected in the discordant twin pairs and to which infant was more severely affected in the concordant twin pairs. RESULTS: Statistical analyses of both discordant and concordant twin pairs demonstrated that the lower in utero infant was significantly more likely to be affected (chi(2) = 17.391). In addition, the more severely affected infant was significantly more likely to have some form of neck involvement (torticollis, neck tightness; chi(2) = 46.380), as well as have been carried in a vertex position (chi(2) = 7.408). Conversely, neither sleeping position nor gender was found to be associated with development of plagiocephaly. CONCLUSIONS: The results of this investigation strongly support an in utero cause of plagiocephaly and demonstrate that intrauterine positioning may play a prominent role in determining both the occurrence and severity of deformational plagiocephaly in twins. These findings confirm that the lower in utero infant is at increased risk for the development of plagiocephaly, likely resulting from the more restrictive intrauterine environment encountered during the later part of the pregnancy.

Abnormalities, Multiple↗

PubMedDate not supplied

A study of family head shape: environment alters cranial shape.

A change in the type of cranial deformities (plagiocephaly) presenting to certain clinics has occurred. The purpose of this study was to compare infant head shapes against head shapes of their biologic parents to explore the roles of heredity and environment on cranial shape. Standardized family photographs and anthropometric measurements demonstrated that 30% of the infants had cranial widths 2 standard deviations above norm, while 4.6% had widths exceeding 3 standard deviations. Despite a mean age of only 8 months, 11.6% had widths that were already greater than that of 1 parent. These results demonstrate that plagiocephaly has taken on a new configuration, presenting not only with asymmetry, but also with excessive cranial width.

Adult↗