Biomedical subjects

Richard J Langford

Publications and source records attributed to Richard J Langford.

5 recordsLinked to original sources

PubMed2003

Maxillary volume growth in childhood.

Nasomaxillary abnormalities in form, position, and development in children are often prominent features of craniosynostosis, and in particular, craniofacial dysostosis. While attempting to quantitatively assess the volumetric maxillary deficiency in these patients, it became apparent that there was no "normal" reference range for maxillary volumes throughout childhood that could be used for comparison. The aim of this study was to generate a model for measuring maxillary volume and subsequent changes throughout childhood. The technique of segmentation was applied to magnetic resonance images obtained in 55 healthy children (30 boys, 25 girls), aged 1 month to 184 months (15.33 years). Maxillary volumes were plotted against age for boys and girls to create a model for normal maxillary growth during the first 15 years of life. Maxillary volumes were larger in boys at all ages. However, the pattern of maxillary growth in boys and girls was similar and could be divided into three periods, each lasting approximately 5 years. During the first 5 years of life, there is a steady increase in maxillary volume, at the end of which the maxilla has reached 53 percent of the volume recorded at 15 years. There is an accelerated rate of growth between 5 and 11 years, which corresponds to the development and eruption of the permanent dentition. Thereafter, until the age of 15 years, the rate of growth of the maxilla plateaus. Maxillary volume in the first 12 months of life is, on average, 29 cm3 in boys and 25 cm3 in girls. By 15 years of age, it has increased to an average of 73.0 cm3 in boys and 59.4 cm3 in girls (an increase by a factor of 2.5 in boys and 2.4 in girls). The difference between the two sexes is statistically significant for the entire series (boys: mean maxillary volume = 56.55 cm3, SD = 24.61; girls: mean maxillary volume = 40.68, SD = 17.69, p = 0.009, one-way analysis of variance).

Adolescent↗

PubMed2003

Maxillary volume growth in craniosynostosis.

Craniosynostosis, and in particular, craniofacial dysostosis, exhibits abnormalities of the nasomaxillary complex in form, position, and development. The aim of this study was to quantitatively assess the volumetric maxillary abnormality in patients at the time of initial diagnosis of craniosynostosis and to make comparisons with a "normal" reference range for maxillary volumes throughout childhood. The technique of segmentation was applied to preoperative computed tomographic head scans obtained in 31 children (14 boys, 17 girls), between 1 and 34 months of age (mean, 11.06 months), who underwent cranial expansion surgery for craniosynostosis affecting the coronal suture complex. Maxillary volumes were plotted against age for the first 3 years of life and were compared with a healthy population. There was no statistical difference between the two sexes for mean maxillary volume. The mean maxillary volumes for the entire group were statistically smaller than the norm (p = 0.046, linear regression with age as a covariable), but there was no statistical difference among the four different groups of coronal synostosis (unilateral coronal, nonsyndromic bilateral coronal, nonsyndromic complex pansynostosis, syndromic bilateral coronal synostosis) (p = 0.407, one-way analysis of variance). On graphic data analysis, the maxillary volume was smaller than the norm in craniosynostotic children who presented in the first few months of life. However, by 7 months of age in nonsyndromic bilateral coronal synostosis and by 17 months of age in syndromic bilateral coronal synostosis, the maxillary volumes had increased toward the norm. This implies that the effect of the craniosynostotic process on the midface structures is present from birth and parallels the effect on the cranial vault sutures.

Age Factors↗

PubMed2003

Removal of miniplates in maxillofacial surgery: University Hospital Birmingham experience.

PURPOSE: We sought to study the incidence and causes of removal of osteosynthesis miniplates (plates) in oral and maxillofacial surgery in a single unit over a 13-month period and to identify factors associated with plate removal. PATIENTS AND METHODS: We conducted a retrospective study of 172 patients attending the Department of Oral and Maxillofacial Surgery, University Hospital Birmingham, between November 1, 1998, and November 30, 1999, in whom maxillofacial osteosynthesis plates were inserted or removed. Not all patients who had plates removed had them inserted within the same time frame. RESULTS: During a period of 13 months (November 1, 1998, through November 30, 1999), 308 plates were inserted into 153 patients. During the same period, 51 plates were removed from 28 patients, of whom 9 underwent plate insertion and subsequent removal of 25 plates within the time period of the study. Thirty-four (67%) of the plates removed from 20 patients were symptomatic. Infection was the most common cause for removal, occurring in 14 patients (50% of patients who had plates removed) and accounting for 22 plates (43% of plates removed). Symptoms relating to plates necessitating removal occurred in the first year after insertion in 15 patients (53%), accounting for 21 plates. CONCLUSIONS: Our experience with the removal of miniplates is comparable with that of previous studies. Plate-related problems leading to removal are more likely to occur within the first year after insertion.

Adolescent↗

PubMed2002

Tissue changes adjacent to titanium plates in patients.

INTRODUCTION: Titanium miniplates are widely used for osteosynthesis in maxillofacial surgery. Titanium is considered to be well tolerated but the long-term effects of titanium retained within human tissues are unclear. AIMS: This study was designed to evaluate histomorphologically the soft tissues adjacent to titanium maxillofacial miniplates and screws in patients, and to determine the nature of pigmented, particulate debris found in the tissues. MATERIALS: Thirty-five soft tissue specimens were excised from the tissues adjacent to titanium miniplates which had been in situ for between 1 month and 13 years. METHODS: All of the soft tissue specimens were prepared for examination under the light microscope. Four specimens were examined under the scanning electron microscope and the transmission electron microscope. Energy dispersive X-ray analysis (EDX) was used to confirm the elemental composition of the particles under investigation. RESULTS: All of the soft tissues showed fibrosis. Pigmented debris was present in 70% of the specimens and titanium was identified by EDX analysis. The debris was predominantly extra-cellular and was not associated with any inflammatory response or giant cell reaction. Fibroblasts were the predominant cell with small aggregates of lymphocytes and scattered macrophages. CONCLUSION: Titanium is apparently well tolerated for up to 13 years.

Adolescent↗

PubMed2002

Valves in the subsidiary lymph trunks in the neck.

INTRODUCTION: The thoracic duct drains both lymph and chyle into the confluence of the great veins in the root of the neck. The venous termination of the duct is protected from retrograde flow of blood by valves. However, little attention has been focused on the presence or absence of valves in the subsidiary lymph trunks in the neck. AIMS: The aim of this study was to determine whether there are valves in the subsidiary lymphatic system in the neck. MATERIAL AND METHODS: The left side of the neck was explored in ten formalin-fixed cadavers. Subsidiary lymphatic trunks were carefully preserved for stereomicroscopic examination. RESULTS: Eight subsidiary trunks were identified comprising four jugular, two subclavian and two bronchomediastinal trunks. Both subclavian lymph trunks drained directly into a vein. A bicuspid ostial valve was present at the termination of the trunks. The bronchomediastinal and jugular trunks drained into the thoracic duct prior to its venous termination. Valvular structures were identified along the bronchomediastinal trunks and at their termination with the thoracic duct. No valves were identified in the jugular trunks. CONCLUSION: The absence of valves in the jugular lymph trunks is proposed as a possible contributory factor in the creation of chyle leaks following neck dissections.

Humans↗