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Biomedical subjects

J M Vaandrager

Publications and source records attributed to J M Vaandrager.

At least 19 recordsLinked to original sources
PubMed2001

Analgesic efficacy of rectal versus oral acetaminophen in children after major craniofacial surgery.

BACKGROUND: Analgesic acetaminophen (INN, paracetamol) plasma concentrations after major surgery in neonates and infants have not yet been established in the literature. We therefore conducted a study in our intensive care unit. METHODS: Forty children, mean (standard deviation) age, 10.3 (2.3) months, received 20 mg/kg acetaminophen either orally (n = 20) or rectally (n = 20) every 6 hours after a rectal loading dose (40 mg/kg) during elective craniofacial correction. Blood samples were taken 1 hour before and 2 hours after administration of acetaminophen maintenance doses; pain scores were obtained every 3 hours. RESULTS: Acetaminophen plasma concentrations were higher in patients receiving rectal acetaminophen (mean area under the concentration-time curve [AUC], 171.2 mg x h/L) than in patients receiving oral acetaminophen (mean AUC, 111.9 mg x h/L). Pain scores were higher in patients receiving oral acetaminophen. However, after exclusion of the patients who vomited from the group receiving oral acetaminophen, acetaminophen plasma concentrations and pain scores did not differ between the groups. There was no relation between acetaminophen plasma concentrations and pain scores. Although 9 of all 40 patients (22.5%) did not reach the expected analgesic acetaminophen plasma concentrations of 10- to 20 mg/L, <7.5% of the visual analog scale pain scores exceeded 4 cm, which was considered as a cutoff point. CONCLUSION: These are the first data showing that the analgesic acetaminophen plasma concentration after major surgery in this age group does not always reach the 10 to 20 mg/L level. These data also show that, after a rectal loading dose of 40 mg/kg has been given during surgery, the best way of administering acetaminophen after craniofacial surgery is the rectal route.

Acetaminophen↗
PubMed2001

Relationship in hypoplasia between the masticatory muscles and the craniofacial skeleton in hemifacial microsomia, as determined by 3-D CT imaging.

The purpose of this study, based on three-dimensional (3-D) computed tomographic (CT) reconstructions, was to evaluate the relation between underdevelopment of masticatory muscles and hypoplasia of the craniofacial skeleton in hemifacial microsomia (HFM). In 25 patients with HFM and 19 control patients the volumes of the masseter, the temporal, and the medial-pterygoid and lateral-pterygoid muscles were measured on the basis of CT scans, using three-dimensional segmentation and voxel addition. The size and shape of the craniofacial structures were classified, using three-dimensional imaging based on CT scans. Contiguous 1.5-mm computed tomography scans were made with a Philips Tomoscan 350 and processed by a Cemax 1500X 3-D workstation. Using the Pearson product moment correlation coefficient, the Pruzansky/Kaban classification system, the new Craniofacial Deformity Scoring System, Cranial Deformity Scoring System, and Mandibular Deformity Scoring System (MDS) demonstrated correlation coefficients with the "masseter muscle percentage" varying from 0.71 to 0.81 (P < 0.05), with the medial pterygoid muscle percentage correlation coefficient varying from 0.43 to 0.56 (P < 0.05), with the lateral pterygoid muscle percentage correlation coefficient varying from 0.55 to 0.61 (P < 0.05), and with the temporal muscle percentage correlation coefficient varying from 0.67 to 0.84 (P < 0.05). The normal right/left difference in volume of the masticatory muscles of the control patients, calculated as a percentage of the total, demonstrated small differences of 3.4% to 4.8%. Bony malformations are associated with underdevelopment of the masseter and the temporal muscles, and demonstrate a tendency toward a clear relationship. The degree of muscular underdevelopment of the different muscles of mastication in one patient could vary widely. The normal right/left difference of the masticatory muscles of the control patients is minimal. The volume of the masticatory muscles of the non-affected side does not demonstrate a compensatory effect in patients with HFM.

Analysis of Variance↗
PubMed2001

CT-based size and shape determination of the craniofacial skeleton: a new scoring system to assess bony deformities in hemifacial microsomia.

The purpose of this study was to design a better craniofacial classification system for bony deformities in patients with hemifacial microsomia than the existing ones. It was meant to incorporate the deformity of the craniofacial skeleton other than that of the mandible. The "Mandibular Deformity Scoring" System (MDS), the "Cranial Deformity Scoring" System (CDS), the the "Craniofacial Deformity Scoring" System (CFDS) are three newly developed classification systems, which are based on three-dimensional computed tomography (3-D CT) reconstructions. The size and shape of the craniofacial structures of 34 children, 25 with hemifacial microsomia and 9 with minimal dysplasia or trauma, were determined from CT scans, using 3-D image segmentation and rendering. Contiguous 1.5-mm CT scans were made using a Philips Tomoscan 350 and were processed using a Cemax 1500X 3-D workstation. The precision of the 3-D imaging was assessed by repeated determinations carried out by two observers (intra- and interreliability). Accuracy of the bone determination technique was assessed by comparing the interpretations of the craniofacial skeleton by 3-D CT reconstructions of laser-stereolithographic 3-D models. Correlations of the Pruzansky/Kaban classification system and the newly developed classification systems were demonstrated by the use of the Pearson product moment correlation coefficients. The new CFDS (= CDS + MDS) provides an adequate basis for assessment of bony structures using three-dimensional imaging and demonstrates a high correlation with the known Pruzansky/Kaban classification system. This new scoring system can handle the wide variety of individual variation of the deformity seen in patients with hemifacial microsomia better than the existing scoring systems.

Case-Control Studies↗
PubMed2001

The nasal dorsum as a donor site for the correction of alar, lobular, and columellar malformations.

There is a wide variety of donor sites available for minor nasal reconstructions involving alar, lobular, and columellar defects. Unfortunately, the problems all these sites have in common are that the color match may be unsatisfactory or that the end result may be marred by conspicuous scarring. If nasal-skin resources could be fully exploited, the elimination of these two important problems could become an obtainable goal. This article discusses the potential of the nasal dorsum as a donor site and describes methods that were used to try to achieve this goal. Skin redistribution, skin expansion, and skin distraction methods were used in 28 patients with alar (n = 13), lobular (n = 8), and columellar (n = 7) malformations and who had been followed up since the early 1980s.

Adolescent↗
PubMed2000

[Fifty years of plastic surgery in the Netherlands. VIII. Craniofacial surgery].

Craniofacial surgery has developed its own identity in the last 3 decades. The Frenchman Tessier can be seen as the founding father. His concept of intracranial correction of craniofacial malformations is still valid today. There have been many new developments such as distraction osteogenesis and biodegradable miniplate fixation. Microvascular surgery and vascularised calvarial bone grafts help to obtain more predictable results. Three-dimensional CT imaging techniques and modelling result in better surgical planning and help to understand the underlying pathology. Biomolecular knowledge of gene mutations leads to better understanding of the clinical diagnosis. The future will bring minimalisation of surgery and more therapy focused on biomolecular science. The psychosocial welfare of the patient will play a central role in the multidisciplinary team treatment.

Craniofacial Abnormalities↗
PubMed1999

Symmetry and morbidity assessment of unilateral complete cleft lip nose corrected with or without primary nasal correction.

OBJECTIVE: Unilateral complete cleft lip patients treated with or without a primary nasal correction at the time of cleft lip repair were compared to evaluate the relevance of early surgical correction of the nose by using two assessments: nasal symmetry and morbidity. DESIGN, SETTING, PATIENTS: The no nasal correction group (NNC, n = 19) was operated by surgeon A using the Millard technique. The primary nasal correction group (PNC, n = 9) was operated by surgeon B combining the modified Millard technique with a columellar lift and alar mobilization. Symmetry was assessed on two sets of standardized photographs at 9 years of age using a computer-assisted analysis. Both cleft groups were compared with normal controls (NC, n = 20). The computer method included area and angular measurements. Morbidity was assessed by the number of procedures on the vermilion, the lip, and/ or nose for revisional surgery up to the age of 9 (NNC, n = 26; PNC, n = 12). RESULTS: No significant differences in symmetry were found between the NNC and PNC groups regarding the area and angular measurements. With regard to the area measurements, both cleft groups produced a significant asymmetry when compared to the NC group. Concerning the angular measurements, however, the NNC group differed significantly from the NC group, whereas such a difference could not be noted between the PNC group and NC group. With respect to morbidity, no revisional procedures were performed in the PNC group. The number of revisional procedures in the NNC group was 16 in 10 patients. CONCLUSION: Results are presented that favor, up to the age of 9 years, a primary nasal correction at the time of cleft lip repair.

Child↗
PubMed1998

Three-dimensional imaging of congenital disorders involving the orbit.

Three-dimensional imaging of the orbit and its adnexa provides an excellent topographic visualization of the deformity or tumor extent. This helps comprehension, communication, education, and documentation in the process of treating the patient. This article briefly describes the technique of three-dimensional imaging and classifies congenital orbital deformities which are extensively illustrated with relevant case material.

Communication↗
PubMed1998

Pfeiffer's syndrome resulting from an S351C mutation in the fibroblast growth factor receptor-2 gene.

For four of the most well-known craniosynostosis syndromes--Apert's, Crouzon's, Pfeiffer's, and Jackson-Weiss' syndromes--mutations in the fibroblast growth factor receptors (FGFRs) have been described. These substitutions arise mainly in the FGFR-2 gene and to a much lesser degree in the FGFR-1 and FGFR-3 genes. We present a patient with an apparently sporadic type of Pfeiffer's syndrome, exhibiting nearly all associated features of this syndrome. A mutation in the FGFR-2 gene was found, namely serine351-cysteine. This mutation has been reported in only one patient so far, whose phenotype could match both Crouzon's and Pfeiffer's syndromes.

Acrocephalosyndactylia↗
PubMed1997

Apoptotic cell death during normal embryogenesis of the coronal suture: early detection of apoptosis in mice using annexin V.

Regulation of programmed cell death (apoptosis) is crucial for normal development and growth, both prenatally and postnatally. If its role during normal embryogenesis of a given structure is established, a number of related congenital disorders can be explained by a (local) deregulation of apoptosis. In this study, apoptotic cell death patterns during normal development of the murine coronal suture were investigated. Detection of apoptotic cells was undertaken by labeling with Annexin V. Results showed apoptosis occurring at the same time and place as suture initiation. Apoptotic cells are located along the entire established part of the suture and its developing part. Because apoptosis is shown to be highly associated with sutural genesis, the theory of craniosynostosis being the equivalent of deregulation at this locus seems in line with these findings.

Affinity Labels↗
PubMed1996

The role of bone centers in the pathogenesis of craniosynostosis: an embryologic approach using CT measurements in isolated craniosynostosis and Apert and Crouzon syndromes.

This paper describes the role of the displacement of bone centers, i.e., the tubers, in the pathogenesis of craniosynostosis. This displacement was studied in 54 patients with isolated or syndromic craniosynostosis in the form of CT scans as well as in two dry neonate skulls with Apert syndrome. For comparison, 49 fetal and 8 normal infant dry skulls were studied. Our investigation was restricted to the coronal and metopic sutures. The results showed a significantly more occipital localization of the frontal bone center and a more frontal localization of the parietal bone center at the side of a synostotic coronal suture in the isolated form as well as in Apert syndrome. In contrast, this was not the case in Crouzon syndrome, thus showing that these two syndromes have a different pathogenesis. For trigonocephaly, a more anteromedial localization of the frontal bone centers was found.

Acrocephalosyndactylia↗
PubMed1995

Plagiocephaly--new classification and clinical study of a series of 100 patients.

The term of 'plagiocephaly' coined by Virchow in 1851, that literally means 'cranial asymmetry' has been applied to dysmorhic skulls that look similar but which sometimes have a different etiology. The authors report a new clinical classification of plagiocephaly in order to simplify the categorization of this disease. A series of 100 patients with plagiocephaly were observed and treated. A clinical investigation of these cases, some considerations about the techniques used, the analysis of the results and a long-term follow-up complete the study reported.

Bone Transplantation↗
PubMed1995

Dehiscence of the jugular bulb in Crouzon's disease.

Patients with Crouzon's disease have a distorted nasopharynx, which frequently leads to retained middle ear secretions and necessitates myringotomy. A review of the computed tomographic (CT) scans of 21 ears in 11 patients with Crouzon's disease found that 12 jugular bulbs were protruding or dehiscent. The relationship between the jugular bulb and the middle ear space was normal bilaterally in only 2 of the 11 patients. Consequently, patients with Crouzon's disease are at risk for inadvertent puncture of the jugular bulb during myringotomy. CT scans obtained prior to myringotomy can be helpful in detecting dehiscent or protruding jugular bulbs.

Adolescent↗
PubMed1995

Treacher Collins syndrome: early surgical treatment of orbitomalar malformations.

In the past various materials have been used for the correction of the malar bone defect, such as cartilage, dermis fat, silicone, autograft, homograft, xenograft, and free bone transplantation. The disadvantages of inorganic implants are well known: dislocation, extrusion, and capsular contraction. The bony autograft has no growth potential, and children may need several complementary corrections. None of these procedures is totally satisfactory. To solve these problems malar reconstruction is performed with the help of a temporal bone flap. Two varieties of these flaps have been described: one anteriorly with a muscular pedicle vascularized by the deep temporal artery and one posteriorly with a galeal pedicle vascularized by the superficial temporal artery. The main advantage of an osteomuscular flap is the survival of bone once it has been transferred. The second advantage is related to the osteogenic potential of the cambium layer of the periosteum, which may prove to be an ongoing concern. Our series of patients includes 20 children. Correction of the eyelid coloboma was obtained by transposition and advancement of a superior palpebral flap.

Adolescent↗
PubMed1994

Clinical evaluation of techniques used in the surgical treatment of progressive hemifacial atrophy.

We critically review 13 patients with progressive hemifacial atrophy treated with three basic surgical procedures (free flap transplantation, alloplastic implants, micro-fat injections 'lipofilling') and further ancillary techniques. In spite of the satisfactory results achieved with the procedures, with the exception of alloplasts, we feel that lipofilling may be considered an interesting solution for soft tissue augmentation of the face especially for moderate adipose defects, due to its repeatability, no donor site morbidity, no complications at the recipient site such as lesions resulting from dissection, bleeding, necrosis, etc. This technique can be performed in a day-hospital with short surgery time, at low cost and without a highly skilled team. For severe grades of adipose atrophy, because of the low blood supply to these tissues which interferes with take of any type of autograft, we think that free flaps actually represent one of the best solutions for soft tissue augmentation.

Adipose Tissue↗
PubMed1994

Progressive hemifacial atrophy in a patient with lupus erythematosus.

This is a single case report describing a young woman with progressive facial atrophy that began at age 15. After she underwent commissuroplasty and collagen injection at age 29, her symptoms continued to progress, and she was ultimately shown to have serologic evidence of systemic lupus. She had a "remission of symptoms" after commencement of medical treatment (chloroquine and topical steroids) for her lupus. The association of progressive hemifacial atrophy and lupus is not new. This case and other cases associated with different autoimmune diseases suggest an autoimmune collagen-vascular origin for some cases of progressive facial atrophy. Furthermore, there is a need to modify the surgical approach in light of concurrent disease.

Adult↗
PubMed1994

[Scaphocephaly. Its clinical study and surgical treatment].

The authors report a clinical study in 51 patients with scaphocephaly. Since 1986 the mathematical patterns of projection geometry have been applied to the reshaping of the skull in the early surgical correction of scaphocephaly. The mathematical and geometric principles are discussed and the surgical technique utilized is illustrated. Results are presented. The authors, encouraged by the very satisfactory results obtained, suggested the application of the method for the reshaping of the skull in other craniofacial malformations.

Craniosynostoses↗