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Dive into the research topics where Piet F. Dijkstra is active.

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Featured researches published by Piet F. Dijkstra.


American Journal of Medical Genetics | 1998

Congenital anomalies in the teratological collection of museum Vrolik in Amsterdam, the Netherlands. II: skeletal dysplasias

Roelof-Jan Oostra; Bob Baljet; Piet F. Dijkstra; Raoul C. M. Hennekam

The Museum Vrolik collection of the Department of Anatomy and Embryology of the University of Amsterdam, founded by Gerardus Vrolik (1775-1859) and his son Willem Vrolik (1801-1863), consists of more than five thousand specimens of human and animal anatomy, embryology, pathology, and congenital anomalies. Recently, the collection of congenital anomalies was recatalogued and redescribed according to contempory syndromological views. The original descriptions, as far as preserved, were compared with the clinical and radiographical findings. In 18 specimens the following skeletal dysplasias were diagnosed: achondrogenesis, achondroplasia, Blomstrand chondrodysplasia, Majewski syndrome, osteodysplastic primordial dwarfism, osteogenesis imperfecta type I, osteogenesis imperfecta type II, and thanatophoric dysplasia with and without cloverleaf skull. Radiography did not yield a diagnosis in 4 specimens. The use of additional diagnostical techniques, such as MRI and CT scanning and fluorescence in situ hybridization in these specimens, is currently being investigated.


European Journal of Nuclear Medicine and Molecular Imaging | 1993

Significance of a hot spot on the bone scan after carpal injury--evaluation by computed tomography.

Monique M. C. Tiel-van Buul; Edwin J. R. van Beek; Piet F. Dijkstra; Ad J. Bakker; Tom H. Broekhuizen; Eric A. van Royen

The use of bone scintigraphy in patients with negative radiographs after carpal injury is widely advocated. However, focally increased activity on the bone scan in the scaphoid or other carpal bones cannot always be radiologically confirmed as a fracture. To confirm scintigraphically suspected carpal fractures, computed tomography (CT) of the wrist was performed in patients with clinically suspected scaphoid fracture and initially negative radiographs. All patients underwent plain radiography, bone scintigraphy and CT. The combination of plain radiographs and CT, as judged by a panel of experienced observers, was used as the reference standard. In 18 patients, 21 out of 22 carpal hot spots on bone scintigraphy could be radiologically confirmed as a fracture. The diagnosis was missed by CT scan in three patients with proven fractures on plain radiographs. We conclude that, in patients with negative initial radiographs following carpal injury, a positive bone scan must be interpreted as a fracture.


American Journal of Obstetrics and Gynecology | 1988

Prenatal ultrasonographic diagnosis of osteogenesis imperfecta

Jozien T. J. Brons; Hans J. van der Harten; Juri W. Wladimiroff; Herman P. van Geijn; Piet F. Dijkstra; Niek Exalto; A. Reuss; M. F. Niermeijer; Chris J. L. M. Meijer; N.F.T. Arts

Between 1982 and 1986, osteogenesis imperfecta was diagnosed by ultrasound in seven fetuses. The known heterogeneity of osteogenesis imperfecta was confirmed by the prenatal ultrasonographic findings. Dependent on the type of osteogenesis imperfecta, the appearance of the limbs varied from severely shortened and broad, with very low echogeneity and absent acoustic shadow (type IIA), to only moderately shortened and thin, with almost normal echogeneity and acoustic shadow but clearly visible fractures causing angulation of the bone (types IIC and III). Ultrasonography offers the possibility to detect or exclude the lethal and severe forms of osteogenesis imperfecta early (type IIA) or halfway (types IIB, IIC, and III) through the second trimester. Prenatal diagnosis of the disease allows the option of elective abortion or may prevent unnecessary obstetric intervention.


Journal of Medical Genetics | 1995

General overgrowth in the fragile X syndrome: variability in the phenotypic expression of the FMR1 gene mutation

Bert B.A. de Vries; Hazel Robinson; Irene Stolte-Dijkstra; Cecil V Tjon Pian Gi; Piet F. Dijkstra; Jaap van Doorn; Dicky Halley; Ben A. Oostra; Gillian Turner; M. F. Niermeijer

The fragile X syndrome, which often presents in childhood with overgrowth, may in some cases show some diagnostic overlap with classical Sotos syndrome. We describe four fragile X patients with general overgrowth, all of whom are from families with other affected relatives who show the classic Martin-Bell phenotype. Molecular studies of the FMR1 gene in all cases showed the typical full mutation as seen in males affected by the fragile X syndrome. Endocrine studies were unremarkable, except in one case where there were raised levels of insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) These cases illustrate the clinical variability of the fragile X syndrome and the necessity of performing analysis of the FMR1 gene in mentally retarded patients presenting with general overgrowth.


American Journal of Medical Genetics | 1998

Congenital anomalies in the teratological collection of museum Vrolik in Amsterdam, the Netherlands. I: syndromes with multiple congenital anomalies

Roelof-Jan Oostra; Bob Baljet; Piet F. Dijkstra; Raoul C. M. Hennekam

The Museum Vrolik collection of the Department of Anatomy and Embryology of the University of Amsterdam, founded by Gerardus Vrolik (1775-1859) and his son Willem Vrolik (1801-1863), consists of more than 5,000 thousand specimens of human and animal anatomy, embryology, pathology, and congenital anomalies. Recently, the collection of congenital anomalies was recatalogued and redescribed according to contempory syndromological views. The original descriptions, as far as preserved, were compared with the clinical and radiographical findings. In 13 specimens the following multiple congenital anomalies (MCA) syndromes were diagnosed: acrofacial dysostosis, Apert syndrome, Brachmann-De Lange syndrome, ichthyosis congenita gravis, Jarcho-Levin syndrome, Meckel syndrome, oro-facio-digital syndrome type IV, Roberts syndrome, Smith-Lemli-Opitz syndrome, Treacher Collins syndrome, and trisomy 13. It appeared that the founders of the museum studied and described several of these syndromes many years before they became established as such. In some specimens a reliable diagnosis is still pending. The use of additional diagnostical techniques, such as MRI, CT scanning, and fluorescence in situ hybridization, in these specimens is currently being investigated.


Pediatric Radiology | 1990

The prenatal development of the normal human skeleton: A combined ultrasonographic and post-mortem radiographic study

H. J. van der Harten; Jozien T. J. Brons; N. W. Schipper; Piet F. Dijkstra; Chris J. L. M. Meijer; H.P. van Geijn

Post-mortem radiography of fetuses with skeletal dysplasia is essential for diagnostic classification. Interpretation of the radiographs should be based on the knowledge of morphology and dimensions of the normal skeleton in all stages of development. A retrospective post-mortem radiographic study is presented with measurements of the lengths of the long bones and thoracic and lumbar spine. The study included 69 fetuses and neonates with a normal skeleton, whose gestational age ranged from 13–42 weeks and who died perinatally or lived for less than one week. The measurements of the long bones were plotted on growth curves obtained from a prospective longitudinal ultrasonographic investigation of another group of 63 normal fetuses from 12–40 weeks of gestation. Thoracic and lumbar spine measurements by ultrasonography were not available. The radiographic data of thoracic and lumbar spine were, therefore, compared to radiographic studies from the literature. No disagreement with these studies was found. It can be concluded that measurements of bones from standardized post-morten radiographs in cases of questionable gestational age or defects of bone development can be compared with ultrasonographic measurements. To illustrate the usefulness of the graphs, 13 fetuses with various types of skeletal dysplasia were evaluated retrospectively.


Fetal and Pediatric Pathology | 1988

Achondrogenesis…Hypochondrogenesis: the Spectrum of Chondrogenesis Imperfecta a Radiological, Ultrasonographic, and Histopathologic Study of 23 Cases

Hans J. van der Hartet; Jozien T. J. Brons; Piet F. Dijkstra; Martinus F. Niermeyer; Chris J. L. M. Meijer; Herman P. van Giejn; N.F.T. Arts

In the classification of lethal osteochondrodysplasias, achondrogenesis and hypochondrogenesis have recently received special attention. We describe 23 cases representing the different subtypes. Within the classical type I (Parenti-Fraccaro) two distinct disorders can be recognized: type IA (Houston-Harris) and type IB (Fraccaro). The classical type II (Langer-Saldino) and hypochondrogenesis represent phenotypic variants of one disorder in which type II is the most severe form and hypochondrogenesis the mildest form, while transitional forms exist. It is likely that a basic defect in cellular function of the chondrocyte results in a deficient cartilage matrix and in disorganized enchondral ossification.


American Journal of Medical Genetics | 1999

A 100‐year‐old anatomical specimen presenting with boomerang‐like skeletal dysplasia: Diagnostic strategies and outcome

Roelof-Jan Oostra; Piet F. Dijkstra; Bob Baljet; Ben W. J. M. Verbeeten; Raoul C. M. Hennekam

The Museum Vrolik collection of human anatomy comprises 360 recently redescribed specimens with congenital anomalies. The specimen described here dated from 1881 and presented with a general embryonic appearance, disproportionate short stature, brachycephaly, widened cranial sutures, hypertelorism, microphthalmia, bilateral cleft lip and palate, micrognathia, short and curved limbs, polysyndactyly, and abnormal female genitalia. Conventional radiography was hampered by decalcification of the skeleton, due to acidification of the preservation fluid. The use of additional imaging techniques, i.e., mammography, computerized tomography with three-dimensional reconstruction, and magnetic resonance imaging eventually led us to conclude that the condition of our specimen was similar to Piepkorn type skeletal dysplasia, boomerang dysplasia, and a condition described by Carpenter and Hunter [1982: J Med Genet 19:311-315], though none of these diagnoses seemed fully applicable.


Investigative Radiology | 1997

THE VALUE OF ADDITIONAL CARPAL BOX RADIOGRAPHS IN SUSPECTED SCAPHOID FRACTURE

Linda Roolker; M.M.C. Tiel-van Buul; P.M.M. Bossuyt; Piet F. Dijkstra; J.J.M. van Grieken; A. H. Broekhuizen

RATIONALE AND OBJECTIVES Carpal Box (CB) radiographs, transverse and longitudinal, produce elongated and magnified views of the carpus. These radiographs can be used after carpal injury, in addition to conventional scaphoid x-rays. In this study, the use of CB radiographs was evaluated in patients with possible scaphoid fracture. METHODS Seventy-one consecutive patients who presented at the First Aid department from May 1994 to May 1995 were included. All patients were examined for scaphoid fracture after a fall on the out-stretched hand. If a scaphoid fracture was seen on the scaphoid x-rays, patients were immobilized. If the x-rays remained negative or dubious for fracture, additional transverse and longitudinal CB radiographs were obtained. If CB radiographs remained negative or inconclusive, patients were referred for three-phase bone scintigraphy. The results of independent and masked judgment by three different observers were used for an inter- and intraobserver analysis. RESULTS Twenty of 71 patients initially showed a scaphoid fracture on the conventional scaphoid x-rays, 41 were negative, and 10 inconclusive. All 41 negative patients remained negative on CB radiograph; however, the bone scintigraphy was positive for scaphoid fracture in 11 patients and in 9 patients a hot spot elsewhere in the carpus was found. Of the 10 patients with inconclusive x-rays, 2 showed a clear fracture of the scaphoid on CB radiograph, 5 were negative, and 3 remained inconclusive. The agreement between observers, calculated in kappa values, was highest in CB radiographs. CONCLUSIONS In the diagnosis of scaphoid fracture, Carpal Box radiography is of limited value in patients with clinically suspected scaphoid fracture. In two of 10 patients with initial dubious scaphoid x-ray, bone scintigraphy can be avoided. Furthermore, the reliability of the interpretation of the radiographs is increased by additional Carpal Box radiography.


Fetal and Pediatric Pathology | 1988

Perinatal Lethal Osteogenesis Imperfecta: Radiologic and Pathologic Evaluation of Seven Prenatally Diagnosed Cases

Hans J. van der Harten; Jozien T. J. Brons; Piet F. Dijkstra; Chris J. L. M. Meijer; Herman P. van Geijn; N.F.T. Arts; M. F. Niermeijer

The radiologic and pathologic characteristics of 7 cases of lethal osteogenesis imperfecta (OI), diagnosed prenatally by ultrasound in the 15th to 34th week, are described. They include four variants of the Sillence classification: types IIA, IIB, IIC, and type III. The radiologic criteria that differentiate these types of OI are described. The histopathology of the bones differed only slightly in types IIA, IIB, and III; OI type IIC, however, differed markedly from the other types.

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Bob Baljet

University of Amsterdam

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Ben A. C. Dijkmans

VU University Medical Center

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M. F. Niermeijer

Erasmus University Rotterdam

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N.F.T. Arts

VU University Amsterdam

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