Willem J R van Ouwerkerk

VU University Medical Center, Amsterdamo, North Holland, Netherlands

Are you Willem J R van Ouwerkerk?

Claim your profile

Publications (33)51.11 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The purpose of this study was to review the epidemiology and the clinical, radiological, pathological, and follow-up data of all surgically treated pediatric meningiomas during the last 35 years in The Netherlands. Patients were identified in the Pathological and Anatomical Nationwide Computerized Archive database, the nationwide network and registry of histopathology and cytopathology in The Netherlands. Pediatric patients of 18 years or younger at first operation in 1974-2009 with the diagnosis meningioma were included. Clinical records, follow-up data, radiological findings, operative reports, and pathological examinations were reviewed. In total, 72 patients (39 boys) were identified. The incidence of operated meningiomas in the Dutch pediatric population is 1:1,767,715 children per year. Median age at diagnosis was 13 years (range 0-18 years). Raised intracranial pressure and seizures were the most frequent signs at presentation. Thirteen (18 %) patients had neurofibromatosis type 2 (NF2). Fifty-three (74 %) patients had a meningioma World Health Organization grade I. Total resection was achieved in 35 of 64 patients. Fifteen patients received radiotherapy postoperatively. Mean follow-up was 4.8 years (range 0-27.8 years). Three patients died as a direct result of their meningioma within 3 years. Four patients with NF2 died as a result of multiple tumors. Nineteen patients had disease progression, requiring additional treatment. Meningiomas are extremely rare in the pediatric population; 25 % of all described meningiomas show biological aggressive behavior in terms of disease progression, requiring additional treatment. The 5-year survival is 83.9 %, suggesting that the biological behavior of pediatric menigiomas is more aggressive than that of its adult counterparts.
    Child s Nervous System 04/2012; 28(7):1009-15. · 1.24 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Intrathecal baclofen (ITB) treatment is frequently used for individuals with severe, but non-progressive, spasticity refractory to oral treatment. However, experiences with ITB in patients with progressive neurological disorders of childhood causing spasticity are limited. To investigate whether ITB is an option in patients with progressive neurological disorders causing spasticity in childhood. A systematic literature search in Embase, Pubmed and the Cochrane Library was performed. We identified six eligible studies considering patients with progressive neurological disease in childhood and receiving ITB treatment. The studies included a total of seven paediatric patients and four adult patients. Improvement was reported in spasticity, spasms, pain, gait, activities of daily life and providing care. High satisfaction is described. ITB has beneficial effects in paediatric patients with progressive neurological disease. However, the level of evidence is limited due to the small number of available studies and due to the poor quality of these studies.
    European journal of paediatric neurology: EJPN: official journal of the European Paediatric Neurology Society 10/2011; 16(3):279-84. · 2.01 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Children with an obstetric brachial plexus injury (OBPI) can experience problems in the performance of meaningful activities such as writing, bimanual activities, and participation in sports and leisure activities. To quantify the everyday functioning and participation of 7-8 year-old children with an OBPI, with special emphasis on writing, and to investigate associated characteristics. Parents of children with an OBPI were sent a self-report questionnaire regarding the school performance, writing abilities, bimanual hand use, and participation in sports and leisure activities of their child, assessed with the Vineland Adaptive Behavior Scales (VABS sub-scale writing), the ABILHAND-kids, and the Children's Assessment of Participation and Enjoyment (CAPE). Furthermore, questions were asked about socio-demographic variables, medical history, pain, and the use of assistive devices. Fifty three questionnaires were filled in (response 61%). According to the parents, 66% of their children were almost completely recovered, and 58% had a near normal arm function. Most of the children preferred to use their non-involved hand. More than 45% of the children complained about pain, and 39.6% had difficulties with writing, which resulted in a mean developmental delay of 8 months on the VABS sub-scale. Children with writing problems significantly more often had neurosurgery, were living with a single parent, more often received assistance at school, and had a significantly lower ABILHAND-kids score, compared to children with no writing problems. Large percentages of 7-8 year-old children with an OBPI experience difficulties with writing and have musculoskeletal pain. Restrictions in participation were less pronounced.
    European journal of paediatric neurology: EJPN: official journal of the European Paediatric Neurology Society 07/2011; 15(4):345-52. · 2.01 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Treatment options for dystonic cerebral palsy (CP) are limited. Our aims were to determine whether intrathecal baclofen (ITB) improves daily care, decreases dystonia and decreases pain in patients with dystonic CP. Patients received randomized blinded treatment with ITB or placebo. Scores on problems of daily care were recorded and dystonia, pain and comfort were assessed. Four patients (three males, average age 12 years 6 months) were included (all Gross Motor Function Classification System level V). During the trial period problem scores and dystonia scores decreased in all four patients. In this pilot study we report positive functional effects of ITB trial treatment in four patients with dystonic CP. A randomized trial with a larger cohort is needed to verify these results.
    European journal of paediatric neurology: EJPN: official journal of the European Paediatric Neurology Society 05/2011; 15(6):539-43. · 2.01 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The primary aim of this prospective cohort study was to evaluate the short-term (1 year) and long-term (mean 6 years) effects of selective dorsal rhizotomy (SDR) on gross motor function and spasticity in ambulatory children with spastic diplegia. Secondary aims were to investigate side effects, additional treatment during follow-up (botulinum toxin type A injections or orthopedic surgery), and parental satisfaction. Thirty-three children who had undergone SDR at a mean age of 6 years and 7 months (± 2 years) were included. There were 7 children at Gross Motor Function Classification System (GMFCS) Level I, 7 at Level II, and 19 at Level III. Gross motor function was assessed with the Gross Motor Function Measure-66 (GMFM-66). Spasticity was measured according to a modified Tardieu scale. Side effects, additional treatment, and parental satisfaction were recorded using a parental questionnaire and medical records. At 1-year follow-up, mean GMFM-66 scores improved significantly by 4.3 ± 4.1 points. Children at GMFCS Levels I and II showed significantly more improvement (7.2 points) on the GMFM-66 compared with children at GMFCS Level III (2.9 points). On long-term follow-up (mean 6 years ± 22 months), mean GMFM-66 scores improved significantly by 6.5 ± 5.9 points, without a difference between children at GMFCS Levels I and II and Level III. No relapse of spasticity was noted. Ten children (30%) needed orthopedic surgery and 13 children (39%) received botulinum toxin type A treatment after SDR. Twenty (91%) of the 22 parents who answered the questionnaire at long-term follow-up believed that their child's functioning had improved after SDR. Selective dorsal rhizotomy resulted in short- and long-term improvements in gross motor function, without relapse of spasticity. However, the majority of the children still needed additional surgery or botulinum toxin A treatment.
    Journal of Neurosurgery Pediatrics 05/2011; 7(5):557-62. · 1.63 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Shoulder deformities in children with a birth brachial plexus injury (BBPI) are caused by muscle imbalances; however, the underlying mechanisms are unclear. The aim of this study was to assess the early interactions between shoulder muscles and shoulder joint development. In a retrospective magnetic resonance imaging (MRI) study of 36 infants (21 males, 15 females) younger than 12 months (mean 4.8 mo) with unilateral BBPI, volumes and thicknesses of standardized segments of the infraspinatus, subscapularis, and deltoid muscles were measured in both shoulders and expressed as ratios of pathological/unaffected side. The relation between muscle ratios and humeral head subluxation, passive external rotation, glenoid version, and deformity was analysed. Compared with the unaffected side, the muscles of the affected side were of significantly smaller volume and thickness. The subscapularis was the most severely affected muscle, its volume being only 64% (SD 21%) and its thickness only 79% (SD 23%) of the corresponding values on the unaffected side (p < 0.001). Severe subluxation was predicted by the combination of low infraspinatus and subscapularis volume ratios (r(2) = 0.223; p = 0.014), but not by muscle thickness ratios. Subluxation was related to passive external rotation (p < 0.05), glenoid version (p < 0.01), and deformity (p < 0.01). In infants with BBPI, muscle size is decreased during in the first months of life by both atrophy and, possibly, by a reduction in the number of sarcomeres in series. These effects are strongly related to shoulder joint subluxation.
    Developmental Medicine & Child Neurology 02/2011; 53(2):173-8. · 2.68 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The primary aim of this study is to perform an internal quality control of pediatric brain tumor surgery in the neurosurgical department of the VU University Medical Center Amsterdam (The Netherlands). Secondly, this study aims to contribute to the accumulating data concerning outcome in pediatric neurosurgery, in order to establish institutional practice benchmarks. We report the surgical mortality and morbidity of 121 patients (0-18 years) surgically treated for a brain tumor from January 1999 to August 2007. Patients, in whom only a brain tumor biopsy was performed, were excluded. Mean age at first surgery was 8.2 years. Of the 121 patients, 14 had a second surgery, and two underwent a third surgery (for a total of 137 operations). Of all 121 primary surgeries, 66% were total resections, 26% subtotal resections, and 8% partial resections. The overall surgical morbidity rate in this study was 69% after first surgery, 50% after second surgery, and one out of two after third surgery. These overall morbidity rates are comparable to other published mixed case series. The surgical mortality rate was 0.8%; this is comparable to the lowest rates reported for high-volume neurosurgical centers. We encourage other neurosurgical centers to collect, analyze, and publish their data. These data can then serve as a basis for comparison with other pediatric neurosurgical centers and will eventually lead to an improvement of pediatric neurosurgical practice and patient care.
    Child s Nervous System 03/2010; 26(11):1583-92. · 1.24 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To identify MRI characteristics that may predict the functional effect of selective dorsal rhizotomy (SDR) in children with bilateral spastic paresis. We performed SDR in a group of 36 patients. The gross motor functioning measure-66 (GMFM-66) was applied before and after SDR. Available cerebral MRIs were retrospectively classified into three diagnostic groups: periventricular leucomalacia (PVL; n = 10), hydrocephalus (n = 2), and normal (n = 6). In patients with PVL, we scored the severity of the MR abnormalities. We compared the changes in the GMFM-66 after SDR in the diagnostic groups. In patients with PVL, we correlated the severity of the MR abnormalities with the changes in the GMFM-66. The mean follow-up period was 5 years and 4 months (range, 1 year and 1 month to 9 years). The best improvement in gross motor function was observed in patients with normal MRI, and the slightest improvement was observed in patients with hydrocephalus. The severity of the PVL did correlate with the GMFM-66 score before SDR but not with the functional effect of SDR. We conclude that with respect to gross motor skills, the improvements after SDR are good in patients with no MRI abnormalities. In the patients with hydrocephalus, the improvements after SDR were insignificant. In patients with PVL, the improvements were intermediate and did not correlate with the degree of PVL.
    Child s Nervous System 10/2009; 26(2):191-8. · 1.24 Impact Factor
  • Margje Spijker, Rob L M Strijers, Willem J R van Ouwerkerk, Jules G Becher
    [Show abstract] [Hide abstract]
    ABSTRACT: Selective dorsal rhizotomy is an effective treatment for spasticity in children with cerebral palsy who have a spastic motor disorder. It is hypothesized that muscle shortening is related to spasticity; the lack of stretch of a muscle is thought to be the cause of muscle shortening. If this is true, the treatment for spasticity should prevent the occurrence of muscle shortening during growth. We present the case of 1 child with cerebral palsy and spastic diplegia, for whom the treatment with selective dorsal rhizotomy was successful in improving the walking abilities. She did, however, develop muscle shortening during growth. In conclusion, the development of muscle shortening during growth in children with cerebral palsy and spastic paresis cannot be prevented by treatment for the spasticity alone.
    Journal of child neurology 02/2009; 24(5):625-7. · 1.59 Impact Factor
  • R. P. Weenink, W. J. R. van Ouwerkerk
    [Show abstract] [Hide abstract]
    ABSTRACT: Samenvatting Een zevenjarig meisje presenteerde zich met torticollis. Voorafgaand had zij een keelinfectie doorgemaakt. CT-scan van de cervicale wervelkolom toonde een atlantoaxiale subluxatie, ook wel het syndroom van Grisel genoemd. Patie¨nte werd behandeld met pijnstillers, spierverslappers en een harde halskraag gedurende een week.
    Tijdschrift voor kindergeneeskunde 01/2009; 77(1):42-43.
  • Developmental Medicine & Child Neurology 09/2008; 50(8):636-8. · 2.68 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Selective dorsal rhizotomy at the lumbar level is a neurosurgical procedure, which reduces spasticity in the legs. Its effect has mainly been studied in children with spastic cerebral palsy. Little is known about the outcome of selective dorsal rhizotomy in patients with neurodegenerative disorders. We report the clinical course after selective dorsal rhizotomy in 2 patients with progressive spasticity. Leg spasticity was effectively and persistently reduced in both patients, facilitating care and improving sitting comfort. However, spasticity of the arms and other motor disturbances, such as spontaneous extension spasms and the ataxia, increased gradually in time. Selective dorsal rhizotomy leads to a disappearance of leg spasticity in patients with a neurodegenerative disease. Other motor signs are not influenced and may increase due to the progressive nature of the underlying disease.
    Journal of child neurology 07/2008; 23(7):818-22. · 1.59 Impact Factor
  • R. Petru, S. M. Peerdeman, W. J. R. van Ouwerkerk
    [Show abstract] [Hide abstract]
    ABSTRACT: Traumatisch hersenletsel is een frequente oorzaak van morbiditeit en mortaliteit door ongevallen of mishandeling op de kinderleeftijd. Ernstig neurotrauma wordt gedefinieerd als een neurotrauma met een glasgow-comascore kleiner dan 9 op de plaats van het ongeval. Gebaseerd op de geldende richtlijnen voor de behandeling van ernstig neurotrauma bij kinderen en volwassenen en aanvullende recente literatuur wordt een overzicht gegeven van de beste huidige behandeling van deze patiënten gericht op de Nederlandse situatie. Hypotensie, shock en hypoxie zijn geassocieerd met een slechte uitkomst en moeten actief bestreden worden. Transport dient primair naar een gespecialiseerd traumacentrum te geschieden. Zo spoedig mogelijk dient een CT-scan verricht te worden, en een herhaling van dit onderzoek moet overwogen worden bij iedere neurologische verslechtering. Een operabele intracraniële bloeding met massa-effect is een indicatie voor chirurgische evacuatie. De basisbehandeling bestaat uit adequate ventilatie, normothermie, sedatie en het intact houden of optimaliseren van het interne milieu. De intracraniële druk dient door middel van frequent neurologisch onderzoek met gebruik van de (pediatrische) glasgow-comaschaal en/of via een ICP-meter te geschieden. Als behandeling van intracraniële drukverhoging zijn osmotische therapie, diepere sedatie, liquordrainage, opgelegde hypothermie, kortdurende hyperventilatie en decompressie craniëctomie effectief, hoewel de effecten op de uitkomst niet geheel duidelijk zijn. Voor het profylactisch gebruik van anti-epileptica, voor het barbituratencoma en voor spierverslappers is in het algemeen geen indicatie. Corticosteroïden zijn gecontra-indiceerd. Traumatic brain injury is a frequent cause of child morbidity and mortality resulting from both accidents and abusive head injury. Severe traumatic brain injury (TBI) is defined as brain injury with an initial (Pediatric) Glasgow Coma Score less than 9. Based on the current guidelines for the management of severe traumatic brain injury in children and adults and additional recent literature we give an overview of the current state of the art treatment of these patients as applicable to the situation in the Netherlands. Hypotension, shock and hypoxia are associated with an unfavorable outcome and need to be addressed actively. Patients should be transported directly to a specialized pediatric trauma center. The patient should receive a CT scan as soon as possible and repeating the scan should be considered with every deterioration of the neurological condition. Surgical evacuation of mass lesions should be performed as needed. Adequate ventilation, prevention of hyperthermia, sedation and maintenance of the interior environment are the cornerstones of the subsequent therapy. The patient should be frequently evaluated by neurological examination, the assessment of the (Pediatric) Glasgow Coma Scale and/ or through direct monitoring of the intracranial pressure. Hyperosmolar therapy, deeper sedation, CSF drainage, therapeutic hypothermia, short-term hyperventilation and decompressive craniectomy are effective in lowering the ICP, although their effects on long-term outcome are not fully established. There is no indication in general for anti-seizure prophylaxis, high-dose barbiturate therapy or neuromuscular blockade. The use of corticosteroids is contraindicated.
    Tijdschrift voor kindergeneeskunde 01/2008; 76(6):296-303.
  • D R Buis, W J R van Ouwerkerk, H Takahata, W P Vandertop
    [Show abstract] [Hide abstract]
    ABSTRACT: Intracranial aneurysms are very rare in early childhood. Because the location, morphology as well as the clinical and radiological presentation of these aneurysms seem to be different from those in adults, we performed a systematic review of the literature to discuss the clinical, morphological, and radiological features of intracranial aneurysms in the first year of life. A computerized search of both Pubmed and EMBASE from before 1966 to 2005 was performed. Included were all articles that dealt with cases in which an intracranial aneurysm was demonstrated in children under 1 year of age. We found 110 articles in which 131 cases of an intracranial aneurysm in children under 1 year were presented. The mean age at diagnosis of the aneurysm was 4.9+/-3.5 months with a male to female ratio of 1.1. There was a hemorrhagic presentation in 73% (n=96). The patients presenting with a hemorrhage were younger (mean 4.3 vs 6.7 months, P<0.001) and tended to have smaller-sized (i.e.<2.5 cm) aneurysms (P=0.07). The aneurysm was defined as traumatic or infectious in 15 and 13 cases, respectively. In 21% (n=27), there was various vascular or congenital co-morbidity. In 76%, the aneurysm was located in the anterior circulation. The prevalence of aneurysms on the middle cerebral artery (MCA) was nearly three times higher than on any other vessel. The mean aneurysm size was 1.8+/-1.4 cm, with 30 giant aneurysms (>2.5 cm). The giant aneurysms were significantly more often located in the posterior circulation (43 vs 16%, P=0.01). The mean period of follow-up was 13.6+/-24.8 months. The Glasgow Outcome Scale (GOS) could be derived in 106 cases: 50% had an excellent outcome (GOS of 5). The presentation of arterial aneurysms in children under the age of 1 year differs from that in adults with a significantly higher prevalence of giant aneurysms in the posterior circulation. The prevalence of aneurysms on the MCA is nearly three times higher than on any other vessel. The patients presenting with a hemorrhage were younger and tended to have smaller-sized aneurysms. Our study did not confirm the male predominance that has thus far been associated with pediatric aneurysms. The outcome is comparable or slightly better than in adults.
    Child s Nervous System 12/2006; 22(11):1395-409. · 1.24 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A systematic follow-up of infants with an obstetric brachial plexus lesion of C5 and C6 or the superior trunk showing satisfactory spontaneous recovery of shoulder and arm function except for voluntary shoulder exorotation, who underwent an accessory to suprascapular nerve transfer to improve active shoulder exorotation, to evaluate for functional recovery, and to understand why other superior trunk functions spontaneously recover in contrast with exorotation. In 54 children, an accessory to suprascapular nerve transfer was performed as a separate procedure at a mean age of 21.7 months. Follow-up examinations were conducted before and at 4, 8, 12, 24, and 36 months after operation and included scoring of shoulder exorotation and abduction. Intraoperative reactivity of spinatus muscles and additional needle electromyographic responses were registered after electrostimulation of suprascapular nerves. Histological examination of suprascapular nerves was performed. Trophy of spinatus muscles was followed by magnetic resonance imaging scanning. The influence of perinatal variables and results of ancillary investigations on outcome were evaluated. Exorotation improved from 70 degrees to functional levels exceeding 0 degrees, except in two patients. Abduction improved in 27 patients, with results of 90 degrees or more in 49 patients. Electromyography at 4 months did not show signs of denervation in 39 out of 40 patients. Intraoperative electrostimulation of suprascapular nerves elicited spinatus muscle reaction in 44 out of 48 patients. Histology of suprascapular nerves was normal. Preoperative magnetic resonance imaging scans showed only minor wasting of spinatus muscles in contrast with major wasting after successful operations. An accessory to suprascapular nerve transfer is effective to restore active exorotation when performed as the primary or a separate secondary procedure in children older than 10 months of age. Contradictory spontaneous recovery of other superior trunk functions and integrity of suprascapular nerves, as well as absence of spinatus muscle wasting direct to central nervous changes are possible main causes for the lack of exorotation.
    Neurosurgery 11/2006; 59(4):858-67; discussion 867-9. · 2.53 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Preoperative, reliable detection by ancillary investigations of spinal nerve root avulsions in infants with severe obstetric brachial plexus lesions to avoid ineffective operative repair from deceivingly intact but actually avulsed nerve roots. Ten infants were selected with an infrequent, severe dominant C7 lesion, primarily because of the anatomically distinct supraclavicular course of this spinal nerve. Three-dimensional constructive interference in steady-state magnetic resonance imaging (3D CISS MRI) studies under mild sedation were performed and evaluated for detection of avulsed nerve roots by two experienced neuroradiologists. Preoperative electrodiagnostics (electromyography and somatosensory evoked potentials) as well as intraoperative somatosensory potentials and muscle contractions after electrostimulation were recorded. Preoperative and intraoperative ancillary investigations were correlated with intraoperative findings in eight patients and clinical status in two children who recovered spontaneously. Despite two minor motion artifacts, the quality of the 3D CISS MRI studies was good. In 8 of 10 patients, prediction of root continuity was consistent with operative or clinical findings, and 2 remained doubtful. Preoperative and intraoperative electrodiagnostics tended not to correlate with intraoperative findings in this small, selected group. 3D CISS MRI provides good images of anterior and posterior spinal roots in infants with obstetric brachial plexus lesions. Images seem to allow accurate prediction of root avulsion in the majority of patients. In this study, electrodiagnostics were of limited value.
    Neurosurgery 12/2005; 57(5):930-40; discussion 930-40. · 2.53 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study is to evaluate the effect of selective dorsal rhizotomy (SDR) on functional abilities in a well-defined group of ambulatory children with spastic diplegia. Nine children were selected for SDR (mean age 65 months, range 43-82 months). Gross motor function was measured with the Gross Motor Function Measure (GMFM-88). Self-care was assessed with the Pediatric Evaluation of Disability Inventory (PEDI) and gait pattern was measured with the Edinburgh Visual Gait Score (EGS). There were nine single-case research designs with a 12-month follow-up after surgery. After 12 months the mean improvement in the total GMFM-88 scores was 8.8%. On an individual level, all patients improved significantly in comparison with baseline. Functional skills and care-giver assistance measured with the PEDI showed significant improvement. Improvement in gait was also found; in particular, better initial contact and heel-lift resulted in an increased EGS. In this well-defined group of ambulatory children SDR had a small but significant positive effect on gross motor function, self-care and gait pattern.
    Child s Nervous System 07/2005; 21(6):451-7. · 1.24 Impact Factor
  • Source
    W.J. R. van Ouwerkerk
    [Show abstract] [Hide abstract]
    ABSTRACT: Treatment strategy in infants with obstetric brachial plexus palsy (OBPP) largely depends on clinical neurological examination and the degree of improvement in the first 3 months. Usually, less severe lesions show early recovery within a few months, and prognosis for spontaneous recovery is good. However, sometimes the time course of improvement may differ and will not allow clinical differentiation from more severe types of lesions with less favorable prognosis. Ancillary preoperative investigations assist in determining the type, level, and extent of the nerve lesion. The role of electrodiagnosis in preoperative assessment of OBPP is depreciated by many, whereas others stress the importance of combining results from electromyography and nerve action potential recording to discriminate between a nerve conduction block and a root avulsion or to predict the severity of axonal injury or degeneration. There is no role for motor-evoked potentials in OBPP yet. For imaging of the brachial plexus in infants, magnetic resonance imaging has surpassed computed tomography–myelography as modality of choice. High-strength magnetic resonance scanners, applying different techniques in a noninvasive way, allow imaging of plexus structures with great detail. Detection of different nerve lesion types is possible, such as root avulsions or nerve ruptures, formation of pseudomeningoceles, neuromas, or scarring as well as deformities of the shoulder joints. Magnetic resonance imaging is becoming a great aid as a preoperative investigation in determining treatment strategy in infants with severe OBPP.
    01/2005;
  • [Show abstract] [Hide abstract]
    ABSTRACT: A case of a Suriname female occipito-parietal to occipito-parieto-temporal craniopagus twins is described. The girls were transferred to the VU University Medical Center (VUmc) in Amsterdam, the Netherlands, for further diagnostics and to analyze whether surgical separation was feasible and ethically justifiable. The multifactorial aspects of different treatment options are discussed. The twins underwent multiple investigations by a multidisciplinary team. Advanced imaging techniques with 3D-CT scan, MRI and MRA scans, image fusion techniques and, most importantly, cerebral angiography with balloon occlusion tests were performed. Because of a shared venous ring, with preferential drainage to the left child, and which endovascular balloon occlusion showed could not be separated, surgical separation of the twins with a fair chance of survival without additional neurological damage and with prospects of a good quality of life was regarded as impossible. In accordance with the parents' wishes, the twins were not separated and offered optimal integral conservative treatment.
    Child s Nervous System 09/2004; 20(8-9):625-34. · 1.24 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The authors performed a prospective study in which magnetic resonance (MR) imaging was conducted in 26 consecutive infants (mean age 5.6 months, range 2.7-14.5 months) in whom recovery from an obstetric lesion of the brachial plexus had been inadequate in the first 3 months of life. The purpose was to identify early secondary deformations of the shoulder in obstetrical brachial plexus lesions (OBPLs). Features of the shoulders were analyzed according to a standardized MR imaging protocol in patients with OBPLs. Measurements were made of the appearance of the glenoid, glenoid version, and the position of the humeral head. The appearance of the glenoid on the affected side was normal in only 11 shoulders. In the remainder it was convex in eight and biconcave in seven cases. The degree of humeral head subluxation was significantly greater (p = 0.001) in affected shoulders than in normal shoulders (152 and 170 degrees, respectively). The presence of abnormal glenoid retroversion and humeral head subluxation increased with age: there was a statistical difference (p = 0.001) between infants younger than 5 months of age and those who were older. Magnetic resonance imaging demonstrates shoulder-related anatomical and nerve root lesion, allowing evaluation of neural, osseous, and cartilaginous structures in younger children.
    Neurosurgical FOCUS 06/2004; 16(5):E9. · 2.49 Impact Factor

Publication Stats

317 Citations
51.11 Total Impact Points

Institutions

  • 2004–2010
    • VU University Medical Center
      • • Rehabilitation Medicine Clinic
      • • Department of Neurosurgery
      Amsterdamo, North Holland, Netherlands
  • 2009
    • Heliomare Rehabilitation Centre
      Berverwyk, North Holland, Netherlands
  • 2000–2006
    • VU University Amsterdam
      • Department of Neurosurgery
      Amsterdam, North Holland, Netherlands
  • 1999
    • Academisch Medisch Centrum Universiteit van Amsterdam
      • Department of Neurosurgery
      Amsterdam, North Holland, Netherlands