C. M. A. M. van der Horst
University of Amsterdam
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Featured researches published by C. M. A. M. van der Horst.
The New England Journal of Medicine | 1998
C. M. A. M. van der Horst; P. H. L. Koster; C.A.J.M. de Borgie; P. M. M. Bossuyt; M.J.C. van Gemert
BACKGROUND Port-wine stains can be treated with a flash-lamp-pumped pulsed-dye laser, but it is uncertain whether this treatment is more effective if administered early in life, when the skin is thinner and the lesion is smaller. METHODS We prospectively studied 100 patients with a previously untreated port-wine stain of the head or neck. They were treated with the flash-lamp-pumped pulsed-dye laser and divided into four age groups (0 to 5, 6 to 11, 12 to 17, and 18 to 31 years). The outcome measure was lightening of the port-wine stain (reduction in the difference in color between the skin with the stain and contralateral healthy skin) as measured with a colorimeter after an average of five treatments (range, three to seven) of the entire lesion. RESULTS Of the 100 patients, 11 could not be included in the analysis because they had received fewer than three or more than seven treatments, had an erroneous base-line color measurement, or were lost to follow-up. The sizes, locations, and colors of the port-wine stains were similar among the groups. When all 89 patients were analyzed together, the average reduction in the difference in color between the skin with the port-wine stain and contralateral healthy skin was 40 percent. The differences between age groups in the average reduction in color differences were not significant (P= 0.26). By the end of the study, only 7 of 89 patients had completed laser therapy, and in no case was clearance complete. Treatment was discontinued in all seven because the last three treatments did not lead to further lightening. CONCLUSIONS We found no evidence that treatment of port-wine stains with the flash-lamp-pumped pulsed-dye laser in early childhood is more effective than treatment at a later age.
Journal of Bone and Joint Surgery-british Volume | 2003
C. C. Breugem; Mario Maas; S. J. M. Breugem; G. R. Schaap; C. M. A. M. van der Horst
Vascular malformations are rare congenital lesions which often have associated skeletal changes. Over a period of ten years, 90 patients at our clinic had a vascular anomaly of the lower limb, examined by either CT or MRI. Of these, 18 (20%) had bony involvement. A questionnaire was sent to these patients (8 men, 10 women) to evaluate their age of presentation, initial symptoms and current complaints. Radiological imaging revealed 15 low- and three high-flow lesions. The mean age at presentation to a physician was six years of age. Pain was the most common complaint. Disparity in leg length of 2 cm or more was observed in ten patients. Of the 16 patients with muscle infiltration, 13 had four or more muscles involved. Treatment by resection alone would require radical surgery.
Journal of Bone and Joint Surgery-british Volume | 2008
J. M. Staudt; Mark J. C. Smeulders; C. M. A. M. van der Horst
Compartment pressures have not previously been studied in healthy children. We compared the pressures in the four lower leg compartments of healthy children with those of healthy adults. We included patients aged between two months and six years, and measured the pressures in 80 compartments of 20 healthy children using simple needle manometry. Measurements were repeated in a control group of 20 healthy adults. The mean compartment pressure in the lower leg in children was significantly higher than in adults (p < 0.001). On average, pressures in the four compartments varied between 13.3 mmHg and 16.6 mmHg in the children and between 5.2 mmHg and 9.7 mmHg in the adults. The latter is in accordance with those recorded in the literature. The mean arterial pressure did not relate to age or to pressure in the compartment. The findings of this study that the normal compartment pressure of the lower leg in healthy children is significantly higher than that in adults may be of considerable significance in clinical decision-making in children of this age.
Knee Surgery, Sports Traumatology, Arthroscopy | 2015
Miryam C. Obdeijn; N. Bavinck; Christophe Mathoulin; C. M. A. M. van der Horst; Marlies P. Schijven; Gabriëlle J. M. Tuijthof
PurposeArthroscopy has assumed an important place in wrist surgery. It requires specific operative skills that are now mainly acquired in the operating room. In other fields of endoscopic surgery, e-learning and virtual reality (VR) have introduced new perspectives in teaching skills. This leads to the following research question: Could the current way of teaching wrist arthroscopy skills be supported using new educational media, such as e-learning and simulator training?MethodThe literature was searched for available methods of teaching endoscopic skills. Articles were assessed on the evidence of validity. In addition, a survey was sent to all members of the European Wrist Arthroscopy Society (EWAS) to find out whether hand surgeons express a need to embrace modern educational tools such as e-learning or simulators for training of wrist arthroscopy skills.ResultsThis study shows that the current way of teaching wrist arthroscopy skills can be supported using new educational media, such as e-learning and simulator training. Literature indicates that e-learning can be a valuable tool for teaching basic knowledge of arthroscopy and supports the hypothesis that the use of virtual reality and simulators in training enhances operative skills in surgical trainees. This survey indicates that 55 out of 65 respondents feel that an e-learning program would be a valuable asset and 62 out of the 65 respondents are positive on the additional value of wrist arthroscopy simulator in training.ConclusionStudy results support the need and relevance to strengthen current training of wrist arthroscopy using e-learning and simulator training.Level of evidenceV.
Lasers in Medical Science | 1999
C. M. A. M. van der Horst; T.G.J. van Eijk; C.A.J.M. de Borgie; P. H. L. Koster; P.M. Struycken; Simon D. Strackee
Abstract. Patients with a port-wine stain applying for laser treatment often mentioned having a member in the family with a similar birthmark. Of 280 consecutive new patients with a port-wine stain 55 mentioned relatives with the same anomaly. Family tendency (19.6%) for vascular malformations in our group was significantly higher than mentioned by others. Pedigrees were made of 32 families with two or more affected members, including probands. We present nine representative pedigrees of families with three or more members affected by port-wine stains. In these families no clear mode of inheritance can be discerned. Genetic linkage studies identified causative gene defects in certain venous malformations and Rendu–Osler–Weber disease. Knowledge of new theories on angiogenesis and molecular genetics has to be linked to our patients with familial port-wine stains.
Plastic and Reconstructive Surgery | 1998
P. H. L. Koster; P. M. M. Bossuyt; C. M. A. M. van der Horst; Geert H. M. Gijsbers; M.J.C. van Gemert
&NA; A generally accepted method to assess the clinical outcome of laser treatment of portwine stains is not available. This paper describes the development and evaluation of a comprehensive questionnaire for the assessment of the following portwine stain characteristics: color (hue and lightness), sharpness of boundary, pigmentation, size, shape, skin surface‐structure, and hypertrophy of underlying tissue. The questionnaire was applied to photographs of 70 patients with previously untreated portwine stains in the head/neck area. Photographs were taken before treatment and after five treatments of the entire portwine stain with a flashlamp pumped pulsed dye laser. Each photograph was evaluated separately by a panel of five professionals: the treating physician, two plastic surgeons, a dermatologist, and a clinical photographer. Treatment results were assessed by comparing ratings before and after treatment. Agreement among raters was acceptable for all portwine stain characteristics, as was shown by weighted kappa analysis. The reliability of the answers was further improved by taking the average rating of the five panel members. The scores thus obtained were very reliable, with Cronbach alpha coefficients of 0.8 on average. After five treatments of the entire portwine stain, the most considerable changes were measured in the ratings for color (lightening of the stain by 33 percent), boundary (sharpness reduced by 38 percent), and size (13‐percent decrease). Using the questionnaire can be helpful in the design of comparative clinical trials on portwine stain treatment and may facilitate comparison of treatment results between different treatment centers and/or different lasers. (Plast. Reconstr. Surg. 102: 42, 1998.)
Chirurgie De La Main | 2013
E. Hajder; M.C. de Jonge; C. M. A. M. van der Horst; Miryam C. Obdeijn
The purpose of this study was to describe the technique and usefulness of ultrasound-guided intrasheath injection of triamcinolone in the treatment of de Quervains disease (dQD). Our study was retrospective in design. Seventy-one wrists of 62 patients who were treated with an ultrasound-guided triamcinolone injection for dQD were included. A literature search was performed to compare our results. In the literature we found supportive evidence that accurate injection of triamcinolone in the first dorsal compartment of the wrist is important for a good outcome. In this retrospective study we found that treatment with ultrasound-guided injections of triamcinolone is both safe and effective. After two injections, 91% of the patients had good long-term results, which is a higher cure rate than found in most other studies. Furthermore, we found that Finkelsteins test can give a false positive result. Therefore, ultrasound should not only be considered to improve the treatment outcome, but can also be useful as a diagnostic tool in the management of de Quervains disease.
British Journal of Dermatology | 2018
Sophie E.R. Horbach; C. M. A. M. van der Horst; F. Blei; C.J.M. van der Vleuten; Ilona J. Frieden; G.T. Richter; Laurence M. Boon; Phyllis I. Spuls
An important limitation in vascular malformation research is the heterogeneity in outcome measures used for the evaluation of treatment outcome.
Plastic and Reconstructive Surgery | 2017
Sophie E.R. Horbach; Dirk T. Ubbink; Fabienne E. Stubenrouch; Mark J.W. Koelemay; C.J.M. van der Vleuten; B.H. Verhoeven; Jim A. Reekers; L.J. Schultze Kool; C. M. A. M. van der Horst
Background: In shared decision-making, clinicians and patients arrive at a joint treatment decision, by incorporating best available evidence and the patients’ personal values and preferences. Little is known about the role of shared decision-making in managing patients with congenital vascular malformations, for which preference-sensitive decision-making seems obvious. The authors investigated preferences regarding decision-making and current shared decision-making behavior during physician-patient encounters. Methods: In two Dutch university hospitals, adults and children with congenital vascular malformations facing a treatment-related decision were enrolled. Before the consultation, patients (or parents of children) expressed their preference regarding decision-making (Control Preferences Scale). Afterward, participants completed shared decision-making–specific questionnaires (nine-item Shared Decision-Making Questionnaire, CollaboRATE, and satisfaction), and physicians completed the Shared Decision-Making Questionnaire–Physician questionnaire. Consultations were audiotaped and patient involvement was scored by two independent researchers using the five-item Observing Patient Involvement instrument. All questionnaire results were expressed on a scale of 0 to 100 (optimum shared decision-making). Results: Fifty-five participants (24 parents and 31 adult patients) were included. Two-thirds preferred the shared decision-making approach (Control Preferences Scale). Objective five-item Observing Patient Involvement scores were low (mean ± SD, 31 ± 15), whereas patient and physician Shared Decision-Making Questionnaire scores were high, with means of 68 ± 18 and 68 ± 19, respectively. The median CollaboRATE score was 93. There was no clear relationship between shared decision-making and satisfaction scores. Conclusions: Although adults and parents of children with vascular malformations express a strong desire for shared decision-making, objective shared decision-making behavior is still lacking, most likely because of poor awareness of the shared decision-making concept among patients, parents, and physicians. To improve shared decision-making practice, targeted interventions (e.g., decision aids, staff training) are essential.
Clinical Otolaryngology | 2016
Hanneke Basart; A. M. König; J. H. Bretschneider; C. E. L. Hoekstra; K. P. Q. Oomen; B. Pullens; Rico N. P. M. Rinkel; C. D. L. van Gogh; C. M. A. M. van der Horst; Raoul C. M. Hennekam
Robin Sequence (RS) is usually defined as the combination of micrognathia, glossoptosis and upper airway obstruction. No objective criteria to diagnose RS exist. To compare management strategy results, a single RS definition using objective criteria is needed. The most frequently used primary diagnostic tool for glossoptosis is awake Flexible Fiberoptic Laryngoscopy (aFFL).