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P T de Jong

Publications and source records attributed to P T de Jong.

At least 19 recordsLinked to original sources
PubMed2006

Intertrochanteric osteotomies do not impair long-term outcome of subsequent cemented total hip arthroplasties.

UNLABELLED: The literature contains contradictory evidence as to whether previous proximal femoral osteotomy impairs the long-term outcomes of total hip arthroplasty. We therefore examined whether our patients with cemented total hip arthroplasties after previous osteotomies had inferior outcomes. We also investigated whether the intraoperative complication rate and the clinical and radiologic outcomes were altered by a previous osteotomy. We compared a group of 121 consecutive patients who had total hip arthroplasties (1974-1993) after osteotomies with a group of 290 consecutive patients who had total hip arthroplasties (1974-1987) without previous surgery. There was no difference in survival rate. There was a 10-year survival rate of 90% compared with 92% for the control group. The 15-year survival rates were 83% and 81%, respectively. There were no differences in radiologic and clinical followups. Intraoperative perforation of the femur occurred more often in patients with a total hip arthroplasty after an osteotomy. Our data suggest the long-term outcome of a cemented total hip arthroplasty is not impaired by a previous well-performed osteotomy. LEVEL OF EVIDENCE: Therapeutic study, Level III (retrospective comparative study). See the Guidelines for Authors for a complete description of levels of evidence.

Adult↗
PubMed2006

Total hip replacement with a superolateral bone graft for osteoarthritis secondary to dysplasia: a long-term follow-up.

We evaluated the long-term results of 116 total hip replacements with a superolateral shelfplasty in 102 patients with osteoarthritis secondary to developmental dysplasia of the hip. After a mean follow-up of 19.5 years (11.5 to 26.0), 14 acetabular components (12%) had been revised. The cumulative survival at 20 years was 78%, with revision for loosening of the acetabular component as the end-point. All grafts were well integrated and showed remodelling. In six grafts some resorption had occurred under the heads of the screws where the graft was not supporting the socket. Apart from these 14 revisions, seven acetabular components had possible radiological signs of loosening at a mean follow-up of 14.5 years, one had signs of probable loosening, and five had signs of definite loosening. These results indicate that this technique of bone grafting for acetabular reconstruction in hip dysplasia is a durable solution for cemented acetabular components.

Acetabulum↗
PubMed2004

Weber rotation total hip replacement: a prospective 5- to 20-year followup study.

Between 1974 and 1989, 315 primary total hip replacements (274 patients) were done using the cemented Weber Rotation prosthesis and standardized operative technique, which was modified for the stem in 1978. After the first postoperative year, all patients had routine clinical and radiologic examinations at 2-year intervals. Twenty-one patients (22 hips) were lost to followup. At the most recent followup, 30 of 293 hips (253 patients) had been revised: 24 hips for aseptic loosening, five hips for infection, and one hip for a femoral fracture. Survivorship analyses with revision for aseptic loosening as an end point for the 315 hips showed 93% and 78% survival after 10 and 15 years, respectively. Separate survival analyses for the socket showed 99% and 89% survival after 10 and 15 years, respectively. The stem had a survival of 94% and 81%, respectively, during the same time. Survival at 15 years with radiologic evidence of loosening as an end point was 85% for the socket and 72% for the stem. The cementing technique and the design of the acetabular component significantly influenced the rate of loosening. Survivorship analyses with revision for aseptic loosening of the socket, using a modified second generation cementing technique and a hemispheric socket, showed 100% survival after 10 years and 98% after 13 years.

Adult↗
PubMed2003

[What do you actually see? Visual impairments and their simulation for well-seeing subjects].

Most physicians know little about how persons with limited vision perceive something. Sometimes, simple technical aids can make it possible to get an idea as to what a visual disorder means to the person involved. Examples of this are the wearing of glasses of varying positive power and light transmittance, or the study of case histories, paintings and photographic simulations. Among the latter are a woman who painted what she 'saw' with her removed eye, an anophthalmic man who painted from memory, and the painting of a protanopic artist who chose colours by reading the labels on the paint tubes. Thus one may gain insight in disturbances such as phantom images, diminished visual acuity and visual field loss, metamorphopsia, diplopia, dazzling, and visual agnosia. And also in disturbed image fusion, in depth and stereoscopic vision, dark adaptation and colour vision, as well as diminishing visual functions at high age. This article contains colour illustrations that simulate the disturbances.

Aging↗
PubMed2001

Is open-angle glaucoma associated with early menopause? The Rotterdam Study.

The authors examined the association between age at menopause and open-angle glaucoma among women aged > or = 55 years in the population-based Rotterdam Study (1990--1993). Information on age and type of menopause was obtained by interview. Subjects (n = 3,078) were stratified into three categories according to age at menopause: <45 years, 45--49 years, and > or = 50 years, with the last group serving as the reference group. Diagnosis of open-angle glaucoma was based on the presence of a glaucomatous visual field defect and glaucomatous optic neuropathy. Open-angle glaucoma was diagnosed in 78 women with a natural menopause and 15 women with an artificial menopause. In the category of natural menopause, women who went through menopause before reaching the age of 45 years had a higher risk of open-angle glaucoma than the reference group (odds ratio = 2.6; 95% confidence interval: 1.5, 4.8), after adjustment for age and use of hormone replacement therapy. Among women who went through menopause between the ages of 45 and 49 years, the odds ratio was 1.1 (95% confidence interval: 0.7, 2.0). These findings suggest that early menopause is associated with a higher risk of open-angle glaucoma.

Adult↗
PubMed2001

Prevalence and causes of visual field loss in the elderly and associations with impairment in daily functioning: the Rotterdam Study.

OBJECTIVES: To determine the prevalence and causes of visual field loss (VFL) and the association between VFL and indicators of impairment in daily functioning. DESIGN: Population-based cohort study. SETTING: Suburb of Rotterdam, the Netherlands. PARTICIPANTS: Community-dwelling elderly residents (n = 6250). MAIN OUTCOME MEASURE: Visual field loss on suprathreshold static, Goldmann kinetic perimetry, or both. METHODS: Suprathreshold testing of the central visual field was performed on both eyes and repeated if results were abnormal or unreliable. Goldmann perimetry was performed to confirm defects. Causes were determined using ophthalmologic and neurologic examination data and medical records. Impairment was assessed using data from interviews and medical records on disability in daily life, falling, and fractures. RESULTS: The overall prevalence of VFL was 5.6% (3.0% in those aged 55-64 years to 17.0% in those > or =85 years); glaucoma was the leading cause in all age groups. Before age 75 years, other optic nerve diseases and stroke ranked second and third, respectively, as did age-related macular degeneration and retinal vascular occlusive disease, respectively, after this age. Also, after adjustment for visual acuity, VFL was associated with disability, diminished enjoyment of reading and watching television, and a higher risk of incident falling. Risk of incident hip fracture was not increased. CONCLUSIONS: Visual field loss is present in 1 of every 20 community-dwelling elderly people and is associated with impaired daily functioning. Glaucoma is the leading cause in all age groups. Other high-ranking causes, some of which are partly preventable, vary by age.

Activities of Daily Living↗
PubMed2001

Risk factors for age-related macular degeneration: Pooled findings from three continents.

OBJECTIVE: To assess the prevalence and potential risk factors for late age-related macular degeneration (AMD) in three racially similar populations from North America, Europe, and AUSTRALIA: DESIGN: Combined analysis of population-based eye disease prevalence data. PARTICIPANTS: There were 14,752 participants with gradable photographs from the Beaver Dam Eye Study (n = 4756), Rotterdam Study (n = 6411), and Blue Mountains Eye Study (n = 3585). MAIN OUTCOME MEASURES: AMD diagnosis was made from masked grading of stereo macular photographs. Final classification of AMD cases was agreed by consensus between study investigators. RESULTS: AMD prevalence was strongly age related. Overall, AMD was present in 0.2% of the combined population aged 55 to 64 years, rising to 13% of the population older than 85 years. Prevalence of neovascular AMD (NV) increased from 0.17% among subjects aged 55 to 64 years to 5.8% for those older than 85 years. Prevalence of pure geographic atrophy (GA) increased from 0.04% to 4.2% for these age groups. There were no significant gender differences in the prevalence of NV or GA. Subjects in the Rotterdam population had a significantly lower age-adjusted and smoking-adjusted risk of NV than subjects in the Beaver Dam and Blue Mountains populations. Apart from age, tobacco smoking was the only risk factor consistently associated with any form of AMD in all sites separately and in pooled analyses over the three sites. CONCLUSIONS: These combined data from racially similar communities across three continents provide strong and consistent evidence that tobacco smoking is the principal known preventable exposure associated with any form of AMD.

Adult↗
PubMed2001

Incidence and progression rates of age-related maculopathy: the Rotterdam Study.

PURPOSE: To describe the incidence rate of age-related macular degeneration (AMD) and the progression rates of early stages of age-related maculopathy (ARM), and to study the hierarchy of fundus features that determine progression. METHODS: A group of 4953 subjects aged 55 years and older living in Rotterdam, The Netherlands, was studied at baseline and at 2-year follow-up to determine the incidence of neovascular and atrophic AMD. A subgroup of 1244 subjects was studied for progression of early stages of ARM. Fundus transparencies were graded for features of ARM using the International Classification System. ARM was stratified in four exclusive stages, according to type of drusen and presence of pigmentary irregularities. RESULTS: The overall 2-year cumulative incidence of AMD was 0.2%, increasing to 1.8% in subjects of 85 years and older. Of those in the early stages, one fourth showed progression to a more severe stage. The most important predictors for progression were more than 10% of macular area covered by drusen (odds ratio [OR] 5.7, 95% confidence interval [CI] 2.9-11.3), presence of depigmentation (OR 4.0, 95% CI 2.5-6.4), and hyperpigmentation (OR 3.4, 95% CI 2.1-5.4). CONCLUSIONS: The incidence of AMD appears to be lower in The Netherlands than in the United States. Progression of early ARM stages occurs in a distinct pattern at a stable rate, with a large area of drusen and presence of pigmentary changes as the most important predictors.

Age Distribution↗
PubMed2000

Mutations in ABCC6 cause pseudoxanthoma elasticum.

Pseudoxanthoma elasticum (PXE) is a heritable disorder of the connective tissue. PXE patients frequently experience visual field loss and skin lesions, and occasionally cardiovascular complications. Histopathological findings reveal calcification of the elastic fibres and abnormalities of the collagen fibrils. Most PXE patients are sporadic, but autosomal recessive and dominant inheritance are also observed. We previously localized the PXE gene to chromosome 16p13.1 (refs 8,9) and constructed a physical map. Here we describe homozygosity mapping in five PXE families and the detection of deletions or mutations in ABCC6 (formerly MRP6) associated with all genetic forms of PXE in seven patients or families.

ATP-Binding Cassette Transporters↗
PubMed2000

The APO(*)E3-Leiden mouse as an animal model for basal laminar deposit.

AIM: To investigate the APO(*)E3-Leiden mouse as an animal model for age related maculopathy (ARM) related extracellular deposits. METHODS: Eyes were obtained from APO(*)E3-Leiden transgenic mice on a high fat/cholesterol (HFC) diet (n=12) or on a normal mouse chow (n=6), for 9 months. As controls, eyes were collected from APO-E knockout mice on the same diets. From each mouse one eye was processed for microscopic evaluation and immunohistochemistry with a polyclonal antibody directed against human apo-E. Electron microscopy was also performed. RESULTS: All 12 eyes of the APO(*)E3-Leiden mice on an HFC diet contained basal laminar deposit (BLD; class 1 to class 3), whereas two of six APO(*)E3-Leiden mice on normal chow showed BLD class 1. The ultrastructural aspects of this BLD were comparable with those seen in early BLD in humans, and BLD showed immunoreaction with anti-human-apo-E antibodies. No BLD was found in any of the control mice. Drusen were not detected in any of the mice. CONCLUSION: These results indicate that APO(*)E3-Leiden mice can be used as animal model for the pathogenesis of BLD, and that a HFC diet enhances the accumulation of this deposit. Furthermore, this study supports the previously suggested involvement of dysfunctional apo-E in the accumulation of extracellular deposits in ARM.

Animals↗
PubMed2000

Sorsby fundus dystrophy without a mutation in the TIMP-3 gene.

AIMS: To examine a large family with an autosomal dominant fundus dystrophy and to investigate whether or not mutations in TIMP-3 gene were involved. METHODS: A large family of 58 individuals with an autosomal dominant fundus dystrophy was examined ophthalmologically. A DNA linkage analysis in the 22q12.1-q13.2 region was performed. The TIMP-3 gene was screened for mutations in all five exons. RESULTS: In this large family 15 individuals were affected. All other individuals were found to be clinically unaffected. Pisciform flecks in the midperiphery and drusen-like deposits were the most typical ophthalmological finding in this family and were encountered from the fifth decade on. Chorioretinal atrophy and neovascularisation with disciform lesions characterised the disease from the sixth decade on. Linkage analysis using an affected only analysis, showed a maximum positive lod score of 3.94 at theta = 0.0 with marker D22S283. No mutations possibly causing Sorsby fundus dystrophy were found in either the exonic sequences, the promotor region, or the 3'UTR. CONCLUSION: The family in this pedigree has an autosomal dominant fundus dystrophy, which is most probably Sorsby fundus dystrophy. Although, in the linkage analysis, significant positive lod scores were found with the region 22q12.1-q13.2, no causative mutations could be identified in the TIMP-3 gene.

Aged↗
PubMed2000

Changing views on open-angle glaucoma: definitions and prevalences--The Rotterdam Study.

PURPOSE: To create a quantitative basis for diagnostic criteria for open-angle glaucoma (OAG), to propose an epidemiologic definition for OAG based on these, and to determine the prevalence of OAG in a general white population. METHODS: Of the 7983 subjects 55 years of age or older participating in the population-based Rotterdam Study, 6756 subjects participated in the ophthalmic part of this study (6281 subjects living independently and 475 in nursing homes). The criteria for the diagnosis of OAG were based on ophthalmoscopic and semiautomated Imagenet estimations of the optic disc such as vertical cup-to-disc ratio (VCDR), minimal width of neural rim, or asymmetry in VCDR between both eyes, and visual field testing with kinetic Goldmann perimetry. All criteria for the diagnosis of OAG were assessed in a masked way independently of each other. RESULTS: Mean VCDR on ophthalmoscopy was 0.3 and with Imagenet 0.49, and the 97.5th percentile for both was 0.7. The prevalence of glaucomatous visual field defects was 1.5%. Overall prevalence of definite OAG in the independently living subjects was 0.8% (95% confidence interval [CI] 0.6, 1.0; 50 cases). Prevalence of OAG in men was double that in women (odds ratio 2.1; 95% CI 1.2, 3.6). Different commonly used criteria for diagnosis of OAG resulted in prevalence figures ranging from 0.1% to 1.2%. CONCLUSIONS: The overall prevalence of OAG in the present study was comparable to most population-based studies. However, prevalence figures differed by a factor of 12 when their criteria for OAG were applied to this population. A definition for definite OAG is proposed: a glaucomatous optic neuropathy in eyes with open angles in the absence of history or signs of secondary glaucoma characterized by glaucomatous changes based on the 97.5 percentile for this population together with glaucomatous visual field loss. In the absence of the latter or of a visual field test, it is proposed to speak of probable OAG based on the 99.5th or possible OAG based on the 97.5th percentiles of glaucomatous disc changes for a population under study.

Age Distribution↗
PubMed1999

Pseudoxanthoma elasticum maps to an 820-kb region of the p13.1 region of chromosome 16.

We have performed linkage analysis on 21 families with pseudoxanthoma elasticum (PXE) using 10 polymorphic markers located on chromosome 16p13.1. The gene responsible for the PXE phenotype was localized to an 8-cM region of 16p13.1 between markers D16S500 and D16S3041 with a maximum lod score of 8.1 at a recombination fraction of 0.04 for marker D16S3017. The lack of any locus heterogeneity suggests that the major predisposing allele for the PXE phenotype is located in this region. Haplotype studies of a total of 36 PXE families identified several recombinations that further confined the PXE gene to a region (< 1 cM) between markers D16S3060 and D16S79. This PXE locus was identified within a single YAC clone and several overlapping BAC recombinants. From sequence analysis of these BAC recombinants, it is clear that the distance between markers D16S3060 and D16S79 is about 820 kb and contains a total of nine genes including three pseudogenes. We predict that mutations in one of the expressed genes in the locus will be responsible for the PXE phenotype in these families.

Alleles↗
PubMed1999

Is age-related maculopathy associated with Alzheimer's Disease? The Rotterdam Study.

The authors examined the relation between age-related maculopathy and Alzheimer's disease in the Rotterdam Study, a prospective population-based study in the Netherlands. From 1990 to mid-1993, subjects aged 75 years or older (n = 1,438) were screened for the presence of age-related maculopathy and Alzheimer's disease, and follow-up examinations were conducted from mid-1 993 to the end of 1994. Subjects with advanced age-related maculopathy at baseline showed an increased risk of incident Alzheimer's disease (relative risk = 2.1, 95% confidence interval: 1.1, 4.3; adjusted for age and gender), but this risk decreased after additional adjustment for smoking and atherosclerosis (relative risk = 1.5, 95% confidence interval: 0.6, 3.5). These findings suggest that the neuronal degeneration occurring in age-related maculopathy and Alzheimer's disease may, to some extent, have a common pathogenesis.

Aged↗
PubMed1999

Quantitative visual fields under binocular viewing conditions in primary and consecutive divergent strabismus.

BACKGROUND: Although there have been a number of studies on the size of the suppression scotoma in divergent strabismus, there have been no reports on the full extent (i.e. size as well as depth) of this scotoma. METHODS: Binocular static perimetry was used to measure suppression scotomas in five patients with primary divergent strabismus and ten patients with consecutive divergent strabismus. Four control subjects were also included in the study. With two modified Friedmann visual field analysers, we measured the visual field of both eyes under monocular and binocular viewing conditions. The objective angle of squint ranged from 3 degrees to 25 degrees. Best corrected visual acuity was at least 0.4, but mostly 1.0 in both eyes. RESULTS: All subjects had normal visual fields for each eye under monocular viewing conditions. In 12 of the 15 subjects, we found a large area of suppression encompassing the projection of the fixation point as well as that of the fovea in the non-fixating eye under binocular viewing conditions. In 2 of these 12 patients, one with primary and one with consecutive divergent strabismus, the area of suppression was located nasally to the position of the fovea in the field of the non-fixating eye (nasal hemisuppression). In another two patients with divergent squint combined with vertical deviation, a small fixation-point suppression scotoma was found. The depth of suppression ranged from 3 dB to 16 dB. In one subject only, no suppression was found. CONCLUSIONS: Our findings indicate that the shape of the suppression scotoma is not related to the origin of divergent strabismus or to the angle of squint. Our results also indicate that the critical age for the development of suppression in divergent squint might be up to 14 years.

Adolescent↗