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G Rudolph

Publications and source records attributed to G Rudolph.

At least 37 records · Page 2Linked to original sources
PubMed2001

[LEOPARD syndrome with iris-retina-choroid coloboma. Discordant findings in monozygotic twins (MIM # 151 100)].

INTRODUCTION: The LEOPARD syndrome is an autosomal dominant inherited disease with severe lentiginosis associated with various abnormalities such as electrocardiographic abnormalities, ocular hypertelorism, pulmonary stenosis, abnormalities of the genitalia, retardation of growth and deafness. Ocular manifestations such as coloboma of the iris, the retina and the choroid have not been reported so far. PATIENTS: We report the cases of two 10-year-old identical twins and their mother, showing typical manifestations consistent with the LEOPARD syndrome. Additionally, colobomas of the iris, the retina and the choroid were detected. RESULTS: In addition to the findings typical for the LEOPARD syndrome, we observed unusual ocular abnormalities in all three patients. It represents a discordant phenotype in monozygotic twins. CONCLUSION: LEOPARD syndrome is a disease with multiple alterations and abnormalities. Although ocular malformations seem to be rare, an ophthalmological examination is recommended in order to initiate early visual rehabilitation.

Adult↗
PubMed2001

X-linked ocular albinism (Nettleship-Falls): a novel 29-bp deletion in exon 1. Carrier detection by ophthalmic examination and DNA analysis.

BACKGROUND: Mutations in the OA1 gene on the short arm of the X chromosome are known to cause X-linked ocular albinism (x1OA) in males. A four-generation family with this disorder, including asymptomatic carrier females, was investigated by molecular analysis of the OA1 gene. METHODS: DNA samples were available from 22 individuals of this family, including 6 affected males and 6 obligate carriers. The nine exons of the OA1 gene were amplified and further analyzed by SSCP and sequencing. RESULTS: A detailed clinical examination of the index patient and two female carriers showed the typical signs of ocular albinism. Visual evoked potential responses showed markedly asymmetrical responses from the two hemispheres in the affected person as well as in the carriers, as a result of misrouting and decussation of optic nerve fibers. Molecular genetic analysis demonstrated a previously undescribed 29-bp deletion at position 225-253 in exon 1 of the OA1 gene, which segregated in the family. CONCLUSION: Clinical examination combined with molecular genetic analysis enhances the potential for a precise diagnosis for persons at risk of x1OA and provide an accurate basis for genetic counseling.

Adult↗
PubMed2001

Correlations between motor persistence and plasma levels in methylphenidate-treated boys with ADHD.

Following a 0.9 mg/kg methylphenidate loading dose, serial plasma level determinations, self-scored mood ratings, and measures of motor persistence were gathered on eight previously unmedicated boys with attention deficit disorder with hyperactivity (ADHD) during a 9-h period. The measures were repeated using the same loading dose after 6 months of maintenance treatment with methylphenidate (1.3 mg/kg x d). Kinetic-dynamic modelling suggests inverse correlative relationships between motor performance errors and plasma levels. Pharmacokinetic parameters did not change between acute and maintenance drug treatment phases, and there was no evidence of long-term tolerance.

Adolescent↗
PubMed2001

Retinal detachment and cataract, facial dysmorphism, generalized osteoporosis, immobile spine and platyspondyly in a consanguinous kindred--a possible new syndrome.

We report on a consanguineous family with 6 children (out of 7) affected by a spondylo-ocular syndrome. Clinical features include cataract, loss of vision due to retinal detachment, facial dysmorphism, facial hypotonia, normal height with disproportional short trunk, immobile spine with thorakal kyphosis and reduced lumbal lordosis. On ophthalmological examination of the index patient, a dense cataract and complete retinal detachment could be detected on the right eye. On the left eye, an absent lens nucleus was found, but no retinal detachment. On radiological examination, there was generalized moderate osteoporosis; the spine showed marked platyspondyly and the bone age was advanced. On laboratory investigations, a normal excretion of amino acids, mucopolysaccharides and oligosaccharides could be found. The phenotypical spectrum observed in the 6 affected individuals was rather uniform. The karyotype was normal in all affected children. This hitherto undescribed combination of oculo-skeletal symptoms shows most resemblance with connective tissue disorders, suggesting a range of candidate genes for mutation analysis.

Abnormalities, Multiple↗
PubMed2001

EFEMP1 is not associated with sporadic early onset drusen.

The early onset of multiple drusen in the posterior pole of the retina is characteristic of a group of macular dystrophies often referred to as dominant or radial drusen. At least two forms, Doyne honeycomb retinal dystrophy (DHRD) and Malattia Leventinese (MLVT), are associated with a single missense mutation (R345W) in the gene encoding the EGF-containing fibulin-like extracellular matrix protein-1 (EFEMP1) and are now thought to represent a single entity. Here, we present a further evaluation of the role of EFEMP1 in the pathogenesis of sporadic forms of early onset drusen. We analyzed all coding exons of the EFEMP1 gene by SSCP analysis in 14 unrelated individuals with early onset of multiple drusen and no apparent family history of the disease. In this patient group, we did not detect the R345W mutation or any other disease-associated mutation. Three different polymorphisms and two intragenic polymorphic repeats were present in similar frequencies in the patients and control individuals. We conclude that EFEMP1 is unlikely to be involved in the disease in this patient group. This suggests that mutations in a different as yet unknown gene or genes may lead to the early onset drusen phenotype.

Adult↗
PubMed2000

Carrier assessment in families with lowe oculocerebrorenal syndrome: novel mutations in the OCRL1 gene and correlation of direct DNA diagnosis with ocular examination.

Lowe oculocerebrorenal syndrome (OCRL) (MIM 309000) is a rare X-linked multisystem disorder characterized by congenital cataracts, muscular hypotonia, areflexia, mental retardation, maladaptive behavior, renal tubular dysfunction, vitamin-D-resistant rickets, and scoliosis. The underlying gene OCRL1 is located on chromosome Xq25-q26 and contains 24 exons. It encodes a 105-kDa phosphatidylinositol 4,5-bisphosphate (PtdIns[4,5]P(2)) 5-phosphatase that is localized to the Golgi complex. To confirm the clinical diagnosis and to assess the carrier state of female relatives for genetic counseling we examined 6 independent patients and their families (a total of 23 individuals) using an improved mutation screening strategy for the OCRL1 gene by sequencing of large PCR amplicons. Four novel and two known mutations were identified: three premature terminations caused by either frameshift mutations (1899insT in exon 17 and 2104-2105delGT in exon 18) or a nonsense mutation (1399C > T in exon 12), two missense mutations (1676G > A and 1754C > T in exon 15), and a 6-bp deletion (1609-1614delAAGTAT in exon 14). An ophthalmological examination was performed in all patients and 14 female relatives. All genotypically proven carrier females showed characteristic lenticular opacities, while all proven noncarriers were lacking this phenotypic finding. The results confirm that ophthalmological evaluation is an apparently reliable first-line method to ascertain the carrier state in Lowe oculocerebrorenal syndrome. The high expressivity of lenticular symptoms in OCRL1 gene carriers is consistent with the hypothesis that (PtdIns[4,5]P(2)) 5-phosphatase activity has low functional reserve capacity for maintaining a balanced homeostasis of lenticular metabolism.

Adolescent↗
PubMed2000

[Transnasal anchor suture for facilitating silicone tube intubation in deep congenital nasolacrimal duct stenosis].

BACKGROUND: In silicone intubation of the nasolacrimal duct for congenital obstruction, retrieval of the guide thread behind the inferior turbinate can be difficult and time consuming. To facilitate this maneuver a modification of the conventional technique has been developed. PATIENTS AND METHOD: In the conventional technique, a hollow probe was inserted into both lacrimal puncti and pushed downward into the nasal cavity. A guide thread was forwarded into the pharynx. Using the same hollow probe, a third guide thread was inserted transnasally and also forwarded into the pharynx. These three threads were pulled out of the pharynx transorally and tied together. Pulling on the nasal aspect of the transnasal guide brought all guides back into the pharynx and out of the nose. The intubation was completed in the conventional way. RESULTS: The new method was evaluated in 13 children. With the conventional technique the mean duration of the operation was 35 min, but the time required varied greatly among individuals due to retrieval of the guides. In contrast, no guide retrieval problem occurred using the new technique, and the average duration was reduced to 25 min. No adverse effect was observed. CONCLUSION: Using a simple modification, difficulties with the retrieval of the guide thread could be avoided, thus facilitating the procedure of nasolacrimal duct intubation and reducing its duration.

Child↗
PubMed2000

Mutations in the VMD2 gene are associated with juvenile-onset vitelliform macular dystrophy (Best disease) and adult vitelliform macular dystrophy but not age-related macular degeneration.

Recently, the VMD2 gene has been identified as the causative gene in juvenile-onset vitelliform macular dystrophy (Best disease), a central retinopathy primarily characterised by an impaired function of the retinal pigment epithelium. In this study we have further characterised the spectrum of VMD2 mutations in a series of 41 unrelated Best disease patients. Furthermore we expanded our analysis to include 32 unrelated patients with adult vitelliform macular dystrophy (AVMD) and 200 patients with age-related macular degeneration (AMD). Both AVMD and AMD share some phenotypic features with Best disease such as abnormal subretinal accumulation of lipofuscin material, progressive geographic atrophy and choroidal neovascularisation, and may be the consequence of a common pathogenic mechanism. In total, we have identified 23 distinct disease-associated mutations in Best disease and four different mutations in AVMD. Two of the mutations found in the AVMD patients were also seen in Best disease suggesting a considerable overlap in the aetiology of these two disorders. There were no mutations found in the AMD group. In addition, four frequent intragenic polymorphisms did not reveal allelic association of the VMD2 locus with AMD. These data exclude a direct role of VMD2 in the predisposition to AMD.

Adolescent↗
PubMed2000

Comitant strabismus.

A review of the literature on comitant strabismus of the period from April 1999 until April 2000 is presented. A rather new and increasingly important issue is the psychosocial aspect of strabismus. Two studies have demonstrated that strabismus creates a significant negative social prejudice on the patients and that it can significantly reduce an applicant's ability to obtain employment. Subsequently, strabismus surgery can no longer be called "cosmetic". Concerning the timing of surgery in congenital esotropia, it was reported that early surgery does not ensure continued alignment, but frequently requires additional operations. The increased risk of early-onset strabismus in prematurely born children was confirmed by several studies, and the importance of regular ophthalmologic controls of all preterm infants screened for retinopathy of prematurity was stressed. It was reported that risk factors are cicatricial retinopathy of prematurity, refractive error, family history of strabismus, and poor neurodevelopmental outcome, rather than low gestational age and regressed acute retinopathy of prematurity. A number of other aspects of interest concerning exotropia, esotropia, and dissociated vertical deviation are presented in this review.

Anti-Dyskinesia Agents↗
PubMed2000

Effect of alcohol and light on the retinal pigment epithelium of normal subjects and patients with retinal dystrophies.

BACKGROUND: Light absorbed by photoreceptors causes oscillations in the voltage across the retinal pigment epithelium (RPE). This is the basis of the clinical test, electro-oculography (EOG). We have previously shown that alcohol causes a sequence of voltage changes which are so precisely the same as those caused by light that they must be produced by the same RPE machinery. There is good evidence that alcohol produces its effect by a direct action on the RPE. Consequently, in diseases associated with loss of photoreceptors, alcohol should continue to produce the voltage changes of the EOG unless secondary changes have occurred in the RPE. METHODS: The alcohol response in patients with retinitis pigmentosa (RP) was investigated using EOG. RESULTS: In no patient with RP was there any alcohol rise. CONCLUSION: In patients with RP secondary abnormalities of function of the RPE must occur.

Adult↗
PubMed1999

Effects of refractive blur on the multifocal electroretinogram.

A significant difference in the response density of the MF-ERG response has been suggested for every 2 diopter change of refraction. The influence of refractive blur on the MF-ERG was studied in 8 healthy volunteers using either the VERISTM system (Group A: n=5) or Retiscan(TM) (Group B: n=3). For each eye recordings were obtained with a corrective lens of -3 dpt, 0 dpt, +3 dpt and +6 dpt placed in front of the contact lens electrode. The viewing distance was adjusted to compensate for the induced changes in the retinal image size. When the changes in retinal image size due to the refractive lens were compensated for, no influence due to refraction was observed in either latencies or amplitudes of (KI (P > 0.05). This held true for the central response average (four degrees) as well as for the outer 6-25 degrees. In KII.1 only the peripheral amplitudes of Group B showed an influence due to refraction (P < or = 0.05). This may be due to adaptation as the recordings of group B were obtained in succession. As expected, significant differences were observed when the recordings obtained with the different systems were compared (P < or = 0.05).

Accommodation, Ocular↗
PubMed1999

Influence of cholestasis on absorption of ursodeoxycholic acid.

Ursodeoxycholic acid (UDCA) has beneficial effects in cholestatic liver diseases. Absorption of UDCA is slow and incomplete. In the present study the effect of cholestasis on absorption was evaluated in 10 patients with pancreatic carcinoma and extrahepatic biliary drainage. At days 3 and 10 after insertion of the biliary drain, all patients received 750 mg UDCA in three divided doses. On both occasions intestinal absorption of UDCA was determined to evaluate the influence of cholestasis. Serum bilirubin was used as indicator of cholestasis. Biliary output of UDCA served as measure of absorption and was determined by gas-liquid chromatography. At days 4 and 11 bile consisted of less than 2% of UDCA, indicating that UDCA excretion was complete within 24 hr and no accumulation of UDCA had occurred. After insertion of the drain, serum bilirubin decreased from 12.2 +/- 2.4 mg/dl at day 3 to 5.4 +/- 0.9 mg/dl at day 10. Biliary secretion of bile acids increased from 2.0 +/- 0.3 to 3.1 +/- 0.4 mmol/day, whereas percentage of ursodeoxycholic acid in bile did not significantly increase (41.1% vs 42.1%). Absorption of UDCA increased from 39.8 +/- 5.0% to 61.1 +/- 6.2% of the administered dose, indicating an improvement of the absorption rate after decrease of cholestasis by 53.65% (P < 0.05). In conclusion, in severe cholestasis absorption of orally administered UDCA is markedly reduced. This may have implications in the treatment of patients with cholestatic disease.

Administration, Oral↗
PubMed1999

[Color vision in relation to age: a study of normal values].

BACKGROUND: It is difficult to quantify thresholds in most colour vision tests, and this is especially the case for tritan hues, where a strong age-related increase of threshold has been reported. With the development of computer-graphic methods it is possible to remove brightness clues caused by lens absorption. This study attempts to give normative values for colour contrast thresholds and assess the age related changes therein. PATIENTS AND METHODS: 115 patients aged between 6 & 71 years were tested for central and peripheral colour contrast sensitivity. No patient had any systemic or eye disease. As a preliminary, heterochromatic flicker balance between the luminosities of the R and G and B and G phosphors was established, so that all colours subsequently generated were isoluminant for the person tested. Then, using a modified binary search technique, colour contrast thresholds were established using both 2 degree optotypes, for central vision, and a ring, 12.5 degrees in radius for peripheral vision. In the latter case, the observer had to name the position of the missing quadrant in the ring. Stimuli were presented for 200 msec at 1 Hz. Colours were modulated on protan, deutan or tritan colour axis. RESULTS: No correlation between age and central colour vision thresholds was observed. By contrast a significant but only minor increase of peripheral colour vision threshold was observed for the peripheral protan and tritan axis. DISCUSSION: The present system removes luminance clues from colour vision tests and permits both central and peripheral retina to be tested. The results are simple in that the influence of age can be neglected. The variability of threshold results is small, and it is easy to detect the relatively large changes associated with disease. Since high-quality monitors are standardised and calibrated, providing the stimulus parameters described are adhered to, the results given here for upper limits of normal may be used for other similar systems.

Adolescent↗
PubMed1998

[North Carolina macular dystrophy. Hereditary macular disease with good functional prognosis].

BACKGROUND: North Carolina macular dystrophy (NCMD) is a rare autosomal dominant maculopathy with highly variable expressivity. Genetic analysis of an American family consisting of 247 members out of which 96 were affected with NCMD allowed chromosomal assignment of the NCMD locus to 6q14-q16.2. Few families with NCMD are known in Europe, one of these is living in Germany. By routine investigation, a second family affected with NCMD was detected in Germany. As some authors still doubt the good prognosis of this disease, our results should be added to the experience of others. PATIENTS AND METHODS: In a total of 18 family members from three generations between the age of 2 and 65 years, clinical investigations and genetic analysis was carried out. Some individuals had additional examinations such as colour contrast sensitivity, EOG, ERG, and microperimetry. RESULTS: Ten of 18 family members turned out to be affected. All grades of NCMD were present with great variability. Visual acuity ranged from 0.32 to 1.0 and did not correlate to the grade of the disease or to the age of the person. In those patients who underwent microperimetry, central fixation was confirmed. Genetic linkage analysis further narrowed the region harbouring the NCMD locus and supported the assumption that the central areolar pigment epithelial dystrophy (CAPED) is an allelic disorder. CONCLUSION: Similar visual acuity in three generations of NCMD patients supports the observation that NCMD is not a progressive disorder. If geographic atrophy is found in a patient with good visual acuity, NCMD should be considered and genetic analysis should be carried out.

Adolescent↗