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H D Schworm

Publications and source records attributed to H D Schworm.

At least 19 recordsLinked to original sources
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↗
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

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

Interleukin-1 receptor antagonist ribonucleic acid and protein expression by cultured Graves' and normal orbital fibroblasts is differentially modulated by dexamethasone and irradiation.

Recent data have indicated that orbital fibroblasts (OF) can be stimulated to produce marked quantities of interleukin-1 receptor antagonist (IL-1RA), a powerful inhibitor of the proinflammatory activities of interleukin-1 in the orbital tissues in Graves' ophthalmopathy (GO). We examined whether the beneficial effects of dexamethasone or irradiation, the two main therapeutic modalities applied in patients with active GO, may be related to their capacity to alter IL-1RA ribonucleic acid (RNA) and protein expression in OF. Early passages of cultured OF were obtained from orbital connective tissue and extraocular muscle of patients with severe active GO and five control subjects. Modulation of the two variants of IL-1RA, intracellular IL-1RA (icIL-1RA) and soluble IL-1RA (sIL-1RA), was studied after exposure of OF to increasing concentrations of dexamethasone (10(-10)-(10(-6) mol/L)), the glucocorticoid receptor antagonist RU 38486 (10(-3) mol/L), or combinations thereof. Alternatively, cell monolayers were exposed to increasing doses of UV irradiation (0.1-1 J/cm2) or ionizing irradiation (0.2-2 Gy). The IL-1RA gene and protein variants were analyzed by RT-PCR, immunocytochemistry, immunoblotting, and enzyme-linked immunosorbent assay. Dexamethasone inhibited IL-1RA RNA steady state levels in GO OF and control OF in a dose-dependent manner. Combined exposure of OF to dexamethasone and RU 38486 completely restored baseline levels of IL-1RA RNA. By contrast, low doses of UV and ionizing irradiation dose dependently up-regulated IL-1RA-specific transcripts in GO OF and control OF, whereas higher doses were less effective. Immunoblotting and enzyme-linked immunosorbent assay revealed suppression of IL-1RA immunoreactivity after treatment with dexamethasone and enhanced expression of IL-1RA by GO OF and normal OF after low doses of UV and ionizing irradiation. Our results indicate that, in contrast to dexamethasone, low doses of irradiation stimulate expression of the IL-1RA gene and protein variants in OF. Induction by irradiation of IL-1RA expression in target cells of the orbital immune process represents an as yet unrecognized mechanism by which orbital radiotherapy may exert some of its beneficial therapeutic effects in patients with active GO.

Cells, Cultured↗
PubMed2000

Clinical significance of saccade analysis in early active Graves' ophthalmopathy.

PURPOSE: To assess whether saccadic eye movements show distinct changes in patients with early active Graves' ophthalmopathy (GO), which could serve as a diagnostic tool for early detection and treatment. METHODS: Each of two prospective studies included 10 patients with early acute GO and 10 age- and sex-matched control subjects. In the explorative study (ES) 15 dynamic parameters of saccades were analyzed. In the comparative study (CS) only those parameters were evaluated, which in ES had shown significant differences between patients and controls. Horizontal and vertical saccades of 10 degrees, 20 degrees, and 40 degrees including a fatigue test were recorded binocularly using the induction scleral search coil. RESULTS: The differences of saccadic dynamics between patients and controls were small, whereas intra- and interindividual standard deviations were large. In ES, 7.1% of the parameters showed significant differences at a level of P < or = 0.05. In CS, 2.1% of all parameters revealed repetitive significant differences. Despite statistical significance, individual data did not allow differentiation between patients and healthy individuals due to high standard deviations. CONCLUSIONS: In early active GO no clinically relevant saccadic changes were detected. These findings may be based on adaptation of the central saccadic generator. Inclusion of patients with fibrotic muscle changes due to long-standing disease could explain the contrasting results of previous studies. Consequently, analysis of saccades does not serve as a diagnostic tool during early active GO.

Acute Disease↗
PubMed2000

Preliminary report: saccade analysis in acute Graves' ophthalmopathy.

A prospective study on the saccadic properties of 10 patients with acute Graves' ophthalmopathy (GO) compared to 10 healthy individuals was performed using the induction scleral search coil. No significant changes were observed among six patients with moderate disease. In four patients suffering from optic nerve compression, however, a substantial decrease of saccadic velocity and related parameters was detected. The absence of saccadic changes in earlier moderate stages of GO seems to be based on adaptation of the central saccadic generator. The velocity reduction in connection with a marked elevation of intraorbital pressure could be indicative of paretic motoneuron disturbances.

Acute Disease↗
PubMed1999

[Exophthalmos--what now?].

Exophthalmos is most commonly due to Graves' ophthalmopathy (GO), the most frequent extrathyroidal manifestation of Graves' disease. The clinical signs and symptoms of GO are the consequences of increased orbital connective and adipose tissue volume, and of interstitial enlargement of extraocular muscles, within the confines of the bony orbits. Diagnosis of GO is usually readily established by obtaining a careful history, detailed clinical examination of the thyroid gland, eyes and orbits, few laboratory tests and ultrasonography of the thyroid gland and the orbital contents. Additional procedures such as computed tomography or magnetic resonance imaging are rarely needed. A team approach (general practitioner, endocrinologist, ophthalmologist) is essential to assure state-of-the-art management of patients with GO, and to properly select the best choices from a still limited range of therapeutic options.

Anti-Inflammatory Agents↗
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↗
PubMed1998

[Changes in subjective cyclodeviation and objective cycloposition after modified Harada-Ito operation in acquired trochlear paralysis].

BACKGROUND: After recently published own investigations on subjective and objective cyclorotatory changes following inferior oblique recession for inferior oblique overaction, it was our aim to determine and to compare subjective and objective cyclorotatory changes following a modified Harada-Ito procedure for acquired trochlear palsy. PATIENTS AND METHODS: Eight patients suffering from acquired uni-(n = 3) or bilateral (n = 5) trochlear palsy were investigated before surgery and 1 day, 3 days and 4 months after surgery. Subjective cyclodeviation was assessed by Harms' tangent scale. Objective cycloposition was measured by means of fundus cyclometry using an infrared Scanning Laser Ophthalmoscope. RESULTS: The immediate postoperative incyclorotatory effect was 12 degrees in the unilateral group and 18 degrees in the bilateral group. Subjective and objective changes were nearly equal in both groups, with a subjective over-effect of 1 degree. After two days of binocular stimulation a marked regression of the surgical effect was found which still increased after four months. The long term incyclorotatory effect was subjectively and objectively nearly equal in the unilateral group which showed a relaps of subjective excyclodeviation of 5 degrees: in the bilateral group, the subjective effect was more pronounced than the objective effect, the immediate postoperative over-effect being disappeared. CONCLUSIONS: In contrast to our results concerning inferior oblique muscle recession for strabismus sursoadductorius, subjective and objective cyclorotatory changes did not differ grossly following a modified Harada-Ito procedure. Subjective and objective short and long term regression was confirmed which objectively exceeded the amount of over-correction. As the underlying cause mechanical and sensory mechanisms are discussed.

Adult↗
PubMed1997

[Endocrinologic and metabolic complications of Alagille syndrome].

BACKGROUND: Patients with gastrointestinal and hepatobiliary disorders, either congenital or acquired early in childhood, are at high risk for various endocrine and metabolic abnormalities. CASE REPORT: A 27-year-old woman with Alagille's syndrome presented with progressive jaundice and gait disturbances following surgery and ingestion of oral contraceptives. On physical examination, short stature, facial dysmorphism and neuromuscular symptoms such as polyneuropathy and spinocerebellar ataxia were noted. Serum concentrations of total bilirubin (54 mg/dl) and alkaline phosphatase were markedly increased, whereas serum levels of haptoglobin, zinc, vitamin D and E were decreased. Although prehepatic or intrahepatic etiologies of jaundice were more likely in this patient, posthepatic etiologies were ruled out by abdominal ultrasound and endoscopic retrograde cholangio-pancreaticography. Based on a working diagnosis of acute drug-induced cholestasis, treatment with high doses of lipid-soluble vitamins and ursodeoxycholic acid was initiated. In response to therapy, her abnormal laboratory results normalized and her neurologic symptoms markedly improved. CONCLUSION: This clinicopathological conference of a patient with Alagille's syndrome illustrates the clinical presentation and therapy of metabolic and endocrine complications in chronic cholestasis.

Adult↗
PubMed1997

[Measuring saccades in endocrine orbitopathy].

Thyroid-associated ophthalmopathy (TAO) is evaluated mainly by orthoptic examination and morphometric parameters such as ultrasound, CT scanning or magnetic resonance imaging. Inflammatory changes of the extraocular muscles lead to an impairment of eye movement. Recent evidence suggests that saccades are altered by changes to the extraocular muscles. Although of potential interest, this phenomenon has so far received little attention. To determine the role of saccades as a potential diagnostic tool for assessing the function of the affected muscles, we have begun to analyze saccadic parameters in patients with TAO. Preliminary results of this study are reported in the present paper. For registration of both horizontal and vertical eye movements, we used the "Ober-2-Apparatus," which uses the infrared technique. Horizontal and vertical saccades with an amplitude of 10 degrees were analyzed in 20 healthy persons and 30 patients suffering from TAO. Patients showed changes in the quality of saccades, such as the appearance of glissades and additional correctional saccades as well as quantitative changes, such as an increase in the maximum speed and latency. Our current data suggest the presence of saccadic alterations in TAO. Our ongoing studies are designed to evaluate whether characteristic changes can be assigned to certain stages of the disease and whether assessment of saccadic changes in a promising tool for early detection and functional follow-up in patients with TAO.

Adult↗
PubMed1997

[Functional eye muscle changes in endocrine orbitopathy].

BACKGROUND: To determine the functional changes in the extraocular muscles in patients with thyroid-associated ophthalmopathy (TAO). PATIENTS AND METHODS: Horizontal saccades with an amplitude of 20 degrees were carried out over a period of 2 min. Eight patients with acute TAO and five patients with chronic TAO were compared with ten age-matched healthy individuals. Ocular movements were recorded using the "Ober 2" system based on infrared technology. For evaluation of fatigue effects, the parameters of the first five and the last five saccades were analysed. RESULTS: A significant difference of four and five, respectively, out of nine tested saccadic variables including maximum velocity (Vmax) was found both before and after fatigue. In comparison to normal subjects, patients with chronic TAO revealed mildly increased reduction of Vmax after fatigue. Results in patients with acute TAO were related to the action of the most severely affected muscle. On active contraction of the medial rectus muscle (adducting saccades), Vmax was not significantly decreased after fatigue. On passive elongation of the medial rectus muscle (abducting saccades), however, Vmax was initially markedly decreased and increased significantly after fatigue. CONCLUSIONS: Functional changes of extraocular muscles in patients with TAO can be demonstrated by saccadic analysis. The inverse change in velocity after fatigue in acute disease indicates an improvement of muscle elasticity during exertion and strongly supports the concept that early impairment of bulbar motility in active TAO results from contracture of myofilaments. Thus, analysis of the fatigue effect may help to differentiate between acute and chronic disease.

Graves Disease↗
PubMed1997

[Photoscreening for early detection of amblyogenic eye changes].

BACKGROUND: Congenital and early acquired ocular changes impairing the optic input induce amblyopia when left untreated. Amblyopia treatment must start early to be efficient. Therefore it seems necessary to employ screening tests in preverbal childhood. PATIENTS AND METHODS: The reliability of two commercially available photoscreening devices, the "Visiscreen 100" (Vision Research Corp.) and the "MTI-Photoscreener" (Medical Technology Inc.), was tested. 180 children from a kinder-garten and 120 infants from our outpatient clinic were screened. The results were compared to the findings of a full ophthalmologic and orthoptic examination. RESULTS: The efficacy of the photoscreening depended on the skill of the examiner and on the age of the children tested. The rate of interpretable photographs was 94% in the older group and 63.3% in the infants. The mean sensitivity for detection of amblyogenic factors was 63% in the older and 80% in the infant group. The mean negative predictive value was 90%, and 75%, respectively. CONCLUSION: Modern photoscreening techniques can help to detect amblyogenic factors in early childhood. However, in addition to the non-interpretable photographs, about 20% of the affected children are missed. Therefore, photoscreening cannot be recommended for countries with a high number of ophthalmologists, such as Germany. Instead, an ophthalmologic and orthoptic investigation in early childhood would be preferable.

Amblyopia↗
PubMed1997

[Dural carotid-cavernous sinus fistulas: clinical aspects, diagnosis and therapeutic intervention].

BACKGROUND: Carotid cavernous fistulas are cerebral artenovenous shunts which may present with ocular or orbital signs. Direct fistulas are distinguished from dural shunts with respect to the anatomical situation. PATIENTS: We report on two patients with spontaneous dural carotid cavernous fistulas with multiple feeding vessels. Both patients required endovascular embolization. RESULTS: Therapy was successful in both patients. We present an overview of the clinical picture, the diagnostic procedure, the differential diagnosis and the therapeutic possibilities in this clinical entity. CONCLUSION: Both patients prove the importance of an immediate differential diagnostical classification so that a specific neuroradiological diagnostic can be ensured. Today's advanced endovascular technology offers therapeutic options with less risk for the patient than in recent years.

Arteriovenous Fistula↗
PubMed1997

An ancestral core haplotype defines the critical region harbouring the North Carolina macular dystrophy gene (MCDR1).

Autosomal dominant North Carolina macular dystrophy (NCMD) or central areolar pigment epithelial dystrophy (CAPED) is an allelic disorder that maps to an approximately 7.2 cM interval between DNA markers at D6S424 and D6S1671 on 6q14-q16.2. The further refinement of the disease locus has been hindered by the lack of additional recombination events involving the critical region. In this study, we have identified three multigeneration families of German descent who express the NCMD phenotype. Genotyping was carried out with a series of markers spanning approximately 53 cM around the NCMD locus, MCDR1. Genetic linkage between the markers and the disease phenotype in each of the families could be shown. Disease associated haplotypes were constructed and provide evidence for an ancestral founder for the German NCMD families. This haplotype analysis suggests that a 4.0 cM interval flanked by markers at D6S249 and D6S475 harbours the gene causing NCMD, facilitating further positional cloning approaches.

Chromosomes, Human, Pair 6↗
PubMed1997

Soluble interleukin-1 receptor antagonist serum levels in smokers and nonsmokers with Graves' ophthalmopathy undergoing orbital radiotherapy.

Interleukin-1 (IL-1) plays an important role in the pathogenesis of Graves' ophthalmopathy (GO). Impaired antagonism of the proinflammatory cytokine IL-1 by the naturally occurring IL-1 receptor antagonist (IL-1RA) has been implicated in the initiation and perpetuation of various autoimmune diseases and may play a role in the evolution of GO. Cigarette smoking appears to adversely affect the course of GO. We have evaluated the course of IL-1 alpha, IL-1 beta, and soluble IL-1RA (sIL-1RA) serum levels in smokers and nonsmokers with GO undergoing orbital radiotherapy (OR). We prospectively studied the eye status of 27 randomly selected patients (mean age 47.3 +/- 11.0 yr; 20 females; 18 smokers) with active, moderately severe GO before and 3 and 6 months following OR, respectively. None had received any previous treatment for GO, and all patients were kept euthyroid on carbimazole. Serum concentrations of IL-1 alpha, IL-1 beta, and sIL-1RA were measured using highly sensitive enzyme linked immunosorbent assay systems. Baseline sIL-1RA levels were negatively correlated with the number of cigarettes smoked before and following OR (P < 0.0001). Patients with no or minor therapeutic response to OR (n = 8), all of whom were smokers, revealed mean baseline sIL-1RA levels of 114 +/- 85 pg/mL, which increased to 172 +/- 103 pg/mL at 3 months and 149 +/- 96 pg/mL at 6 months after initiation of OR, respectively. By contrast, patients with a good clinical response (n = 19, 9 nonsmokers), revealed significantly higher baseline sIL-1RA levels at 294 +/- 148 pg/mL (P = 0.004), which increased to 845 +/- 668 pg/mL at 3 months (P = 0.01) and 634 +/- 337 pg/mL at 6 months (P < 0.001), respectively, following initiation of OR. Serum concentrations of IL-1 alpha IL-1 beta were below 3.9 pg/mL in all patients with GO who were studied, and were not correlated with gender, age, smoking status, clinical course, or outcome. Low baseline levels and impaired surge of sIL-1RA serum levels following OR were strongly correlated with smoking status and a less favorable therapeutic outcome in patients with active, moderately severe GO. Measurement of sIL-1RA may contribute to predict the therapeutic response to OR in patients with active, moderately severe GO. Strategies designed to raise local or systemic concentrations of sIL-1RA may be of benefit to patients with GO.

Adult↗
PubMed1997

Investigations on subjective and objective cyclorotatory changes after inferior oblique muscle recession.

PURPOSE: To determine subjective and objective cyclorotatory changes after surgery for oblique muscle disorders and to analyze the mechanisms of the well-known, long-term, postoperative, subjective cyclotorsional changes. METHODS: Twenty-six patients underwent unilateral inferior oblique muscle recession for strabismus sursoadductorius (inferior oblique overfunction). Subjective and objective cyclodeviation were examined before surgery with and without diagnostic occlusion, as well as 1 day, 3 days, and 4 months after surgery. Subjective cyclodeviation was assessed by Harms' tangent scale. Objective cycloposition was measured by means of fundus cyclometry, a novel method using an infrared scanning laser ophthalmoscope. RESULTS: Diagnostic occlusion did not lead to significant changes in either objective or subjective cyclodeviation. Preoperative objective excycloposition was nearly equally distributed between affected eyes and fellow eyes. Early surgically induced incyclorotatory effects were more pronounced objectively than subjectively. On long-term follow-up, a reduction in the incyclorotatory effect was found to be smaller subjectively than objectively. A significant difference between subjective and objective cycloposition was seen early after surgery, and a significant difference between subjective and objective cyclorotatory change was found immediately after surgery and on long-term follow-up. CONCLUSIONS: Long-term regression of the incyclorotatory effect after inferior oblique muscle recession was confirmed objectively and subjectively and can be explained as a cessation of preoperatively required binocular compensatory innervation. The authors conclude that the difference between objective and subjective regression is caused by sensory cyclofusion.

Adolescent↗