Disturbances of binocular vision in macular heterotopia]

BACKGROUND: Tractive translocation of the macula (secondary macular heterotopia) may result in disturbance of binocular vision. The report of a case shall discuss the sensorial problems of these patients. HISTORY AND SIGNS: We report of a 40-years old male who had decreased visual acuity and loss of binocular vision for several years due to episodes of uveitis with intravitreous hemorrhage and cataract formation. After bilateral vitrectomy and cataract extraction a good visual acuity was restored in both eyes. Postoperatively, the patient monocularly complained about disturbed egocentric localization (tilting of the visual environment, "past-pointing") and metamorphopsia. Binocularly he was confused by doubled vision with tilted images. Both maculae showed a tractive translocation of 15 degrees downward. Measurements of binocular alignment with the tangent screen showed an excyclotropia of 8 degrees and an exotropia of 7 degrees in all directions of gaze. Haploscopic examination with fusion images demonstrated that sensorial fusion was not possible even with perfect ocular alignment due to disturbed relative retinal localization (obligate fixation disparity). THERAPY AND OUTCOME: Initially, full time occlusion of the left eye was required. After improvement of symptoms occlusion therapy was slowly tapered. Within one year the patient had learned to suppress the image of his left eye and reported only minor residual visual disturbances even without occlusion of his left eye. CONCLUSIONS: Secondary translocation of the macula monocularly results in a disturbance of egocentric localization and in metamorphopsia. Binocularly doubled vision with tilted images and a loss of sensorial fusion are seen. With monocular vision, perceptual adapting to the aberration in egocentric localisation is possible within weeks by reallocation of the retinal meridians in the central nervous system. Binocular improvement of symptoms is limited to the learning of suppression. Improvement of binocular symptoms by adaptation of retinal correspondence does not occur.     

Management of acute submacular hemorrhage using recombinant tissue plasminogen activator and gas

· Purpose: To assess the effects of intravitreal injection of recombinant tissue plasminogen activator (rTPA) and gas on submacular hemorrhage in age-related macular degeneration (ARMD). · Methods: Eleven consecutive patients (11 eyes) with subretinal hemorrhage due to ARMD involving the fovea with elevation of the neurosensory retina were included in this study. Subretinal hemorrhage occured 12 h to 14 days before onset of therapy. Injection of rTPA through the pars plana in a dose of 50 or 100 μg was performed. Gas instillation (0.2–0.4 ml) followed rTPA injection, either immediately after injection (7 patients) or during the following day (4 patients). · Results: After intravitreal injection of rTPA, subretinal clots were totally or partially liquefied when treatment started up to 3 days after onset of bleeding. In all patients treated with 100 μg rTPA a large exudative retinal detachment of the inferior retina resulted, which reabsorbed spontaneously within 2 weeks. After reattachment of the exudative retinal detachment hyperpigmentation of the retinal pigment epithelium was noted. Temporary opacification of the vitreous was observed between the 2nd and 7th postoperative day in 5 eyes (45.5%). Postoperative visual acuity increased in 5 patients (45.5%). · Conclusion: Intravitreal application of rTPA followed by gas injection is a sufficient and convenient technique for effective removal of freshly formed submacular hemorrhage. Removal is mediated through combined enzymatic (rTPA) and mechanical (gas) effects. This technique offers a quick recovery of vision in eyes with less severe ARMD. Received: 5 January 1998 Revised version received: 25 March 1998 Accepted: 23 June 1998     

Randomized trial of radiation for age-related macular degeneration.

PURPOSE: To assess external beam radiation efficacy for subfoveal neovascularization associated with age-related macular degeneration. METHODS: All patients were evaluated in the same institution. In this prospective trial, 27 eyes (27 patients) with subfoveal neovascularization associated with age-related macular degeneration were randomized to either single fraction radiation (750 centigray) or observation. Endpoints were assessed by fluorescein angiography and Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity. Examiners were masked to patient treatment status. Parametric and nonparametric statistical analyses were performed. RESULTS: Twenty-seven patients were entered into the trial with a mean age of 76 years (range, 64 to 89) and a mean follow-up of 17 months (range, 7 to 32). The visual acuity loss was slightly less in the irradiated group, a finding of borderline significance (P < .046). There was no significant difference in fluorescein angiographic evidence of subretinal neovascular membrane change in the control group vs the irradiated group. CONCLUSIONS: External beam radiation, at this dose and fractionation, did not appear harmful. There was slightly less visual loss in irradiated eyes. No difference in fluorescein angiographic characteristics of subfoveal neovascularization size or progression in eyes with age-related macular degeneration was noted.     

Abbreviated chemotherapy with fludarabine followed by tositumomab and iodine I 131 tositumomab for untreated follicular lymphoma.

PURPOSE: To evaluate the safety and efficacy of a sequential chemotherapy plus radioimmunotherapy (RIT) regimen in previously untreated follicular non-Hodgkin's lymphoma. PATIENTS AND METHODS: Thirty-five patients received an abbreviated course (three cycles) of fludarabine followed 6 to 8 weeks later by tositumomab and iodine I 131 tositumomab. RESULTS: After fludarabine, 31 (89%) of 35 patients responded, with three (9%) of 31 patients achieving a complete response (CR). After the full regimen of fludarabine and iodine I 131 tositumomab, all 35 patients responded; 30 (86%) of 35 patients achieved CR, and five (14%) of 35 achieved partial response. After a median follow-up of 58 months, the median progression-free survival (PFS) had not been reached (95% CI, 27 months to not reached), but it will be at least 48 months. The 5-year estimated PFS rate is 60%. Baseline Follicular Lymphoma International Prognostic Index (FLIPI) was significantly associated (P = .003) with PFS. Five of six patients with more than 25% bone marrow involvement at baseline achieved adequate bone marrow cytoreduction to receive standard-dose iodine I 131 tositumomab. Ten (77%) of 13 patients with baseline bone marrow Bcl-2 positivity demonstrated molecular remissions at month 12. Toxicities were manageable and principally hematologic. Two (6%) of 35 patients developed human antimurine antibodies (HAMA) after RIT. CONCLUSION: Use of abbreviated fludarabine before iodine I 131 tositumomab can reduce bone marrow involvement, when needed, to allow the use of RIT and can suppress HAMA responses. This sequential treatment regimen is highly effective as front-line therapy for follicular lymphoma, particularly for low- or intermediate-risk FLIPI patients.     

A positron emission tomography study of silent and oral single word reading in stuttering and nonstuttering adults.

Over the last decade positron emission tomography (PET) has been used extensively for the study of language and other cognitive and sensorimotor processes in healthy and diseased individuals. In the present study, [15O]H2O PET scanning was used to investigate the lateralization and functional distribution of cortical and subcortical activity involved in single word reading in stuttering and nonstuttering individuals. Ten right-handed male stuttering adults and matched nonstuttering individuals were instructed to read individually presented single words either silently or out loud. Subtraction of functional brain images obtained during each of the two reading tasks, and during a non-linguistic baseline task, was used to calculate within-group and between-group differences in regional cerebral blood flow by means of statistical parametric mapping. Increased activation in the left anterior cingulate cortex (ACC) was observed during silent reading in the stuttering speakers but not in the nonstuttering group. Because of the hypothesized role of the ACC in selective attention and covert articulatory practice, it is suggested that the observed increased ACC activation in the stuttering individuals reflects the presence of cognitive anticipatory reactions related to stuttering. During the oral reading task, within-group comparisons showed bilateral cortical and subcortical activation in both the stuttering and the nonstuttering speakers. Between-group comparisons showed a proportionally greater left hemisphere activation in the nonstuttering speakers, and a proportionally greater right hemisphere activation in the stuttering individuals. The results of the present study provide qualified support for the hypothesis that stuttering adults show atypical lateralization of language processes.     

Type b capsular polysaccharide as a virulence factor of Haemophilus influenzae

The capsular polysaccharide of Haemophilus influenzae serotype b [(3)-beta-D-ribose-(1-1)-ribitol-5-phosphate] is a major virulence factor and a target for serum antibodies which protect individuals against invasive infections. Studies in an experimental rat model of meningitis, using genetically defined H. influenzae transformants, provide evidence that chromosomal genes within or limited to a region (cap b) containing genes necessary for type b capsule are critical for efficient intravascular survival of H. influenzae. Within cap b there is a duplication of a 17 kb region organized as direct repeats separated by a smaller (1-2 kb) region of non-repeated DNA. Homologous recombination between the direct repeats is rec dependent and results in high-frequency loss of capsule expression and virulence.     

Antigen-positive platelet transfusion in neonatal alloimmune thrombocytopenia (NAIT)

Neonatal alloimmune thrombocytopenia (NAIT) is a fetomaternal incompatibility most commonly induced by maternal anti-HPA-1a, IgG alloantibodies against a polymorphic epitope of the glycoprotein IIb/IIIa complex in approximately 97.5% of white patients. Current guidelines recommend transfusion of immunologically compatible platelets to prevent cerebral hemorrhage, the most severe complication in affected newborns. Such platelet concentrates, however, are often not readily available. In a retrospective analysis in German and Canadian centers, 27 newborns with NAIT were identified who received platelets from random donors. Unexpectedly, 24 of 27 newborns showed an increase above a threshold of 40 x 10(9) platelets per liter, with moderate (n = 8) or significant (n = 16) platelet count increments (more than 80 x 10(9)/L). We conclude that transfusion of platelet concentrates from random donors is an appropriate strategy in the management of unexpected, severe NAIT predominantly in first pregnancies, pending the availability of compatible platelets.