[Retinovascular Findings in Susac's Syndrome]. / Retinovaskuläre Zeichen des Susac-Syndroms.

BACKGROUND: Susac syndrome is a vasculopathy affecting the central nervous system, retina and cochlea leading to the triad encephalopathy, branch retinal artery occlusions and hearing loss. To date, about 300 cases have been described in the literature. PATIENTS/METHODS: Three patients with confirmed Susac syndrome were evaluated for disease-specific retinal pathologies. In addition, the overall history of the disease is presented to put the ophthalmological pathology into context. RESULTS: All three cases showed a retinal occlusive microangiopathy with branch retinal artery occlusions. MRI imaging revealed snowball-like lesions of the corpus callosum in two of three cases. At the initial presentation not all criteria of the disease-specific triad encephalopathy, branch retinal artery occlusions, and hearing loss were fulfilled in the three patients. CONCLUSION: Interdisciplinary collaboration between neurologists, otorhinolaryngologists and ophthalmologists is mandatory to establish the diagnosis of the disease. The occurrence of the characteristic retinal pathology with small artery occlusions and a segmental vasculopathy should always lead to the differential diagnosis of Susac syndrome.

[Intermittent Exotropia]. / Intermittierende Exotropie.

Intermittent exotropia (IXT) is a congenital form of divergent strabismus. Its incidence is estimated to be 32 per 100 000. Most often, IXT is first noted in early childhood when intermittently manifest outward deviation of the eyes is seen. Patients with IXT can control the deviation and keep the eyes aligned; this ability can be measured with "control scores". Complications such as amblyopia and loss of binocular functions are rare but should be looked for and need to be avoided. IXT can have a negative impact on quality of life. Conservative treatment includes the correction of refractive errors, (alternating) occlusion, over-minus lenses and orthoptic exercises. By injecting an extraocular muscle with botulinum toxin (to weaken its function) or with bupivacaine (to strengthen its function), IXT can be treated pharmacologically. Diagnostic occlusion and prism adaptation are strategies to uncover the true (largest) angle. Eye muscle surgery aims at eliminating the condition, but recurrences are common. The literature on large, randomized prospective trials for IXT is scarce. However, there are trials underway in the United Kingdom and in North America to better understand the natural course of IXT and to determine the most appropriate therapeutic approach.

[Retinovascular findings in Susac's syndrome]. / Retinovaskuläre Zeichen des Susac-Syndroms.

BACKGROUND: Susac syndrome is a vasculopathy affecting the central nervous system, retina and cochlea leading to the triad encephalopathy, branch retinal artery occlusions and hearing loss. To date, about 300 cases have been described in the literature. PATIENTS/METHODS: Three patients with confirmed Susac syndrome were evaluated for disease-specific retinal pathologies. In addition, the overall history of the disease is presented to put the ophthalmological pathology into context. RESULTS: All three cases showed a retinal occlusive microangiopathy with branch retinal artery occlusions. MRI imaging revealed snowball-like lesions of the corpus callosum in two of three cases. At the initial presentation not all criteria of the disease-specific triad encephalopathy, branch retinal artery occlusions, and hearing loss were fulfilled in the three patients. CONCLUSION: Interdisciplinary collaboration between neurologists, otorhinolaryngologists and ophthalmologists is mandatory to establish the diagnosis of the disease. The occurrence of the characteristic retinal pathology with small artery occlusions and a segmental vasculopathy should always lead to the differential diagnosis of Susac syndrome.

[Ophthalmologic screening history and vision-targeted health status of patients suffering from chloroquine maculopathy]. / Screeninganamnese und sehkraftbezogene Lebensqualität von Patienten mit Chloroquin-Makulopathie.

BACKGROUND: Maculopathy or retinopathy can develop as a side effect of chloroquine intake. Despite recommendations for ophthalmologic screening by the American Academy of Ophthalmology (AAO) severe toxic retinal damage still occurs. This study aims to clarify how maculopathy affects patient quality of life and whether it arises only due to non-compliance with screening guidelines. METHODS: Patients suffering from chloroquine maculopathy were questioned about the ophthalmologic examinations that took place under therapy and completed a German version of the 25 item visual function questionnaire (VFQ-25). RESULTS: A total of ten female patients were included in the analysis. Weighted visual acuity ranged from 0.09 to 0.8. Median composite score of the VFQ-25 was 33.9. All patients were periodically screened for ocular toxicity with a median trimestrial screening frequency but five patients did not receive all recommended methods of examination. There was suspicion of retinal damage in only one patient even without the patient reporting complaints. Median time span between onset of visual complaints and the cessation of the drug was 12 months. All patients with complaints reported a continuing deterioration of vision even after cessation. CONCLUSIONS: Chloroquine maculopathy has a major impact on the vision-related health status of affected patients, emphasizing the need for its anticipation. Although patients were screened even more frequently than recommended by the AAO only half were examined properly and nine out of ten patients had a delay in diagnosis and in drug cessation. The continuing deterioration of vision even after termination of intake further contributes to the severity of the disease.

[Unusual presentation of a Langerhans cell histiocytosis]. / Ungewöhnliche Präsentation einer Langerhans-Zell-Histiozytose.

A 16-month-old male infant was presented with swelling of the left upper eye lid 4 weeks after a blunt orbital trauma. A prolonged hematoma was suspected and the child was discharged with an appointment 4 weeks later. However, the child was presented again with progressive swelling of the lid 10 days later. Magnetic resonance imaging (MRI) showed a tumor extending from the frontal bone to the anterior cranial fossa and into the orbit. An incisional biopsy led to the diagnosis of orbital Langerhans cell histiocytosis and systemic therapy led to complete remission of the tumor. Prolonged periorbital swelling must always prompt further diagnostics even when patients present with a history of trauma.

Evaluation of risk factors for retinal damage due to chloroquine and hydroxychloroquine.

BACKGROUND/AIMS: To evaluate risk factors for retinal damage due to the intake of chloroquine and hydroxychloroquine. METHODS: In a retrospective chart review, patients receiving or having received one of the drugs were classified as affected by maculopathy or retinopathy, or as not affected on the basis of the documented findings. Uncertain cases were excluded. The risk factors as postulated by the American Academy of Ophthalmology (AAO) and additional factors like diagnosis of underlying disease, total dose, nicotine abuse and the sum of the AAO risk factors were compared between both groups. RESULTS: 51 patients with a history of or ongoing treatment with chloroquine (23 individuals) or hydroxychloroquine (28 individuals) were included. Most of the postulated risk factors were expectedly elevated in the affected group. Significant differences applied to age, duration of intake and the sum of AAO risk factors. Surprisingly, positive smoking history was more frequent in the not affected. The toxic threshold of the daily chloroquine dose was exceeded by most of the patients. CONCLUSIONS: Age and the duration of intake are major risk factors. Smoking seems to be negligible. The sum of AAO risk factors can give an estimation of the individual risk profile. Individual and weight-adapted dosing is especially essential for chloroquine.

Fourier transformed steady-state flash evoked potentials for continuous monitoring of visual pathway function.

Monitoring of somatosensory, motor and auditory pathway function by evoked potentials is routine in surgery placing these pathways at risk. However, visual pathway function remains yet inaccessible to a reliable monitoring. For this study, a method of continuous recordings was developed and tested. Steady-state visual evoked potentials were elicited by flash stimulation at 16 Hz and analysed using discrete Fourier transform. Amplitude and phase of the fundamental response were dynamically averaged and continuously plotted in a trend graph. The method was applied on awake individuals with normal vision and on patients undergoing neurosurgery. In most individuals it was possible to continuously record significant responses. Surprisingly, characteristic time-courses of amplitude and phase were observed in several subjects. These findings were attributed mainly to flicker-adaptation. During anesthesia, amplitude and signal-to-noise ratio were markedly smaller. Signal recognition was facilitated when potentials were recorded with a subdural electrode placed directly at the occipital pole. The anesthetic agent propofol had a major impact on the recordings.