L eber hereditary optic neuropathy (LHON) is a form of blindness due to retinal ganglion cell dys... more L eber hereditary optic neuropathy (LHON) is a form of blindness due to retinal ganglion cell dysfunction (1), caused by mutations in mitochondrial DNA (mtDNA), which affect complex I (NADH-ubiquinone oxidoreductase) of the mitochondrial respiratory chain (2,3). Although rare (estimated prevalence of 1 in 27,000-45,000), it affects all ages and gender, causing rapid and severe, bilateral (usually sequential), painless loss of central vision (4-7). Spon-558
Teaching NeuroImages: Mind the gap! Postfixational blindness due to traumatic rupture of the opti... more Teaching NeuroImages: Mind the gap! Postfixational blindness due to traumatic rupture of the optic chiasm A 59-year-old woman visited the ophthalmologist for a routine examination. Ever since a severe head injury with frontal lobe damage at age 16 years, she had experienced intermittent diplopia and difficul-ties finding misplaced objects, but worked as a clerk throughout her life. Ocular motility was full with only slight exotropia, but perimetry revealed com-plete bitemporal hemianopia (figure 1, A and C). Bitemporal hemianopia is caused by disruption of crossing nerve fibers in the optic chiasm (figure 2), usually due to suprasellar masses, or rarely, follow-ing head trauma.1 Without corresponding retinal Figure 1 Postfixational blindness due to traumatic rupture of the optic chiasm (A, C) Standard perimetry shows complete bitemporal hemianopia. The monocular visual fields of the right eye (blue) and the left eye (red) are superimposed. (B, D) Perimetry during convergence on a ne...
We report on a series of patients with acute strabismus related to heroin and methadone intake or... more We report on a series of patients with acute strabismus related to heroin and methadone intake or withdrawal, discuss possible mechanisms involved in this clinical picture and make recommendations for work-up and referral. Retrospective study. Five patients presented with acute esotropia within days of heroin withdrawal, and two patients developed exotropia related to heroin or methadone intake. Neurological work-up and neuroimaging was non-contributory in all four patients who were examined. Acute esotropia with double vision is a disturbing side effect of heroin withdrawal, and, similarly, acute exotropia may be related to heroin intake. In the absence of focal neurological signs, further work-up is not mandatory. Referral to a specialised orthoptic service is beneficial in offering the patient symptomatic treatment and reassurance, thus supporting successful withdrawal therapy.
BACKGROUND Brown syndrome is characterized by a restrictive elevation deficit of the affected eye... more BACKGROUND Brown syndrome is characterized by a restrictive elevation deficit of the affected eye in adduction. Besides the well-known congenital form, different acquired etiologies including inflammation, trauma, and surgery may prevent the superior oblique (SO) tendon from gliding freely through the trochlea on attempted upgaze. We present MRI findings in pediatric and adult patients with inflammatory acquired Brown syndrome. METHODS Retrospective review of clinical and MRI findings of 6 patients (4 children: median age 8.4 years [range 6.1-8.7]; 2 adults: age 46.4 and 51.1 years). Median follow-up was 23 months (range 1-52). RESULTS In all 6 patients, orbital MRI demonstrated inflammatory changes of the SO tendon-trochlea complex. A striking feature was circumferential contrast enhancement of the trochlea with central sparing where the tendon passes, reminiscent of an eyelet. In all cases, the motility restriction improved either spontaneously or with systemic anti-inflammatory treatment. Although both adult patients had a history of known seronegative spondyloarthritis, there was no associated systemic condition in the children in our series. CONCLUSIONS Both in children and in adults, MRI can provide evidence of inflammatory changes located at the trochlea-tendon complex in acquired Brown syndrome here referred to as the "eyelet sign," which may be helpful in confirming the clinical diagnosis and guide appropriate treatment.
Purpose The characteristic findings in accidental head injury consist of linear skull fracture, e... more Purpose The characteristic findings in accidental head injury consist of linear skull fracture, epidural haematoma, localized subdural haematoma, or cortical contusion because of a linear or translational impact force. Retinal haemorrhages have been found, although uncommon, in accidental head trauma. Methods We performed a retrospective study of 24 consecutive cases of children with severe head injuries caused by falls. Inclusion criteria were skull fractures and/or intracranial haemorrhages documented by computerized tomography. All patients underwent a careful ophthalmic examination including dilated indirect fundoscopy within the first 48 h following admission. Results No retinal haemorrhages could be found in patients whose accidents were plausible and physical and imaging findings were compatible with reported histories. Excessive bilateral retinal haemorrhages were found in only three children with the typical signs of shaken baby syndrome. In eight children, trauma had led to orbital roof fractures. Conclusions Retinal haemorrhages were not found in any of the patients with accidental trauma despite the severity of their head injuries. Hence, we add more evidence that there are strong differences between the ocular involvement in accidental translational trauma and those in victims of non-accidental trauma. Fall-related injuries carry a very low risk of retinal haemorrhages.
We report the longterm follow-up of children with optic nerve avulsion (ONA) caused by traumatic ... more We report the longterm follow-up of children with optic nerve avulsion (ONA) caused by traumatic events. The remarkable differences in courses and outcomes may elucidate the spectrum of ONA-associated symptoms and injuries. During the last 15 years, three children with ONA were referred to our department. These cases are presented with special attention to their longterm follow-up. Two patients suffered from complete ONA after head injury. The third patient presented with partial ONA caused by a bicycle accident. Longterm follow-up varied between 7 and 15 years. In the first patient, a pale swollen retina without any visible retinal vasculature was observed early in the course of follow-up. The retina later completely detached. In the second patient, extended fibroglial scarring occurred and an extremely large epiretinal membrane formed and was finally released spontaneously into the vitreous. The third patient developed only mild fibroglial scarring and retinal pigment epithelium hyperplasia. The optic nerve head in this patient came to resemble a morning glory disc. Optic nerve avulsion can adopt different courses and outcomes in different patients. Final visual outcome seems to depend on the degree of visual acuity immediately after injury. Substantial intraocular architecture changes can occur as a result of ONA.
Retinal hemorrhages have been described as a component of high altitude retinopathy (HAR) in asso... more Retinal hemorrhages have been described as a component of high altitude retinopathy (HAR) in association with altitude illness. In this prospective high altitude study, we aimed to gain new insights into the pathophysiology of HAR and explored whether HAR could be a valid early indicator of altitude illness.
Little is known about the ocular and cerebral blood flow during exposure to increasingly hypoxic ... more Little is known about the ocular and cerebral blood flow during exposure to increasingly hypoxic conditions at high altitudes. There is evidence that an increase in cerebral blood flow resulting from altered autoregulation constitutes a risk factor for acute mountain sickness (AMS) and high-altitude cerebral edema (HACE) by leading to capillary overperfusion and vasogenic cerebral edema. The retina represents the only part of the central nervous system where capillary blood flow is visible and can be measured by noninvasive means. In this study we aimed to gain insights into retinal and choroidal autoregulatory properties during hypoxia and to correlate circulatory changes to symptoms of AMS and clinical signs of HACE. This observational study was performed within the scope of a high-altitude medical research expedition to Mount Muztagh Ata (7,546 m). Twenty seven participants underwent general and ophthalmic examinations up to a maximal height of 6,800 m. Examinations included fund...
Oculomotor palsy with cyclic spasms is an extremely rare condition whose exact pathophysiology re... more Oculomotor palsy with cyclic spasms is an extremely rare condition whose exact pathophysiology remains a mystery. We followed a boy from the onset of symptoms at the age of ten months until 15 years and documented the case with video oculography. In addition, he was diagnosed with hereditary motor and sensory neuropathy (Charcot-Marie-Tooth disease type 1). Although a pure coincidence cannot be ruled out, it is conceivable that the underlying demyelinating neuropathy of this patient rendered the oculomotor nerve more susceptible to damage.
L eber hereditary optic neuropathy (LHON) is a form of blindness due to retinal ganglion cell dys... more L eber hereditary optic neuropathy (LHON) is a form of blindness due to retinal ganglion cell dysfunction (1), caused by mutations in mitochondrial DNA (mtDNA), which affect complex I (NADH-ubiquinone oxidoreductase) of the mitochondrial respiratory chain (2,3). Although rare (estimated prevalence of 1 in 27,000-45,000), it affects all ages and gender, causing rapid and severe, bilateral (usually sequential), painless loss of central vision (4-7). Spon-558
Teaching NeuroImages: Mind the gap! Postfixational blindness due to traumatic rupture of the opti... more Teaching NeuroImages: Mind the gap! Postfixational blindness due to traumatic rupture of the optic chiasm A 59-year-old woman visited the ophthalmologist for a routine examination. Ever since a severe head injury with frontal lobe damage at age 16 years, she had experienced intermittent diplopia and difficul-ties finding misplaced objects, but worked as a clerk throughout her life. Ocular motility was full with only slight exotropia, but perimetry revealed com-plete bitemporal hemianopia (figure 1, A and C). Bitemporal hemianopia is caused by disruption of crossing nerve fibers in the optic chiasm (figure 2), usually due to suprasellar masses, or rarely, follow-ing head trauma.1 Without corresponding retinal Figure 1 Postfixational blindness due to traumatic rupture of the optic chiasm (A, C) Standard perimetry shows complete bitemporal hemianopia. The monocular visual fields of the right eye (blue) and the left eye (red) are superimposed. (B, D) Perimetry during convergence on a ne...
We report on a series of patients with acute strabismus related to heroin and methadone intake or... more We report on a series of patients with acute strabismus related to heroin and methadone intake or withdrawal, discuss possible mechanisms involved in this clinical picture and make recommendations for work-up and referral. Retrospective study. Five patients presented with acute esotropia within days of heroin withdrawal, and two patients developed exotropia related to heroin or methadone intake. Neurological work-up and neuroimaging was non-contributory in all four patients who were examined. Acute esotropia with double vision is a disturbing side effect of heroin withdrawal, and, similarly, acute exotropia may be related to heroin intake. In the absence of focal neurological signs, further work-up is not mandatory. Referral to a specialised orthoptic service is beneficial in offering the patient symptomatic treatment and reassurance, thus supporting successful withdrawal therapy.
BACKGROUND Brown syndrome is characterized by a restrictive elevation deficit of the affected eye... more BACKGROUND Brown syndrome is characterized by a restrictive elevation deficit of the affected eye in adduction. Besides the well-known congenital form, different acquired etiologies including inflammation, trauma, and surgery may prevent the superior oblique (SO) tendon from gliding freely through the trochlea on attempted upgaze. We present MRI findings in pediatric and adult patients with inflammatory acquired Brown syndrome. METHODS Retrospective review of clinical and MRI findings of 6 patients (4 children: median age 8.4 years [range 6.1-8.7]; 2 adults: age 46.4 and 51.1 years). Median follow-up was 23 months (range 1-52). RESULTS In all 6 patients, orbital MRI demonstrated inflammatory changes of the SO tendon-trochlea complex. A striking feature was circumferential contrast enhancement of the trochlea with central sparing where the tendon passes, reminiscent of an eyelet. In all cases, the motility restriction improved either spontaneously or with systemic anti-inflammatory treatment. Although both adult patients had a history of known seronegative spondyloarthritis, there was no associated systemic condition in the children in our series. CONCLUSIONS Both in children and in adults, MRI can provide evidence of inflammatory changes located at the trochlea-tendon complex in acquired Brown syndrome here referred to as the "eyelet sign," which may be helpful in confirming the clinical diagnosis and guide appropriate treatment.
Purpose The characteristic findings in accidental head injury consist of linear skull fracture, e... more Purpose The characteristic findings in accidental head injury consist of linear skull fracture, epidural haematoma, localized subdural haematoma, or cortical contusion because of a linear or translational impact force. Retinal haemorrhages have been found, although uncommon, in accidental head trauma. Methods We performed a retrospective study of 24 consecutive cases of children with severe head injuries caused by falls. Inclusion criteria were skull fractures and/or intracranial haemorrhages documented by computerized tomography. All patients underwent a careful ophthalmic examination including dilated indirect fundoscopy within the first 48 h following admission. Results No retinal haemorrhages could be found in patients whose accidents were plausible and physical and imaging findings were compatible with reported histories. Excessive bilateral retinal haemorrhages were found in only three children with the typical signs of shaken baby syndrome. In eight children, trauma had led to orbital roof fractures. Conclusions Retinal haemorrhages were not found in any of the patients with accidental trauma despite the severity of their head injuries. Hence, we add more evidence that there are strong differences between the ocular involvement in accidental translational trauma and those in victims of non-accidental trauma. Fall-related injuries carry a very low risk of retinal haemorrhages.
We report the longterm follow-up of children with optic nerve avulsion (ONA) caused by traumatic ... more We report the longterm follow-up of children with optic nerve avulsion (ONA) caused by traumatic events. The remarkable differences in courses and outcomes may elucidate the spectrum of ONA-associated symptoms and injuries. During the last 15 years, three children with ONA were referred to our department. These cases are presented with special attention to their longterm follow-up. Two patients suffered from complete ONA after head injury. The third patient presented with partial ONA caused by a bicycle accident. Longterm follow-up varied between 7 and 15 years. In the first patient, a pale swollen retina without any visible retinal vasculature was observed early in the course of follow-up. The retina later completely detached. In the second patient, extended fibroglial scarring occurred and an extremely large epiretinal membrane formed and was finally released spontaneously into the vitreous. The third patient developed only mild fibroglial scarring and retinal pigment epithelium hyperplasia. The optic nerve head in this patient came to resemble a morning glory disc. Optic nerve avulsion can adopt different courses and outcomes in different patients. Final visual outcome seems to depend on the degree of visual acuity immediately after injury. Substantial intraocular architecture changes can occur as a result of ONA.
Retinal hemorrhages have been described as a component of high altitude retinopathy (HAR) in asso... more Retinal hemorrhages have been described as a component of high altitude retinopathy (HAR) in association with altitude illness. In this prospective high altitude study, we aimed to gain new insights into the pathophysiology of HAR and explored whether HAR could be a valid early indicator of altitude illness.
Little is known about the ocular and cerebral blood flow during exposure to increasingly hypoxic ... more Little is known about the ocular and cerebral blood flow during exposure to increasingly hypoxic conditions at high altitudes. There is evidence that an increase in cerebral blood flow resulting from altered autoregulation constitutes a risk factor for acute mountain sickness (AMS) and high-altitude cerebral edema (HACE) by leading to capillary overperfusion and vasogenic cerebral edema. The retina represents the only part of the central nervous system where capillary blood flow is visible and can be measured by noninvasive means. In this study we aimed to gain insights into retinal and choroidal autoregulatory properties during hypoxia and to correlate circulatory changes to symptoms of AMS and clinical signs of HACE. This observational study was performed within the scope of a high-altitude medical research expedition to Mount Muztagh Ata (7,546 m). Twenty seven participants underwent general and ophthalmic examinations up to a maximal height of 6,800 m. Examinations included fund...
Oculomotor palsy with cyclic spasms is an extremely rare condition whose exact pathophysiology re... more Oculomotor palsy with cyclic spasms is an extremely rare condition whose exact pathophysiology remains a mystery. We followed a boy from the onset of symptoms at the age of ten months until 15 years and documented the case with video oculography. In addition, he was diagnosed with hereditary motor and sensory neuropathy (Charcot-Marie-Tooth disease type 1). Although a pure coincidence cannot be ruled out, it is conceivable that the underlying demyelinating neuropathy of this patient rendered the oculomotor nerve more susceptible to damage.
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