Isolated Internal Ophthalmoplegia from Posterior Cerebral Artery Neurovascular Conflict.

We report a rare case of recurrent isolated internal ophthalmoplegia attributed to oculomotor nerve (CN III) compression by the posterior cerebral artery (PCA). A 30-year-old female patient presented with recurrent right-sided headaches, right periorbital pain, and slight anisocoria. Slit-lamp examination revealed normal anterior and posterior segments except for vermiform movements of the right pupil with a temporal hyporeactive flat area. Tonic pupils were ruled out with pilocarpine 0.1% testing. Suspecting an internal ophthalmoplegia, magnetic resonance imaging was ordered which demonstrated the right CN III indented by the PCA, fulfilling the criteria of a neurovascular conflict. The evaluation of unilateral mydriasis from internal ophthalmoplegia should prompt neuroimaging with exclusion of aneurysmal or compressive lesions. CN III palsy can rarely be caused by vascular anatomical variants because of the proximity of the posterior intracranial circulation and CN III. Newer, more precise imaging techniques will better help characterize neurovascular conflicts presenting as cranial nerve palsies.

Frosted branch angiitis as an immune recovery response in newly diagnosed acquired immunodeficiency syndrome and systemic cytomegalovirus infection.

Frosted branch angiitis (FBA) is an uncommon form of severe retinal perivasculitis associated with systemic inflammatory/infectious diseases. In this report, we describe a case of FBA and macular edema as a result of immune recovery response in a patient newly diagnosed with HIV infection and cytomegalovirus viremia.

Spiroplasma species as a rare cause of congenital cataract and uveitis: a case series.

BACKGROUND: To date, only four cases of ocular spiroplasma infection have been reported in the entire ophthalmic literature. We add two more cases to raise awareness of this sight-threatening congenital disease that manifests as cataract with ocular inflammation. CASE PRESENTATION: Both infants were referred for cataracts associated with ocular inflammation. Case 1, a 3-week-old neonate presented with unilateral cataract, ocular inflammation and elevated intraocular pressure. Case 2 was a 3-month-old infant with bilateral cataract and panuveitis. Lensectomies with or without vitrectomy and subsequent analyses of the specimens were performed. Transmission electron microscopy and multiplex polymerase chain reaction or 16 s rRNA gene polymerase chain reaction revealed spiroplasma species. CONCLUSIONS: Spiroplasma as a very rare cause for congenital cataract might be underdiagnosed. We recommend performing polymerase chain reaction to probe for spiroplasma species in congenital cataracts with an inflammatory component.

Comparison of VEP with contrast sensitivity and other measurements of central visual function.

PURPOSE: In order to evaluate alternative visual acuity testing techniques, especially to discriminate between small changes and for high visual acuity, we conducted a study covering several state-of-the-art techniques. METHODS: In this cross-sectional study, a homogeneous cohort of healthy and young patients (n = 33; 66 eyes) underwent ETDRS vision acuity (VA) testing, testing for contrast sensitivity (CS), VA determination with spatial frequency sweep visual evoked potentials (VEP) and a series of examinations of perifoveal retinal nerve fibre layer thickness (RNFLT) using Spectralis SD-OCT. To simulate the effect of artificial media opacity, CS, and VEP were repeated with Bangerter foils. RESULTS: We found that Bangerter foils can be used to reduce VA effectively measured by VA testing and VEP VA. CS correlated significantly with VA (correlation coefficients ranging from 0.54 to 0.77). VEP may be used to estimate VA; nevertheless, we found no significant correlation. RNFLT did not correlate significantly with VA. CONCLUSION: CS seems to correlate well with VA when used for high VA. All other used examinations seem to have difficulties distinguishing between small differences in VA or when the VA is high.

Visual functions in phenylketonuria-evaluating the dopamine and long-chain polyunsaturated fatty acids depletion hypotheses.

BACKGROUND: In phenylketonuria presymptomatic treatment following newborn screening prevents severe mental and physical impairment. The reasons for subtle impairments of cerebral functions despite early treatment remain unclear. We assessed a broad spectrum of visual functions in early-treated patients with phenylketonuria and evaluated two hypotheses-the dopamine and the long-chain polyunsaturated fatty acids (LCPUFAs) depletion hypotheses. METHODS: Contrast sensitivity, colour vision, electroretinography, frequency doubling technology campimetry (FDT), and their relation with blood phenylalanine and docosahexaenoic acid levels were assessed in 36 patients with phenylketonuria and 18 age-matched healthy controls. RESULTS: Contrast sensitivity was significantly lower and total error scores in colour vision significantly higher in patients than controls. Electroretinography results differed significantly between patients and controls. We found a trend for the effect of phenylalanine-levels on contrast sensitivity and a significant effect on colour vision/FDT results. Docosahexaenoic acid levels in erythrocytes were not associated with visual functions. CONCLUSION: This is the first evaluation of visual functions in phenylketonuria using a comprehensive ophthalmological test battery. We found no evidence supporting the long-chain polyunsaturated fatty acids depletion hypothesis. However, the effect of phenylalanine-levels on visual functions suggests that imbalance between phenylalanine and tyrosine may affect retinal dopamine levels in phenylketonuria. This is supported by the similar patterns of visual functions in patients with phenylketonuria observed in our study and patients with Parkinson's disease.

Retinal blood flow velocity measured by retinal function imaging in retinitis pigmentosa.

BACKGROUND: To measure the retinal blood flow velocity in patients with retinitis pigmentosa using the retinal function imaging technique. METHODS: The clinical observational investigation included a study group of five eyes of five patients (age: 55.7 ± 8.6 years) with retinitis pigmentosa (RP) and a control group of five eyes of five healthy subjects. We used a randomly chosen eye of the RP patients, and compared its results to the normal subjects using a mixed linear model, correcting for heart rate, age, and gender. RESULTS: The mean blood velocity in the narrow retinal veins (1.7 ± 0.35 cm/s versus 3.0 ± 0.35 cm/s; P < 0.001) and wide retinal veins (1.5 ± 0.35 cm/s versus 3.1 ± 0.30 cm/s; P < 0.001) was significantly lower in the study group than in the control group not correcting for heart rate, age or gender. Correspondingly, the arterial blood flow velocity was significantly lower in the study group than in the control group for the narrow arterial vessels (2.3 ± 0.55 versus 4.2 ± 0.5; P = 0.006) and for the wide retinal arteries (2.5 ± 1.05 cm/s versus 4.8 ± 1.0 cm/s; P < 0.001). CONCLUSIONS: Using the retinal function imaging technology revealed significantly lower retinal blood flow velocities in the small and large retinal vessels in patients with retinitis pigmentosa than in healthy subjects. This corresponds with the known decrease in the retinal vessel diameters as observed upon ophthalmoscopy in patients with retinitis pigmentosa. Retinal function imaging technology may hold promise for measurements of retinal blood flow parameters.

Ophthalmological aspects of Pierson syndrome.

PURPOSE: To study the ocular phenotype of Pierson syndrome and to increase awareness among ophthalmologists of the diagnostic features of this condition. DESIGN: Retrospective, observational case series. METHODS: A multicenter study of 17 patients with molecularly confirmed Pierson syndrome. The eye findings were reviewed and compared to pertinent findings from the literature. RESULTS: The most characteristic ocular anomaly was microcoria. A wide range of additional abnormalities were found, including posterior embryotoxon, megalocornea, iris hypoplasia, cataract, abnormal lens shape, posterior lenticonus, persistent fetal vasculature, retinal detachment, variable axial lengths, and glaucoma. There was high interocular and intrafamilial variability. CONCLUSIONS: Loss-of-function mutations in laminin beta2 (LAMB2) cause a broad range of ocular pathology, emphasizing the importance of laminin beta2 in eye development. Patients with Pierson syndrome can initially present with ocular signs alone. In newborns with marked bilateral microcoria, Pierson syndrome should be considered and renal function investigated.

Mevalonate kinase deficiency: enlarging the clinical and biochemical spectrum.

OBJECTIVE: Mevalonic aciduria as a result of mevalonate kinase deficiency is an inborn error of cholesterol biosynthesis characterized by dysmorphology, psychomotor retardation, progressive cerebellar ataxia, and recurrent febrile crises, usually manifesting in early infancy, accompanied by hepatosplenomegaly, lymphadenopathy, arthralgia, and skin rash. The febrile crises are similar to those observed in hyperimmunoglobulinemia D and periodic fever syndrome (HIDS). Pathogenic mutations in the mevalonate kinase gene in both disorders have demonstrated a common genetic basis. Our aim was to describe the clinical picture of adolescent patients with mevalonate kinase deficiency and to expand the clinical and biochemical spectrum of mevalonate kinase deficiency, particularly with regard to HIDS. METHODS: We report the clinical history and biochemical findings of 3 patients with mevalonic aciduria. RESULTS: In 2 siblings with mevalonic aciduria, a 15-year-old girl and a 14-year-old boy, the phenotype shifted with age. Ataxia has become the predominant clinical manifestation, whereas the febrile attacks occur less frequently but as yet have not disappeared. Both of them show marked elevations of immunoglobulin D (IgD). Psychomotor development is retarded but not regressive. Short stature developed in both patients. Additional findings include the development of retinal dystrophy and cataracts in both of them. The third patient is a 6-year-old boy who presented at the age of 5 years with cerebellar ataxia and retinal dystrophy. He is different from all known patients with mevalonic aciduria because of the mild neurologic involvement and because he has never developed febrile crises. In addition, levels of IgD were repeatedly normal. CONCLUSION: The clinical and biochemical spectrum of patients with mevalonic aciduria is heterogeneous. Manifestations of the disease seem to be age dependent, as evident from this first report of adolescent patients. In patients who survive infancy, short stature, ataxia caused by cerebellar atrophy, and ocular involvement with retinal dystrophy become predominant findings. Recurrent febrile crises seem to diminish with increasing age and may not even be an obligatory finding. Elevation of IgD is most likely a secondary phenomenon that seems to be linked to recurrent febrile crises.