Axial length, refractive error, and keratometry in patients with branch retinal vein occlusion

PURPOSE: To evaluate ocular parameters that may predispose to the development of branch retinal vein occlusion (BRVO). METHODS: This prospective study included patients with unilateral BRVO evaluated in the authors' clinic. The mean period from the acute phase was 2.29 +/- 1.57 years (range 1-6 years). All patients underwent a complete ophthalmologic examination including subjective refraction, axial length measurements, and keratometry readings. The fellow eye served as a control in each patient. The variables of interest were compared between the affected eye and the fellow eye using the parametric t-test and the nonparametric Wilcoxon test. RESULTS: Twenty-four consecutive patients (14 women, 10 men, mean age 62.4 years) were included in the study. The mean axial length in the affected eye was significantly shorter compared to the mean fellow eye length. No difference was found between the two eyes in mean subjective refraction or mean keratometry readings. CONCLUSIONS: The authors found that eyes with BRVO have a shorter axial length compared to the fellow eye in the same patient.     

A reliable MR measurement of medial temporal lobe width from the Sunnybrook Dementia Study

We studied the hippocampal angle and spatial relationships of medial temporal lobe (MTL) structures, using midbrain colliculi and inter-collicular sulcus (ICS) as landmarks, and measured MTL width on axial 3D-T1-weighted MRI at ICS level in 41 normal, aged participants. Mean hippocampal angle was 29 degrees (range 17-42 degrees ) caudal to the anterior-posterior commissure (AC-PC) line. The slice at the ICS, parallel to the long axis of the hippocampus, best revealed a longitudinal view of hippocampus and parahippocampal gyrus in 76% of participants, compared to only 7% when slices were 20 degrees caudal to orbitomeatal line (OML), an accepted technique used to examine MTL width in previous CT studies. The MTL width measured midway and at its thinnest between the anterior-posterior borders of the midbrain was highly reproducible (intraclass correlation coefficients >0.98) using these new methods. These simple decision rules, individualized orientation along the hippocampus and using a standardized landmark like the ICS, make these measures more comparable across subjects, and hence more useful in detecting and monitoring MTL atrophy in dementia.     

Congenital ptosis and amblyopia: a retrospective study of 130 cases

PURPOSE: To provide supplementary data on the association between congenital ptosis and amblyopia. METHODS: In a retrospective chart study of 130 patients whose congenital ptosis was surgically corrected between 1987 and 1999, 27 (20.8%) had strabismus and 30 (23%) had amblyopia. In 9 patients (6.3%), it was not attributable to any cause except ptosis. RESULTS: There was a high incidence (6.9%) of amblyopia in patients with congenital ptosis. CONCLUSION: We recommend early examination and follow-up of patients with congenital ptosis to diagnose and treat any subsequent amblyopia. Surgery may be indicated should stimulus deprivation amblyopia develop.     

Replacing the Amsler grid: a new method for monitoring patients with age-related macular degeneration

PURPOSE: To investigate a method that uses hyperacuity, the Macular Computerized Psychophysical Test (MCPT), to evaluate the central macular visual field in patients with age-related macular degeneration (AMD). DESIGN: Prospective case-control study of a diagnostic test. PARTICIPANTS AND CONTROLS: One hundred eight eyes of 108 Patients with AMD and 51 eyes of 51 age-matched patients with no retinal disease. Patients with AMD included 32 (30%) patients with choroidal neovascularization (CNV), 23 (21%) with geographic atrophy (GA), 35 (32%) with AMD with high-risk characteristics (HRC), and 18 (17%) with early AMD with non-HRC. TESTING: Each subject underwent the MCPT, in which a virtual line composed of dots (white dots on a black background, maximal contrast) is flashed across different macular loci to a perifoveal radius of 7 degrees. Patients' responses were recorded and automatically analyzed using a specific algorithm developed before the onset of the study. All patients also underwent a supervised Amsler grid examination on the encounter before or after the MCPT in random order. MAIN OUTCOME MEASURES: Distortion, scotoma, or blurring perceived by the patient after a swift change of fixation was considered positive on the MCPT. Any perception of distortion, scotoma, or blurring was considered positive on the Amsler grid. RESULTS: Of the 32 patients with CNV, 30 (94%) were found positive on the MCPT and 11 (34%) were found positive on the Amsler grid. Of the 23 GA patients, 21 (91%) were found positive on the MCPT and 7 (30%) were found positive on the Amsler grid. Of the 35 HRC patients, 28 (80%) were found positive on the MCPT and 3 (9%) were found positive on the Amsler grid, and of the 18 early AMD with non-HRC patients, 8 (44%) were found positive on the MCPT and 3 (17%) were found positive on the Amsler grid. Of the 51 controls, 3 (6%) were positive on the MCPT and 1 (2%) was positive on the Amsler grid. CONCLUSIONS: The MCPT was superior to the Amsler grid in detecting AMD-related lesions in this cohort. Studies are underway to determine whether the MCPT is feasible for home monitoring to provide early detection of progression to CNV.     

Three brain SPECT region-of-interest templates in elderly people: normative values, hemispheric asymmetries, and a comparison of single- and multihead cameras.

The purpose of this study was to generate anatomically guided region-of-interest (ROI) brain SPECT templates based on scans of elderly healthy volunteers. We describe normal tracer uptake and hemispheric asymmetries for each of 3 camera systems and compare these characteristics among systems. METHODS: 99mTc-hexamethyl propyleneamine oxime SPECT scans were acquired from 28 elderly healthy volunteers (mean age [+/-SD], 70.3 +/- 6.5 y) on a single-head rotating gamma camera (n = 15) or on dual- (n = 18) or triple-head (n = 13) cameras. The average number of counts in each ROI was calculated and referenced to counts in a cerebellar ROI, providing semiquantitative regional cerebral blood flow (rCBF) ratios. For the templates and ROI map, base images of a healthy volunteer were obtained with each camera. Data from individuals scanned with 2 cameras on the same day (n = 15) were used to evaluate rCBF differences across cameras. For each camera, averaged SPECT templates were made using automated image registration. The base volunteer's T1-weighted MR image was converted to stereotactic space with dimensions similar to those of the SPECT templates, and 79 bilateral ROIs were defined. To obtain ROI rCBF ratios, we aligned individual images to their appropriate template and then to this modified MR image. RESULTS: The ROI coefficients of variation indicated that the fit of the ROIs was acceptable (0.07-0.35). Mean rCBF ratios ranged from 0.57 to 1.0, 0.67 to 1.01, and 0.63 to 1.00 for single-, dual-, and triple-head cameras, respectively. The cuneus, occipital cortex, occipital pole, middle temporal gyrus, and posterior middle frontal gyrus showed consistent hemispheric asymmetry (right side greater than left side in 83%-100% of individuals). Mean rCBF ratios did not differ between dual- and triple-head cameras, whereas the ratios for single- and dual-head cameras differed significantly (39 ROIs differed), even after smoothing and filtering the dual-head images to the level of the single-head images. CONCLUSION: The use of SPECT templates based on elderly healthy volunteers is an important feature of this technique because most available templates have used young individuals. Another important feature is the use of MR image-based ROIs. These procedures are versatile because they use more than 1 camera. They can easily be implemented in clinical and research settings to detect camera-specific, abnormal deviations in rCBF ROI ratios and asymmetry magnitudes in diseases associated with aging, such as stroke and dementia.     

Persistent 7-tesla phase rim predicts poor outcome in new multiple sclerosis patient lesions

BACKGROUND. In some active multiple sclerosis (MS) lesions, a strong immune reaction at the lesion edge may contain growth and thereby isolate the lesion from the surrounding parenchyma. Our previous studies suggest that this process involves opening of the blood-brain barrier in capillaries at the lesion edge, seen on MRI as centripetal contrast enhancement and a colocalized phase rim. We hypothesized that using these features to characterize early lesion evolution will allow in vivo tracking of tissue degeneration and/or repair, thus improving the evaluation of potential therapies for chronic active lesions.METHODS. Centripetally and centrifugally enhancing lesions were studied in 17 patients with MS using 7-tesla MRI. High-resolution, susceptibility-weighted, T1-weighted (before/after gadolinium), and dynamic contrast–enhanced scans were acquired at baseline and months 1, 3, 6, and 12. For each lesion, time evolution of the phase rim, lesion volume, and T1 hypointensity were assessed. In autopsies of 3 progressive MS cases, the histopathology of the phase rim was determined.RESULTS. In centripetal lesions, a phase rim colocalized with initial contrast enhancement. In 12 of 22, this phase rim persisted after enhancement resolved. Compared with centripetal lesions with transient rim, those with persistent rim had less volume shrinkage and became more T1 hypointense between months 3 and 12. No centrifugal lesions developed phase rims at any time point. Pathologically, persistent rims corresponded to an iron-laden inflammatory myeloid cell population at the edge of chronic demyelinated lesions.CONCLUSION. In early lesion evolution, a persistent phase rim in lesions that shrink least and become more T1 hypointense over time suggests that the rim might mark failure of early lesion repair and/or irreversible tissue damage. In later stages of MS, phase rim lesions continue to smolder, exerting detrimental effects on affected brain tissue.TRIAL REGISTRATION. {"type":"clinical-trial","attrs":{"text":"NCT00001248","term_id":"NCT00001248"}}NCT00001248.FUNDING. The Intramural Research Program of NINDS supported this study.     

Anatomy of Tenons capsule

Background: The microscopic and macroscopic anatomy of the anterior and posterior Tenons capsule is described. Methods: An observational anatomic study of twelve orbits of 6 cadavers (mean age 79.5 years) were examined microscopically and 8 orbits of 4 cadavers (mean age 76.8 years) were examined macroscopically. After orbital exenteration, an X‐shaped incision was made in the specimens to include the posterior part of the globe. The sections were divided into four parts: superomedial; inferomedial; superolateral; and inferolateral. In the macroscopically examined specimens, the eyelids and globes were removed from the exenterated tissues and the appearance of Tenons capsule was studied. Results: In the microscopic study, Tenons capsule covered the sclera beneath the conjunctiva and contained smooth muscle fibres in the anterior area. This anterior fascia, which had a thick appearance, reached the globe equator. From there, the capsule of the orbital fat, which contained no smooth muscle fibres, enveloped the sclera and reached the optic nerve. This was defined as the posterior capsule. In the macroscopic specimens, Tenons capsule had a thick and fibrous white appearance in the anterior area. More posteriorly, the capsule was thinner and more translucent. This thin capsular part was generally larger in the lateral area than in the medial area. Conclusions: Tenons capsule is composed of an anterior thick fibrous tissue comprising the orbital smooth muscle network and the posterior thin fibrous capsule of the orbital fat.     

Colour Doppler ultrasound imaging findings in paediatric periocular and orbital haemangiomas

Purpose: To evaluate the combined grey‐scale ultrasonography (US) and colour Doppler imaging (CDI) as the first and primary imaging modalities in diagnosing paediatric orbital haemangiomas. Methods: The charts of 20 consecutive children with a periorbital mass echographically diagnosed as a haemangioma between January 2004 and June 2009 in the Tel‐Aviv Sourasky Medical Center were reviewed. Data on demographic details, clinical findings, US and CDI characteristics, treatment and outcome were retrieved. Results: Twelve (60%) haemangiomas were located on the upper eyelid, five in the lower eyelid (25%) and three in the medial cantus (15%). The tumour resolved completely in 10 children (50%) and in 10 children (50%) partial resolution was documented. Seven (35%) patients underwent treatment (intralesional or oral steroids or propranolol). Grey‐scale US depicted a solid‐tissue mass with low internal echogenicity. Mean haemangioma volume was 1.33 cm³. Colour Doppler imaging demonstrated intralesional flow with a mean peak systolic velocity of 15.2 cm per second and a mean resistance index of 0.51. All US and CDI examinations were carried out on alert children and no sedation or general anaesthesia was needed. During mean follow‐up time of 23 months, no child required any additional imaging or diagnostic procedures to confirm the diagnosis. Conclusion: Combined US and CDI are suggested as the first imaging modalities in cases with a suspected diagnosis of periocular and orbital capillary haemangioma.     

Isotretinoin-induced adult onset Still's disease

We describe a 21-year old man who was diagnosed as having adult onset Still's disease (AOSD) in association with isotretinoin treatment for acne conglobata. The patient was febrile, with a macular salmon pink rash, arthritis, hepatosplenomegaly, and axial lymphadenopathy. Laboratory results showed leukocytosis, mild liver dysfunction and negative rheumatoid factor and antinuclear antibodies. Isotretinoin, an orally active derivative of vitamin A, has been associated with various rheumatologic conditions such as arthralgia, myalgia, vasculitis and arthritis. The etiology of rheumatic disorders associated with retinoids is still obscure; however, it is presumed that immunomodulation by several mechanisms (such as an alteration of the cytokine balance) is probably ascribable to this interesting association.