The nasal circling phenomenon pattern of visual field loss on automated static perimetry Implications on the neuroanatomy of the optic chiasm

1999 ◽  
Vol 21 (1) ◽  
pp. 1-11
Author(s):  
Lenworth N. Johnson ◽  
Wendy Yee ◽  
Edward V. Colapinto
2021 ◽  
Vol 3 (4) ◽  
pp. 244-249
Author(s):  
Norazlida Ibrahim ◽  
Raja Norliza Binti Raja Omar ◽  
Mae-Lynn Catherine Bastion

Pituitary apoplexy in pregnancy is a potentially fatal condition caused by acute ischaemic infarction or haemorrhage of pre-existing pituitary adenoma or within a physiologically enlarged pituitary gland. It has a wide spectrum of clinical presentations ranging from a mild headache to sudden collapsed. Here, we report a life-threatening case of pituitary apoplexy in a non-functioning pituitary macroadenoma occurring during pregnancy that presented with bilateral blurring of vision. Visual field showed bitemporal superior quadrantanopia. Urgent non-contrast brain MRI revealed an acute expansion of a hemorrhagic pituitary lesion complicated with local compression to the optic chiasm. The patient underwent an uneventful right supraorbital craniotomy and excision of the tumour under general anaesthesia with no foetal loss. The repeated visual field at 2 weeks after surgery showed recovering visual field defect. Hence, early neurosurgical intervention is advisable to prevent mortality and morbidity due to permanent visual field loss.


Author(s):  
P. N. Skonnikov ◽  
D. V. Trofimov

Abstract. Some diseases, for instance, a glaucoma, cause visual field defects. For the timely diagnostics of such defects, various methods are used. One of the state-of-the-art diagnostic methods is automated static perimetry. The method of static perimetry consists in the light sensitivity determination in different parts of the visual field using stationary objects of variable luminosity. When scanning the visual field in this way, an important factor is the control of gaze fixation at the fixation point. The greatest accuracy in determining the gaze fixation position is achieved by the method of the pupil visual tracking using a video camera.In this paper, four groups of visual tracking algorithms are considered: segmentation-based methods, correlation methods, methods based on optical flow and on weighted average. An experimental comparison of these methods was carried out using the base of video recordings obtained in the automatic static perimetry apparatus. On these videos the ground truth tracks of pupil were marked. The comparison was conducted according to two criteria: center location error and tracking length. It is shown that only the weighted average method has an acceptable tracking length.


Ophthalmology ◽  
1993 ◽  
Vol 100 (5) ◽  
pp. 651-659 ◽  
Author(s):  
Dale R. Meyer ◽  
Jeffrey H. Stern ◽  
Janice M. Jarvis ◽  
Lloyd L. Lininger

2020 ◽  
pp. 112067212093767
Author(s):  
Francesco Pellegrini ◽  
Michele Marullo ◽  
Antonio Zappacosta ◽  
Tatiana Liberali ◽  
Alessandra Cuna ◽  
...  

Purpose: To describe a case of a suprasellar meningioma compressing the chiasm from below and producing a unilateral fascicular (nasal) visual field defect that mimicked glaucomatous cupping. Case report: A 78-year-old man presented with painless, progressive, unilateral arcuate visual field defect. He was diagnosed with “normal tension glaucoma” based on an asymmetric cup to disc ratio. Despite treatment with anti-glaucoma drops, the visual field defect progressed. Neurophthalmic evaluation was consistent with a compressive optic neuropathy OD. Brain MRI showed a suprasellar meningioma compressing on the junction of the optic nerve and chiasm from below. Conclusion: Although junctional visual field loss (e.g. junctional scotoma and junctional scotoma of Traquair) are well-known presentations of compressive lesions at the optic chiasm, we describe a monocular, ipsilateral compressive superior nasal defect and asymmetric cupping as the presenting sign of a junctional compressive lesion mimicking glaucomatous cupping.


2018 ◽  
Vol 89 (6) ◽  
pp. A9.1-A9
Author(s):  
Christian J Lueck ◽  
Emily Kane ◽  
David Ashton ◽  
Peter Mews ◽  
Kate Reid ◽  
...  

IntroductionThe exact mechanism that gives rise to bi-temporal hemianopia in chiasmal compression by pituitary tumours is currently unknown. One theory suggests that, because crossing fibres cross each other and therefore have less contact area, they experience greater stress from compressive forces than those experienced by uncrossed fibres (which have a larger contact area). Finite element modelling has been used has been used to investigate this in silico but the hypothesis needs testing in vivo. This study aimed to determine whether extrinsic chiasmal compression was associated with patterns of visual field loss which supported the ‘crossing hypothesis’ or not.MethodsSubjects with chiasmal compression secondary to pituitary tumours who also had clear visual field abnormalities were identified from the Canberra Hospital database. Visual fields were analysed to derive ‘temporality’ and ‘bi-temporality’ indices. MRI scans were analysed to determine the relative elevations of centre and peripheral portions of the optic chiasm and, in turn, the eccentricity of compression. Temporality indices were plotted against central chiasmal elevation, and both temporal and nasal hemi-field abnormalities were plotted against eccentricity.Results122 patients were identified but only 12 were suitable for analysis. Both temporality and bi-temporality indices were significantly correlated with central chiasmal elevation (p=0.004). Hemi-field studies demonstrated patterns of visual loss with increasing eccentricity that were more consistent with the ‘crossing hypothesis’ though the correlations failed to reach significance.ConclusionThis study provides tentative support for the ‘crossing hypothesis’. The information will be used to inform further finite element models of chiasmal compression. A larger, prospective study is warranted.


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