019 Correlation of visual field loss with mri findings in patients with pituitary tumours

2018 ◽  
Vol 89 (6) ◽  
pp. A9.1-A9
Author(s):  
Christian J Lueck ◽  
Emily Kane ◽  
David Ashton ◽  
Peter Mews ◽  
Kate Reid ◽  
...  
Keyword(s):  
Finite Element ◽  
Visual Field ◽  
Contact Area ◽  
Visual Fields ◽  
Visual Field Loss ◽  
Optic Chiasm ◽  
Pituitary Tumours ◽  
Mri Findings ◽  
Chiasmal Compression

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.

Long-term visual outcome after microsurgical removal of occipital lobe cavernomas

2012 ◽  
Vol 117 (2) ◽  
pp. 295-301 ◽  
Author(s):  
Juri Kivelev ◽  
Elina Koskela ◽  
Kirsi Setälä ◽  
Mika Niemelä ◽  
Juha Hernesniemi
Keyword(s):  
Visual Field ◽  
Visual Fields ◽  
Visual Field Loss ◽  
Occipital Lobe ◽  
Visual Outcome ◽  
Surgical Removal ◽  
Long Term Outcome ◽  
Visual Field Deficit

Object Cavernomas in the occipital lobe are relatively rare. Because of the proximity to the visual cortex and incoming subcortical tracts, microsurgical removal of occipital cavernomas may be associated with a risk of visual field defects. The goal of the study was to analyze long-term outcome after operative treatment of occipital cavernomas with special emphasis on visual outcome. Methods Of the 390 consecutive patients with cavernomas who were treated at Helsinki University Central Hospital between 1980 and 2011, 19 (5%) had occipital cavernomas. Sixteen patients (4%) were surgically treated and are included in this study. The median age was 39 years (range 3–59 years). Seven patients (56%) suffered from hemorrhage preoperatively, 5 (31%) presented with visual field deficits, 11 (69%) suffered from seizures, and 4 (25%) had multiple cavernomas. Surgery was indicated for progressive neurological deterioration. The median follow-up after surgery was 5.25 years (range 0.5–14 years). Results All patients underwent thorough neuroophthalmological assessment to determine visual outcome after surgery. Visual fields were classified as normal, mild homonymous visual field loss (not disturbing the patient, driving allowed), moderate homonymous visual field loss (disturbing the patient, driving prohibited), and severe visual field loss (total homonymous hemianopia or total homonymous quadrantanopia). At the last follow-up, 4 patients (25%) had normal visual fields, 6 (38%) had a mild visual field deficit, 1 (6%) complained of moderate visual field impairment, and 5 (31%) had severe homonymous visual field loss. Cavernomas seated deeper than 2 cm from the pial surface carried a 4.4-fold risk of postoperative visual field deficit relative to superficial ones (p = 0.034). Six (55%) of the 11 patients presenting with seizures were seizure-free postoperatively. Eleven (69%) of 16 patients had no disability during the long-term follow-up. Conclusions Surgical removal of occipital cavernomas may carry a significant risk of postoperative visual field deficit, and the risk is even higher for deeper lesions. Seizure outcome after removal of these cavernomas appeared to be worse than that after removal in other supratentorial locations. This should be taken into account during preoperative planning.

The variation of resolution and of ommatidial dimensions in the compound eyes of the fiddler crab Uca lactea annulipes (Ocypodidae, Brachyura, Decapoda)

1996 ◽  
Vol 199 (7) ◽  
pp. 1569-1577 ◽  
Author(s):  
J Zeil ◽  
M Al-Mutairi
Keyword(s):  
Visual Field ◽  
Fiddler Crab ◽  
Visual Fields ◽  
Horizontal Resolution ◽  
Resolving Power ◽  
Compound Eyes ◽  
Vertical Resolution ◽  
Histological Techniques ◽  
Uca Lactea

We studied variations in the optical properties of the compound eyes of Uca lactea annulipes using in vivo optical and histological techniques. The distribution of resolving power in the eyes of this fiddler crab species is typical for arthropods that inhabit flat environments: the eyes possess a panoramic equatorial acute zone for vertical resolution and a steep decrease of resolution away from the eye equator in the dorsal and ventral visual fields. The dimensions of the cellular components of the ommatidia vary accordingly: in the equatorial part of the eyes, facets are larger, and crystalline cones and rhabdoms are longer than in the dorsal and ventral parts of the eyes. Along the eye equator, horizontal resolution is low compared with vertical resolution and varies little throughout the visual field. The eyes of Uca lactea annulipes are unusual in that the gradient of vertical anatomical and optical resolution is steeper in the dorsal than in the ventral visual field. We interpret this difference as indicating that the information content of the world as seen by the crabs differs above and below the horizon line in specific and predictable ways.

scholarly journals Estimating Rates of Progression and Predicting Future Visual Fields in Glaucoma Using a Deep Variational Autoencoder

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Samuel I. Berchuck ◽  
Sayan Mukherjee ◽  
Felipe A. Medeiros
Keyword(s):  
Visual Field ◽  
Learning Algorithm ◽  
Visual Fields ◽  
Visual Field Loss ◽  
Absolute Error ◽  
Rate Of Change ◽  
Mean Deviation ◽  
Automated Perimetry ◽  
Standard Automated Perimetry ◽  
Deep Learning Algorithm

AbstractIn this manuscript we develop a deep learning algorithm to improve estimation of rates of progression and prediction of future patterns of visual field loss in glaucoma. A generalized variational auto-encoder (VAE) was trained to learn a low-dimensional representation of standard automated perimetry (SAP) visual fields using 29,161 fields from 3,832 patients. The VAE was trained on a 90% sample of the data, with randomization at the patient level. Using the remaining 10%, rates of progression and predictions were generated, with comparisons to SAP mean deviation (MD) rates and point-wise (PW) regression predictions, respectively. The longitudinal rate of change through the VAE latent space (e.g., with eight dimensions) detected a significantly higher proportion of progression than MD at two (25% vs. 9%) and four (35% vs 15%) years from baseline. Early on, VAE improved prediction over PW, with significantly smaller mean absolute error in predicting the 4th, 6th and 8th visits from the first three (e.g., visit eight: VAE8: 5.14 dB vs. PW: 8.07 dB; P < 0.001). A deep VAE can be used for assessing both rates and trajectories of progression in glaucoma, with the additional benefit of being a generative technique capable of predicting future patterns of visual field damage.

scholarly journals Subject-Specific Finite Element Modeling of the Tibiofemoral Joint Based on CT, Magnetic Resonance Imaging and Dynamic Stereo-Radiography Data in Vivo

2014 ◽  
Vol 136 (4) ◽  
Author(s):  
Robert E. Carey ◽  
Liying Zheng ◽  
Ameet K. Aiyangar ◽  
Christopher D. Harner ◽  
Xudong Zhang
Keyword(s):  
Magnetic Resonance Imaging ◽  
Finite Element ◽  
Magnetic Resonance ◽  
Contact Area ◽  
Resonance Imaging ◽  
Model Predictions ◽  
Subject Specific ◽  
Skeletal Kinematics ◽  
Tibiofemoral Kinematics

In this paper, we present a new methodology for subject-specific finite element modeling of the tibiofemoral joint based on in vivo computed tomography (CT), magnetic resonance imaging (MRI), and dynamic stereo-radiography (DSX) data. We implemented and compared two techniques to incorporate in vivo skeletal kinematics as boundary conditions: one used MRI-measured tibiofemoral kinematics in a nonweight-bearing supine position and allowed five degrees of freedom (excluding flexion-extension) at the joint in response to an axially applied force; the other used DSX-measured tibiofemoral kinematics in a weight-bearing standing position and permitted only axial translation in response to the same force. Verification and comparison of the model predictions employed data from a meniscus transplantation study subject with a meniscectomized and an intact knee. The model-predicted cartilage-cartilage contact areas were examined against “benchmarks” from a novel in situ contact area analysis (ISCAA) in which the intersection volume between nondeformed femoral and tibial cartilage was characterized to determine the contact. The results showed that the DSX-based model predicted contact areas in close alignment with the benchmarks, and outperformed the MRI-based model: the contact centroid predicted by the former was on average 85% closer to the benchmark location. The DSX-based FE model predictions also indicated that the (lateral) meniscectomy increased the contact area in the lateral compartment and increased the maximum contact pressure and maximum compressive stress in both compartments. We discuss the importance of accurate, task-specific skeletal kinematics in subject-specific FE modeling, along with the effects of simplifying assumptions and limitations.

scholarly journals Novel Pathogenic Sequence Variants in NR2E3 and Clinical Findings in Three Patients

Genes ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1288
Author(s):  
Saoud Al-khuzaei ◽  
Suzanne Broadgate ◽  
Stephanie Halford ◽  
Jasleen K. Jolly ◽  
Morag Shanks ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Visual Fields ◽  
Visual Field Loss ◽  
Clinical Findings ◽  
Sequence Variants ◽  
Childhood Onset ◽  
Distinctive Features ◽  
Targeted Ngs ◽  
Clinical Records

A retrospective review of the clinical records of patients seen at the Oxford Eye Hospital identified as having NR2E3 mutations was performed. The data included symptoms, best-corrected visual acuity, multimodal retinal imaging, visual fields and electrophysiology testing. Three participants were identified with biallelic NR2E3 pathogenic sequence variants detected using a targeted NGS gene panel, two of which were novel. Participant I was a Nepalese male aged 68 years, and participants II and III were white Caucasian females aged 69 and 10 years old, respectively. All three had childhood onset nyctalopia, a progressive decrease in central vision, and visual field loss. Patients I and III had photopsia, patient II had photosensitivity and patient III also had photophobia. Visual acuities in patients I and II were preserved even into the seventh decade, with the worst visual acuity measured at 6/36. Visual field constriction was severe in participant I, less so in II, and fields were full to bright targets targets in participant III. Electrophysiology testing in all three demonstrated loss of rod function. The three patients share some of the typical distinctive features of NR2E3 retinopathies, as well as a novel clinical observation of foveal ellipsoid thickening.

Correlation of MRI Findings With Patterns of Visual Field Loss in Patients With Pituitary Tumors

2019 ◽  
Vol 39 (3) ◽  
pp. 333-338 ◽  
Author(s):  
Emily J. Kane ◽  
David E. Ashton ◽  
Peter J. Mews ◽  
Kate Reid ◽  
Andrew Neely ◽  
...  
Keyword(s):  
Visual Field ◽  
Pituitary Tumors ◽  
Visual Field Loss ◽  
Mri Findings

scholarly journals Comparison of Diagnostic Accuracy between Octopus 900 and Goldmann Kinetic Visual Fields

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Fiona J. Rowe ◽  
Alison Rowlands
Keyword(s):  
Visual Field ◽  
Diagnostic Accuracy ◽  
Visual Fields ◽  
Visual Field Loss ◽  
Area Measurement ◽  
Test Duration ◽  
Bonferroni Adjustment ◽  
Goldmann Perimetry ◽  
Field Defect ◽  
Octopus Perimetry

Purpose. To determine diagnostic accuracy of kinetic visual field assessment by Octopus 900 perimetry compared with Goldmann perimetry.Methods. Prospective cross section evaluation of 40 control subjects with full visual fields and 50 patients with known visual field loss. Comparison of test duration and area measurement of isopters for Octopus 3, 5, and 10°/sec stimulus speeds. Comparison of test duration and type of visual field classification for Octopus versus Goldmann perimetry. Results were independently graded for presence/absence of field defect and for type and location of defect. Statistical evaluation comprised of ANOVA and paired t test for evaluation of parametric data with Bonferroni adjustment. Bland Altman and Kappa tests were used for measurement of agreement between data.Results. Octopus 5°/sec perimetry had comparable test duration to Goldmann perimetry. Octopus perimetry reliably detected type and location of visual field loss with visual fields matched to Goldmann results in 88.8% of results(K=0.775).Conclusions. Kinetic perimetry requires individual tailoring to ensure accuracy. Octopus perimetry was reproducible for presence/absence of visual field defect. Our screening protocol when using Octopus perimetry is 5°/sec for determining boundaries of peripheral isopters and 3°/sec for blind spot mapping with further evaluation of area of field loss for defect depth and size.

scholarly journals Visual disturbance as primary symptom of pituitary apoplexy in pregnancy

2021 ◽  
Vol 3 (4) ◽  
pp. 244-249
Author(s):  
Norazlida Ibrahim ◽  
Raja Norliza Binti Raja Omar ◽  
Mae-Lynn Catherine Bastion
Keyword(s):  
Visual Field ◽  
Pituitary Apoplexy ◽  
Wide Spectrum ◽  
Brain Mri ◽  
Visual Field Loss ◽  
Optic Chiasm ◽  
Visual Disturbance ◽  
Mortality And Morbidity ◽  
Pituitary Lesion ◽  
In Pregnancy

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.

scholarly journals In Vivo anterior Optic Nerve Head changes as a function of Visual Field loss in Glaucoma

2019 ◽  
Vol 97 (S263) ◽  
Author(s):  
Ryan Lee Bartlett ◽  
Bethany E Frost ◽  
Nick White ◽  
James R Fergusson ◽  
James E Morgan ◽  
...  
Keyword(s):  
Optic Nerve ◽  
Visual Field ◽  
Optic Nerve Head ◽  
Visual Field Loss

Scleral Buckling versus Vitrectomy for Retinal Detachment Repair: Comparison of Visual Fields and Nerve Fiber Layer Thickness

2015 ◽  
Vol 235 (1) ◽  
pp. 10-17 ◽  
Author(s):  
Chryssanthi Koutsandrea ◽  
Menelaos Kanakis ◽  
Dimitrios Papaconstantinou ◽  
Dimitrios Brouzas ◽  
Ioannis Ladas ◽  
...  
Keyword(s):  
Visual Field ◽  
Retinal Detachment ◽  
Nerve Fiber ◽  
Visual Fields ◽  
Visual Field Loss ◽  
Scleral Buckling ◽  
Fiber Layer ◽  
Mean Values ◽  
Nerve Fiber Layer ◽  
Significant Difference

Purpose: To compare visual field loss and retinal nerve fiber layer (RNFL) defects in cases of rhegmatogenous retinal detachment (RRD) treated with scleral buckle (SB) versus pars plana vitrectomy (PPV) and C3F8 injection. Methods: This was a prospective, comparative interventional study of 50 eyes with primary RRD, treated with PPV (25 eyes) or SB (25 eyes). All measurements took place at least 9 months following successful and uncomplicated surgical treatment. The visual field total deviation (TD) values for preoperative attached and detached areas were calculated and compared separately. The optic nerve head morphology was studied with Heidelberg retinal tomography (HRT), and the RNFL using spectral-domain optical coherence tomography. Results: The preoperative detached areas demonstrated more affected TD values (in dB) compared to the preoperative attached areas (-6.9 ± 5.2 vs. -4.3 ± 3.3 for the SB group and -9.6 ± 5.2 vs. -7.8 ± 5.1 for the PPV group; p = 0.001) in both groups. The preoperative attached areas of the SB group showed better TD values (calculated mean values) compared to the preoperative attached areas of the PPV group (-4.3 ± 3.3 vs. -7.8 ± 5.1, p = 0.007). The RNFL and HRT values showed no statistically significant difference between the two groups. Conclusions: It seems that the preoperative detached retina, despite successful reattachment, suffers permanent damage as a result of the detachment, irrespective of the method of treatment. In the PPV group, the postoperative functionality of the preoperative attached areas was detected to be worse compared to the postoperative functionality of the preoperative attached areas of the SB group. We postulate that this fact could be attributed to an additional traumatizing factor (possibly fluid-air exchange or gas injection) in patients with RRD treated with PPV.

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