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The Journal of Craniofacial Surgery Jan 2024This paper determined the morphometric measurements' reference values and relationship of the optic nerve and cranium in Turkish healthy individuals according to age and...
This paper determined the morphometric measurements' reference values and relationship of the optic nerve and cranium in Turkish healthy individuals according to age and sex. Five hundred fifty-nine (280 females and 279 males) patients aged from 2 to 90 years were included in this study. The measurements were taken from patients having brain magnetic resonance images in sagittal, axial, and coronal sections in the radiology department. Eyeball transverse diameter, optic nerve sheath thickness (ONST), optic chiasm length, optic chiasm width, and cranium morphometric measurements of all individuals who participated in the study were taken. Except for the width of the optic chiasm, all measurements showed significant differences between the sexes (P < 0.05). In contrast, all measurement values were higher in males than females, except for the clival angle. According to the result of Pearson correlation analysis, in which the existence of a relationship between ONST and craniometric measurements was evaluated, a low but significant correlation was found between ONST and craniometric measurements (r < 0.4; P < 0.05). In the post hoc test performed to compare the decades, it was seen that the most significant changes in our measurements were in the 2 to 10 age range and the measurement values decreased in old age. We think that revealing the age and sex-related changes in the optic nerve and cranium morphometry of our population anatomically and radiologically will be an important source in terms of creating reference values for our population.
PubMed: 38284899
DOI: 10.1097/SCS.0000000000009972 -
Asian Journal of Surgery Feb 2024
Topics: Humans; Optic Chiasm; Optic Nerve; Foot; Lower Extremity
PubMed: 37945403
DOI: 10.1016/j.asjsur.2023.10.090 -
Pediatric Radiology Sep 2023Alexander disease is a leukodystrophy caused by mutations in the GFAP gene, primarily affecting the astrocytes. This report describes the prenatal and post-mortem...
Alexander disease is a leukodystrophy caused by mutations in the GFAP gene, primarily affecting the astrocytes. This report describes the prenatal and post-mortem neuroimaging findings in a case of genetically confirmed, fetal-onset Alexander disease with pathological correlation after termination of pregnancy. The additional value of fetal brain magnetic resonance imaging in the third trimester as a complementary evaluation tool to neurosonography is shown for suspected cases of fetal-onset Alexander disease. Diffuse signal abnormalities of the periventricular white matter in association with thickening of the fornix and optic chiasm can point towards the diagnosis. Furthermore, the presence of atypical imaging findings such as microcephaly and cortical folding abnormalities in this case broadens our understanding of the phenotypic variability of Alexander disease.
Topics: Pregnancy; Female; Humans; Alexander Disease; Glial Fibrillary Acidic Protein; Cerebral Ventricles; Radiography; Mutation; Magnetic Resonance Imaging
PubMed: 37455276
DOI: 10.1007/s00247-023-05710-w -
The Neuroradiology Journal Nov 2023Abnormal development of the posterior pituitary gland can lead to an ectopic location of the neurohypophysis, commonly seen at the median eminence of the hypothalamus or...
Abnormal development of the posterior pituitary gland can lead to an ectopic location of the neurohypophysis, commonly seen at the median eminence of the hypothalamus or along the infundibular stalk. A partial ectopic posterior pituitary (PEPP) is a very rare variant of the ectopic posterior pituitary, defined as the presence of a double bright spot of neurohypophysis seen in both orthotopic and ectopic locations. We report a two-year-old male toddler with bilateral optic nerve hypoplasia and severe visual impairment who presented to the endocrine outpatient clinic for hypopituitarism evaluation. Magnetic resonance imaging (MRI) of the brain revealed a hypoplastic pituitary gland and infundibulum with a double bright spot of neurohypophysis in the expected normal location and along the median eminence. Severe hypoplasia of both optic nerves and the optic chiasm was also seen. Septum pellucidum was present with no evidence of other brain malformations. The findings are in the septo-optic dysplasia spectrum associated with hypothalamic-pituitary dysfunction and a very rare entity called PEPP. To our knowledge, only a handful of reported cases of this rare entity exist in the literature.
PubMed: 37920914
DOI: 10.1177/19714009231212369 -
Journal of Neuro-ophthalmology : the... Mar 2024
Topics: Humans; Optic Nerve; Optic Chiasm
PubMed: 38170604
DOI: 10.1097/WNO.0000000000002071 -
European Radiology Nov 2023We conducted a systematic review and individual participant data meta-analysis of publications reporting the ophthalmologic presentation, clinical exam, and orbital MRI... (Meta-Analysis)
Meta-Analysis
OBJECTIVES
We conducted a systematic review and individual participant data meta-analysis of publications reporting the ophthalmologic presentation, clinical exam, and orbital MRI findings in patients with giant cell arteritis and ocular manifestations.
METHODS
PubMed and Cochrane databases were searched up to January 16, 2022. Publications reporting patient-level data on patients with ophthalmologic symptoms, imaged with orbital MRI, and diagnosed with biopsy-proven giant cell arteritis were included. Demographics, clinical symptoms, exam, lab, imaging, and outcomes data were extracted. The methodological quality and completeness of reporting of case reports were assessed.
RESULTS
Thirty-two studies were included comprising 51 patients (females = 24; median age, 76 years). Vision loss (78%) and headache (45%) were commonly reported visual and cranial symptoms. Ophthalmologic presentation was unilateral (41%) or bilateral (59%). Fundus examination most commonly showed disc edema (64%) and pallor (49%). Average visual acuity was very poor (2.28 logMAR ± 2.18). Diagnoses included anterior (61%) and posterior (16%) ischemic optic neuropathy, central retinal artery occlusion (8%), and orbital infarction syndrome (2%). On MRI, enhancement of the optic nerve sheath (53%), intraconal fat (25%), and optic nerve/chiasm (14%) was most prevalent. Among patients with monocular visual symptoms, 38% showed pathologic enhancement in the asymptomatic orbit. Six of seven cases reported imaging resolution after treatment on follow-up MRIs.
CONCLUSIONS
Vision loss, pallid disc edema, and optic nerve sheath enhancement are the most common clinical, fundoscopic, and imaging findings reported in patients diagnosed with giant cell arteritis with ocular manifestations, respectively. MRI may detect subclinical inflammation and ischemia in the asymptomatic eye and may be an adjunct diagnostic tool.
CLINICAL RELEVANCE STATEMENT
Brain and orbital MRIs may have diagnostic and prognostic roles in patients with suspected giant cell arteritis who present with ophthalmic symptoms.
Topics: Female; Humans; Aged; Giant Cell Arteritis; Vision Disorders; Magnetic Resonance Imaging; Optic Neuropathy, Ischemic; Edema
PubMed: 37256352
DOI: 10.1007/s00330-023-09770-2 -
European Radiology Nov 2023To investigate whether morphological changes after surgery and delta-radiomics of the optic chiasm obtained from routine MRI could help predict postoperative visual...
OBJECTIVES
To investigate whether morphological changes after surgery and delta-radiomics of the optic chiasm obtained from routine MRI could help predict postoperative visual recovery of pituitary adenoma patients.
METHODS
A total of 130 pituitary adenoma patients were retrospectively enrolled and divided into the recovery group (n = 87) and non-recovery group (n = 43) according to visual outcome 1 year after endoscopic endonasal transsphenoidal surgery. Morphological parameters of the optic chiasm were measured preoperatively and postoperatively, including chiasmal thickness, deformed angle, and suprasellar extension. Delta-radiomics of the optic chiasm were calculated based on features extracted from preoperative and postoperative coronal T2-weighted images, followed by machine learning modeling using least absolute shrinkage and selection operator wrapped with support vector machine through fivefold cross-validation in the development set. The delta-radiomic model was independently evaluated in the test set, and compared with the combined model that incorporated delta-radiomics, significant clinical and morphological parameters.
RESULTS
Postoperative morphological changes of the optic chiasm could not significantly be used as predictors for the visual outcome. In contrast, the delta-radiomics model represented good performances in predicting visual recovery, with an AUC of 0.821 in the development set and 0.811 in the independent test set. Moreover, the combined model that incorporated age and delta-radiomics features of the optic chiasm achieved the highest AUC of 0.841 and 0.840 in the development set and independent test set, respectively.
CONCLUSIONS
Our proposed machine learning models based on delta-radiomics of the optic chiasm can be used to predict postoperative visual recovery of pituitary adenoma patients.
CLINICAL RELEVANCE STATEMENT
Our delta-radiomics-based models from MRI enable accurate visual recovery predictions in pituitary adenoma patients who underwent endoscopic endonasal transsphenoidal surgery, facilitating better clinical decision-making and ultimately improving patient outcomes.
KEY POINTS
• Prediction of the postoperative visual outcome for pituitary adenoma patients is important but challenging. • Delta-radiomics of the optic chiasm after surgical decompression represented better prognostic performances compared with its morphological changes. • The proposed machine learning models can serve as novel approaches to predict visual recovery for pituitary adenoma patients in clinical practice.
Topics: Humans; Pituitary Neoplasms; Optic Chiasm; Retrospective Studies; Magnetic Resonance Imaging; Prognosis; Adenoma
PubMed: 37488296
DOI: 10.1007/s00330-023-09963-9 -
Investigative Ophthalmology & Visual... Oct 2023Albinism is a congenital disorder affecting pigmentation levels, structure, and function of the visual system. The identification of anatomical changes typical for...
PURPOSE
Albinism is a congenital disorder affecting pigmentation levels, structure, and function of the visual system. The identification of anatomical changes typical for people with albinism (PWA), such as optic chiasm malformations, could become an important component of diagnostics. Here, we tested an application of convolutional neural networks (CNNs) for this purpose.
METHODS
We established and evaluated a CNN, referred to as CHIASM-Net, for the detection of chiasmal malformations from anatomic magnetic resonance (MR) images of the brain. CHIASM-Net, composed of encoding and classification modules, was developed using MR images of controls (n = 1708) and PWA (n = 32). Evaluation involved 8-fold cross validation involving accuracy, precision, recall, and F1-score metrics and was performed on a subset of controls and PWA samples excluded from the training. In addition to quantitative metrics, we used Explainable AI (XAI) methods that granted insights into factors driving the predictions of CHIASM-Net.
RESULTS
The results for the scenario indicated an accuracy of 85 ± 14%, precision of 90 ± 14% and recall of 81 ± 18%. XAI methods revealed that the predictions of CHIASM-Net are driven by optic-chiasm white matter and by the optic tracts.
CONCLUSIONS
CHIASM-Net was demonstrated to use relevant regions of the optic chiasm for albinism detection from magnetic resonance imaging (MRI) brain anatomies. This indicates the strong potential of CNN-based approaches for visual pathway analysis and ultimately diagnostics.
Topics: Humans; Optic Chiasm; Artificial Intelligence; Visual Pathways; Albinism; Magnetic Resonance Imaging
PubMed: 37815506
DOI: 10.1167/iovs.64.13.14 -
Investigative Ophthalmology & Visual... Nov 2023Perception of the motion quartet (MQ) alternates between horizontal and vertical motion, with a bias toward vertical motion. This vertical bias has been explained by the...
PURPOSE
Perception of the motion quartet (MQ) alternates between horizontal and vertical motion, with a bias toward vertical motion. This vertical bias has been explained by the dominance of intrahemispheric processing. In albinism, each hemisphere receives input from both visual hemifields owing to enhanced crossing of the optic nerves at the optic chiasm. This might affect the perception of the ambiguous MQ and particularly the vertical bias.
METHODS
The effect of optic nerve misrouting in persons with albinism and nystagmus (PWA, n = 14) on motion perception for MQ was compared with healthy controls (HC; n = 11) and with persons with nystagmus in the absence of optic nerve misrouting (PWN; n = 12). We varied the ratio of horizontal and vertical distances of MQ dots (aspect ratio [AR]) between 0.75 and 1.25 and compared the percentages of horizontal and vertical motion percepts as a function of AR between groups.
RESULTS
For HC, the probability of vertical motion perception increased as a sigmoid function with increasing AR exhibiting the expected vertical percept bias (mean, 58%; median, 54%; vertical motion percepts). PWA showed a surprisingly strong horizontal bias independent of the AR with a mean of 11% (median, 10%) vertical motion percepts. The PWN was in between PWA and HC, with a mean of 34% (median, 47%) vertical perception. Nystagmus alone is unlikely to explain this pattern of results because PWA and PWN had comparable fixation stabilities.
CONCLUSIONS
The strong horizontal bias observed in PWA and PWN might partly result from the horizontal nystagmus. The even stronger horizontal bias in PWA indicates that the intrahemispherical corepresentation of both visual hemifields may play an additional role. The altered perception of the MQ in PWA opens opportunities to (i) understand the interplay of stability and plasticity in altered visual pathway conditions and (ii) identify visual pathway abnormalities with a perception-based test using the MQ.
Topics: Humans; Albinism; Motion Perception; Nystagmus, Pathologic; Optic Chiasm; Optic Nerve
PubMed: 38015177
DOI: 10.1167/iovs.64.14.39 -
Journal of Veterinary Diagnostic... Mar 2024A 26-y-old, male, captive Humboldt penguin () was euthanized following a 3.5-mo history of weakened elimination mechanics, recurrent tenesmus, intermittent hemorrhagic...
A 26-y-old, male, captive Humboldt penguin () was euthanized following a 3.5-mo history of weakened elimination mechanics, recurrent tenesmus, intermittent hemorrhagic droppings, and a cloacal mass. Blepharospasm, of unknown cause, of the right eye was present for ~3 mo before euthanasia. Autopsy revealed a cloacal adenocarcinoma with localized coelomic carcinomatosis and distant metastases to the liver and lungs. On histopathology, a 2.6 × 1.2 × 0.5-mm, well-demarcated mass was found surrounding the right optic nerve, expanding the subdural space and wrapping the leptomeninges. The mass was composed of neoplastic spindle-to-polygonal cells consistent with a meningioma, meningothelial subtype. No evidence of neoplasia was found in the optic chiasm or brain, indicating a primary retrobulbar meningioma. Immunohistochemistry for cytokeratin AE1/AE3, vimentin, and S100 revealed robust and consistent immunoreactivity to vimentin, and weak and variable immunoreactivity to cytokeratin and S100, supporting the diagnosis. Meningiomas have been described only rarely in avian species, and we found no reports of optic nerve meningiomas in any avian species to date. The optic nerve meningioma in this case was considered a clinically incidental finding.
Topics: Male; Animals; Meningioma; Spheniscidae; Vimentin; Adenocarcinoma; Optic Nerve; Meningeal Neoplasms; Keratins
PubMed: 38212884
DOI: 10.1177/10406387231225651