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Eye (London, England) Jun 2024A recent anatomical study of the human optic chiasm cast doubt on the widespread assumption that nerve fibres travelling in the human optic nerve and chiasm are arranged... (Review)
Review
A recent anatomical study of the human optic chiasm cast doubt on the widespread assumption that nerve fibres travelling in the human optic nerve and chiasm are arranged retinotopically. Accordingly, a scoping literature review was performed to determine what is known about the nerve fibre arrangement in these structures. Meta-analysis suggested that the average number of fibres in each optic nerve was 1.023 million with an inter-individual range of approximately 50% of the mean. Loss of nerve fibres with age (approximately 3,400 fibres/year) could not account for this variability. The review suggested that there might be a retinotopic arrangement of nerve fibres in the orbital portion of the optic nerve but that this arrangement is most likely to be lost posteriorly with a more random distribution of nerve fibres at the chiasm. Limited studies have looked at nerve fibre arrangement in the chiasm. In summary, the chiasm is more 'H-shaped' than 'X-shaped': nerve fibre crossings occur paracentrally with nerves in the centre of the chiasm travelling coronally and in parallel. There is interaction between crossed and uncrossed fibres which are widely distributed. The review supports the non-existence of Wilbrand's knee. Considerable further work is required to provide more precise anatomical information, but this review suggests that the assumed preservation of retinotopy in the human optic nerve and chiasm is probably not correct.
PubMed: 38849598
DOI: 10.1038/s41433-024-03137-7 -
Operative Neurosurgery (Hagerstown, Md.) Jun 2024The endoscopic endonasal approach for resection of craniopharyngiomas has gained popularity because of its minimal need for retraction and superior visualization of and...
Use of Real-Time Superior Hypophyseal Artery Indocyanine Green Angiogram During Endoscopic Resection of a Third Ventricular Craniopharyngioma: 2-Dimensional Operative Video.
The endoscopic endonasal approach for resection of craniopharyngiomas has gained popularity because of its minimal need for retraction and superior visualization of and access to the optic chiasm.1-4 Despite these advantages, the proximity of craniopharyngiomas to the optic apparatus still challenges the preservation of visual function.5-10 Indocyanine green (ICG) angiography can evaluate the perfusion of the chiasm and can predict visual outcomes after endonasal approaches, in addition to known uses of the dye.3 ICG angiography may therefore hold promise in the real-time assessment of optic chiasm perfusion during resection of craniopharyngiomas by delineating details of the superior hypophyseal artery (SHA) system. Here, we present a case in which ICG angiogram was used to assess the perfusion of the chiasm before, during, and after tumor resection. This technique signaled thrombosis of the left principal SHA during tumor resection that was compensated by the anastomotic SHA system from the right. The case shows an endoscopic endonasal approach for the resection of a third ventricular craniopharyngioma in a 21-year-old woman presenting with unremitting headaches, endocrine dysfunction, and vision loss. Postoperatively, the patient's neurological examination remained unchanged and visual function improved within 2 weeks. This case underscores the potential for real-time intraoperative ICG angiography to assist in the careful resection of craniopharyngiomas while improving visual outcomes. Institutional review board approval was not required; the patient consented to the procedure and to publishing of the operative video.
PubMed: 38847508
DOI: 10.1227/ons.0000000000001225 -
Child's Nervous System : ChNS :... Jun 2024Visual evoked potential (VEP) is an established modality that allows safe brain tumor resection and preservation of optical function. We herein present a case of a...
Visual evoked potential (VEP) is an established modality that allows safe brain tumor resection and preservation of optical function. We herein present a case of a pediatric craniopharyngioma with significant improvement in the VEP amplitude detected during endoscopic transsphenoidal surgery (ETS) and obvious postoperative improvement in visual acuity. A 13-year-old boy presented with visual acuity disturbance in his right eye and was followed up for 5 months by an ophthalmologist. His visual acuity rapidly worsened, and a suprasellar lesion with calcification was found on brain computed tomography. The patient underwent tumor resection during ETS with intraoperative transcranial VEP monitoring. Gross total tumor resection was achieved without injury to the perforators, including the superior hypophyseal arteries. The VEP amplitude was unstable, and significant waves were not detectable before tumor resection; however, a positive wave was detected after removing most of the tumor and exposing the bilateral optic nerves and optic chiasm. Subsequently, negative and positive VEP waves were continuously detected. Visual acuity improved remarkably on postoperative day 10. This case demonstrated both a significant increase in the intraoperative VEP amplitude and rapid postoperative improvement in visual acuity. We surmised that the preoperative rapid worsening of visual dysfunction, intraoperative increase in the VEP amplitude, and significant postoperative improvement in visual acuity were associated with the compression of the optic nerves by the internal carotid artery, anterior cerebral artery, and tumor.
PubMed: 38842548
DOI: 10.1007/s00381-024-06477-7 -
Frontiers in Surgery 2024Hemangiopericytoma (HPC) constitutes less than 1% of all primary central nervous system tumors. It is a vascular neoplasm with potential malignancy that, in rare...
UNLABELLED
Hemangiopericytoma (HPC) constitutes less than 1% of all primary central nervous system tumors. It is a vascular neoplasm with potential malignancy that, in rare instances, manifests as a primary lesion within the brain. Typically, it originates from the meninges. Here, we describe an exceptionally uncommon sellar region solitary fibrous tumor/hemangiopericytoma (SFT/HPC) that mimicked a nonfunctional pituitary adenoma.
CASE PRESENTATION
A 54-year-old male was referred to our hospital due to progressive blurred vision in the left eye over the past year. A homogeneous iso-dense extra-axial intrasellar round mass with extension into the suprasellar region, mainly on the left side, along with bony erosion and osteolysis around the sellar region, was observed on a brain computed tomography (CT) scan. Brain magnetic resonance imaging (MRI) revealed a well-defined 251,713 mm mass with iso-signal on T1-weighted images and hypersignal on T2-weighted images, originating from the pituitary gland within the sella turcica. The mass avidly enhanced following Gadolinium injection and adhered to both carotid arteries without vascular compression or invasion. It extended to the suprasellar cistern and compressed the optic chiasm. The diagnosis was nonfunctional pituitary macroadenoma, leading to the decision for Endoscopic Trans-Sphenoidal Surgery (ETSS). A non-sustainable, soft, grayish mass was grossly and totally resected during the operation. Subsequently, there was a significant improvement in visual acuity during the early postoperative period. Histopathologic examination confirmed hemangiopericytoma (WHO grade II).
CONCLUSION
Due to its malignant nature, hemangiopericytoma should be included in the differential diagnosis of a sellar mass, both from a clinical and morphological perspective.
PubMed: 38840972
DOI: 10.3389/fsurg.2024.1359787 -
Ophthalmology and Therapy Jul 2024This study investigates how surgery for pituitary adenoma (PA) affects the visual pathway, examining changes in the retina, blood vessel density, and nerve function....
INTRODUCTION
This study investigates how surgery for pituitary adenoma (PA) affects the visual pathway, examining changes in the retina, blood vessel density, and nerve function. Since PAs often impair vision as a result of their location near visual structures, this research is key to understanding and improving vision recovery after surgery.
METHODS
Our study is based on a retrospective analysis of the historical data of 28 patients diagnosed with pituitary adenomas. We conducted assessments by reviewing preoperative and postoperative imaging records. These included optical coherence tomography (OCT) for retinal structure analysis, diffusion tensor imaging (DTI) for neural transmission evaluation, and optical coherence tomography angiography for assessing blood vessel density. These tools allowed for a detailed understanding of the structural and functional changes within the visual pathway following PA surgery.
RESULTS
OCT findings show postoperative changes in the eye: thinning in average and nasal circumpapillary retinal nerve fiber layer, thickening in macular central 1 mm inner plexus layer, ganglion cell complex, and nasal retinal nerve fiber layer. DTI reveals increased fractional anisotropy (FA) in the left optic chiasm and posterior optic nerve, decreased mid-segment optic nerve FA, and increased apparent diffusion coefficient (ADC) in the right optic chiasm and nerve segments. Early postoperative reduction in radial peripapillary capillaries plexus density is noted. Preoperative ganglion cell layer (GCL) thickness correlates with postoperative visual radiation FA and ADC values, especially in the inferior quadrant. A negative correlation exists between preoperative GCL thickness and postoperative visual field mean defect values, particularly on the temporal side and superior inner ring. All changes are statistically significant (P < 0.05).
CONCLUSIONS
The study finds that surgery for PA has varied effects on vision. Early post surgery, there are changes in the retina and nerve signals. Macular GCL thickness before surgery might predict early visual recovery, influencing future research and treatment for vision issues related to PA.
PubMed: 38822193
DOI: 10.1007/s40123-024-00966-3 -
Vision (Basel, Switzerland) May 2024Neurofibromatosis type 1 (NF1) is an inherited autosomal dominant disorder primarily affecting children and adolescents characterized by multisystemic clinical... (Review)
Review
Neurofibromatosis type 1 (NF1) is an inherited autosomal dominant disorder primarily affecting children and adolescents characterized by multisystemic clinical manifestations. Mutations in neurofibromin, the protein encoded by the tumor suppressor gene, result in dysregulation of the RAS/MAPK pathway leading to uncontrolled cell growth and migration. Neurofibromin is highly expressed in several cell lineages including melanocytes, glial cells, neurons, and Schwann cells. Individuals with NF1 possess a genetic predisposition to central nervous system neoplasms, particularly gliomas affecting the visual pathway, known as optic pathway gliomas (OPGs). While OPGs are typically asymptomatic and benign, they can induce visual impairment in some patients. This review provides insight into the spectrum and visual outcomes of NF1, current diagnostic techniques and therapeutic interventions, and explores the influence of NF1-OPGS on visual abnormalities. We focus on recent advancements in preclinical animal models to elucidate the underlying mechanisms of NF1 pathology and therapies targeting NF1-OPGs. Overall, our review highlights the involvement of retinal ganglion cell dysfunction and degeneration in NF1 disease, and the need for further research to transform scientific laboratory discoveries to improved patient outcomes.
PubMed: 38804352
DOI: 10.3390/vision8020031 -
Neuro-ophthalmology (Aeolus Press) 2024Meningeal carcinomatosis (MC) has an extremely poor prognosis and can present with various neurological symptoms. A 68-year-old man presented to our hospital with a...
Meningeal carcinomatosis (MC) has an extremely poor prognosis and can present with various neurological symptoms. A 68-year-old man presented to our hospital with a 1 month history of headache and nausea followed by sudden decrease in vision in both eyes. Whilst being examined in the ophthalmology department he lost consciousness and had a generalised tonic clonic seizure. Accordingly, he was transferred to the Emergency Department. Head magnetic resonance imaging showed hydrocephalus. Abdominal contrast-enhanced computed tomography scanning reported changes suggestive of gastric carcinoma. Cerebrospinal fluid cytological examination showed numerous atypical cells, leading to the diagnosis of MC. An upper gastrointestinal endoscopy revealed an advanced gastric tumour. Systemic chemotherapy was initiated, however, he died within 16 days of admission. At autopsy, poorly differentiated adenocarcinoma was identified in the subarachnoid space, however it had not invaded the brain parenchyma or optic chiasm. This is the first report of loss of vision being the first presenting symptom of new-onset gastric carcinoma with MC. Although rare, MC should be suspected in cases where patients present with sudden loss of vision and symptoms of meningeal irritation, where there are no ophthalmological findings to explain the vision loss.
PubMed: 38756339
DOI: 10.1080/01658107.2023.2290537 -
BMC Medical Genomics May 2024Whole exome sequencing allows rapid identification of causative single nucleotide variants and short insertions/deletions in children with congenital anomalies and/or...
BACKGROUND
Whole exome sequencing allows rapid identification of causative single nucleotide variants and short insertions/deletions in children with congenital anomalies and/or intellectual disability, which aids in accurate diagnosis, prognosis, appropriate therapeutic interventions, and family counselling. Recently, de novo variants in the MED13 gene were described in patients with an intellectual developmental disorder that included global developmental delay, mild congenital heart anomalies, and hearing and vision problems in some patients.
RESULTS
Here we describe an infant who carried a de novo p.Pro835Ser missense variant in the MED13 gene, according to whole exome trio sequencing. He presented with congenital heart anomalies, dysmorphic features, hydrocephalic changes, hypoplastic corpus callosum, bilateral optic nerve atrophy, optic chiasm atrophy, brain stem atrophy, and overall a more severe condition compared to previously described patients.
CONCLUSIONS
Therefore, we propose to expand the MED13-associated phenotype to include severe complications that could end up with multiple organ failure and neonatal death.
Topics: Humans; Mutation, Missense; Male; Phenotype; Mediator Complex; Abnormalities, Multiple; Infant; Infant, Newborn; Syndrome; Exome Sequencing
PubMed: 38745205
DOI: 10.1186/s12920-024-01857-z -
Neuroradiology Jul 2024Morning glory disc anomaly (MGDA) is a rare congenital ophthalmologic disorder. Historically it has been diagnosed fundoscopically, with little in the literature...
PURPOSE
Morning glory disc anomaly (MGDA) is a rare congenital ophthalmologic disorder. Historically it has been diagnosed fundoscopically, with little in the literature regarding its imaging findings. The purpose of this study is to further characterize the orbital and associated intracranial magnetic resonance imaging (MRI) findings of MGDA in our tertiary pediatric center.
METHODS
A retrospective review was performed of fundoscopically-diagnosed cases of MGDA, that had been referred for MRI. All MRI studies were scrutinized for orbital and other intracranial abnormalities known to occur in association with MGDA.
RESULTS
18 of 19 cases of MGDA showed three characteristic MRI findings: funnel-shaped morphology of the posterior optic disc, abnormal soft tissue associated with the retrobulbar optic nerve, and effacement of adjacent subarachnoid spaces. The ipsilateral (intraorbital) optic nerve was larger in one patient and smaller in six. The ipsilateral optic chiasm was larger in two patients and smaller in one.
CONCLUSION
This study represents a comprehensive radiological-led investigation into MGDA. It describes the most frequently-encountered MRI findings in MGDA and emphasizes the importance of MRI in this cohort, i.e., in distinguishing MGDA from other posterior globe abnormalities, in assessing the visual pathway, and in screening for associated intracranial abnormalities - skull base/cerebral, vascular, and facial. It hypothesizes neurocristopathy as an underlying cause of MGDA and its associations. Caliber abnormalities of the ipsilateral optic nerve and chiasm are a frequent finding in MGDA. Optic pathway enlargement should not be labeled "glioma". (239/250).
Topics: Humans; Male; Female; Magnetic Resonance Imaging; Retrospective Studies; Child; Optic Disk; Child, Preschool; Infant; Adolescent; Eye Abnormalities
PubMed: 38717474
DOI: 10.1007/s00234-024-03375-2 -
SAGE Open Medical Case Reports 2024Herein, we report a rare case of invasive nasopharyngeal carcinoma with extension to the pituitary gland misdiagnosed as a pituitary macroadenoma. A 50-year-old woman...
Herein, we report a rare case of invasive nasopharyngeal carcinoma with extension to the pituitary gland misdiagnosed as a pituitary macroadenoma. A 50-year-old woman was referred to our department with a diagnosis of pituitary macroadenoma. She presented with headache, visual disturbances, weakness, nausea, vomiting, and hypoglycemia. Polyuria was not reported. On pituitary magnetic resonance imaging, a large mass was observed to extend from the sella turcica to the sphenoid sinus, optic chiasm, and nasopharynx, leading to the initial diagnosis of an invasive pituitary macroadenoma. Biochemical investigations revealed corticotropin deficiency, secondary hypothyroidism, hypogonadotropic hypogonadism, and moderate hyperprolactinemia. Hormone replacement therapy was initiated. After hydrocortisone initiation, diabetes insipidus was revealed. Subsequent magnetic resonance imaging showed an infiltration of the nasopharynx with an extension to the pituitary gland. An endoscopic biopsy confirmed the diagnosis of undifferentiated nasopharyngeal carcinoma. The patient was referred to the oncology department for chemo and radiotherapy. Invasive nasopharyngeal carcinoma presenting with pituitary extension is very rare. It should be considered in the differential diagnosis of pituitary macroadenoma with hypopituitarism. Proper management of such cases requires a multidisciplinary approach.
PubMed: 38715901
DOI: 10.1177/2050313X241252337