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Clinical Neurology and Neurosurgery Jan 2023Microsurgical treatment of ophthalmic segment aneurysms often requires anterior clinoidectomy and optic nerve mobilization prior to successful clipping.
BACKGROUND
Microsurgical treatment of ophthalmic segment aneurysms often requires anterior clinoidectomy and optic nerve mobilization prior to successful clipping.
OBJECTIVE
We hypothesize that ophthalmic segment aneurysms that are elongated and finger-like grow unconstrained, lateral to the optic nerve. We note that this avoids the need for clinoid resection and optic nerve mobilization.
METHODS
Three cases with up-pointing aneurysms were reviewed. Patient and aneurysm characteristics were collected.
RESULTS
The first two patients with elongated ophthalmic segment aneurysms were found to have aneurysms growing lateral to the optic nerve. This allowed for straightforward treatment via microsurgical clipping without anterior clinoidectomy or division of the falciform ligament. The third patient presented with distortion of the optic chiasm superiorly and medially by a giant ventral ICA aneurysm. A concomitant ophthalmic aneurysm in this patient exhibited elongated morphology, with a high-resolution MRI demonstrating the patient's optic nerve was located inferior and medial to the ophthalmic artery aneurysm dome. This supports our hypothesis that an overriding optic nerve normally impedes vertical growth of ophthalmic segment aneurysms.
CONCLUSIONS
Ophthalmic segment aneurysms may acquire a round morphology when their growth is constrained superiorly by the optic nerve. Elongated ophthalmic segment aneurysms may be the result of growth lateral to the optic nerve. For these aneurysms, an anterior clinoidectomy is not required, and microsurgical clipping represents a straightforward treatment option.
Topics: Humans; Intracranial Aneurysm; Ophthalmic Artery; Optic Nerve; Optic Chiasm; Neurosurgical Procedures; Carotid Artery, Internal
PubMed: 36495621
DOI: 10.1016/j.clineuro.2022.107546 -
Multiple Sclerosis (Houndmills,... Jan 2022Optic neuritis (ON) is often the presenting symptom in inflammatory central nervous system demyelinating disorders.
BACKGROUND
Optic neuritis (ON) is often the presenting symptom in inflammatory central nervous system demyelinating disorders.
OBJECTIVE
To compare the frequency and pattern of optic chiasm involvement in patients with aquaporin-4-immunoglobulin G (AQP4-IgG)-associated ON to patients with myelin oligodendrocyte glycoprotein-immunoglobulin G (MOG-IgG)-associated ON.
METHODS
Retrospective review of all patients evaluated at Mayo Clinic, Stanford University and Ramathibodi Hospital who were found to have: (1) ON, (2) either MOG-IgG or AQP4-IgG by cell-based assay, and (3) magnetic resonance imaging (MRI) at the time of ON. MRI was reviewed for contrast enhancement of the optic chiasm and the pattern of involvement.
RESULTS
One hundred and fifty-four patients (74 AQP4-IgG and 80 MOG-IgG) were included. Among patients with AQP4-IgG-ON, 20% had chiasmal involvement, compared with 16% of patients with MOG-IgG-ON ( = 0.66). In patients with chiasmal involvement, longitudinally extensive optic nerve enhancement (from orbit extending to chiasm) was identified in 54% of MOG-IgG-ON patients, compared with 7% of AQP4-IgG-ON patients ( = 0.01).
CONCLUSION
Chiasmal involvement of MOG-IgG-ON and AQP4-IgG-ON occur at more similar frequencies than previously reported. Furthermore, MOG-IgG-ON chiasmal involvement is more likely to be part of a longitudinally extensive optic nerve lesion.
Topics: Aquaporin 4; Autoantibodies; Humans; Myelin-Oligodendrocyte Glycoprotein; Neuromyelitis Optica; Optic Chiasm; Optic Neuritis; Retrospective Studies
PubMed: 33975499
DOI: 10.1177/13524585211011450 -
Operative Neurosurgery (Hagerstown, Md.) May 2021Microsurgical resection of craniopharyngiomas poses significant challenges, which are amplified with tumors in the retrochiasmatic location and larger size. Traditional...
Microsurgical resection of craniopharyngiomas poses significant challenges, which are amplified with tumors in the retrochiasmatic location and larger size. Traditional pterional trans-sylvian, subfrontal translamia terminalis, or interhemispheric approaches provide narrow surgical corridors with obstructed visualization of the tumor by the prefixed chiasm and slit optic carotid window.1-5 The superior extension of the tumor compressing the hypothalamus and third ventricle are likewise inaccessible. Dissection through these approaches requires crossing and manipulation of the already compromised optic apparatus with surgical instruments. Finally, the basilar artery and its perforating branches are often adherent to the posterior aspect of the tumor, and are invisible. Endonasal endoscopic techniques have been utilized as a surgical approach that accesses the tumor without crossing the optic apparatus; however, these approaches have a significant risk of cerebrospinal fluid leakage and require dissection of the basilar artery and hypothalamus from long distances with lengthy instruments.6-9 Frequently, the surgeon achieves only partial removal. The petrosal approach is ideal for tumors in the retrochiasmatic location.10-13 Advantages include unhindered access to the retrochiasmatic space without crossing the optic nerve and chiasm. The angle of approach allows visualization superiorly to the hypothalamus. Additionally, the approach shortens the distance to the tumor, allowing for delicate bimanual dissection of the tumor, especially at the basilar artery and hypothalamic interfaces. This video demonstrates three cases of retrochiasmatic craniopharyngioma resection through the petrosal approach, highlighting these advantages to optimize patient outcome. The patients and guardians consented for the surgery, photography, and publication of the patient's image. Figures from Al-Mefty et al11 used with permission from the Journal of Neurosurgery Publishing Group. Additional figures republished from Al-Mefty et al.12 "The petrosal approach for the resection of retrochiasmatic craniopharyngiomas," Neurosurgery, 2008, volume 62, issue 5 Suppl 2 (ONS), ONS331-ONS336, by permission of the Congress of Neurological Surgeons.
Topics: Craniopharyngioma; Humans; Neurosurgical Procedures; Optic Chiasm; Pituitary Neoplasms; Third Ventricle
PubMed: 33940607
DOI: 10.1093/ons/opab045 -
Pituitary Feb 2021To evaluate whether the occurrence of chiasmal herniation coincides with visual field (VF) deterioration and to compare the course of VF defects in patients with and...
PURPOSE
To evaluate whether the occurrence of chiasmal herniation coincides with visual field (VF) deterioration and to compare the course of VF defects in patients with and without radiological chiasmal herniation following treatment of pituitary adenoma.
METHODS
This retrospective cohort study included 48 pituitary macroadenoma patients with chiasm compression, divided into three groups: Group 1 (N = 12), downward displaced optic chiasm and deteriorated VFs; Group 2 (N = 16), downward displaced optic chiasm; Group 3 (N = 20), control-group matched for tumour size and follow-up VFs, in mean deviation (dB). VFs were compared over time and a severity index, Chiasm Herniation Scale (CHS), for herniation based on radiological parameters was designed.
RESULTS
After treatment, all groups showed improvement of VFs (Gr1: 2.97 dB p = 0.097, Gr2: 4.52 dB p = 0.001 and Gr3: 5.16 dB p = 0.000), followed by long-term gradual deterioration. The course of VFs between patients with and without herniation was not significantly different (p = 0.143), neither was there a difference in the course before and after herniation (p = 0.297). The median time till onset of herniation was 40 months (IQR 6 month-10 years) and did not significantly differ (p = 0.172) between the groups. There was no relation between VFs and the degree of herniation (p = 0.729).
CONCLUSION
Herniation does not appear to have clinical relevance with respect to VF outcome. The newly designed CHS is the first scoring system to quantify the severity of herniation and, in the absence of alternatives, may be useful to describe MRI findings to serve future added value in larger sized outcome studies.
Topics: Adult; Female; Humans; Male; Middle Aged; Optic Chiasm; Pituitary Neoplasms; Retrospective Studies; Visual Fields
PubMed: 33057947
DOI: 10.1007/s11102-020-01088-2 -
American Journal of Neurodegenerative... 2015Neurosurgical evidences show that the aging process is initiated between 25 to 30 years of age, in the arcuate nucleus of the hypothalamus. Likewise, experimental and... (Review)
Review
Neurosurgical evidences show that the aging process is initiated between 25 to 30 years of age, in the arcuate nucleus of the hypothalamus. Likewise, experimental and neurosurgical findings indicate that the progressive ischemia in the arcuate nucleus and adjacent nuclei are responsibles at the onset of obesity and, type 2 diabetes mellitus in adults, and essential arterial hypertension (EAH). On the contrary, an omental transplantation on the optic chiasma, carotid bifurcation and anterior perforated space can provoke rejuvenation, gradual loss of body weight, decrease or normalization of hyperglycemia and normalization of EAH; all of them, due to revascularization of the hypothalamic nuclei. Besides, our surgical method have best advantages than the bariatric surgery, against obesity and type 2 diabetes mellitus.
PubMed: 26389015
DOI: No ID Found -
Journal of Comparative Pathology Feb 2023We describe gross and histopathological features of multiple ocular and neuro-ophthalmic abnormalities in a fox squirrel (Sciurus niger). Ophthalmic findings included...
We describe gross and histopathological features of multiple ocular and neuro-ophthalmic abnormalities in a fox squirrel (Sciurus niger). Ophthalmic findings included severe bilateral microphthalmos, with the right eye more affected than the left. Histopathology confirmed severe microphthalmia, aphakia, disorganized retinal tissue and small optic nerves, as well as agenesis of the optic chiasm and optic tract. This combination of neuro-ophthalmic abnormalities has not been previously described in wild animals.
Topics: Animals; Microphthalmos; Optic Chiasm; Sciuridae; Retina; Aphakia; Rodent Diseases
PubMed: 36791601
DOI: 10.1016/j.jcpa.2023.01.001 -
Ophthalmology Dec 2018To describe the phenotypic spectrum of a large cohort of albino patients, to investigate the relationship between the ocular abnormalities and the visual acuity (VA),...
PURPOSE
To describe the phenotypic spectrum of a large cohort of albino patients, to investigate the relationship between the ocular abnormalities and the visual acuity (VA), and to define diagnostic criteria for the white population. We also estimated the prevalence of albinism in The Netherlands.
DESIGN
Retrospective cohort study.
PARTICIPANTS
We investigated the phenotype of 522 patients with albinism from the databases of Bartiméus (452 patients), Leiden University Medical Center (44 patients), and the Academic Medical Center Amsterdam (26 patients).
METHODS
We collected clinical, genetic, and electrophysiologic data of patients with albinism. We used grading schemes for iris translucency, fundus hypopigmentation, and foveal hypoplasia.
MAIN OUTCOME MEASURES
Visual acuity, nystagmus, iris translucency, fundus pigmentation, foveal hypoplasia, and misrouting.
RESULTS
Nystagmus was absent in 7.7% (40/521), iris translucency could not be detected in 8.9% (44/492), 3.8% (19/496) had completely normal fundus pigmentation, 0.7% (3/455) had no foveal hypoplasia, and misrouting was not established in 16.1% (49/304). The VA varied from -0.1 to 1.3 logarithm of the minimum of angle of resolution (logMAR). The foveal hypoplasia grading correlated best with the VA (r = 0.69, P < 0.001), whereas iris translucency, fundus pigmentation, and misrouting did not predict the VA significantly. We estimated a prevalence of albinism in The Netherlands of at least 1:12 000.
CONCLUSIONS
None of the characteristics of albinism were consistently present in our cohort. To be able to distinguish albinism from other conditions with similar ocular features, especially in northern and western European countries, we propose major and minor clinical criteria. Major criteria would be (1) foveal hypoplasia grade 2 or more, (2) misrouting, and (3) ocular hypopigmentation, either iris translucency or fundus hypopigmentation grade 2 or more. Minor criteria would be (1) nystagmus, (2) hypopigmentation of skin and hair, (3) grade 1 fundus hypopigmentation, and (4) foveal hypoplasia grade 1. We propose that 3 major criteria or 2 major and 2 minor criteria are necessary for the diagnosis. In the presence of a molecular diagnosis, 1 major criterion or 2 minor criteria will be sufficient.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Albinism, Oculocutaneous; Child; Child, Preschool; Evoked Potentials, Visual; Female; Fovea Centralis; Humans; Iris Diseases; Male; Middle Aged; Nystagmus, Pathologic; Optic Chiasm; Optic Nerve Diseases; Phenotype; Retrospective Studies; Vision Disorders; Visual Acuity
PubMed: 30098354
DOI: 10.1016/j.ophtha.2018.08.003 -
Bratislavske Lekarske Listy 2022Multiple sclerosis (MS) is an inflammatory demyelinating disease leading not only to physical disability but also to cognitive dysfunction. The aim of our study was to...
Information-processing speed in mildly disabled relapsing-remitting multiple sclerosis patients correlates with volumetry of optic chiasma and subcortical grey matter nuclei.
INTRODUCTION
Multiple sclerosis (MS) is an inflammatory demyelinating disease leading not only to physical disability but also to cognitive dysfunction. The aim of our study was to test cognitive functions of MS patients with mild relapsing-remitting form and to find out the relationship between cognitive functions and brain volumetry.
METHODS
52 patients (RRMSp) and 23 age-related healthy participants (CON) were enrolled. Mild disability was defined by mean EDSS 2.4 (≤ 4.0), and by median of disease duration 5.2 years. Cognitive status was tested using Single Digit Modality Test (SDMT). Brain volumetry was processed in FreeSurfer 2.0.0.
RESULTS
RRMSp patients showed significantly lower SDMT score than CON. SDMT results correlated positively with volume of thalamus, putamen and nc. caudate, and negatively with optic chiasma volume. Compared with CON, RRMSp presented with significantly lower volume in left and right nc. accumbent, cuneus and insular GM, right putamen, total brain cortical grey matter (GM), white matters hypointensities, and 3rd ventricular widths.
CONCLUSION
To our best knowledge, this is the first study that presents results showing a correlation of lower SDMT with higher optic chiasma volume, due to its subclinical chronic demyelination. We confirmed that GM atrophy is involved in cognitive functions in MS (Tab. 3, Fig. 2, Ref. 73).
Topics: Brain; Case-Control Studies; Cognition; Gray Matter; Humans; Magnetic Resonance Imaging; Multiple Sclerosis; Multiple Sclerosis, Relapsing-Remitting; Optic Chiasm
PubMed: 36039887
DOI: 10.4149/BLL_2022_108 -
Child's Nervous System : ChNS :... Nov 2022Optic pathway gliomas (OPGs) constitute approximately 3-5% of childhood intracranial tumors. In this study, the authors presented their experience of using the... (Review)
Review
Endoscopic transnasal surgery in optic pathway gliomas located in the chiasma-hypothalamic region: case series of ten patients in a single-center experience and endoscopic literature review.
OBJECTIVE
Optic pathway gliomas (OPGs) constitute approximately 3-5% of childhood intracranial tumors. In this study, the authors presented their experience of using the endoscopic endonasal approach to treat patients with OPG located in the chiasma-hypothalamic region and aimed to use the infrachiasmatic corridor in the endoscopic endonasal approach as an alternative to the transcranial approach in the surgical necessity of OPGs.
METHODS
We retrospectively analyzed the data of ten patients diagnosed with OPG histopathologically among 3757 cases who underwent endoscopic endonasal surgery between August 1997 and March 2021 at Kocaeli University Faculty of Medicine Pituitary Research Center and Department of Neurosurgery. Mean follow-up period 48.5 months. During the postoperative follow-up period, 3 of these 10 patients underwent reoperation due to tumor recurrence. Combined (endoscopic endonasal approach + transcranial approach) approach was applied to 2 patients in the same session. Surgical and clinical outcomes were evaluated in detail.
RESULTS
Ten patients with a mean patient age of 20.6 ± 11.4 were included in this study. The most common complaint was visual impairment. After surgery, improvement in visual impairment was observed in five patients. No increase in postoperative visual impairment was observed in any of the patients. Postoperative panhypopituitarism was not observed in any of the patients. STR resection was performed in 5 patients and NTR resection in 5 patients. No additional treatment was required during follow-up in 4 of 5 patients who underwent NTR. A total of 6 patients received postoperative radiotherapy treatment.
CONCLUSIONS
In gliomas located in the chiasma-hypothalamic region, appropriate patient selection and endoscopic endonasal surgical treatment may contribute to the elimination of symptoms due to the mass effect of the tumor. It may also contribute to keeping the disease under control with targeted adjuvant therapies by clarifying the pathological diagnosis of the lesion.
Topics: Humans; Retrospective Studies; Neoplasm Recurrence, Local; Endoscopy; Optic Nerve Glioma; Vision Disorders; Treatment Outcome; Pituitary Neoplasms; Neuroendoscopy
PubMed: 36087131
DOI: 10.1007/s00381-022-05665-7 -
Journal of Neuro-ophthalmology : the... Dec 2018The aim of this study was to characterize brain and orbital MRI features of patients with Leber hereditary optic neuropathy (LHON), with particular attention to the...
BACKGROUND
The aim of this study was to characterize brain and orbital MRI features of patients with Leber hereditary optic neuropathy (LHON), with particular attention to the optic nerves and chiasm.
METHOD
We studied a patient cohort with genetically confirmed LHON followed at 2 ophthalmologic hospitals in France between 2013 and 2015. High-resolution brain and orbital MRI studies were analyzed for each patient during the first 12 months after the onset of visual loss was analyzed.
RESULTS
Our study included 20 men and 8 women with a mean age of 38.3 years at diagnosis, and all had genetic mutations for LHON. Nineteen patients (67.9%) had T2 hyperintensity in the posterior portion of both optic nerves and in the optic chiasm, and enlargement of the chiasm was found in 16 patients (59.3%). No enhancement of the optic nerves or chiasm was detected. The T2 hyperintensity lesions were not associated with the time between symptom onset and obtaining MRI, the mutation type, or sex of the patient. Nonspecific T2 white matter lesions were found in MRI of 6 patients, but without the characteristics of those found in patients with multiple sclerosis.
CONCLUSIONS
Involvement of the posterior portions of the optic nerves has been described previously in case reports of patients with LHON. Our results support this observation with neuroimaging performed within 1 year of onset of visual loss. Enlargement of the optic chiasm also may occur in patients with LHON. The pathophysiology of the MRI changes is not yet understood.
Topics: Adult; Female; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Optic Atrophy, Hereditary, Leber; Optic Chiasm; Optic Nerve; Reproducibility of Results; Retrospective Studies
PubMed: 29300239
DOI: 10.1097/WNO.0000000000000621