1/118. Compression of the visual pathway by anterior cerebral artery aneurysm.Visual failure is an uncommon presenting symptom of an intracranial aneurysm. It is even more uncommon in aneurysms arising from the anterior cerebral artery (ACA). We presented 2 patients with an aneurysm of the A1 segment of the anterior cerebral artery causing visual field defects. One patient presented with a complete homonymous hemianopia due to compression of the optic tract by a giant aneurysm of the proximal left A1 segment. The second patient had an almost complete unilateral anopia caused by compression of the optic nerve and chiasm by an aneurysm of the distal part of the A1 segment with a small chiasmatic hemorrhage and ventricular rupture.- - - - - - - - - - ranking = 1keywords = compression (Clic here for more details about this article) |
2/118. Ultrasonographically guided injection of corticosteroids for the treatment of retroseptal capillary hemangiomas in infants.PURPOSE: Injection of corticosteroids is a well-documented and successful mode of treatment for periorbital capillary hemangiomas. Because of the greater potential risk involved with retrobulbar injections, no prior study has described this treatment for tumors located behind the orbital septum. Although retroseptal intraorbital capillary hemangiomas comprise only 7% of all adnexal capillary hemangiomas, complications such as optic nerve compression or astigmatism may necessitate treatment. methods: Three patients with deep orbital hemangiomas that caused vision-threatening complications were treated with intralesional injections of triamcinolone and betamethasone. Orbital injection was performed with use of real-time ultrasonographic guidance of the needle. This technique was valuable in providing continuous, accurate, and safe advancement of the needletip in the orbit to avoid the globe and orbital walls. ultrasonography also permitted precise placement of the needle tip within the tumor and visualization of the injected material. RESULTS: Significant improvement was demonstrated in all cases on the basis of both ultrasonographic measurements and regression of clinical manifestations such as astigmatism, chemosis, proptosis, and optic nerve pallor. No complications were noted. CONCLUSION: Intralesional injection of corticosteroids to treat retroseptal and retrobulbar capillary hemangiomas was found to be a safe and effective treatment modality in our patients. Positioning of the injecting needle was guided by ultrasonography.- - - - - - - - - - ranking = 0.5keywords = compression (Clic here for more details about this article) |
3/118. Results of transmedial-canthal ethmoidal decompression for severe dysthyroid optic neuropathy.PURPOSE: To study the effects of ethmoidal wall (one-wall) decompression using a transmedial-canthal approach (transmedial-canthal ethmoidectomy) for the treatment of dysthyroid optic neuropathy. methods: The ethmoidal wall and air cells were completely removed using a transmedial-canthal approach in 6 eyes of 4 patients (mean age = 55 years; age range, 46-69 years) with dysthyroid optic neuropathy. Similar surgery was performed on 2 contralateral eyes in 2 of the patients for cosmetic reasons. The preoperative corrected visual acuity in the 6 eyes ranged from hand motion to 20/100. Centrocecal scotomas were detected using automatic static threshold perimetry in the 6 eyes. RESULTS: After transmedial-canthal ethmoidectomy, the corrected visual acuity improved to better than 20/20 in the 6 eyes, and the centrocecal scotomas had almost completely resolved. There were no major complications, such as cerebrospinal fluid leakage or diplopia associated with the surgery. There were no relapses during an average follow-up period of 29 months. CONCLUSIONS: These findings suggest that transmedial-canthal ethmoidectomy is an effective and safe therapy for dysthyroid optic neuropathy.- - - - - - - - - - ranking = 2.5keywords = compression (Clic here for more details about this article) |
4/118. Visual recovery after a year of craniopharyngioma-related amaurosis: report of a nine-year-old child and a review of pathophysiologic mechanisms.BACKGROUND: The probability of visual recovery in tumor-related optic neuropathy usually correlates with the severity and duration of optic pathway compromise. Recovery of visual acuity to normal levels is unexpected after profound loss of vision extending for a period of weeks and months. methods: A 9-year-old girl who had neurosurgical resection of a craniopharyngioma compressing the optic chiasm and optic tract was followed up serially with neuroimaging and clinical examinations over a 6-year period. RESULTS: Within 3 months of the diagnosis of craniopharyngioma, the girl's vision was reduced to no-light-perception blindness when she viewed with the more involved eye. The blindness correlated with an amaurotic (i.e., >3.6 log unit) relative afferent pupillary defect and an absence of any response when tested with visual field perimetry. After more than a year of total blindness and cessation of all neurosurgical and radiation therapy, visual acuity recovered to a normal level (20/25), the afferent pupillary defect improved, and sensitivity in a portion of the temporal hemivisual field was restored. In the follow-up that has extended for 5 years from the time of recovery, stability of the restored vision has been documented. CONCLUSION: Children who have tumor-related loss of vision due to damage to the anterior visual pathways may be capable of recovery after intervals of blindness that would be considered irreversible in adults. The mechanism of the recovery in our patient may have been decompression-related restoration of axoplasmic flow, followed by gradual remyelination of visual fibers, which allowed reorganization of connections to the lateral geniculate nucleus to optimize synaptic transmission.- - - - - - - - - - ranking = 0.5keywords = compression (Clic here for more details about this article) |
5/118. Visual loss associated with fibrous dysplasia of the anterior skull base. Case report and review of the literature.The authors present a case of visual loss associated with fibrous dysplasia of the anterior skull base and the surgical management of this case. Preoperative computerized tomography scanning in this patient demonstrated a patent optic foramen and a rapidly growing cystic mass within the orbit, which was responsible for the patient's visual loss. A literature review revealed that this case is typical, in that cystic mass lesions of various types are frequently responsible for visual loss associated with fibrous dysplasia. The authors did not find significant evidence in the literature to support the notion that visual loss associated with fibrous dysplasia is the result of progressive optic canal stenosis, thus raising questions about the value of prophylactic optic canal decompression. Instead, as demonstrated by this case and those uncovered in the literature review, most instances of visual loss result from the rapid growth of mass lesions of cystic fibrous dysplasia, mucoceles, or hemorrhage. Findings of the literature review and the present case of fibrous dysplasia of the anterior skull base support a role for extensive surgical resection in these cases and indicate a need for additional prospective analysis of a larger number of patients with this disease.- - - - - - - - - - ranking = 0.5keywords = compression (Clic here for more details about this article) |
6/118. Idiopathic sclerotic inflammation of the orbit with left optic nerve compression in a patient with multifocal fibrosclerosis.We present the MR imaging findings in a 43-year-old male patient with bilateral idiopathic sclerosing inflammation of the orbit. Bilateral enhancing retrobulbar masses, with concentric compression of the retrobulbar segment of the left optic nerve, were seen. MR imaging proved to be the only means to distinguish between the different intraorbital structures and to determine the exact site of optic nerve compression. To our knowledge, this is the first documented case of MR imaging findings of this entity.- - - - - - - - - - ranking = 3keywords = compression (Clic here for more details about this article) |
7/118. Infantile cerebral aneurysms with visual pathway compression.Intracranial aneurysms are rare in infancy. The commonest presentation is intracranial hemorrhage, but signs of mass effect are more frequent than in adults. We report 2 infants with cerebral aneurysms, one presenting with macrocephaly and another with strabismus. Both had visual loss and optic disc pallor; MRI revealed a suprasellar mass and anterior visual pathway compression. In both cases, the preoperative diagnosis was craniopharyngioma. It is essential to recognize that, although exceedingly uncommon, cerebral aneurysms do occur in infants and have features that differ from those in adults.- - - - - - - - - - ranking = 2.5keywords = compression (Clic here for more details about this article) |
8/118. Reversal of dysthyroid optic neuropathy following orbital fat decompression.AIMS: To document the successful treatment of five patients with dysthyroid optic neuropathy by orbital fat decompression instead of orbital bone decompression after failed medical therapy. methods: Eight orbits of five patients with dysthyroid optic neuropathy were selected for orbital fat decompression as an alternative to bone removal decompression. Treatment with systemic corticosteroids and/or orbital radiotherapy was either unsuccessful or contraindicated in each case. All patients satisfied clinical indications for orbital bone decompression to reverse the optic neuropathy. High resolution computerised tomographic (CT) scans were performed in all cases and in each case showed signs of enlargement of the orbital fat compartment. As an alternative to bone decompression, orbital fat decompression was performed on all eight orbits. RESULTS: Orbital fat decompression was performed on five patients (eight orbits) with optic neuropathy. Optic neuropathy was reversed in all cases. There were no cases of postoperative diplopia, enophthalmos, globe ptosis, or anaesthesia. All patients were followed for a minimum of 1 year. CONCLUSIONS: In a subset of patients with an enlarged orbital fat compartment and in whom extraocular muscle enlargement is not the solitary cause of optic neuropathy, fat decompression is a surgical alternative to bony decompression.- - - - - - - - - - ranking = 7keywords = compression (Clic here for more details about this article) |
9/118. Craniofacial fibrous dysplasia complicated by acute, reversible visual loss: report of two cases.We report two cases of craniofacial fibrous dysplasia which presented with acute visual loss. The first patient had a sphenoid sinus mucocele compressing the optic chiasm. In the second patient the optic canal was narrowed by dysplastic bone. In both cases optic nerve decompression restored vision to normal.- - - - - - - - - - ranking = 0.5keywords = compression (Clic here for more details about this article) |
10/118. Measurement of venous outflow pressure in the central retinal vein to evaluate intraorbital pressure in Graves' ophthalmopathy: a preliminary report.PURPOSE. To evaluate the intraorbital pressure in patients with Graves' ophthalmopathy (GO) in relation to the intraocular pressure (IOP) and proptosis and to find out whether optic nerve compression is predictable. methods. The venous outflow pressure (VOP) in the central retinal vein was measured by the perviously described technique of oculodynamometry.1 Since the central retinal vein passes through the orbit, the VOP cannot be lower than the intraorbital pressure if outflow is to be guaranteed. The IOP was measured either in primary position or with slight chin elevation to avoid restriction of the globe. Fifty-seven patients underwent a complete ophthalmologic examination, including VOP measurements, Hertel exophthalmometry and visual fields. RESULTS. The IOP in primary position ranged between 10 and 29 mmHg and in most (n=54) cases the VOP was 0-4 mmHg higher than the IOP. These patients had neither scotomas nor visual deterioration during an observation period of up to 2 years. In those cases (n=3) where the difference between IOP and VOP was 35 mmHg, the patients developed scotomas and visual deterioration and had to be treated (high-dose steroids or orbital decompression). The elevation in VOP did not correlate with the degree of proptosis. In one unilateral case, treatment of high IOP (32 mmHg) with dorzolamide drops led to a decrease in visual acuity of two lines, inferior field depression and relative afferent pupillary defect. The difference between IOP and VOP was 10 mmHg. Stopping treatment normalized visual function, the IOP rose to its original level and the difference between IOP and VOP was 4 mmHg. CONCLUSION. The increased IOP in GO is not caused by primary glaucoma but by elevated intraorbital pressure. The difference between IOP and VOP must be <5 mmHg to guarantee normal perfusion. We interpret these findings to suggest that loss of visual acuity and visual field defects may not only be caused by optic nerve compression at the apex but also by deterioration of optic nerve head perfusion.- - - - - - - - - - ranking = 1.5keywords = compression (Clic here for more details about this article) |
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