Nagham Al-Zubidi

Optic nerve sheath fenestration vs cerebrospinal diversion procedures: what is the preferred surgical procedure for the treatment of idiopathic intracranial hypertension failing maximum medical therapy?

Although most patients with idiopathic intracranial hypertension (IIH) can be effectively treated with conservative measures, such as lumbar puncture, weight loss, acetazolamide, medical treatment of headaches, surgery is sometimes necessary, particularly in patients with visual loss secondary to chronic papilledema (1–4). Recently, endovascular venous stenting of a stenosed dominant intracranial transverse venous sinus has been proposed as a possible treatment (5); however, cerebrospinal fluid (CSF) shunting and optic nerve sheath fenestration (ONSF) remain among the most commonly used surgical procedures to treat IIH in the United States (6). In the absence of any prospective, randomized clinical trials comparing these procedures for the treatment of IIH, opinions vary greatly between ONSF and CSF shunting procedures as the most appropriate recommended surgical treatment (7,8). The decision to use one or the other is often based on local preferences and the availability of specific surgeons; some centers always perform ONSF as a first-line treatment, some use both procedures based on patient’s symptoms and signs (ONSF for visual loss and shunts for headaches), while others exclusively recommend lumboperitoneal shunt (LPS) or ventriculoperitoneal shunt (VPS) when surgery is necessary (9).

An Update on Eye Pain for the Neurologist

Pain in and around the eye with or without an associated headache is a common presenting complaint to the neurologist. Although the main causes for eye pain are easily diagnosed by simple examination techniques that are readily available to a neurologist, sometimes the etiology is not as obvious and may require a referral to an ophthalmologist. This article summarizes and updates our prior review in Neurologic Clinics on this topic and includes (1) ocular and orbital disorders that produce eye pain with a normal examination, (2) neurologic syndromes with predominantly ophthalmologic presentations, and (3) ophthalmologic presentations of selected headache syndromes.

Diffusion tensor imaging in traumatic optic tract syndrome

W e read with interest, the report by Bodanapally et al (1) of using diffusion tensor imaging (DTI) in evaluating patients with traumatic optic neuropathy (TON). The authors concluded that decreased axial diffusivity and mean diffusivity in the posterior segment of the optic nerve might serve as a biomarker of axonal damage in patients with TON. We describe a patient with right homonymous hemianopia who presented 11 years after a severe closed head trauma with a negative conventional magnetic resonance imaging (MRI) and magnetic resonance angiography in whom left optic tract atrophy was documented with DTI. A 59-year-old woman complained of transient visual loss. In 1999, she was involved in a motor vehicle accident with loss of consciousness and associated memory loss. Recently, she reported 2 episodes of transient “tunneling of vision,” each lasting 5 minutes. She was not certain if they were monocular or binocular. Her evaluation for these episodes was unremarkable, and they spontaneously resolved with no recurrence. On examination, the patient was found to have a right homonymous hemianopia, but she was unaware of this visual field loss. MRI of the brain with and without contrast was unremarkable. Eighteen months later, despite normal intraocular pressures, the patients optic discs were believed to be suspicious for glaucoma, although she was not started on the treatment. Her medical, surgical, social, and family histories were noncontributory, and she was on no medications. Neuro-ophthalmological testing demonstrated visual acuity 20/25 in the right eye and 20/20 in the left eye. The pupils were isocoric with a right relative afferent papillary defect. Slip-lamp examination showed mild nuclear sclerotic cataracts, and intraocular pressures were 20 mm Hg, right eye, and 19 mm Hg, left eye. Funduscopy showed both optic discs to have enlarged cup-to-disc ratio, and the right disc demonstrated band optic atrophy (Fig. 1). Automated perimetry revealed an incongruous right homonymous hemianopia (Fig. 2). The pattern of retinal nerve fiber layer loss on optical coherence tomography of the right eye confirmed FIG. 1. The right optic disc shows band atrophy and horizontal cupping. The left disc has temporal pallor with vertical cupping.

Deformable anatomic templates embed knowledge into patient's brain images: Part 1. construction and display

Objective This paper describes the methods used to create annotated deformable anatomic templates (DATs) and display them in a patient’s axial 2-dimensional and reformatted volume brain images. Methods A senior neuroradiologist annotated and manually segmented 1185 color-coded structures on axial magnetic resonance images of a normal template brain using domain knowledge from multiple medical specialties. Besides the visible structures, detailed pathways for vision, speech, cognition, and movement were charted. This was done by systematically joining visible anatomic anchor points and selecting the best fit based on comparisons with cadaver dissections and the constraints defined on the companion 2-dimensional images. Results The DAT is commercially available for use on a picture archiving and communication system or as a standalone workstation. Conclusions The DAT can quickly embed extensive, clinically useful functional neuroanatomic knowledge into the patient’s brain images. Besides labeling visible structures, DAT displays clinically important, previously uncharted subdivisions of the fiber tracts.

Nonorganic Visual Loss in Children

NOVL in children is a relatively common problem for the comprehensive ophthalmologist. Although the etiology and pathophysiology of NOVL are variable, rare cases are because of physical or sexual abuse. Clinical tests can make the diagnosis of NOVL, and nonorganic is our preferred terminology for NOVL. Clinicians should be careful to establish a normal eye examination and prove that the vision is better than claimed before labeling a patient with NOVL. Rarely, the clinical examination is insufficient to establish the diagnosis of NOVL and electrophysiology may be helpful. Reassurance is generally all that is necessary for most children with NOVL, but some patients might benefit from formal psychiatric evaluation. The possibility of nonorganic overlay should also be considered in children with NOVL, and the combination of organic and NOVL is relatively common.

Conjugal giant cell arteritis.

While the pathogenesis of giant cell arteritis (GCA) remains unclear, a number of factors may be contributory, including genetic, environmental, and immune. There have been few reports of GCA occurring in a conjugal pair, all originating from Northern Europe or the Northern United States. We document GCA occurring in a husband and wife from the southern Gulf Coast of the United States and discuss the implications of this, as well as the current understanding of the pathogenesis of GCA.

Invasive thymoma in ocular myasthenia gravis: diagnostic and prognostic implications.

W e read with great interest the recent article by Bruce and Kupersmith (1) discussing the safety of prednisone in treating patients with ocular myasthenia gravis (OMG). Yet before treatment, there are critically important steps in evaluating these patients. We illustrate this point by presenting 2 cases of OMG that were found to have invasive thymoma. Case 1: A 50-year-old Hispanic man presented with a 4-month history of ptosis and diplopia, which was worse in the evening and better in the morning. He had no other symptoms. Visual acuity was 20/20 bilaterally. External examination showed bilateral variable ptosis, which increased with sustained upgaze, mild orbicularis weakness, and positive Cogan lid twitch sign. The pupils were isocoric, and there was no relative afferent pupillary defect. Ocular motility revealed variable exotropia of 12–16 prism diopters and bilateral pseudointernuclear ophthalmoplegia. Ice test was positive, resulting in an improvement in ocular motility and ptosis. Ophthalmoscopy was normal bilaterally. Serum acetylcholine receptor antibodies were elevated: binding antibody = 33.0 nmol/L (positive, .0.5 nmol/L); blocking antibody = 48% (positive, .25%); modulating antibody = 44% (positive, .26%). Electromyographic and nerve conduction studies were diagnostic of myasthenia gravis. Computed tomography (CT) of the chest revealed a thymic mass (Fig. 1A). At surgery, in addition to thymectomy, pericardial resection was performed because the tumor was found to be invading the pericardium. Pathology confirmed invasive thymoma, with mixed pattern grade B1, B2, and focal B3, and no lymphovascular or perineural invasion (stage III). Following surgery, the patient had near complete resolution of his myasthenic symptoms. Case 2: A 67-year-old Caucasian woman developed leftsided ptosis and diplopia, and edrophonium testing and acetylcholine receptor antibodies were positive. CT of the chest disclosed nodular densities in the anterior mediastinum (Fig. 1B). Thymectomy revealed invasive thymic epithelial neoplasm with conventional and atypical features (stage II, grade B3). The patient received postoperative radiation therapy, and positron emission tomography (PET) and CT performed within the first year and a half the following surgery were negative for tumor recurrence or metastases. Nineteen months after initial presentation, the patient developed an acute exacerbation of myasthenia gravis with ptosis, diplopia, shortness of breath, and upper extremity weakness. She had a complicated hospital course including atrial fibrillation and respiratory failure, and she was discharged 4 months later on weekly plasmapheresis, pyridostigmine, and prednisone. On examination, there was mild bilateral orbicularis weakness, but no Cogan lid twitch sign and variable exotropia of 20–50 prism-diopters and right hypertropia. Follow-up PET and chest CT have remained stable. We emphasize 3 important points from our cases. First, it is essential that we remind our referring clinicians to obtain imaging of the mediastinum in patients with ocular and generalized myasthenia gravis (2,3). Second, delayed diagnosis and treatment of thymoma can lead to disease progression, a higher stage at diagnosis, and a worse systemic outcome as more invasive stages correlate with higher mortality rates (4,5). Third, patients who have undergone thymectomy for malignant or invasive disease and present FIG. 1. A. Case 1. Thymic mass measures 20 · 20 · 23 mm. B. Case 2. Thymoma appears as multiple nodular densities measuring 14 · 10 mm. Circle denotes thymoma.

Neuro-ophthalmologic features of chordoid glioma

Chordoid glioma is a rare intracranial tumor typically arising in the third ventricle, particularly along the anterior aspect of the hypothalamic wall. We describe the clinical, neuroimaging, and pathologic factors of this neoplasm in a patient presenting with a chiasmal syndrome.

Neuro-ophthalmology as a career

This essay was written to discuss the reasoning behind the personal decisions made by 2 current neuro-ophthalmology fellows to pursue neuro-ophthalmology as a career. It is meant to enlighten the reader about what role neuro-ophthalmologists play in clinical practice, what makes neuro-ophthalmology unique to all other sub-specialties, and how this contributes to making neuro-ophthalmology not only one of the most medically interesting, yet rewarding sub-specialties in ophthalmology.

Systemic corticosteroids in nonarteritic ischemic optic neuropathy

Nonarteritic ischemic optic neuropathy (NAION) is one of the most prevalent optic nerve disorders seen in ophthalmic practice. The role of corticosteroid therapy in NAION remains a highly controversial area of debate in ophthalmology. This brief review will provide an overview of the current clinical evidence on this topic as well as some comment on the medical debate.