Non-arteritic anterior ischemic and glaucomatous optic neuropathy: Implications for neuroretinal rim remodeling with disease severity.

PURPOSE: Post-acute non-arteritic ischemic optic neuropathy (NAION) and glaucomatous optic neuropathy (GON) can be difficult to differentiate clinically. Our objective was to identify optical coherence tomography (OCT) parameters to help differentiate these optic neuropathies. METHODS: We compared 12 eyes of 8 patients with NAION and 12 eyes of 12 patients with GON, matched for age and visual field mean deviation (MD). All patients underwent clinical assessment, automated perimetry (Humphrey Field Analyzer II; Carl Zeiss Meditec, Dublin, CA, USA), and OCT imaging (Spectralis OCT2; Heidelberg Engineering, Heidelberg, Germany) of the optic nerve head and macula. We derived the neuroretinal minimum rim width (MRW), peripapillary retinal nerve fibre layer (RNFL) thickness, central anterior lamina cribrosa depth, and macular retinal thickness. RESULTS: MRW was markedly thicker, both globally and in all sectors, in the NAION group compared to the GON group. There was no significant group difference in RFNL thickness, globally or in any sector, with the exception of the temporal sector that was thinner in the NAION group. The group difference in MRW increased with increasing visual field loss. Other differences observed included lamina cribrosa depth significantly greater in the GON group and significantly thinner central macular retinal layers in the NAION group. The ganglion cell layer was not significantly different between the groups. CONCLUSIONS: The neuroretinal rim is altered in a dissimilar manner in NAION and GON and MRW is a clinically useful index for differentiating these two neuropathies. The fact that the difference in MRW between the two groups increased with disease severity suggests distinct remodelling patterns in response to differing insults with NAION and GON.

The Halifax Explosion of 1917: the oculist experience.

BACKGROUND: Despite its prominence in Canadian history, there are few publications about the Halifax Explosion of 1917 that deal with the care of victims with eye injuries. METHODS: Archived documents relating to the nature and treatment of eye injuries sustained during the Halifax Explosion were reviewed at the Public Archives of Nova Scotia and the Maritime Museum of the Atlantic. A review of current literature was performed. RESULTS: Detailed accounts regarding the personal and surgical experience of 2 ophthalmologists, G.H. Cox and F.T. Tooke, were found. Several unpublished government and personal documents on eye injuries sustained during the Halifax Explosion are filed at the Public Archives of Nova Scotia. Twelve ophthalmologists treated 592 people with eye injuries and performed 249 enucleations. Sixteen people had double enucleations. Most of the eye injuries were caused by shards of shattered glass. Sympathetic ophthalmia was the feared complication for penetrating eye injuries and a common indication for enucleation in 1917. A Blind Relief Fund was established to help treat, rehabilitate, and compensate the visually impaired. INTERPRETATION: Many of the eye injuries sustained during the Halifax Explosion were due to flying shards of glass. Details of their treatment provide insight into a unique and devastating event in Canadian medical history and demonstrate how eye injuries were managed in 1917.

Occipital condyle syndrome as the first sign of metastatic cancer.

BACKGROUND: Occipital condyle syndrome is characterized by severe, unilateral, occipital headache and ipsilateral twelfth-nerve palsy. It is associated with skull-base metastasis. CASES: We identified two patients with sub-acute onset of severe, unilateral, occipital headache and ipsilateral tongue paralysis. The first patient was a 58-year-old woman with a history of limited stage small-cell lung cancer in clinical remission. The second patient was an otherwise healthy 36-year-old man. Neither patient had any other findings on general medical or neurological examination. One patient had only equivocal findings on initial magnetic resonance imaging (MRI), and the other patient's MRI was normal. Although initial work-up for metastatic disease was normal, the first patient developed severe bone pain over the next few months, and follow-up investigations demonstrated metastases to her spine, tibia, skull base and brain. The second patient improved initially, but was admitted to hospital three months later with constitutional symptoms and pancytopenia. Bone marrow and lymph node biopsies were consistent with Stage IVB Hodgkin's lymphoma. CONCLUSION: Occipital condyle syndrome can be the first presentation of disseminated malignancy. Initial imaging of the brain and skull base may be normal, and recognition of this syndrome warrants thorough investigation and close follow-up.

The dilated pupil: an update.

The dilated pupil can present a significant challenge to the clinician. Although in most cases a complete history and physical examination is sufficient to make an accurate diagnosis, selected patients will require further investigation, including pharmacologic testing and neuroimaging. This review outlines the physiology, clinical features, and diagnostic approach to the most important causes of the dilated pupil. Particular attention is given to recent publications on this topic.

The Halifax disaster (1917): eye injuries and their care.

Explosions, man-made and accidental, continue to require improved emergency medical responses. In the 1917 Halifax Explosion, an inordinate number of penetrating eye injuries occurred. A review of their treatment provides insight into a traumatic event with unique ophthalmological importance. Archived personal and government documents relating to the Halifax Explosion were reviewed at the Public Archives of Nova Scotia, Canada, along with a review of current literature. Twelve ophthalmologists treated 592 people with eye injuries and performed 249 enucleations. Sixteen people had both eyes enucleated. Most of the eye injuries were caused by shards of shattered glass. A Blind Relief Fund was established to help treat and rehabilitate the visually impaired. The injured were given pensions through the Canadian National Institute for the Blind, Toronto, Ontario, Canada, which continue to this day. Sympathetic ophthalmia was the feared complication for penetrating eye injuries and a common indication for enucleation in 1917. Even so, the severity and the overwhelming number of eye injuries sustained during the Halifax Explosion made it impossible for lengthy eye-saving procedures to be performed. Enucleation was often the only option.

Neuro-ophthalmology and multiple sclerosis.

PURPOSE: To describe the pertinent neuro-ophthalmic disorders seen in multiple sclerosis (MS). METHODS: Literature pertinent to the discussion of both the afferent and efferent neuro-ophthalmic disorders seen in MS are reviewed. This review is supplemented with illustrative case reports to demonstrate the hallmark issues in regards to demyelinating disease and its effect on the visual system. RESULTS: Numerous disorders of vision can be caused by the central nervous system lesions of MS, but the main findings are optic nerve dysfunction in the afferent visual system and internuclear ophthalmoplegia and nystagmus in the efferent visual system. Magnetic resonance imaging has revolutionized the ability to correlate the patient's presentation with the etiologic CNS lesion and as well has become a cardinal component of the diagnostic criteria of MS. Early diagnosis is now being emphasized as immunomodulatory treatments exist that have altered the natural history of MS. CONCLUSION: It is important to carefully assess the neurovisual system in patients presenting with even minor neurologic complaints. Abnormalities seen on exam could indicate the presence of a subtle organic disorder that triggers investigatory studies that may reveal CNS demyelination (MS). Early diagnosis and treatment of MS are being emphasized for optimal patient care.

Visual disturbances and migraine.

There is a close relationship between headache and the visual system. Visual symptoms are prominent features of clinical syndromes such as migraine, cluster headache, and the trigeminal autonomic cephalgias. There are also strong links between headache and the visual system on the basis of genetics, molecular biology, neurophysiology, and neuroimaging. Studies of these links are leading to the development of novel therapies for a variety of headache syndromes. This review is designed to summarize the most recent literature on headache and the visual system. A particular emphasis is placed on publications of interest to clinicians.

Unilateral hypoplasia of the trigeminal ganglion.

CASE REPORT: We report a case of unilateral anaesthesia of the V1 (ophthalmic) division of the trigeminal cranial nerve presenting with persistent corneal erosions and ulceration secondary to trigeminal ganglion hypoplasia. The patient had a lifelong history of unexplained left-sided ophthalmic symptoms for which numerous diagnoses were provided. Cranial nerve testing demonstrated partial trigeminal dysfunction on the left side. Further investigation eliminated viral etiologies, and subsequent magnetic resonance imaging determined that the patient had a hypo-plastic left trigeminal ganglion. COMMENTS: We present the case to alert clinicians to the possibility of this rare condition.