Diplopia and variable ptosis as the sole initial findings in a case of orbital plasmacytoma and multiple myeloma.

Plasmacytomas are monoclonal plasma cell tumors. They represent 3% of all orbital tumors. We present an unusual case of orbital plasmacytoma and advanced multiple myeloma where the sole presenting symptoms were those of diplopia and ptosis. Clinical examination revealed right hypertropia and variable left upper lid ptosis but no proptosis. The visual acuity and the rest of the ocular examination were normal in both eyes. An MRI scan of the brain and orbits revealed a frontal bone lesion consistent with a plasmacytoma. A bone marrow biopsy showed a light chain multiple myeloma with free lambda light chains. Although the literature reports diplopia and ptosis as being clinical features of orbital plasmacytomas, to our knowledge this is the first reported case where these symptoms were the only presenting features, despite widespread disease.

Botulinum toxin as a postoperative diplopia test - it can also reduce the angle of deviation prior to surgery.

PURPOSE: To investigate how frequently botulinum toxin, when used as a postoperative diplopia test, reduces the angle of deviation prior to subsequent strabismus surgery. METHODS: A retrospective study of 39 adult patients with constant concomitant horizontal strabismus who had undergone botulinum toxin injections to assess the risk of postoperative diplopia and then subsequently underwent strabismus surgery. RESULTS: Fourteen out of 39 patients (36%) sustained a reduction of 15 prism diopters or more for near and/or distance when comparing the pre-injection angle of deviation with the preoperative angle of deviation. CONCLUSION: Approximately one-third of patients receiving botulinum toxin as a postoperative diplopia test maintained a significant reduction in the angle of their deviation prior to undergoing surgery.

Diplopia following sub-tenon's anaesthesia: an unusual complication.

Diplopia is a rare but well recognised complication following retrobulbar and peribulbar local anaesthesia but it has not been widely reported following sub-tenon's local anaesthesia (STLA). We report on a 76-year-old woman who developed vertical diplopia after left phacoemulsification. She had received a STLA. She had left hypotropia measuring 30 prism diopters for near and distance. She was managed with occlusion but there was no improvement in her findings over 6 months. Ocular motility opinion was then sought and a presumptive diagnosis of inferior rectus fibrosis was made. She subsequently underwent a left inferior rectus recession using adjustable sutures. Postoperatively she had a residual left hypotropia measuring 8 prism dioptres and single vision. Possible causes of inferior rectus fibrosis include muscle damage during traumatic sub-tenon's block or myotoxicity due to local anaesthetic agents. This case highlights the importance of close supervision of inexperienced staff administering regional anaesthetics.

Dorsal midbrain syndrome with loss of motor fusion: a rare association.

INTRODUCTION: Dorsal midbrain syndrome (DMS) is characterized by upgaze paralysis, convergence-retraction nystagmus, and eyelid retraction. Impaired downgaze and pupillary light-near dissociation may co-exist, while less common features including exotropia and convergence paralysis have also been described. However, loss of motor fusion is not a well recognised finding in DMS. PURPOSE: To describe DMS associated with loss of motor fusion. METHODS: Retrospective case series. RESULTS: Five patients (age 21-80 years) presented with features of DMS due to severe head injury (n=1), brainstem stroke (n=3) and pinealoma (n=1). All five complained of constant diplopia with horizontal and vertical separation and had an exotropia (range 20Δ to 70Δ), absent convergence and motor fusion. Two underwent strabismus surgery and subsequently had a variable improvement in their motor fusion. The remaining three patients were managed with occlusion. CONCLUSION: This case series illustrates the complexity of ocular motility findings associated with DMS and highlights the potential difficulties in the management of patients with loss of motor fusion.

Excision of granulation tissue and free conjunctival autograft in the management of necrotizing scleritis.

PURPOSE: To describe a novel use of conjunctival autograft in the management of surgically induced scleral necrosis that occurred after squint surgery. METHODS: Interventional case report. RESULTS: A 22-year-old man underwent bilateral adjustable squint surgery. Two weeks postoperatively, he developed conjunctival retraction and an area of scleral necrosis/melting with 80% thinning. The surrounding conjunctiva was markedly inflamed with raised edges. Screening for autoimmune and vasculitic conditions did not provide any positive results. The conjunctiva surrounding the area of scleral melt was excised and the area covered by a conjunctival autograft resulting in complete healing of the scleral melt within 1 month of surgery. CONCLUSION: The pathogenesis of surgically induced scleral necrosis not associated with autoimmune conditions may be the result of the products of inflammation and lytic enzymes released by the surrounding conjunctival tissue initiating the scleral melting process. This type of surgically induced scleral necrosis may be successfully managed by excision of the surrounding inflamed conjunctiva, thus removing a potential source of collagenases, and covering the exposed sclera by a conjunctival transplant obviating the need for prolonged high-dose immunosuppression.

Chiasmal compression misdiagnosed as normal-tension glaucoma: can we avoid the pitfalls?

Routine neuroimaging for patients with presumed normal-tension glaucoma (NTG) is a contentious issue and it has been suggested that it may be unnecessary due to the low yield for detecting intracranial pathology. However, it has also been reported that 8% of patients diagnosed with NTG have associated compressive lesions of the anterior visual pathways. We present three patients in whom the initial diagnosis of NTG was eventually revealed to be chiasmal compression secondary to a pituitary tumour. Case 1: a 79-year-old woman was treated for NTG for several months before a bitemporal haemianopia developed and imaging showed a pituitary tumour. Case 2: an 83-year-old man was treated for NTG while a magnetic resonance imaging (MRI) scan was requested routinely. This subsequently revealed a pituitary tumour. Case 3: a 52-year-old man with left inferior arcuate visual field loss plus disc pallor was treated for NTG. His visual field deteriorated over 8 years, despite his intraocular pressure (IOP) being well controlled. An MRI was eventually requested, which revealed a pituitary tumour. All of our patients had signs that, with hindsight, should have raised suspicions about the presumptive diagnosis of NTG and initiated neuroimaging at an earlier stage. Whilst compression of the anterior visual pathways is an uncommon finding in patients thought to have NTG, features such as bitemporal field loss, optic disc pallor, poor colour vision and, particularly, poor disc/field correlation should alert the clinician to the possibility of an intracranial mass lesion.

Beware angle kappa: an unusual problem following strabismus surgery.

We report the case of a 33-year-old male with a negative angle kappa which became apparent following surgery for a consecutive exotropia.

Progressive esotropia and restricted extraocular movements associated with low myopia.

We report the case of a 20-year-old female who developed progressive esotropia, which was associated with low myopia and restricted extraocular movements.

Proprioception in extraocular muscles.

Human extraocular muscles are richly endowed with sensory receptors. The precise role of afferent signals derived from these proprioceptors in ocular motor control and spatial localization has been the subject of considerable debate for more than a century. Laboratory-based and clinical studies have increasingly suggested that proprioceptive signals from extraocular muscles influence visuomotor behavior.