Marked Visual Loss Research Articles

Bone marrow transplantation corrects osteopetrosis in the carbonic anhydrase II deficiency syndrome

Carbonic anhydrase II (CAII), found in renal tubules, brain, and osteoclasts, is critical in acid-base homeostasis and bone remodeling. Deficiency of CAII gives rise to a syndrome of osteopetrosis, renal tubular acidosis (RTA), and cerebral calcification with associated developmental delay. It is inherited in an autosomal recessive fashion and found most frequently in the Mediterranean region and the Middle East. We report 2 related Irish families with clinically severe CAII deficiency in whom the gene mutation has been fully elucidated. Two children, one from each family, have undergone allogeneic bone marrow transplantation because of severe progressive visual and hearing loss. The older 2 children had already developed cerebral calcification and marked visual loss at the time of diagnosis and were treated symptomatically. Post-transplantation evaluation at 2 and 3 years demonstrates histologic and radiologic resolution of their osteopetrosis with stabilization of hearing and vision. Both children remain developmentally delayed and continue to have RTA, and the older child has now developed cerebral calcification. Allogeneic bone marrow stem cell replacement cures the osteoclast component of CAII deficiency and retards the development of cerebral calcification, but it appears to have little or no effect on the renal lesions.

Optic Cup Deepening Spatially Correlated with Optic Nerve Damage in Focal Normal-Pressure Glaucoma

To evaluate whether deepening of the optic cup in patients with focal normal-pressure glaucoma is correlated with the location of most marked loss of neuroretinal rim and visual field. Using morphometric evaluation of color stereo optic disc photographs of 102 eyes of 65 patients with focal normal-pressure glaucoma, the superior half of the optic disc was compared with the inferior half. In eyes in which the optic cup was deepest in the inferior half of the disc, the most pronounced rim loss was located inferiorly significantly more often than superiorly, and the most marked visual field loss was located superiorly significantly more often than inferiorly. In eyes in which the optic cup was deepest in the superior half of the disc, the most pronounced rim loss was located superiorly significantly more often than inferiorly, and the most marked visual field loss was located inferiorly significantly more often than superiorly. Correspondingly, in eyes in which the most marked rim loss was located inferiorly, the deepest optic cup part was located inferiorly significantly more often than superiorly, and vice versa. In focal normal-pressure glaucoma, location of the most marked deepening of the optic cup is spatially correlated with the location of most pronounced neuroretinal rim loss and visual field damage. Because high-pressure glaucoma is typically associated with optic cup deepening and vascular optic nerve damage is associated with optic cup flattening, the spatial correlation between focal optic nerve damage and focal cup deepening may suggest the presence of a pathogenetic aspect in both high-pressure glaucoma and focal normal-pressure glaucoma.

Outcomes of primary phakic trabeculectomies without versus with 0.5- to 1-minute versus 3- to 5-minute mitomycin C

PURPOSE: To compare the intraocular pressure and hypotony outcomes of primary phakic trabeculectomies with no mitomycin C (MMC), shorter MMC, and longer MMC exposure. METHODS: We evaluated primary phakic trabeculectomies with no MMC (36 eyes of 36 patients), 0.5- to 1-minute MMC (50 eyes of 50 patients), and 3- to 5-minute MMC (38 eyes of 38 patients) at the concentration of 0.5 mg/ml. Successful trabeculectomy was defined as an intraocular pressure of 21 mm Hg or less without development of a marked visual acuity loss associated with prolonged hypotony (intraocular pressure < 6 mm Hg over 3 months) and without the need for additional surgery to control intraocular pressure or treat postoperative complications. RESULTS: The three groups were similar in demographics, preoperative intraocular pressure, and medical dependency. However, the incidence of hypotony during the postoperative periods of 3 to 12 months was significantly higher in the 3- to 5-minute MMC group ( P < .05, chi-square test). Severe visual acuity loss associated with hypotony was also more frequently found in the 3- to 5-minute MMC group than in the 0.5- to 1-minute ( P = .009, chi-square test) group or the control group ( P = .014, chi-square test). In addition, the success probabilities were significantly different among the three groups ( P = .001, Kaplan-Meier survival analysis with log-rank test) and were the highest in the 0.5- to 1-minute MMC group and the lowest in the 3- to 5-minute MMC group. CONCLUSION: Shorter application (0.5 to 1 minute) of MMC appears to be optimal for the successful outcome of primary phakic trabeculectomy compared with no MMC or longer application of MMC at a concentration of 0.5 mg/ml.

The clinical presentation of children with tumours affecting the anterior visual pathways

To review the ways in which children with tumours affecting the anterior visual pathways present and to determine the extent of visual loss at presentation and the visual prognosis after treatment. A retrospective review of the 17 children (age 1-13 years at presentation) referred to a specialist paediatric oncology unit. Ten children had extrinsic tumours affecting the chiasmal area whilst 7 had intrinsic gliomas affecting the optic nerve and/or chiasm. Patients were followed up for up to 13 years (median 2 years). The children studied presented with a variety of symptoms including headaches, lethargy and growth failure. Despite the clinical finding of marked visual loss in several cases, visual failure was not prominent amongst the presenting symptoms. After surgical intervention and other treatment vision stabilised or improved; eyes with no perception of light for short periods could regain substantial vision. Children with progressive visual deterioration due to tumours do not readily verbalise their difficulty and may have profound loss at presentation. Standard clinical tests of vision will identify the extent of damage. Visual prognosis depends on the underlying pathology and length of history but prompt treatment may lead to substantial improvement in vision.

Retinal Manifestations of Neurofibromatosis

Five patients presented with vision-threatening retinal tumors and systemic signs of neurofibromatosis, including neurofibromatosis type 1 (four patients) and familial cafe-au-lait spots (one patient). These tumors included large retinal astrocytic hamartomas, multiple retinal capillary hemangiomas, and combined hamartomas of the retina and retinal pigment epithelium, which resulted in rubeotic glaucoma, vitreous hemorrhage, and retinal detachment. Surgical therapy included retinal cryopexy, xenon and argon photocoagulation, scleral buckling, and pars plana vitrectomy with excisional retinal biopsy. Retinal tumors may result in marked visual loss in patients with neurofibromatosis, and vitreoretinal surgery may restore useful vision in some of these patients.

Surgical alternatives in the treatment of cavernous sinus aneurysms.

Direct surgery on aneurysms in the cavernous sinus is a formidable technical procedure. The intimate relationship of the intracavernous carotid artery to the venous structures and to the cranial nerves make surgical access difficult at best. Thirty-two of 356 aneurysm patients presented with symptomatic aneurysms originating from the intracavernous internal carotid artery. Twenty-one patients had aneurysms contained entirely within the cavernous sinus, and in 11 others the aneurysms arose within the cavernous sinus and extended into the subarachnoid space. Of the purely intracavernous aneurysms there were five small aneurysms (less than 25 mm) and 16 giant (greater than or equal to 25 mm) aneurysms. Fifteen patients with purely intracavernous lesions had a superior orbital fissure syndrome, and six had a variety of other symptoms. Of 11 patients with subarachnoid extension, five had a subarachnoid hemorrhage (Grade I or II), five had ipsilateral visual loss, and one had periorbital pain. The aneurysms were treated as follows: Group 1 received progressive ligation of the internal carotid artery in the neck with a Selverstone clamp and a surface superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis (purely intracavernous in nine, and with subarachnoid extension in one); Group 2 underwent trapping of the internal carotid artery and a deep STA-MCA anastomosis (purely intracavernous in seven); and Group 3 had direct clipping of the aneurysm (purely intracavernous in five, and with subarachnoid extension in 10). The cavernous sinus was entered directly through its roof by a pterional craniotomy with radical removal of the optic canal, lesser sphenoid wing, and lateral and superior orbital walls. Proximal control of the internal carotid artery was obtained through a cervical incision. Two patients in Group 1 developed transient neurological deficits, which resolved. Two patients in Group 2 developed a cerebral infarction, one of whom died; in both of these patients, the anastomosis was completed after the internal carotid artery occlusion. Two patients in Group 3 progressed from marked visual loss to blindness of the same side, and one developed an intraventricular hemorrhage during induction of anesthesia and died without surgery. It is proposed that a direct approach to symptomatic aneurysms in the cavernous sinus is the best initial alternative. When this approach is not feasible, a trapping procedure preceded by a high-flow extracranial-intracranial anastomosis may be considered. Although the authors have been able to clip aneurysms of various sizes, this has not been possible in all patients. Further work is needed in this area.

Penetrating Keratoplasty for Pseudophakic Bullous Keratopathy Associated with Semiflexible, Closed-Loop Anterior Chamber Intraocular Lenses

We performed penetrating keratoplasty on 32 eyes that developed pseudophakic bullous keratopathy associated with closed-loop anterior chamber intraocular lenses. All lenses were exchanged at the time of keratoplasty. Seventeen patients received anterior chamber intraocular lenses and 15 patients had a posterior chamber lens sutured to the iris or sclera. Postoperatively, 13 of 32 eyes (41%) achieved a visual acuity of 20/100 or better, and 27 of 32 eyes (84%) had a clear graft. A high incidence of cystoid macular edema (eight cases), and graft rejection (seven cases) resulted in marked visual loss.

Pseudophakic bullous keratopathy.

We reviewed the records of all patients with pseudophakic bullous keratopathy (271 eyes, 251 patients) seen during a six-month period to determine predisposing factors, associated problems, current management, and visual outcome. Pseudophakic bullous keratopathy was associated most frequently with anterior chamber intraocular lenses in general (155 of 271), and with Leiske style lenses in particular (100 of 271). It was associated with a visual acuity of 20/200 or less in 206 eyes and a visual acuity of counting fingers or less in 129 of the eyes at the initial examination. Penetrating keratoplasties had been performed in 189 of the eyes. After penetrating keratoplasty, 108 of 189 of the eyes had a visual acuity of 20/200 or less (mean follow-up, 15 months). Visual acuity improved with longer follow-up, and among patients with a minimum follow-up of two years, 23 of 36 eyes had a visual acuity of 20/100 or better. Most grafts were clear (145 of 189). Pseudophakic bullous keratopathy was associated with marked visual loss, which was permanent despite clear grafts in 29 of 92 eyes followed-up for one year or longer.

Pseudophakic Bullous Keratopathy

We reviewed the records of all patients with pseudophakic bullous keratopathy (271 eyes, 251 patients) seen during a six-month period to determine predisposing factors, associated problems, current management, and visual outcome. Pseudophakic bullous keratopathy was associated most frequently with anterior chamber intraocular lenses in general (155 of 271), and with Leiske style lenses in particular (100 of 271). It was associated with a visual acuity of 20/200 or less in 206 eyes and a visual acuity of counting fingers or less in 129 of the eyes at the initial examination. Penetrating keratoplasties had been performed in 189 of the eyes. After penetrating keratoplasty, 108 of 189 of the eyes had a visual acuity of 20/200 or less (mean follow-up, 15 months). Visual acuity improved with longer follow-up, and among patients with a minimum follow-up of two years, 23 of 36 eyes had a visual acuity of 20/100 or better. Most grafts were clear (145 of 189). Pseudophakic bullous keratopathy was associated with marked visual loss, which was permanent despite clear grafts in 29 of 92 eyes followed-up for one year or longer.

Subperiosteal Orbital Hematoma: Visual Recovery Following Delayed Drainage

Subperiosteal orbital hematomas are rare sequelae of blunt periorbital trauma. Visual loss in such cases is very infrequent, but reportedly irreversible, unless treated with early decompression. A 17-year-old boy developed marked visual loss secondary to an acutely developing traumatic subperiosteal orbital hematoma. Despite delayed referral surgical evacuation of the hematoma remarkably restored his vision. Postoperative clinical examination, fluorescein angiography, and electrophysiologic testing confirmed that a compressive optic neuropathy had caused the visual dysfunction. Although immediate surgical decompression remains the treatment of choice for subperiosteal hematomas producing visual loss, this case demonstrates that the optic nerve may recover dramatically even after a prolonged period of dysfunction from compression.

Blindness From Retrobulbar Injection into the Optic Nerve

We report two patients with marked visual loss due to injection within the optic nerve sheath. Findings included severe visual loss, optic disc edema, retinal edema, and intraretinal, preretinal, and vitreous hemorrhage. A review of similar cases in the literature reveals a common but ill-advised use of sharp retrobulbar needles with the technique of retrobulbar injection described by Atkinson. A modified technique which limits the risk of optic nerve trauma is described.

Acute posterior multifocal placoid pigment epitheliopathy associated with diffuse retinal vasculitis and late haemorrhagic macular detachment.

A 20-year-old healthy man suffered rapid loss of bilateral central vision with placoid lesions at the level of the retinal pigment epithelium and choriocapillaris scattered in the posterior pole of the fundus. In addition, acute vasculitis of the retinal veins was remarkable and widespread throughout the posterior pole and midperiphery. These inflammatory signs subsided in several weeks and were succeeded by recovery of the normal visual acuity with residual pigment derangements in the deep retina. Sixteen months after the onset of the disease choroidal neovascular membranes developed in the macular region of the left eye, followed by haemorrhagic macular detachment and marked visual loss. Significant increases in the serum cold agglutinin titre occurred as isolated laboratory findings concurrently with the acute stage of the disease and the late macular complication, though no clinical or other laboratory sign suggested viral infection.

Contact lens-associated microbial keratitis.

During a 14-year period, 42 cases of microbial keratitis were associated with contact lens (CL) wear. Pseudomonas aeruginosa was isolated in 40% of the cases and Staphylococcus in 31%; Streptococcus pneumoniae, alpha-hemolytic Streptococcus, and Serratia marcescens were the next most commonly isolated pathogens. There was a single fungal corneal ulcer. Bandage CL use was associated with a high prevalence of infection with quasi-commensal organisms and with polymicrobial keratitis, a pattern of disease quite distinct from that induced by other types of CLs. Marked visual loss frequently occurred. There was a disturbing increase in the number of infections associated with extended-wear CLs (worn for either aphakia or myopia) over the last 18 months of the study.

Early Loss of Central Visual Acuity in Glaucoma

Central visual acuity is usually maintained until late in the course of glaucoma. Ten patients (5 men, 5 women) between the ages of 25 and 79 were found to have decreased visual acuity associated with central or centrocaecal scotomas early in their course. Five patients had chronic open-angle glaucoma, three had pigmentary glaucoma, one had juvenile glaucoma, and one had Axenfeld's syndrome. A Marcus Gunn pupil was present in all six patients not on miotics. Most lost central acuity at pressures under 30 mmHg. Seven patients had vision of 20/200 or less. All with marked visual loss had a cup disc rate of .8 or greater. Other causes were carefully ruled out. Proposed mechanisms for the development of these central defects include either double Bjerrum scotomas which extend centrally or early papillomacular bundle involvement due to temporal cupping. This study demonstrates that decreased vision with associated central field loss can be a relatively early finding in glaucoma.

Multifocal and recurrent (serous) choroidopathy (MARC) syndrome: a new variety of idiopathic central serous choroidopathy.

Presented is a group of 110 patients with patches of granular atrophy of the retinal pigment epithelium which I believe represents a new subtype of idiopathic central serous choroidopathy (ICSC). It is designated as multifocal and recurrent (serous) choroidopathy (MARC) syndrome. Such patients are the 'older' ICSC patients and they usually have bilateral involvement which may show marked asymmetry. The history is seldom helpful in defining previous episodes of leaking. The fundus changes are thought to represent the sequelae of multiple, recurrent, or chronic choroidopathy in the form of serous detachments of the retinal pigment epithelium and/or neurosensory retina. Such detachments may not be present at the time of a single examination, and thus the fundus picture may be puzzling without an awareness of this syndrome which exhibits a wide spectrum of severity. Difficulties in detecting the low detachments and fluorescein leaking are emphasized. There is often a marked disparity between the ophthalmoscopic and the fluorescein angiographic pictures, and examination by the latter technique is urged. I do not believe this entity progresses to senile disciform disease, but can result in marked visual loss. If extrafoveal leaking is found in the presence of decreased acuity and a macular detachment, and if there is evidence of previous attacks, photocoagulation can effectively flatten the retina. I believe photocoagulation therapy under these conditions is justifiable.

Risk factors for rate of progression of glaucomatous visual field loss: a computer-based analysis.

Factors affecting the progression of visual field loss were examined in 57 patients with bilateral open angle glaucoma. patients who already had marked visual field loss experienced further field loss at a greatly accelerated rate. Family history of glaucoma, sex, and initial registration intraocular pressure were also important prognostic factors for progressive visual field loss, whereas age and systemic blood pressure were not found to affect rate of visual field loss. Follow-up data from these patients were drawn from a computer-based clinic record system that may serve as a prototype for the collection of information on the natural history of ophthalmic diseases.

Relative Blue-Light Extinction in Lens Nucleus Related to Age and Cataract

The extent of visual function loss from nuclear cataractous change can be estimated by observing the extinction of blue light compared to white light as a function of sagittal lens depth in standard slit lamps. Apparent extinction (loss of transmissivity) of 50% or more of the depth of the lens in blue light of maximal intensity compared to white light at minimal intensity is associated with marked visual loss. However, this transmissivity ratio of 0.5 or less also applies if light intensity remains constant and the blue filter is simply moved in and out of the light beam. Therefore, if 50% or more of the lens appears dark to blue-filtered light, nuclear changes have significantly decreased effective visual acuity. Relative blue-light extinction associated with nuclear change that may be amenable to surgical correction can thus be distinguished from the extinction effect caused by age alone.

Clinical and epidemiological aspects of methylmercury poisoning.

An opportunity to study the effects of methylmercury poisoning in humans was provided by the large outbreak in Iraq in 1971-2. In adults, poisoning resulted from the ingestion of home-made bread prepared from methylmercury-treated seed grain and there was a highly significant correlation between the amount of bread ingested and blood mercury levels. Poisoning in infants resulted either from prior exposure in utero or from suckling or both. Blood mercury levels were higher in infants and children than in adults. There was no increased incidence of congenital defects. Symptoms and signs of poisoning and histopathological changes were mainly confined to the CNS. Symptoms developed, on average, 1-2 months after exposure. In children there was mental retardation with delayed onset of speech and impaired motor, sensory and autonomic function. Severely affected children were blind and deaf. In adults, the clinical picture could be classified as 1, mild (mainly of sensory symptoms) 2, moderate (sensory symptoms accompanied by cerebellar signs) and 3, severe (gross ataxia with marked visual and hearing loss which, in some cases, progressed to akinetic mutism followed by coma). Grades 1 and 2 carried a better prognosis thant grade 3. Interference with transmission at the myoneural junction was found in 14% of patients studied. There was no evidence of peripheral nerve involvement per se and sensory symptoms may be of central origin. The clinical differences between the Iraqi and Japanese outbreaks may be a result, in part at least, of the severe, prolonged and continuous exposure which occurred in the latter outbreak. Improvement was observed among the mild and moderate group. Treatment with chelating agents, thiol resin, haemodialysis and exchange transfusion lowered blood mercury concentrations but produced no convincing clinical benefit. To be effective, treatment may need to be instituted soon after exposure.

Ischemic optic neuropathy.

Ischemic optic neuropathy (ION), based on vascular anatomy of the optic nerve, pathogenesis and clinical picture, consists of two distinct entities: anterior (AION) and posterior (PION) ischemic optic neuropathies. AION is due to interference with posterior ciliary artery supply to the optic nerve head and retrolaminar part of the optic nerve; it initially presents with visual loss and optic disc edema which progresses to optic atrophy in a month or two. PION is due to occlusion of nutrient arteries to the posterior part of the optic nerve; in this condition during the initial stages the optic disc is normal in spite of marked visual loss, but the atrophy develops later on. Their pathogeneses, causes, clinical pictures, diagnosis and management are discussed briefly.

Bilateral Retinal Artery and Choriocapillaris Occlusion Following the Injection of Long-Acting Corticosteroid Suspensions in Combination with Other Drugs: I. Clinical Studies

Two well-documented cases of bilateral retinal artery and choriocapillaris occlusions with blindness following head and neck soft-tissue injection with methylprednisolone acetate in combination with lidocaine, epinephrine, or penicillin are reported. One case had only a unilateral injection. The acute observations included hazy sensorium, superior gaze palsy, pupillary abnormalities, and conjunctival hemorrhages with edema. Follow-up changes showed marked visual loss, constricted visual fields, optic nerve pallor, vascular attenuation, and chorioretinal atrophy. The literature is reviewed, and possible causes are discussed.