An unusual parasagittal tumour with acute blindness and response to cerebrospinal fluid shunting

We report a seven-year-old girl who presented with a sudden tumor apoplexy due to a parasagittal hemangiopericytoma. Following tumor excision, the child was noted to have bilateral optic nerve dysfunction and progressive papilledema, despite rapid overall neurological improvement. Based on the clinical features, we feel that this case represents an unusual form of visual deterioration related to impaired CSF absorption somehow precipitated by the acute tumour apoplexy. This unusual case of blindness responded significantly to CSF shunting. Several reports exist describing raised intracranial pressure with papilledema caused by nonthrombotic sinus occlusion due to tumors in proximity to the posterior superior sagittal sinus, torcular herophili and the jugular outlet. Communicating hydrocephalus, pseudotumor syndrome or intracranial venous sinus obstruction should be considered when otherwise inexplicable visual loss coexists with optic nerve dysfunction and papilledema. We emphasize the importance of a thorough search for the cause of visual loss.

Osteo-odonto-keratoprosthesis surgery: a combined ocular–oral procedure for ocular blindness

The aim of this retrospective study was to describe the oral procedures used in osteo-odonto-keratoprosthesis (OOKP) surgery, and the demographics and oral findings of candidate patients in Singapore. The OOKP procedure utilizes an autologous tooth-bone complex to mount a poly-methylmethacrylate optical cylinder, as an artificial cornea, stabilized by an overlying autologous buccal mucosal graft. Consecutive patients referred over 3 years for dental evaluation prior to OOKP surgery were included. A total of 21 patients underwent oral clinical and radiographic evaluation. The aetiology of blindness included Stevens-Johnson's syndrome (11 cases), chemical burns (9 cases) and multiple failed corneal grafts (1 case). Evaluation revealed that 12 patients were suitable for OOKP surgery, 8 were at risk of complication or failure and 1 had no usable teeth. Fourteen patients have undergone unilateral OOKP Stage 1 surgery successfully. Complications included fracture of a tooth from its lingual bone necessitating the harvesting of a second tooth (1 case), oronasal perforation (1 case), exposure of adjacent roots (5 teeth), lower lip paresthesia (2 cases) and submucosal scar band formation in the buccal mucosal graft donor site (10 cases). Thirteen patients have completed Stage 2 surgery, with attainment of their best possible visual potential following OOKP surgery.

Penetrating orbito-cranial and ocular cow-horn injuries

Cow horn eye injuries are not common but are devastating causes of uniocular blindness amongst young active population. Early and appropriate intervention can save the life of the patient depending on the severity of the injury. This uncommon cause of unilateral visual loss can be prevented if slaughtering of cows are done by trained and appropriately equipped personnel.

Vision following extended congenital blindness

Animal studies suggest that early visual deprivation can cause permanent functional blindness. However, few human data on this issue exist. Given enough time for recovery, can a person gain visual skills after several years of congenital blindness? In India, we recently had an unusual opportunity to work with an individual whose case history sheds light on this question. S.R.D. was born blind, and remained so until age 12. She then underwent surgery for the removal of dense congenital cataracts. We evaluated her performance on an extensive battery of visual tasks 20 years after surgery. We found that although S.R.D.'s acuity is compromised, she is proficient on mid- and high-level visual tasks. These results suggest that the human brain retains an impressive capacity for visual learning well into late childhood. They have implications for current conceptions of cortical plasticity and provide an argument for treating congenital blindness even in older children.

Severe Reactive Ischemic Posterior Segment Inflammation in Acanthamoeba Keratitis

OBJECTIVE

To describe a newly recognized clinical syndrome in Acanthamoeba keratitis consisting of severe reactive ischemic posterior segment vascular inflammation.

DESIGN

Noncomparative, retrospective, single-institution observational case series.

PARTICIPANTS

Five eyes of 5 patients with Acanthamoeba keratitis.

METHODS

A retrospective review of the records of patients diagnosed with Acanthamoeba keratitis between January 1, 1995, and December 1, 2005, was conducted to identify those who underwent eventual enucleation. Five enucleated eyes of 118 eyes with Acanthamoeba keratitis were identified.

MAIN OUTCOME MEASURES

History, clinical examination results, available laboratory study results, and histopathologic examination results.

RESULTS

Histopathologic examination showed Acanthamoeba cysts in the cornea in 4 eyes, whereas it failed to demonstrate amebic cysts or trophozoites in the posterior segment of all eyes studied and unexpectedly revealed chronic chorioretinal inflammation with perivascular lymphocytic infiltration and diffuse neuroretinal ischemia in 4 of 5 eyes. Retinal artery thrombosis was present in 3 of the 4 involved eyes, and central retinal artery and vein thrombosis was found in 1 eye. Hematologic studies in 3 patients showed abnormal anticardiolipin antibody levels in 1 patient and factor V Leiden deficiency in another.

CONCLUSIONS

Prolonged Acanthamoeba keratitis can result in a severe sterile ischemic posterior segment inflammation that is potentially blinding, especially in patients with underlying hypercoagulation disorders.

Comparing outcomes of enucleation and evisceration

PURPOSE

To compare clinical outcomes of enucleation and evisceration by functional and aesthetic measures.

DESIGN

Retrospective, nonrandomized, comparative analysis.

PARTICIPANTS

Eighty-four patients who underwent enucleation or evisceration.

METHODS

The medical records of the participants were retrospectively reviewed. Clinical photographs were graded by blinded observers for qualitative measures.

MAIN OUTCOME MEASURES

Postoperative eyelid and motility measurements, as well as subjective grades of various aesthetic and functional outcomes.

RESULTS

There is no statistically significant difference in the overall aesthetic outcome of enucleation and evisceration, although several specific comparisons were found to be significant. Implant motility score is higher in eviscerated eyes (5.58+/-2.08) than in enucleated eyes (4.35+/-1.69) (P = 0.05). Adduction of the implant is significantly less than abduction in eviscerated eyes (1.34 vs. 1.44; P = 0.02). Implant motility is greater than prosthesis motility. Both enucleation and evisceration result in enophthalmos and a sulcus defect. Seven of 32 patients (21.9%) who underwent enucleation experienced a complication, whereas only of 7 of 52 patients (13.5%) who underwent evisceration experienced a complication (P = 0.0002). The 2 most common complications were implant exposure and formation of a pyogenic granuloma.

CONCLUSIONS

Although enucleation and evisceration produce aesthetically similar outcomes, eviscerated eyes have better implant motility and experience fewer complications. Both enucleation and evisceration result in enophthalmos, sulcus contour defects, and incomplete transfer of implant motility to the prosthesis.

Return of vision after transarterial coiling of a carotid cavernous sinus fistula: case report

BACKGROUND

Carotid cavernous sinus fistulae are abnormal communications between the carotid circulation and cavernous sinus that may arise spontaneously or develop after craniocerebral trauma. They may present with a constellation of signs and symptoms characteristic of raised cavernous sinus pressure, including orbital or retro-orbital pain, pulsatile proptosis, chemosis, ocular or cranial bruit, deterioration of visual acuity, or ophthalmoplegia. Visual loss is likely the result of multiple insults to the visual system, including reversal of venous drainage from the fistula, arterial flow into the superior ophthalmic vein, increased intraocular venous pressure, venous stasis retinopathy, and eventually ischemic optic neuropathy [Brodsky MC, Hoyt WF, Halbach VV, et al. Recovery from total monocular blindness after balloon embolization of carotid-cavernous fistula. Am J Ophthalmol 1987;104:86-87; Sanders MD, Hoyt WF. Hypoxic ocular sequelae of carotid-cavernous fistulae: study of the causes of visual failure before and after neurosurgical treatment in a series of 25 cases. Br J Ophthalmol 1969;53:82-97].

CASE DESCRIPTION

With few exceptions, the literature is replete with evidence of persistent blindness despite successful treatment of the CCF [Albuquerque FC, Heinz GW, McDougall CG. Reversal of blindness after transvenous embolization of a carotid-cavernous fistula: case report. Neurosurgery 2003;52:233-237; Brodsky MC, Hoyt WF, Halbach VV, et al. Recovery from total monocular blindness after balloon embolization of carotid-cavernous fistula. Am J Ophthalmol 1987;104:86-87; Weinstein JM, Rufenacht DA, Partington CR, et al. Delayed visual loss due to trauma of the internal carotid artery. Arch Neurol. 1991;48:490-497]. Here, we report a patient who experienced recovery of vision after endovascular obliteration of the offending CCF.

DISCUSSION

To our knowledge, this is the second reported case of recovery of visual function in a patient presenting with loss of light perception after treatment of a direct CCF.

An eye opening technique

Janice Hopkins Tanne talks to James Aquavella, the US surgeon who implanted an artificial cornea into a British baby boy who was born blind in one eye

Optic nerve avulsion from door-handle trauma in children

AIM

To report severe visual loss caused by optic nerve avulsion (ONA) in children with door-handle trauma.

METHODS

Clinical records at a tertiary eye care hospital, of 14 children who sustained severe visual loss as a result of door-handle injuries, were reviewed. The data were analysed for location, presenting symptoms and signs, diagnostic studies, intervention, and the cause of visual loss.

RESULTS

There were 11 males and three females with an average age of 8 years and an average height of 125 cm. The place of trauma was home in 11 and school in three children. Presenting visual acuity (VA) was light perception (LP) in five patients and no light perception (NLP) in nine. All the 14 children had evidence of ONA and four patients had ruptured eye globes that required initial repair. The diagnosis of ONA was made clinically or by imaging studies and confirmed histopathologically in eyes that were enucleated. Average follow up was 28.8 months (range 4 months to 8 years). Final VA was LP in one patient and NLP in 13 patients, eight eyes required enucleation for painful blind eye or to achieve optimal cosmesis.

CONCLUSION

ONA was the common cause of visual loss in children who sustained ocular trauma caused by door-handles.

Carotid endarterectomy for ophthalmic manifestations: is it ever indicated?

Four ophthalmic manifestations make up a substantial proportion of the indications for carotid endarterectomy (CE). They include transient monocular visual loss (TMVL), ocular ischemic syndrome (OIS), retinal artery occlusion (RAO), and asymptomatic Hollenhorst plaque. Critical review of the literature shows that the evidence to support the efficacy of CE in these four settings is tenuous.

The value of corneal transplantation in reducing blindness

PURPOSE

To analyse the role of keratoplasty in reducing world blindness due to corneal diseases.

METHODS

Review of published literature. We collected and analysed articles published in the English language literature related to the prevalence and causes of blindness in different parts of the world, causes of corneal blindness, and outcome of corneal transplantation for various corneal diseases.

RESULTS

A total of 80% of the world's blind live in developing countries. Retinal diseases are the most important causes of blindness (40-54%) in established economy nations while cataract (44-60%) and corneal diseases (8-25%) are the most common causes of blindness in countries with less developed economies. Keratitis during childhood, trauma, and keratitis during adulthood resulting in a vascularized corneal scar and adherent leucoma are the most frequent causes of corneal blindness in developing countries. Corneal diseases are responsible for 20% of childhood blindness. Nearly 80% of all corneal blindness is avoidable. The outcome of keratoplasty for vascularized corneal scar and adherent leucoma is unsatisfactory, necessitating repeat surgery in a high proportion of these cases. Other barriers for keratoplasty in these nations are suboptimal eye banking, lack of trained human resources, and infrastructure.

CONCLUSIONS

Since the developing world carries most of the load of corneal blindness and the major causes of corneal blindness are corneal scar and active keratitis, development of corneal transplantation services need a comprehensive approach encompassing medical standards in eye banking, training of cornea specialists and eye banking personnel and exposure of ophthalmologists to care of corneal transplants for better follow-up care. However, concerted efforts should be made to develop and implement prevention strategies since most corneal blindness is preventable.

A profile of destructive surgery in Nepal Eye Hospital

This is a study profile of the patients undergoing destructive surgery in Nepal Eye Hospital over a period of 2 years (2001-2003). The rationale of the study was to know the incidence and causes for destructive surgery (enucleation/evisceration) and the measures to prevent them. Patients admitted in the ward from emergency and outpatients departments for the purpose of enucleation and evisceration were taken into this study. Their visual acuity, slit-lamp examinations, fundus evaluation were done. Most of the patients had no perception of light with painful blind eyes, panophthalmitis, endophthalmitis, staphylomas, crush injuries and malignancies. After a decision made by the surgeons in the round, a full consent was taken for the operation. Evisceration was done for cases with history of ocular infections and the rest were enucleated. Destructive operation was done for (a) saving the other eye, (b) life saving, (c) painful condition and disfigurement. The incidence of destructive surgery in Nepal Eye Hospital was 1.40%. male : female ratio was 1.41:1. The causes for destructive surgery were panophthalmitis (31.71%), painful blind eye (21.95%), endophthalmitis (14.63%), staphyloma (14.63%), retinoblastoma (12.20%) and crush injuries (4.88%). Number of evisceration (73.17%) was higher than enucleation (26.83%) as most of the cases were sequele of corneal ulcer. Enucleation was mostly seen in children and evisceration in adults. Lastly, the incidences of destructive surgery would be minimized by (a) Prompt treatment of corneal ulcers for reducing panophthalmitis (b) pre, intra, and post operative care in intra ocular surgery for reducing endophthalmitis, and (c) genetic counselling (pre marital) for reducing childhood malignancies. Decision for destructive surgery should be a team work rather than a single surgeon's opinion. It should be done under general anaesthesia or retrobulbar block. Precaution must be taken to prevent the appalling tragedy of enucleating the wrong eye by marking above on the eye to be operated or EUA prior to surgery. Last but not the least, there should be fitting of a prosthesis for cosmesis, psychological support and careful follow-up of the healthy eye.

Severe eye injury in an 11-year-old child during threshing--A case report

A case is reported of severe eye injury in an 11-year-old boy which occurred during threshing in the parents' farmyard. A detailed description of surgical treatment, complications and 7-year follow-up is presented. Despite long lasting treatment and new surgical methods used, the eye became blind. On the basis of our experience we can conclude that adequate adult supervision of children is mandatory during work in farmyards, and this is probably the only way to avoid at least a part of severe injuries which cause great social and economic losses.

Object localization, discrimination, and grasping with the optic nerve visual prosthesis

PURPOSE

This study involved a volunteer completely blind from retinis pigmentosa who had previously been implanted with an optic nerve visual prosthesis. The aim of this two-year study was to train the volunteer to localize a given object in nine different positions, to discriminate the object within a choice of six, and then to grasp it.

METHODS

In a closed-loop protocol including a head worn video camera, the nerve was stimulated whenever a part of the processed image of the object being scrutinized matched the center of an elicitable phosphene. The accessible visual field included 109 phosphenes in a 14 degrees x 41 degrees area.

RESULTS

Results showed that training was required to succeed in the localization and discrimination tasks, but practically no training was required for grasping the object. The volunteer was able to successfully complete all tasks after training. The volunteer systematically performed several left-right and bottom-up scanning movements during the discrimination task. Discrimination strategies included stimulation phases and no-stimulation phases of roughly similar duration.

CONCLUSION

This study provides a step towards the practical use of the optic nerve visual prosthesis in current daily life.

Standards for Modified Osteoodontokeratoprosthesis (OOKP) Surgery According to Strampelli and Falcinelli

PURPOSE

To establish a time-proven "gold standard" in modified osteoodontokeratoprosthesis (OOKP) surgery.

METHODS

The OOKP is the procedure of choice for restoring sight in patients with corneal blindness caused by end-stage ocular surface disease not amenable to penetrating keratoplasty. Members of the OOKP Study Group met in Rome, Italy in 2001 and Vienna, Austria in 2002 to discuss indications and contraindications, patient selection, surgical technique, postoperative care, and recognition and management of complications of OOKP surgery according to Strampelli and modified by Falcinelli.

RESULTS

Falcinelli's modification of Strampelli's technique of OOKP surgery remains the gold standard as far as visual and keratoprosthesis-retention results are concerned. The agreement on indications and contraindications, patient selection, surgical technique, postoperative care, and recognition and management of complications of this technique of OOKP surgery is summarized in the text of this manuscript.

CONCLUSION

This standard technique of modified OOKP surgery, where adequately performed, is capable of providing excellent anatomic and functional results even in the long term. In patients with corneal blindness untreatable by other approaches, we strongly recommend this technique for visual rehabilitation. Students of OOKP surgery should become familiar with the protocol described in this paper before subjecting the technique to further modifications.