Tube shunt complications and their prevention.

PURPOSE OF REVIEW: Glaucoma drainage devices (GDDs) have been generally accepted as a treatment of refractory glaucoma. GDDs have their own unique set of complications that are important to evaluate to prevent them. RECENT FINDINGS: Tube shunts are typically used in eyes with refractory glaucoma. There is increased interest in studying the efficacy of GDDs. Most of the attention has been focused on comparing trabeculectomy with the Baerveldt implant (Advanced Medical Optics, Inc., Santa Anna, California, USA). The other leading implant is the Ahmed Glaucoma Valve. There are several retrospective studies comparing these two devices and a prospective study is ongoing. There is great interest in the complication rate of tube shunts and these have been published both retrospectively and prospectively. Complications such as hypotony, diplopia, strabismus, proptosis, tube erosion, failure, corneal decompensation, endophthalmitis, and visual loss are all important and some have recently been reviewed in the literature. Moreover, the use of glaucoma drainage implants in the pediatric population has been evaluated. SUMMARY: Glaucoma drainage implants have been a powerful tool in our surgical fight to prevent blindness; however, they are not without complications or controversy.

Intraorbital Arteriovenous Fistula Presenting with Impaired Extraocular Movement After a Provocation Test at the Third Segment of the Ophthalmic Artery.

BACKGROUND: Distal catheterization in the ophthalmic artery beyond the origin of the central retinal artery has been attempted to avoid visual complications in cases of transarterial embolization (TAE). Although avoiding visual complications is important, extraocular complications have been rarely reported and discussed. Here, we report a case of an intraorbital arteriovenous fistula (AVF) presenting with impaired extraocular movement after a provocation test and discuss the potential risks associated with TAE at the third segment of the ophthalmic artery. CASE DESCRIPTION: A 53-year-old man was referred to our hospital for a newly diagnosed vascular lesion on the left optic chiasm. A left internal carotid angiogram revealed an intraorbital AVF fed by distal branches of the left ophthalmic artery taking a recurrent course toward the proximal ophthalmic artery, and the anterior branches of the inferior lateral trunk draining into the tortuous basal vein of Rosenthal with a varix. Neither the cavernous sinus nor the superior ophthalmic vein was opacified as draining routes of this lesion. A provocation test was done for diagnostic and therapeutic purposes at the third segment of the ophthalmic artery. During the test, the patient developed a transient impaired adduction of the left eye without any visual field deficit; therefore, TAE was avoided. The patient made an uneventful recovery and was recommended a transcranial transvenous embolization for a radical treatment. CONCLUSIONS: In intraorbital hypervascular lesions, occlusion of the third segment of the ophthalmic artery is associated with a potential risk of extraocular complications.

The inferior oblique muscle adherence syndrome.

OBJECTIVE: To describe the clinical features, etiology, prevention, and treatment of the inferior oblique muscle (IO) adherence syndrome. METHODS: This series consists of 12 patients treated for a restrictive hypotropia in which the middle portion of the IO was scarred anteriorly, either into or near the inferior rectus muscle (IR) insertion, after prior surgery. RESULTS: Among the 12 patients treated, the mean hypotropia of the affected eye was 18.1 +/- 7.2 prism diopters and the mean excyclotropia was 13.8 degrees +/- 3.3 degrees . Causes of the IO adherence syndrome included IR surgery (with or without prior IO myectomy) and scleral buckling surgery. The syndrome responded well to surgically releasing or myectomizing the incarcerated IO, combined with ipsilateral IR recession. CONCLUSIONS: The IO adherence syndrome is a complication of surgery on the IR or of scleral buckling surgery, which can result in a restrictive hypotropia and excyclotropia. It can be prevented by paying attention to the anatomic relationship between the IO and IR and can be effectively treated if it occurs.

Management of complications in neurotology.

Neurotologic and skull base surgery involves working around important neurovascular and neurotologic structures and can incur unwarranted complications. Knowledge of surgical anatomy, good preoperative planning, intraoperative monitoring, and excellent microsurgical technique contribute to minimizing and avoiding complications. In the event of a complication, however, the neurotologic surgeon should be prepared to manage it. In this article, the authors focus on the management of complications encountered in neurotologic skull base surgery, including hemorrhage, stroke, cerebrospinal fluid leak, extraocular motility deficits, facial paralysis, hearing loss, dizziness, lower cranial nerve palsies, and postoperative headache.

Preseptal transconjunctival approach for orbital floor fracture repair: ophthalmologic results in 209 patients.

CONCLUSIONS: The transconjunctival approach to orbital floor fractures permits excellent exposure of the inferior orbit and provides a good surgical outcome, especially with regard to ocular motility. OBJECTIVE: Surgical access to orbital floor fractures can be accomplished via the transconjunctival approach. The majority of studies on this subject deal with surgical aspects and complications. The purpose of this study was to report the ophthalmologic outcome after transconjunctival orbital floor fracture repositioning in a significant number of patients. MATERIAL AND METHODS: In a retrospective study, the data of 209 patients with orbital floor fractures treated via the transconjunctival approach with (n=181) and without (n=28) lateral canthotomy were analyzed. RESULTS: The commonest cause of injury was forms of violence (32%). An isolated fracture of the orbital floor had occurred in 62 cases, while concomitant facial fractures were present in the remaining 147. A total of 24 patients (11%) had an exophthalmos and 13 (9%) an enophthalmos. Most patients (69%) complained of infraorbital dysesthesia. When elevating the eyeball, the majority of patients showed a marked or severe disturbance of ocular motility (53% in abduction; 51% in adduction) and diplopia (37% in abduction; 36% in adduction). Thirteen patients required repeat surgery. After a follow-up period of 2 years, infraorbital dysesthesia was observed in only three patients, one of whom presented with a considerable persistent enophthalmos of 4 mm, and only four patients had persistent reduced motility and diplopia.

Orbital floor reconstruction with flexible Ethisorb patches: a retrospective long-term follow-up study.

OBJECTIVE: The purpose of the study was to investigate whether a flexible, biodegradable material (Ethisorb) shows better long-term results with regard to diplopia, bulbus motility, and exophthalmos/enophthalmos compared to the use of lyophilized dura-patches and polydioxanone (PDS) foils. METHODS: During a period of 6 years 435 patients with an orbital fracture were investigated retrospectively. Inclusion criteria were patients with fractures of the orbital floor with a maximum size of 2 x 2 cm. Bulbus motility, exophthalmos, enophthalmos, and diplopia were investigated during a period of 2 years. RESULTS: One hundred twenty orbital floors were reconstructed by lyophilized dura-patches, 81 by PDS, and 136 by Ethisorb. An exploration without an implantation was performed in 91 patients. The long-term investigation 12 to 15 months after surgery showed an exophthalmos and enophthalmos incidence of 1%, whereas a reduced bulbus motility and diplopia were found in 5% and 4%, respectively. Fifteen to 24 months after surgery 2% of the patients had an exophthalmos and 1% had an enophthalmos. A reduction of bulbus motility was found in 4% of the patients, and diplopia was found in 3%. The use of Ethisorb resulted in a significantly lower incidence of exophthalmos 3 months after surgery compared to PDS. CONCLUSION: The low rate of acquired bulbus motility demonstrates acceptable results in using Ethisorb in the floor of the orbit.

[Surgical eye muscle counter-rotation after macular translocation]. / Augenmuskelchirurgische Gegenrotation nach Makulatranslokation.

Surgical counter-rotation after macular translocation is indicated when a non-fusionable cyclodeviation exists by lack of suppression. Different surgical options exist to counter-rotate the globe after macular translocation. Primary angles of retinal rotation up to 40 degrees can be compensated for.

Experimentally designed glaucoma implant surgery with mitomycin C in rabbit.

An attempt was made to observe the possibility of controlling intraocular pressure (IOP) without hypotony and ocular motility disorder by installing an experimentally designed glaucoma implant through a small conjunctival incision with the aid of a stylet and maintaining the aqueous reservoir using mitomycin C (MMC). The implant was made of silicone tube, of which one end was occluded by glue and on the same end 4 check-valve-like slits were made. Thirty-five healthy white rabbits were used and subdivided into 4 groups. In groups I to III, implants having 2.0, 2.5, 3.0 mm slit lengths, respectively, were installed with MMC application in one eye of each of the 10 rabbits. In group IV, a 2 mm slit-length implant was installed without MMC in one eye of each of the 5 rabbits. Pneumatonometry and ultrasonography were performed to check the IOP and the formation of aqueous reservoir in the implanted eyes for 8 weeks. In group I through III, there was a statistically significant 4-5 mmHg pressure-lowering effect in the implanted eyes compared to the contralateral control eyes for 8 weeks. The aqueous reservoirs were observed throughout the follow-up period. In group IV, we could observe neither a pressure-lowering effect nor aqueous reservoir formation in the implanted eyes after 2 weeks postoperatively. Hypotony did not occur in implanted eyes in any of the groups. This study shows the possibility of IOP control by installing a specially designed glaucoma implant with application of MMC.

[Granular cell tumors of the orbit: diagnostics and therapeutic aspects exemplified by a case report]. / Granularzelltumor der Orbita: Diagnostische und therapeutische Aspekte anhand eines Fallberichtes.

BACKGROUND: Granular cell tumors (Abrikossoff's tumor) are very rare, mostly benign tumors of neurogenic origin which preferentially occur in the upper aerodigestive tract. Granular cell tumors rarely originate in the orbit and are therefore a diagnostic and therapeutic challenge. METHOD AND PATIENTS: A 42-year-old male patient presented to the Orthoptic Department of the University Eye Clinic in Salzburg with motility disturbances and diplopia in the right eye. The clinical examination revealed right-sided exophthalmos and shrinking of the choroid and retina due to a retrobulbar mass. The radiological examination showed an infiltrative tumor 1.7 × 1.3 cm in size in the lower temporal quarter of the orbit. Due to the localization a sonographically controlled fine needle puncture was carried out for preoperative diagnostics by a specialist in clinical cytology. The cytological examination confirmed the presence of a granular cell tumor. The tumor was excised via a conjunctival access route. RESULTS: Motility testing in the postoperative course control showed an improvement in the findings and the exophthalmos was clearly regressive. Vision improved from 0.5 preoperatively to 1.0 postoperatively. During the postoperative observational period of 12 months no recurrences occurred. Clinical control examinations are planned every 3 months and imaging controls every 6 months. CONCLUSION: Granular cell tumors of the orbit should be included in the differential diagnostics of orbital tumors despite the low incidence. A sonographically controlled fine needle puncture is an adequate procedure with respect to the diagnostics and further therapy for poorly differentiated tumors of the orbit with a suspicion of infiltrative growth and for which in toto resection is questionably possible. A complete surgical excision should be the aim of treatment of granular cell tumors. Continuous clinical and imaging control is necessary to enable early recognition of recurrences.

[Diagnosis of vertigo: keep an eye on central eye movement disorders]. / Diagnose von Schwindel mit besonderem Blick auf Augenbewegungsstörungen.

With specialist knowledge ophthalmologists can make a valuable contribution to the interdisciplinary work-up of patients with vertigo as the leading symptom. The neuro-ophthalmological examination of eye movements by an ophthalmologist and/or orthoptist is an important contribution because the various vertigo syndromes can only be correctly evaluated by a combined examination of the vestibular and ocular motor systems. If the ophthalmologist is the first doctor to examine a patient suspected disorders from other specialist fields can be indicated, in particular neurology and otorhinolaryngology. When taking the patient history the ophthalmologist should inquire about the type and duration of the vertigo, triggering or modifying factors and accompanying symptoms. This is followed by a systematic examination of the eye position and the different types of eye movements, the head-impulse test and a special examination to check for the presence of nystagmus.

[Vertigo and dizziness. Ophthalmological addendum]. / Schwindel. Ophthalmologisches Addendum.

The ophthalmologist's main task in the interdisciplinary approach to vertigo is the examination of ocular motility to rule out central ocular motility disorders. Further neuro-ophthalmological examinations (e.g. pupil reactions and optic disc) may provide unspecific findings that can be helpful. The ophthalmologist may be able to deliver puzzle-solving key findings in some multidisciplinary diseases (e.g. Cogan I, Vogt-Koyanagi-Harada disease and Behcet's disease). Ocular alterations do not cause vertigo but a variety of more diffuse complaints that some patients refer to as vertigo.

Screening for childhood strabismus by primary care physicians.

OBJECTIVE: To review the clinical classification of strabismus, to describe the timing and method of strabismus screening examinations, and to discuss the principles of treatment. QUALITY OF EVIDENCE: Current literature (1983 to 1995) was searched via MEDLINE using the MeSH headings strabismus, ocular motility disorders, and amblyopia. Articles were selected based on their date of publication, clinical relevance, and availability. Preference was given to more recent articles, articles with large numbers of subjects, and well-designed cohort studies. Official recommendations from academic groups were analyzed. Descriptions of clinical tests and their illustrations are based on classic texts. MAIN FINDINGS: Primary care physicians should screen all low-risk children. High-risk children (low birth weight, family history of strabismus, congenital ocular abnormality, or systemic conditions with vision-threatening ocular manifestations) should be referred to an ophthalmologist for screening. Screening should be performed in the neonatal period, at 6 months, and at 3 years (Grade A recommendation), as well as at 5 to 6 years (Grade B recommendation). Screening examination includes inspection, examining visual acuity, determining pupillary reactions, checking ocular alignment, testing eye movements, and ophthalmoscopy. CONCLUSIONS: Primary care physicians are essential to early detection of strabismus and amblyopia. Early detection can help minimize visual dysfunction, allow for normal development of binocular vision and depth perception, and prevent psychosocial dysfunction.

Neuro-ophthalmology of diabetes.

The devastating, blinding effects of diabetic retinopathy have been well publicized. Although individually less common, many neuro-ophthalmologic complications are also associated with diabetes. The vascular effects of diabetes contribute to nonarteritic ischemic optic neuropathy, vasculopathic cranial neuropathies, and strokes affecting both afferent visual function and ocular motility. The neuropathic effects of diabetes primarily affect pupillary function, and the immunosuppressive effects of diabetes predispose to certain infections, such as mucormycosis. Diabetes is also associated with numerous congenital syndromes. This paper reviews the literature published in the past year on the neuro-ophthalmologic effects of diabetes.