Traitement chirurgical de la diplopie secondaire à l'orbitopathie dysthyroïdienne [Surgical treatment of diplopia in Graves' orbitopathy]

BACKGROUND: The correction of oculomotor disorder in Grave's disease is applied on pathological extraocular muscles. Based on the global muscular restriction (bilateral forced duction test) and angular measurements, we have used a non-adjustable technique. PATIENTS AND METHODS: We performed a retrospective analysis of 21 patients (23 operations) with thyroid-associated orbitopathy operated for persisting diplopia. The angles of deviation in the 9 diagnostic directions of gaze and the field of binocular vision were measured with the Harm's tangent scale before and after surgery. Sixteen patients were operated only on vertical muscles. The mean follow-up was 45 months. RESULTS: 76 % of the patients (95 % confidence interval [CI], 58-94 %) obtained a large and centred field of binocular vision without prisms. 14 % (95 % CI, 0-29 %) had binocular vision with the use of prisms. Diplopia persisted in one patient despite 3 operations. Taking into consideration the interventions done before the patient was referred to us, the reintervention rate was 13 % (95 % CI, 0-28 %). CONCLUSIONS: A binocular field of vision can be successfully restored in the majority of patients with Graves' orbitopathy, using a non-adjustable surgical technique.

Management of diplopia secondary to neurosurgical injury of the orbital roof

BACKGROUND: Diplopia related to neurosurgical procedures is often consecutive to oculomotor nerve lesions. We hereby report an oculomotor dysfunction secondary to an orbital roof effraction and its treatment. HISTORY AND SIGNS: Following surgery for a left anterior communicating artery aneurysm, a 45-year-old woman reported vertical diplopia associated with a left orbital hematoma. The diagnosis of third cranial nerve palsy was excluded by orbital imaging which revealed an orbital roof defect with incarceration of the levator palpebrae and superior rectus. THERAPY AND OUTCOME: As neurosurgeons advised against muscle adhesiolysis, diplopia was corrected by a two-step procedure on the oculomotor muscles. We first corrected horizontal and torsional deviations by operating on the healthy eye, before correcting the vertical deviation on the fellow eye. This two-step extraocular muscle surgery allowed restoration of binocular single vision in a useful field of gaze. CONCLUSIONS: Diplopia can occur as a rare orbital complication during neurosurgical procedures. Surgery of extraocular muscles can provide good functional results

Os primeiros trabalhos de Merleau-Ponty: convergência filosófica e diplopia metodológica

The discussion of different themes revealed in the initial works of Merleau-Ponty, which are especially relevant in debates on the foundations of psychology, demands a closer look at the strategically complicity, from a psychological viewpoint, between The Structure of Behavior and the Phenomenology of perception. That context constitutes the background for this article. Based on the prerogative of this complicity, the goal is to present a reading that highlights primordial issues to outline the philosophical intention of that author. Despite the use of distinct methodological perspectives, both are part of one single work project. They fit into the discussion of Cartesian antinomies in philosophy and depart from the delimitation of the same problem, i.e. that of perception, as a point of integration between the two fundamental orders of Descartes’ thinking: the soul and the body.

Cosmetic Orbital Inferomedial Decompression: Quantifying the Risk of Diplopia Associated With Extraocular Muscle Dimensions

Purpose: To quantify the risk of new diplopia in inferomedial orbital decompression performed for cosmetic reasons. Methods: Retrospective analysis of 114 patients with Graves orbitopathy who underwent an inferomedial orbital decompression. No patient had diplopia in any of the gaze positions or optic neuropathy. A single coronal slice 9 mm posterior to the lateral orbital rim was employed to quantify the muscular index of the extraocular recti and of the superior complex. A control group of 56 patients imaged for other reasons were also measured. After surgery the oculomotor status of all patients who complained of diplopia and of 51 patients free of diplopia was measured with the prism and cover test in the primary and secondary gaze positions. Results: The rate of new-onset diplopia was 14.0% (16 patients). Eye deviations were confirmed in 14 patients. Of these, 10 had significant strabismus that warranted surgical or prism treatment. Most patients had esotropia associated with small vertical deviations. The size of the medial and inferior recti was significantly associated with the development of diplopia. The estimated odds for the appearance of diplopia in patients with muscle enlargement was 12.76 (medial rectus) and 5.21 (inferior rectus). Small-angle deviations were also detected in 27.4% of patients who did not experience diplopia. Conclusions: Medial and inferior recti enlargement is a strong predictor of new-onset diplopia. A large number of patients who do not report diplopia also present with small-angle deviations. (Ophthal Plast Reconstr Surg 2012;28:204-207)

Binocular fusion, suppression and diplopia for blurred edges

Purpose: (1) To devise a model-based method for estimating the probabilities of binocular fusion, interocular suppression and diplopia from psychophysical judgements, (2) To map out the way fusion, suppression and diplopia vary with binocular disparity and blur of single edges shown to each eye, (3) To compare the binocular interactions found for edges of the same vs opposite contrast polarity. Methods: Test images were single, horizontal, Gaussian-blurred edges, with blur B = 1-32 min arc, and vertical disparity 0-8.B, shown for 200 ms. In the main experiment, observers reported whether they saw one central edge, one offset edge, or two edges. We argue that the relation between these three response categories and the three perceptual states (fusion, suppression, diplopia) is indirect and likely to be distorted by positional noise and criterion effects, and so we developed a descriptive, probabilistic model to estimate both the perceptual states and the noise/criterion parameters from the data. Results: (1) Using simulated data, we validated the model-based method by showing that it recovered fairly accurately the disparity ranges for fusion and suppression, (2) The disparity range for fusion (Panum's limit) increased greatly with blur, in line with previous studies. The disparity range for suppression was similar to the fusion limit at large blurs, but two or three times the fusion limit at small blurs. This meant that diplopia was much more prevalent at larger blurs, (3) Diplopia was much more frequent when the two edges had opposite contrast polarity. A formal comparison of models indicated that fusion occurs for same, but not opposite, polarities. Probability of suppression was greater for unequal contrasts, and it was always the lower-contrast edge that was suppressed. Conclusions: Our model-based data analysis offers a useful tool for probing binocular fusion and suppression psychophysically. The disparity range for fusion increased with edge blur but fell short of complete scale-invariance. The disparity range for suppression also increased with blur but was not close to scale-invariance. Single vision occurs through fusion, but also beyond the fusion range, through suppression. Thus suppression can serve as a mechanism for extending single vision to larger disparities, but mainly for sharper edges where the fusion range is small (5-10 min arc). For large blurs the fusion range is so much larger that no such extension may be needed. © 2014 The College of Optometrists.

Binocular summation, binocular fusion and the transition to diplopia

The visual system combines spatial signals from the two eyes to achieve single vision. But if binocular disparity is too large, this perceptual fusion gives way to diplopia. We studied and modelled the processes underlying fusion and the transition to diplopia. The likely basis for fusion is linear summation of inputs onto binocular cortical cells. Previous studies of perceived position, contrast matching and contrast discrimination imply the computation of a dynamicallyweighted sum, where the weights vary with relative contrast. For gratings, perceived contrast was almost constant across all disparities, and this can be modelled by allowing the ocular weights to increase with disparity (Zhou, Georgeson & Hess, 2014). However, when a single Gaussian-blurred edge was shown to each eye perceived blur was invariant with disparity (Georgeson & Wallis, ECVP 2012) – not consistent with linear summation (which predicts that perceived blur increases with disparity). This blur constancy is consistent with a multiplicative form of combination (the contrast-weighted geometric mean) but that is hard to reconcile with the evidence favouring linear combination. We describe a 2-stage spatial filtering model with linear binocular combination and suggest that nonlinear output transduction (eg. ‘half-squaring’) at each stage may account for the blur constancy.

The relationship between fusion, suppression, and diplopia in amblyopia

Purpose: Traditionally, it has been thought that no binocular combination occurs in amblyopia. However, there is a growing body of evidence that there are intact binocular mechanisms in amblyopia rendered inactive under normal viewing conditions due to imbalanced monocular inputs. Georgeson and Wallis (2014) recently introduced a novel method to investigate fusion, suppression and diplopia in normal population. We have modified this method to assess binocular interactions in amblyopia. Methods: Ten amblyopic and ten control subjects viewed briefly-presented (200 ms) pairs of dichoptically separated horizontal Gaussian blurred edges. Subjects reported one central edge, one offset edge, or a double edge as the vertical disparity was manipulated. The experiment was conducted at a range of spatial scales (blur widths of 4, 8, 16, and 32 arc min) and contrasts. Our model, based Georgeson and Wallis (2014), converted subjects’ responses into probabilities of fusion, suppression, and diplopia. Results: When the normal participants were presented equal contrast to each eye the probability of fusion gradually decreased with increasing disparity, as the probability of diplopia gradually increased. In only a small proportion of the trials, normal participants experienced suppression. The pattern was consistent across all edge blurs. Interestingly, the majority of amblyopes had a comparable pattern of fusion, i.e. decreasing probability with increasing disparity. However, with increasing disparity the amblyopes tended to suppress the amblyopic eye, experiencing diplopia only in a small proportion of trials particularly at large blurs. Increasing the interocular contrast offset favouring the amblyopic eye normalized the pattern of data in a way similar to normal participants. There were some interesting exceptions: strong suppressors for which our contrast range was inadequate and one case in which diplopia dominated. Conclusions: This task is suitable for assessing binocular interactions in amblyopic participants and providing a way to quantify the relationship between fusion, suppression and diplopia. In agreement with previous studies, our data indicate the presence of binocular mechanisms in amblyopia. A contrast offset favouring the amblyopic eye normalizes the measured binocular interactions in the amblyopic visual system.

Orbital apex syndrome due to aspergillosis: case report

We report the case of a 73-year-old female who presented facial numbness and pain in the first division of the trigeminal nerve, ptosis, diplopia and visual loss on the right side for the previous four months. The neurological, radiological and histological examination demonstrated a rare case of invasive fungal aspergillosis of the central nervous system, causing orbital apex syndrome, later transformed in temporal brain abscess. She died ten months later due to respiratory and renal failure in spite of specific antimycotic therapy.

Orbital abscess after facial trauma

This paper reports a rare case of acute severe orbital abscess manifested 2 days after a facial trauma without bone fracture in a 20-year-old Afro-American female. The symptoms worsened within the 24 h prior to hospital admission resulting in visual disturbances such as diplopia and photophobia. The clinical findings at the first consultation included fever, periorbital swelling and redness, ptosis, proptosis and limitation of ocular movements upwards, downwards, to the right and to the left. Computed tomography scan showed proptosis with considerable soft tissue swelling on the left side and no fracture was evidenced in the facial skeleton, including the zygomatic-orbital complex. After hospital admission and antibiotic therapy intravenously the patient was conducted to the operation room and submitted to incision and drainage under general anesthesia. The orbit was approached thorough both eyelids and the maxillary sinus was reached only through the Caldwell-Luc approach. The postoperative period was uneventful and the rapid improvement of symptoms was remarkable. Visual acuity and ocular motility returned to the normal ranges within 2 days after the surgical intervention. After 12 postoperative days, the patient presented with significative improvement in the ptosis and proptosis, and acceptable scars.

Charcot`s arthropathy secondary to herpetic encephalitis sequelae: an unusual presentation

Neuropathic arthropathy (Charcot`s arthropathy) is a progressive articular disease associated with a reduced sensorial and protector proprioceptive reflex. Its etiology includes many different conditions such as syringomyelia, traumatic lesion causing medullary deformity, spina bifida, diabetic neuropathy, leprosy neuropathy, neurofibromatosis, amyloid neuropathy, alcohol, and repetitive injection of hydrocortisone into joints, among others. However, the relationship between Charcot`s arthropathy and herpetic encephalitis has not yet been described. Herpes encephalitis causes acute and chronic diseases of the peripheral or central nervous system. It can manifest as subacute encephalitis, recurrent meningitis, or myelitis. It can also resemble psychiatric syndromes, diplopia, sensory changes in the face and limbs, personality changes, frontal dysexecutive syndrome, stiff neck, subclinical alterations of the vestibular function, intracranial hypertension, convulsion, hemiparesis, and generally includes motor components, among others. On the other hand, pure peripheral sensory disturbance has not been described. In this article, we report the clinical case of a patient with Charcot`s arthropathy secondary to pure peripheral sensory polyneuropathy as a consequence of progressive herpetic encephalitis sequelae. In this article, the authors report the first case of Charcot`s arthropathy secondary to herpetic encephalitis.

Surgical removal of small petroclival meningiomas

Treatment of large petroclival meningiomas causing brain stem compression is surgical removal followed by radiotherapy or radiosurgery if the lesion was partially resected. The management of small petroclival meningiomas is, however, controversial. Clinical observation, radiosurgery and surgical removal are the options of treatment. The natural history of these tumours is not well known. Published series of patients treated with radiosurgery are not comparable with surgical series because the latter also includes large size tumours. In this paper we present a series of 18 patients with small petroclival meningiomas (diameter <= 2.8cm) treated with radical surgical removal. Total resection (Simpson`s Grade 1) [43] was possible with minimal morbidity and no mortality. Background. We present a series of small petroclival meningiomas (SPM) treated by radical surgical removal and compare the outcome with other management modalities proposed for these lesions. Methods. Eighteen patients with SPM were surgically treated at our department of neurological surgery. The tumours were classified as small when they had a diameter < 3.0cm. Headaches (n = 12), diplopia (n = 8), facial hypoaesthesia (n = 3) and tinnitus (n = 6) were the most frequent symptoms at presentation. The approaches used were retrosigmoid (n = 14), fronto-orbito-zygomatic (n = 3) and presigmoid (n = 1). The post-operative follow-up ranged from 1 to 110 months (mean 41.8 months). Findings. Radical tumour resection (Simpson`s Grades 1 and 2) was achieved in all patients. There was no major morbidity or mortality related to the surgical procedure. Transient abducent nerve palsy was the only post-operative complication. The pre-operative cranial nerves deficits improved after surgery. Only one patient had persistent diplopia postoperatively. Conclusion. Radical surgical removal of SPM is possible with minimal morbidity and may cure the patient. The effectiveness and outcome of surgery for small petroclival meningiomas should be compared with series treated by radiosurgery.

Fractured Orbital Wall Reconstruction With an Auricular Cartilage Graft or Absorbable Polyacid Copolymer

Objective: The objective of the study was to compare the functional and aesthetic results of fractured orbital wall reconstruction with an auricular cartilage graft or absorbable polyacid copolymer. Materials and Methods: Twenty patients with blow-out orbital fracture/orbital floor associated or not with the medial wall were assessed by the same craniofacial surgical group. All were evaluated preoperatively and postoperatively by an ophthalmologist for diplopia, enophthalmos, exophthalmos, sensitivity, ophthalmic reflexes, intraocular pressure, and visual field. The patients were subjected to a preoperative facial multislice computed tomographic scan, repeated 6 months after surgery. Eight patients underwent reconstruction with an auricular cartilage graft, and 12 patients, with blade absorbable polyacid copolymer. Subtarsal access was used for all patients. Results: Two patients showed temporary ectropion, 1 in each group. All patients presented satisfactory ocular function, and all tests revealed good orbital delineation, orbital symmetry, periorbital sinus individualization, and reduction of blow-out. Conclusions: The blow-out orbital wall reconstruction can be performed with the use of an auricular cartilage or with a blade absorbable copolymer without differences regarding functional or aesthetic complications and sequelae.

Superior oblique muscle amyloidosis mimicking myositis

A 47-year-old man presented with complaints of progressive diplopia in downgaze and a painful firm mass on the left medial superior canthus. On examination, there was marked hyperemia of the superior bulbar conjunctiva of the left eye. Systemic examination revealed erythematous papules on his trunk and pulmonary infiltrates. CT of the orbits revealed a fusiform enlargement of the left superior oblique muscle and diffuse infiltration of the left temporal region. Biopsy of the left superior oblique muscle and temporal muscle disclosed Congo red deposits that show apple-green birefringence under polarized light. A comprehensive systemic investigation failed to show any disease that could explain the amyloid deposits. The patient was then diagnosed as having primary systemic amyloidosis. We think that this case highlights the necessity of a biopsy in any atypical extraocular muscle enlargement before a diagnosis of myositis.