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An Approach to Oculomotor Anomalies in a Child
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
The three ocular motor nerves innervate the six extraocular muscles as well as the levator palpebrae superioris (LPS) and the pupillary constrictors. The oculomotor nerve innervates the LPS, superior rectus (SR), inferior rectus, medial rectus, inferior oblique, and the pupillary constrictors. The trochlear nerve innervates the superior oblique muscle, and the abducens nerve innervates the lateral rectus muscle. The pathways involved in supranuclear control of the ocular motor nerves descend from the cerebral cortex and terminate in the brainstem in the omnipause neurons (for horizontal saccades) and the rostral interstitial nucleus of the medial longitudinal fasciculus of the midbrain (vertical saccades).
3rd Cranial Nerve Palsy
Published in K. Gupta, P. Carmichael, A. Zumla, 100 Short Cases for the MRCP, 2020
K. Gupta, P. Carmichael, A. Zumla
The 3rd cranial nerve (oculomotor nerve) supplies the medial rectus, superior rectus and the inferior oblique muscles. In addition it supplies the pupilloconstrictor and levator palpebrae muscles. It is important to understand the exact role of the extraocular muscles in the movements of the eyeball. For example, if a patient with right-sided 3rd nerve palsy is asked to look straight, the right eye will turn laterally because of the unopposed action of the lateral rectus (supplied by the 6th nerve) and diplopia results. When the patient is asked to look to the far right, both eyes can move in the right direction. If the patient is asked to look to the far left, the right eye (with the 3rd nerve palsy) fails to cross the midline because of the failed action of the medial rectus and diplopia results.
Clinical features of isolated inferior rectus paralysis
Published in Jan-Tjeerd de Faber, 28th European Strabismological Association Meeting, 2020
The mean age of patients was 30.2 years (min: 6 max: 64 years) the aetiology was congenital in 3 patients and myastenia gravis in one patient. Three of 4 patients were female. The ophthalmologic examination and motility analysis were performed. Hypertropia was presenting symptom. Mean deviation of hypertropia was 18 prism diopters (range 8–25 prism diopters).Severe limitation in down-ward gaze, head posture, secondary deviation was revealed in examination. No other manifestation of partial third nerve involvement such as pupillary anomalies, ptosis were present. An associated exotropia (range 4–90 prism diopters) was present in all patients. Forced duction test was positive in three congenital patients who underwent surgical procedure. One patient required one operation, 2 had two. As an surgical approach, superior rectus recession and inferior rectus resection was performed in two eyes, but in one of them, combined lateral rectus recession was also performed for associated exotropia. In one patient, lateral rectus recession-medial rectus resection with infraplasman and superior rectus recession and contralateral inferior rectus recession was performed. The mean postoperative deviation of hypertropia was 5 prism diopters (0 to 12). Postoperatively, ductions of affected eye were improved in three patients The patient who developed sudden onset of vertical diplopia especially in downward gaze had diabetes mellitus and myastenia gravis. The ocular finding of patients was shown in table 1.
Automated Measurement of Ocular Movements Using Deep Learning-Based Image Analysis
Published in Current Eye Research, 2022
Lixia Lou, Yiming Sun, Xingru Huang, Kai Jin, Xiajing Tang, Zhaoyang Xu, Qianni Zhang, Yaqi Wang, Juan Ye
Clinical assessment of ocular movements is essential for the diagnosis and management of ocular motility disorders, and particularly important in incomitant strabismus. Six cardinal positions of gaze are identified in which one muscle in each eye is principally responsible for moving the eye into that position as follows: adduction (medial rectus [MR]), abduction (lateral rectus [LR]), suprabduction (superior rectus [SR]), supraduction (inferior oblique [IO]), infraduction (inferior rectus [IR]), and infraduction (superior oblique [SO]).1 Traditionally, clinicians grade hyperfunction and hypofunction of extraocular muscles using a qualitative scale based on subjective criteria, so much of that depend on clinicians’ experience.2,3 To circumvent this problem, many quantitative methods either kinetic (e.g. the limbus test and the lateral version light-reflex test) or static (e.g. Hess and Lancaster screen) have been proposed, although no method has been advocated in the literature as the gold standard.4 Mai described a modified limbus test measuring maximal distances from the limbus to the eyelid margin at an angle of 45 degrees to the horizontal in the positions of suprabduction, supraduction, infraduction, and infraduction, as intuitive reflections of the function of vertical rectus and oblique muscles.5 This method avoids complicated measurement and calculation of the angle of ocular movements and thus could be easily and conveniently implemented in clinical practice.
Nasal insertion of the superior oblique tendon presenting as Brown syndrome
Published in Strabismus, 2022
Ahmed Awadein, Ahmed Adel Youssef, Jylan Gouda
Nasal insertion of the superior oblique was reported before in cases with congenital fibrosis of extraocular muscles. Brodsky, while discussing the surgical management of the congenital fibrosis syndrome, reported a case where surgical exploration revealed anomalous superior oblique tendons.2 The right superior oblique tendon consisted of tight, bifid structure which was anteriorly displaced, and which resembled muscle rather than tendon. The left superior oblique tendon also resembled muscle and was attached posteriorly under the temporal border of the superior rectus muscle. In both eyes, the superior oblique tendons were recessed and transposed anteriorly to the temporal border of the superior rectus muscle, which markedly reduced the patient’s divergence in downgaze. Sener and colleagues described the surgical management of 52 cases of congenital fibrosis of the extraocular muscles; they mentioned 3 cases of heterotopic superior oblique muscles inserting 0–4 mm nasal and posterior to the superior rectus insertion.3 Hunter et al. also reported anomalous superior oblique tendon insertion in congenital fibrosis of extraocular muscles.4 They described seven cases with an anomalously inserted superior oblique tendon, identified immediately adjacent and nasal to the superior rectus muscle rather than in its usual location in the superotemporal fornix.
Single-stage Orbital Decompression, Strabismus and Eyelid Surgery in Moderate to Severe Thyroid Associated Orbitopathy
Published in Orbit, 2022
Francesco M. Quaranta-Leoni, Matteo Di Marino, Antonella Leonardi, Sara Verrilli, Raffaello Romeo
Visual acuity improved in all patients who had experienced a decrease prior to surgery (Table 2). One patient needed steroid treatment for recurrent DON 11 months following surgery with full vision recovery. One patient presented with complete visual loss in her right eye of 2 months’ duration, right infraduction deficit and restrictive hypertropia, and progressive visual loss in her left eye, with elevation deficit, and a history of hyperglycemia, chronic gastric ulcer, and previous treatment with steroids. Visual acuity was no perception of light in her right eye, with a pale disc, and count fingers with a normal optic disc in her left eye. Following bilateral medial decompression with simultaneous right superior rectus recession and left inferior rectus recession, visual acuity improved to 20/400 in her right eye, and to 20/60 in her left eye (Figure 1).