Superior Rectus Research Articles

Single horizontal rectus muscle vertical augmented transposition with posterior fixation suture in management of monocular elevation deficiency

ABSTRACT We describe successful management of three cases of acquired monocular elevation deficiency (MED) with superior transposition of the lateral rectus augmented with a posterior fixation suture with or without simultaneous inferior rectus muscle weakening. In each case, the lateral rectus muscle was transposed superiorly to the superior rectus muscle along the spiral of Tillaux, with maintained distance between the original lateral rectus muscle poles and the limbus. Augmentation was achieved with a posterior fixation suture 8 mm posterior to the muscles’ insertion. At the time of lateral rectus transposition, simultaneous inferior rectus recession by 5.5 mm was performed in case 1 whereas simultaneous botulinum toxin injection was performed in case 3. With regards to all three cases, the mean age was 32 years [10–46 years] and the mean follow-up period was 10 months. The mean hypotropia was reduced from 35 prism diopters (PD) (range: 20 to 60 PD) to 4.67 PD (range: 0 to 14 PD) with a mean correction of 32.57 ± 9.34 PD after 9 months. In our experience, full-tendon-width transposition of the lateral rectus to the superior rectus with posterior fixation suture corrects primary position hypotropia in MED and does not always require simultaneous inferior rectus recession. When transposing the lateral rectus muscle along the spiral of Tillaux, the measured distance of the original muscle insertion point to the limbus must be maintained in order to prevent recession of the muscle.

Surgical strategy for third nerve palsy with aberrant regeneration: Harnessing the aberrant power.

Purpose:Our study aimed to evaluate the outcome of contralateral eye (CE) fixation duress squint surgery (FDSS) in third nerve palsy (3rd NP) with aberrant regeneration and compare the postoperative ptosis correction with preoperative ptosis improvement on adduction.Methods:Patients of 3rd NP with aberrant regeneration who underwent CE FDSS between December 2012-July 2015 in a tertiary-care eye hospital with a follow-up period of 1-year were retrospectively studied to analyze preoperative and postoperative details. Surgical success was defined as the correction of ptosis within 1 mm of preoperative ptosis improvement during maximal adduction of the affected eye, postoperative alignment ≤10Δ, and resolution of subjective diplopia in primary position.Results:A total of 14 eyes in 14 patients (mean age 23.6 ± 13.6 years) were included. Mean preoperative exotropia and ptosis in primary position in 14 patients was 53.4 ± 20pd and 4.89 ± 2.9 mm, respectively, and mean hypotropia in 6 patients was 23.67 ± 5.89pd. The mean improvement of ptosis on adduction and supraduction in all patients was 4.07 ± 2.64 mm and 2.89 ± 2.22 mm, respectively (P = 0.213). All patients underwent large recession of CE lateral rectus (mean 12.4 ± 2.7 mm), 9 patients underwent CE medial rectus resection/plication (mean 6.0 ± 0.9 mm) and 6 patients underwent CE superior rectus recession (mean 6.6 ± 0.67 mm). Postoperatively, mean ptosis and exotropia correction was 3.7 ± 2.4 mm (P = 0.000) and 15 ± 9.6pd (P = 0.000), respectively, and mean hypotropia was 2.17 ± 4.02pd (P = 0.000). Surgical success was achieved in 6 patients. Postoperative ptosis correction showed strong positive correlation with preoperative improvement of ptosis on adduction (r = 0.87; P = 0.00).Conclusion:Preoperative lid excursion on adduction in 3rd NP can be regarded as a prognostic sign of the success of CE FDSS which can simultaneously correct both ptosis and squint.

To Study Presentation of Ocular Cysticercosis and Evaluate Its Demographic Data, Diagnosis, Treatment and Outcome in a Hill Population of Northern India

<i>Aim:</i> To study presentation of ocular cysticercosis and to evaluate its demographic data, diagnosis, treatment and outcome in hill population of Northern India. <i>Materials and methods:</i> This is a retrospective study carried out in Dehradun, Uttarakhand in a tertiary eye care hospital over 4 years from 2016-2020. The study involved 38 patients who presented with unilateral eye disease and were diagnosed to have ocular or adenexal cysticercosis. We analysed retrospectively their geographical data, clinical presentation, serology, imaging, response to treatment and clinical outcome. <i>Results:</i> Age of patients ranged from 16-54 years. Male to female ratio was 1:3.75. Total no. of eyes affected were 38. All were unilateral presentation. 30 eyes (78.94%) presented with extraocular cysticercosis and 8 eyes (21.05%) with intraocular cysticercosis. 27 of the patients (71.05%) were from lower socioeconomic status with poor hygiene and sanitation conditions. 32 (89.21%) patients gave history of association with non-vegetarian diet. Extraocular cysticercosis group had restriction of ocular motility as most prevalent presentation seen in 16 eyes (53.33%) and proptosis as the most prevalent sign seen in 17 eyes (56.66%). Cyst prevalence was most frequently detected in superior rectus muscle seen in 14 eyes (53.84%). Intraocular cysticercosis group had blurring of vision as the most prevalent presenting symptom in 8 eyes (100.0%). Panuveitis in 6 eyes (75%) and presence of subretinal cyst in 4 eyes (50%) was the most prevalent sign seen in intraocular cysticercosis group. Enzyme linked immunosorbent assay test confirmed serology in 35 cases (92.10%). The USG B-scan detected presence of scolex in 36 eyes (94.73%). Magnetic resonance imaging (MRI) confirmed deep seated extraocular cysticercosis lesions and neurocysticercosis (NCC) undetected by computerized tomography (CT). CT was diagnostic for NCC in 5 cases (13.15%). Oral Albendazole and prednisolone were successful in management of extraocular cysticercosis. Intraocular cysticercosis was treated well with pars plana vitrectomy surgery with good visual recovery. <i>Conclusion:</i> Extraocular cysticercosis was more prevalent than intraocular cysticercosis. Early diagnosis and treatment made a difference in final outcome of the two groups. Imaging studies of orbital B-scan ultrasonography (USG B scan), CT and MRI with immune serological test of enzyme linked immunosorbet assay (ELISA) and Western blot for anticysticercus antibodies helped in confirming the diagnosis. Extraocular cysticercosis can be managed well medically with good clinical outcome. Intraocular cysticercosisis is best treated surgically. Safer and modern vitreoretinal surgical techniques promise good surgical outcome and visual recovery. Timely intervention and frequent postoperative follow up would help in keeping a watch on development of complications and maintenance of good vision.

Cerebellar projections to the macaque midbrain tegmentum: Possible near response connections.

Since most gaze shifts are to targets that lie at a different distance from the viewer than the current target, gaze changes commonly require a change in the angle between the eyes. As part of this response, lens curvature must also be adjusted with respect to target distance by the ciliary muscle. It has been suggested that projections by the cerebellar fastigial and posterior interposed nuclei to the supraoculomotor area (SOA), which lies immediately dorsal to the oculomotor nucleus and contains near response neurons, support this behavior. However, the SOA also contains motoneurons that supply multiply innervated muscle fibers (MIFs) and the dendrites of levator palpebrae superioris motoneurons. To better determine the targets of the fastigial nucleus in the SOA, we placed an anterograde tracer into this cerebellar nucleus in Macaca fascicularis monkeys and a retrograde tracer into their contralateral medial rectus, superior rectus, and levator palpebrae muscles. We only observed close associations between anterogradely labeled boutons and the dendrites of medial rectus MIF and levator palpebrae motoneurons. However, relatively few of these associations were present, suggesting these are not the main cerebellar targets. In contrast, labeled boutons in SOA, and in the adjacent central mesencephalic reticular formation (cMRF), densely innervated a subpopulation of neurons. Based on their location, these cells may represent premotor near response neurons that supply medial rectus and preganglionic Edinger-Westphal motoneurons. We also identified lens accommodation-related cerebellar afferent neurons via retrograde trans-synaptic transport of the N2c rabies virus from the ciliary muscle. They were found bilaterally in the fastigial and posterior interposed nuclei, in a distribution which mirrored that of neurons retrogradely labeled from the SOA and cMRF. Our results suggest these cerebellar neurons coordinate elements of the near response during symmetric vergence and disjunctive saccades by targeting cMRF and SOA premotor neurons.

Superior colliculus projections to target populations in the supraoculomotor area of the macaque monkey.

A projection by the superior colliculus to the supraoculomotor area (SOA) located dorsal to the oculomotor complex was first described in 1978. This projection's targets have yet to be identified, although the initial study suggested that vertical gaze motoneuron dendrites might receive this input. Defining the tectal targets is complicated by the fact the SOA contains a number of different cell populations. In the present study, we used anterograde tracers to characterize collicular axonal arbors and retrograde tracers to label prospective SOA target populations in macaque monkeys. Close associations were not found with either superior or medial rectus motoneurons whose axons supply singly innervated muscle fibers. S-group motoneurons, which supply superior rectus multiply innervated muscle fibers, appeared to receive a very minor input, but C-group motoneurons, which supply medial rectus multiply innervated muscle fibers, received no input. A number of labeled boutons were observed in close association with SOA neurons projecting to the spinal cord, or the reticular formation in the pons and medulla. These descending output neurons are presumed to be peptidergic cells within the centrally projecting Edinger-Westphal population. It is possible the collicular input provides a signaling function for neurons in this population that serve roles in either stress responses, or in eating and drinking behavior. Finally, a number of close associations were observed between tectal terminals and levator palpebrae superioris motoneurons, suggesting the possibility that the superior colliculus provides a modest direct input for raising the eyelids during upward saccades.

Large-angle hypertropia managed by modified Nishida's procedure

Treating vertical squints especially large-angle hypertropia caused by inferior rectus palsy is a challenge. Superior rectus recession in presence of positive forced duction tests is the first step in surgical management. Following this, full tendon transposition of horizontal recti inferiorly (Inverse Knapp's procedure) is the standard procedure of choice. Modified Nishida's procedure has been described to treat vertical deviations like MED and inferior rectus aplasia. We describe a case of large-angle hypertropia treated by Modified Nishida's procedure.

Shape analysis of rectus extraocular muscles with age and axial length using anterior segment optical coherence tomography

PurposeThis study aimed to evaluate the shape of the extraocular muscles (EOMs) in normal subjects using the en-face images of anterior segment optical coherence tomography (AS-OCT). The EOM insertion and the direction of the muscle fibers were investigated.Subjects and methodsA total of 97 healthy normal subjects (194 eyes) at Okayama University Hospital (age, 47.1±21.5 years; range, 8–79 years) participated in the study. A series of 256 tomographic images of the rectus EOMs were captured using the C-scan function of the AS-OCT (CASIA2, TOMEY Co., Japan), and the images were converted to en-face images in multi-TIFF format. The anterior chamber angle to EOM insertion distance (AID) and the angle of the muscle fibers from the insertion site (angle of muscles) were measured from the images. The correlations of AID and angle of muscles with age and axial length were investigated and evaluated.ResultsAID and angle of muscles were significantly correlated with age or axial length in some EOMs. The AIDs of medial rectus (MR) (P = 0.000) and superior rectus (SR) (P = 0.005) shortened with age. The AIDs of MR (P = 0.001) and inferior rectus (IR) (P = 0.035) elongated with axial length, whereas lateral rectus (LR) (P = 0.013) shortened. The angles of MR (P = 0.001) and LR (P = 0.000) were found to have a more downward direction toward the posterior in older subjects.ConclusionEn-face images can be created by AS-OCT, and the shape of the EOMs in normal subjects using these image measurements was available. With the ability to assess the EOMs, AID and angle of muscles are expected give useful information for treating and diagnosing strabismus-related diseases.

Orbital decompressive effect of endoscopic transorbital surgery for sphenoorbital meningioma.

This study was aimed at evaluating the orbital decompressive effect of endoscopic transorbital approach (TOA) in the management of sphenoorbital meningioma involving the orbit. Patients treated with TOA for this tumor from December 2016 to December 2019 were included, and the data were reviewed. Pre- and postoperative clinical and imaging findings were compared with a volumetric study. Eighteen patients (two men and 16 women) were included. Lateral wall hyperostosis (13 patients), extraconal tumor infiltration (18 patients), intraconal tumor infiltration (seven patients), and superior and lateral rectus encasement (nine patients) were found. Intraconal tumor infiltration in the posterior orbit affected compressive optic neuropathy (CON) more often than other tumor manifestations. The orbital soft tissue volume decreased to 91.18% ± 8.19% compared to that in the contralateral side preoperatively. The postoperative volume increased to 113.73% ± 12.92% compared to the preoperative volume. The average values of LogMAR visual acuity and visual field index score of ten patients with CON improved from 0.80 to 0.42 and 48.9 to 65.9%, respectively. All 17 patients with proptosis showed improvement after surgery. There were no significant complications associated with the surgery. Additional treatment, including gamma knife surgery, was applied to 12 cases for the remaining tumor. This minimally invasive surgical debulking procedure was successful in treating sphenoorbital meningioma without significant adverse events. Lateral orbital wall decompression and limited intraorbital tumor resection were effective for compressive orbitopathy from the tumor.

Correlation of Automated Computed Tomography Volumetric Analysis Metrics With Motility Disturbances in Thyroid Eye Disease.

The authors sought to examine relationships between CT metrics derived via an automated method and clinical parameters of extraocular muscle changes in thyroid eye disease (TED). CT images of 204 orbits in the setting of TED were analyzed with an automated segmentation tool developed at the institution. Labels were applied to orbital structures of interest on the study images, which were then registered against a previously established atlas of manually indexed orbits derived from 35 healthy individuals. Point-wise correspondences between study and atlas images were then compared via a fusion algorithm to highlight metrics of interest where TED orbits differed from healthy orbits. Univariate analysis demonstrated several correlations between CT metrics and clinical data. Metrics pertaining to the extraocular muscles-including average diameter, maximum diameter, and muscle volume-were strongly correlated (p < 0.05) with the presence of ocular motility deficits with regards to the superior, inferior, and lateral recti (with exception of superior rectus motility deficits being mildly correlated with muscle volume [p = 0.09]). Motility defects of the medial rectus were strongly correlated with muscle volume, and only weakly correlated with average and maximum muscle diameter. The novel method of automated imaging metrics may provide objective, rapid clinical information which may have utility in prevention and recognition of visual impairments in TED before they reach an advanced or irreversible stage and while they are able to be improved with immunomodulatory treatments.

Examination of the Annular Tendon (Annulus of Zinn) as a Common Origin of the Extraocular Rectus Muscles: 2. Embryological Basis of Extraocular Muscles Anomalies

PurposeMany reports have described anomalous connections of the superior rectus (SR) with other extraocular rectus muscles, in which additional heads of the other three rectus muscles likely provided the connections. We examined how these connections are established during fetal development.MethodsWe analyzed paraffin-embedded horizontal sections from 25 late-stage fetuses. Horizontal sections are best suited for understanding the mediolateral relationships of muscle origins.ResultsWe confirmed a common tendinous origin of the lateral rectus (LR), inferior rectus (IR) and medial rectus (MR) muscles that was separated from the SR origin. Notably, eight fetuses (32%) had tendinous or muscular connections between the SR and other rectus muscles that had one of four morphologies: (a) a thin tendon from the SR to the common tendon of the three rectus muscles (2 fetuses), (b) a thin tendon to the LR (one fetus), (c) a thin tendon to the inferior rectus muscle origin (two fetuses), and (d) SR muscle fibers arising from an additional head of the LR (three fetuses).ConclusionsThe SR seemed to issue a thin tendon that passed along the inferior or lateral side of the oculomotor nerve. Conversely, the LR and inferior rectus muscle were likely to carry a supernumerary bundle that reached the SR. The accessory head of the medial rectus muscle showed a stable morphology in that it seemed to also provide an anomalous double head. However, the presence of an accessory head in the LR was rare. In contrast with our previously published diagram of the orbital apex, the accessory head of the medial rectus muscle passed along the lateral side of the superior oblique.

Surgical treatment for small-angle vertical strabismus

ABSTRACT To assess the indications for and results obtained with partial vertical recti muscle recession in patients with diplopia and small-angle vertical strabismus. Retrospective study of patients who underwent partial temporal or nasal recession of the superior rectus (SR) or inferior rectus (IR). Outcome was considered favorable when diplopia had resolved in primary position and downward gaze at the end of the follow-up. A total of 17 cases were included. Mean age was 69.11 years (47% women). The diagnoses were fourth nerve paresis (6), hypertropia (3), incomplete third nerve paresis (3), sagging eye (1), age-related strabismus (1), ocular myasthenia gravis (1), and restrictive strabismus after retinal surgery (2). Mean preoperative vertical deviation was 6.11 pd in primary position, and postoperative vertical deviation was 2.05 (the mean difference was statistically significant, p < 0.001). Surgery was performed on the right eye in 29.41% of patients and on the left eye in 70.58%. The SR was treated in 11 cases (temporal pole in 7 and nasal in 4) and the IR in 6 (temporal pole in 3 and nasal in 3). Mean recession was 4.14 mm ± 0.42. Outcome was favorable in 76.47% of cases at the end of the follow-up (mean, 10 months), and the previous torsion was eliminated in 5. No overcorrections were recorded. Partial SR or IR recessions were successful in most cases of small-angle vertical strabismus. There were no overcorrections in primary position gaze.

Suture loop myopexy versus silicone band loop myopexy in the management of myopic strabismus fixus

To compare two different modalities of superior rectus-lateral rectus loop myopexy; suture (SLM) and silicone band loop (SBM), in the treatment of myopic strabismus fixus. The medical records of patients with myopic strabismus fixus who underwent surgical management with either SLM or SBM at a single institution over a period of 4years were retrospectively reviewed. In cases with positive intraoperative forced duction test, the medial rectus muscle was recessed. The primary outcome measures were improvement of primary position esotropia, hypotropia, and limitations of abduction and elevation. The angle between the displaced superior rectus and lateral rectus muscles (angle of globe dislocation) was also assessed by orbital imaging before and after surgery. A total of 21 patients were identified, of whom 10 underwent SLM and 11 underwent SBM. Mean age at surgery was 65.4±5.7years in the SLM group and 68.5±6.4years in the SBM group. Both procedures significantly improved esotropia, hypotropia, angle of globe dislocation, and limitation of abduction and elevation (P<0.0001), with no significant statistical difference between procedures (P>0.05). Intraoperative muscle splitting occurred in 2 cases in the SLM group, and transient foreign body sensation was documented in 3 cases in the SBM group. In this study cohort, both techniques achieved significant correction of ocular deviation, limitation of ocular ductions, and angle of globe dislocation associated with myopic strabismus fixus, with no statistically significant difference between procedures. Operative complications in both groups were mild and innocuous.

Muscle belly union surgery with or without medial rectus recession for the treatment of high myopic strabismus fixus

To evaluate the results of surgery involving the union of the superior rectus muscle and the lateral rectus muscle with or without medial rectus recession (MRc) for the treatment of high myopic strabismus fixus over a 20-year period. The medical records of patients who underwent muscle belly union for the treatment of high myopic strabismus fixus were reviewed retrospectively. Patients were classified according to the timing of MRc. In group 1, MRc was performed before muscle union surgery; in group 2, MRc was performed concurrent with muscle union surgery; in group 3, MRc was not performed; in group 4, MRc was performed after muscle union surgery. A total of 50 eyes of 40 patients were included. Mean esotropia decreased from 57.27Δ ± 25.45Δ (range, 8Δ-100Δ) before surgery to 11.67Δ±13.85Δ (range, -18Δ to 45Δ) after (P<0.001); mean hypotropia, from 6.05Δ±9.13Δ (range, 0Δ-13Δ) before to 1.20Δ±3.03Δ (range, 0Δ-10Δ) after (P<0.001). Mean abduction improved from -2.82±1.17 (range, -4 to 0) before to -0.75±0.92 (range, -3 to 0) after (P<0.001); mean elevation, from -1.62±1.62 (range, -4 to 0) before to -0.57±0.90 (range, -3 to 0) after (P<0.001). Preoperative esotropia and postoperative limitation in abduction were significantly lower in group 3 (P=0.03; P=0.01). Muscle union surgery successfully corrected the restrictive esotropia and hypotropia. MRc in addition to muscle union surgery was not necessary for some patients, for whom preoperative esotropia was lower.

Incidence of symptomatic vertical and torsional diplopia after superior rectus transposition for esotropic Duane syndrome and abducens nerve palsy

To report the incidence of symptomatic vertical and torsional diplopia after superior rectus transposition (SRT) for esotropic Duane syndrome and abducens nerve palsy. The medical records of patients with esotropic Duane syndrome or abducens nerve palsy seen at Boston Children's Hospital (2006-2018) and treated with unilateral SRT with or without augmentation was performed. The primary outcome was incidence of postoperative vertical or torsional diplopia in primary position. The secondary outcome was induced vertical deviation in affected side gaze. A total of 69 patients met inclusion criteria: 32 with abducens nerve palsy and 37 with esotropic Duane syndrome. Vertical alignment changed in both hyper- and hypotropic directions. Median pre- and postoperative vertical deviation in primary gaze was 1.1Δ (10th-90th percentile, 0Δ-6Δ hypertropia) and 0.4Δ (10th-90th percentile, 6Δ hypotropia to 8 Δ hypertropia), respectively. Postoperative vertical diplopia occurred in 7%, including 4 of 49 treated with loop myopexy (8%), 1 of 13 without augmentation (8%), and 0 of 7 treated with sclera-fixated augmentation. All but one was successfully treated with prism or secondary surgery. Intorsional change predominated, but no patient had torsional diplopia post adjustment. Vertical misalignment in affected side gaze increased from 19% to 45% after SRT (P=0.01). In this largest-to-date review of patients treated with SRT, with or without MR recession, no patient developed persistent torsional diplopia, while 7% developed symptomatic vertical diplopia in primary position, similar to the reported incidence after balanced vertical rectus transposition. Vertical misalignment in affected side gaze increased, however fusion is already limited by unresolved esotropia in this field.

Hyperthyroidism associated with intraocular pressure and dry eye

Graves’ orbitopathy/ophthalmopathy (GO) also known as thyroid eye disease (TED),dysthyroid/thyroid-associated ophthalmopathy (TAO), is an autoimmune disorder representing thecommonest and most important extrathyroidal manifestation of Graves’ disease. Materials andMethods: This is a prospective study conducted for 2 years. A total of 60 established cases ofHyperthyroidism of all Age groups with either gender subjects who were diagnosed with Thyroidorbitopathy at hospitals were included in this study. History of ocular surgery or medications, thosedemonstrating the recent use of contact lenses, pregnant or lactating women. All the cases withsimilar presentation not proved to be Thyroid Orbitopathy and patients who did not report for thefollow-up were excluded from the study. Result: A total of 60 patients were examined. Of the 60cases analyzed, female preponderance was noted and 41-60 years age group had the highestincidence of thyroid orbitopathy. The most common presentation was found to be unilateral. Inferiorrectus muscle was the commonest muscle involved with 48.3% followed by Medial rectus muscle38.3%, Superior rectus muscle 23.3%, and Lateral rectus muscle involved least with 11.6% indescending order. None of the patients reported a loss of vision. Conclusions: Dry eye andincreased IOP have commonly seen outcomes that should be managed diligently. This potentialsight-threatening condition is seen worldwide and has many functional and cosmetic consequencesthat need to be recognized. Hyperthyroidism was significantly associated with the severity.

Adjustable graded augmentation of superior rectus transposition for treatment of abducens nerve palsy and Duane syndrome

To report the results of adjustable graded augmentation of superior rectus transposition, a novel modification of superior rectus transposition (SRT) designed to reduce postoperative vertical or torsional diplopia. The medical records of patients who underwent adjustable graded augmentation of SRT with or without adjustable medial rectus recession (MRc) from February 2017 to December 2019 were reviewed retrospectively. A Mendez ring was used to monitor torsional change after transposition of the superior rectus muscle to the lateral rectus muscle and after sequential placement of 2 or 3 augmentation sutures by superior rectus-lateral rectus loop myopexy. If excessive mechanical intorsion was induced, the responsible augmentation suture was severed intraoperatively. If torsional or vertical diplopia was noted after recovery, the distal-most augmentation suture was cut. Exotropia was managed by severing the distal-most augmentation suture or by medial rectus adjustment. A total of 8 patients who underwent adjustable graded augmentation of SRT were included (6 using the 3-suture technique): 3 for esotropic Duane syndrome, 2 for abducens nerve palsy, 1 for Moebius syndrome, and 2 for combined trochlear and abducens nerve palsies. Of the 8 patients, 4 had prior strabismus surgery, and 1 patient had previously undergone treatment with botulinum toxin. Severing one augmentation suture in 3 cases resolved vertical (n=2) or torsional (n=1) diplopia and consecutive exotropia (n=2), resulting in excellent alignment and reduction of torticollis to ≤4° in 7 cases. The technique proved insufficient in 1 patient, who had undergone 3 prior strabismus procedures. In this study cohort, adjustable graded augmentation of SRT effectively managed the risk of postoperative vertical or torsional diplopia.

Minor salivary gland transplantation for severe dry eye disease due to cicatrising conjunctivitis: multicentre long-term outcomes of a modified technique

AimTo report the clinical outcomes of autologous minor salivary gland transplantation (MSGT) for the treatment of severe dry eye disease caused by cicatrising conjunctivitis.MethodsThis was a retrospective case series of...

Ocular myocysticercosis: Atypical presentation with unilateral blepharoptosis

Cysticercosis is a parasitic infection caused by Cysticercus cellulosae, the larval form of cestode, Taenia solium. It is a preventable cause of blindness endemic in many developing countries especially where there is poor hygiene and sanitation. Humans become infected by ingestion of contaminated food and water. The most preferred locations are central nervous system (CNS), eyes, heart, bladder, muscles and subcutaneous tissues. Ocular cysticercosis can be extraocular or intraocular and may show different clinical presentations. We report a case of ocular cysticercosis which presented with unilateral ptosis and mild pain. A young male patient presented with mild swelling and drooping of right upper eyelid for 2 weeks associated with mild pain and redness on first 3 days. Ocular examination revealed ptosis and mild swelling on temporal side of right upper eyelid. The swelling was soft in consistency with no tenderness. Levator function was good with normal Bell’s phenomenon and ocular motility was in full in all cardinal gazes. The computed tomography imaging of the orbit showed bulky right superior rectus muscle with ring enhancing hypodense lesion suggestive of right eye myocysticercosis involving superior rectus muscle. The patient was treated with oral albendazole and oral prednisolone for 4 weeks and a significant improvement of ptosis was seen at 1 month follow up visit. Extraocular muscle cysticercosis should be highly suspicious in young patients with unilateral acquired blepharoptosis. Radiological investigations play a vital role in diagnosis and a complete resolution can be achieved with standard medical therapy alone.

Functional Anatomy of Muscle Mechanisms: Compensating Vertical Heterophoria

Magnetic resonance imaging (MRI) of extraocular muscle function was used to evaluate the role of newly recognized mechanisms underlying compensation of large heterophoria by vertical fusional vergence (VFV). Prospective case series. At one academic center, 8 adults with large hyperphoria and supernormal VFV underwent MRI during monocular and binocular fixation of a centered, near target. Contractility of the rectus and superior oblique (SO) extraocular muscles in hypertropic and hypotropic eyes was determined from changes in posterior partial volume (PPV). Five of 8 patients could sustain binocular fusion in the scanner. In those patients, VFV corrected approximately 5-degree misalignment, approximately 5-fold greater than normal VFV. Vertical strabismus was compensated mainly by significant contractility of the lateral more than the medial compartment of the inferior rectus (IR) in both eyes (P < .005). The superior rectus (SR) and inferior oblique muscles had no significant contractile contribution, although the hypotropic SO relaxed significantly. The IR lateral compartment and SR medial compartment significantly co-relaxed when binocular fusion was attained from monocular target fixation (P < .01). Although VFV protects patients from small muscle imbalances over the lifespan, even enhanced VFV may be inadequate to avert diplopia. Compensation of hyperphoria by VFV is accomplished mainly by IR muscle relaxation in the hypotropic eye, principally in its selectively innervated lateral compartment, whereas the SO contributes little. Fusion involves compartmentally selective co-relaxation in hypotropic eye vertical rectus muscles. Taken together, these overall findings suggest a physiologic basis to prefer therapeutic surgical weakening of the medial IR in the hypotropic eye.

Radiographic analysis of fatty infiltration of the extraocular muscles in thyroid eye disease

ABSTRACT Purpose Fatty infiltration of the extraocular muscles has been described radiographically in patients with thyroid eye disease (TED), yet it has not been studied on a large scale nor quantified. Our purpose was to define and characterize this entity in patients with TED. Methods An IRB-approved cross-sectional retrospective review of medical records identified patients with a clinical diagnosis of TED and at least one CT of the orbits. A 2:1 age and sex-matched control population consisted of patients without a history nor radiographic evidence of orbital disease or systemic thyroid abnormality. The presence of fatty infiltration in each extraocular rectus muscle was defined using Hounsfield units (HU). Laterality, muscles involved, and pattern of fatty infiltration were also evaluated. Student’s t-tests, Chi-square, and Fisher’s exact tests were used to compare TED and control groups. Results The study population consisted of 252 patients with TED and 504 age and sex-matched controls. Fatty infiltration was significantly more prevalent in TED patients (36/252, 14.3%) compared to controls (11/504, 2.2%) (p < .001). The mean density of fat infiltration was significantly lower in TED patients (−40.4 HU) than controls (−34.8 HU) (p = .048). In TED patients, the frequency of muscle involvement was inferior rectus (61.8%), lateral rectus (19.7%), superior rectus (11.8%) and medial rectus (6.6%), which was not significantly different than controls (p > .05). Most muscles (88.2%) in the TED group exhibited a heterogeneous pattern of infiltration, which did not differ from controls (p = .34). Conclusions This study characterizes fatty infiltration of the extraocular muscles in patients with TED.