Medial Rectus Research Articles

Orbital Myositis and Strabismus: Clinical Profile, Management, and Predictive Factors for Recurrence.

To study the clinical profile of patients with orbital myositis and their management modalities and predictive factors for recurrence. The records of all consecutive patients diagnosed as having orbital myositis from 2010 to 2022 were reviewed. Patient demographics, presenting complaints, visual function, primary gaze deviation, and extraocular muscle involved were studied in the clinical profile. The radiological modalities and their management along with the recovery status and need for surgical intervention were documented. Fifty-two patients (55 eyes) (69% women) were diagnosed as having orbital myositis with a mean age of 36 ± 16 years presenting with periocular pain (55%) followed by diplopia (49%). Disease was unilateral in 94%. Sixty percent had ocular misalignment in primary gaze. The medial rectus was the most involved muscle (58%), with abduction limitation in 73%. Computed tomography (42%), magnetic resonance imaging (42%), and combined imaging (16%) were used in localizing the disease. Muscle biopsy was done in 38% of patients. Systemic immunomodulators were required in 16%. Strabismus surgery was planned in 15% of patients and done in 11%. Recurrence was noted in 43%. Abrupt cessation of steroids was a significant risk factor in recurrence of the disease (P = .046). Recovery was partial in 44% of patients and complete in 47%. Systemic steroids with slow taper has satisfactory outcomes in orbital myositis. Patients refractory to treatment ideally should undergo biopsy and begin taking steroid-sparing agents. Once the disease is in remission, residual disease can be surgically treated for better functional outcome. [J Pediatr Ophthalmol Strabismus. 20XX;X(X):XXX-XXX.].

Evaluation of the Differences in Parameters Obtained from the Computed Tomography Images of the Eyeball and the Structures in the Orbit by Age and Gender

Objective: The aim of this study is to show the variation of eyeball and orbital structures according to different age groups and gender. Methods: The study was carried out on 4 age groups over 30-40, 41-50, 51-60, 61. The parameters were, the angle between the optic nerve and axis of eyeball (A-Cr2AA), the length of the medial rectus muscle (MRML) and the length of the lateral rectus muscle (LRML) up to the Zinn ring, the thickness of the lens (LT),), the length of the optic nerve from the Zinn ring (Cr2L), optic nerve thickness (Cr2T), distance between two eyeballs (BOD) and the others. Results: As a result of the study, in the comparison of males in four groups, significant difference was found between the groups in LT, Cr2L, A-Cr2AA, MRML parameters in the right eyeball and Cr2L and LRML parameters in the left eyeball (p

Evaluation of the Normal Measurements of Orbital Structures in Healthy Adult Individuals by Using a Magnetic Resonance Imaging Method

Background: This study aims to determine the normal values of orbital structures according to sex in healthy adults. Methods: Diameters of extraocular muscles, the width of the optic nerve sheath diameter, the length of the inter-zygomatic line, ocular bulb length, and globe position were measured in the T1-weighed MR (magnetic resonance) images in 204 orbits of 102 individuals. Results: The mean values of the diameters of the extraocular muscles in males and females were as follows: medial rectus, 3.96 ± 0.52 and 3.58 ± 0.53 mm; lateral rectus, 3.47 ± 0.61 and 3.15 ± 0.48 mm; inferior rectus, 4.47 ± 0.53 and 4.07 ± 0.48 mm; superior rectus, 4.44 ± 0.64 and 4.01 ± 0.56 mm; and superior oblique, 3.68 ± 0.49 and 3.45 ± 0.44 mm. The length of the interzygomatic line in males and females were 102.68 ± 3.89 and 96.95 ± 3.4 mm, the ocular bulb length was 23.33 ± 1.32 and 22.83 ± 1.1 mm, the globe position was 7.66 ± 1.33 and 7.3 ± 1.39 mm, and the width of the optic nerve sheath diameter was 4.65 ± 0.62 and 4.28 ± 0.51 mm, respectively. All measurements were significantly greater for males than for females (p < 0.05). Conclusions: We believe that a practical and quantitative method will be provided by this study for the diagnosis and determination of the normative values of orbital structures.

Acute Acquired Comitant Esotropia

Acute acquired comitant esotropia (AACE) is an infrequent presentation of esotropia, characterized by sudden onset eye misalignment and diplopia. The purpose of this article is to review four cases of children diagnosed with AACE. We present 4 cases (children 610 years) of AACE. All of them suddenly developed diplopia and esotropia, with largeangle. After complete ophthalmological and neurological examinations in three cases out of four, strabismus surgery was conducted. In one case heterogenous neoplasm was detected and sent to an oncologist and neurosurgeon for evaluation and morphological verification. Bilateral medial rectus recession in two cases and unilateral recession of the medial rectus and resection of the lateral rectus in one case were performed. After strabismus surgery fully recovered binocular vision and was no longer noticeable diplopia. Neurological examinations and neuroimaging should be performed to exclude any potential intracranial disease. Surgery should be taken into consideration 6 months after the onset of the esotropia, if the deviation is stable. Strabismus surgery of AACE has good motor and sensory results and can successfully restore good binocular function The excessive use of smartphones may be associated with developing and increasing AACE.

The Use of Botulinum Toxin to Treat Infantile Esotropia

Injection of botulinum toxin type A into both rectus muscles is an alternative to surgery and has given good results in children with infantile esotropia. Reducing the angle of deviation can help restore binocular vision, which in turn will promote motor fusion and allow better control of the strabismus and may even lead to eventual healing. We report the result after 6 months of injection of botulinum toxin in the medial rectus in 6 children with infantile esotropia.

Medial rectus re-advancement: more bang for your buck?

ABSTRACT Introduction: Although there are guidance tables in the literature on surgical dosage for primary medial rectus resection-lateral rectus recession surgery, there is a lack of consensus on the surgical gains in medial rectus re-advancement (MRR) for the management of consecutive exotropia. We compared the surgical outcomes of primary medial rectus resection-lateral recession (RR) surgery, to MRR in patients with consecutive exotropia. Methods: Retrospective, electronic note review of consecutive patients undergoing primary RR surgery for basic exotropia (RR group), convergence insufficiency-type exotropia, and divergence excess, and consecutive patients undergoing MRR with or without lateral rectus recession (MRR group) for consecutive exotropia in a teaching university hospital. Results: There were 84 patients in the RR group and 27 patients in the MRR group. The median age in the RR group was 25.50 years (range 4–79) and 45 years (18–87) in the MRR group (p = .002). Median follow-up was 7 months (3–43) in the RR group and 1 month (1–12) in the MRR group. Post-operatively, there was a median exotropia reduction of 27.00 prism diopters (PD) (range +5, –65; p < .0001) for near, and 27.00 PD (+10, –51; p < .0001) for distance in the RR group. In the MRR group, the median exotropia reduction was 34.50 PD (2, –67; p < .0001) for near and 33.00 PD (1, –67; p < .0001) for distance. There was a greater reduction in the exotropia in the MRR group compared to the RR group for distance (p = .047), but this did not meet statistical significance for near (p = 0.10). The median dose–effect relationship (PD/millimeter) was higher in the MRR group both for near deviation (2.90 vs 2.15, p = .0073) and for distance deviation (2.91 vs 2.15, =0.0041). Conclusion: Based on our study cohort, medial rectus re-advancement appears to have a greater dose-effect in reducing the distance angle of deviation for both near and distance compared to primary recess-resect surgery. Further prospective longitudinal studies would shed further light on the dose–effect relationship over time.

Inferior Rectus Muscle Thermal Injury Following Transconjunctival Blepharoplasty Using Carbon Dioxide Laser.

A 56-year-old woman was referred to the authors' hospital after the removal of the lower eyelid fat through a transconjunctival approach using a carbon dioxide laser. The patient was noted to have vertical diplopia in the primary position, with worsening diplopia on downgaze. Detachment of the right inferior rectus (IR) muscle from its insertion point was observed during exploratory surgery. The thermally damaged IR muscle fibers were attached to a location posterior to the original insertion point. At 6 months postoperatively, 8 prism diopters of right hypertropia in the primary position and a -3 degrees limitation on downgaze were still present. The patient underwent the vertical transposition of the lateral and medial rectus muscles to the IR muscle. After strabismus surgery, orthotropia was observed with no vertical diplopia in the primary gaze, but ocular motility limitation on the downgaze has permanently remained.

Prospective Comparison of FOCUS MUSE and Single-Shot Echo-Planar Imaging for Diffusion-Weighted Imaging in Evaluating Thyroid-Associated Ophthalmopathy.

To prospectively compare single-shot (SS) echo-planar imaging (EPI) and field-of-view optimized and constrained undistorted single-shot multiplexed sensitivity-encoding (FOCUS MUSE) for diffusion-weighted imaging (DWI) in evaluating thyroid-associated ophthalmopathy (TAO). SS EPI and FOCUS MUSE DWIs were obtained from 39 patients with TAO (18 male; mean ± standard deviation: 48.3 ± 13.3 years) and 26 healthy controls (9 male; mean ± standard deviation: 43.0 ± 18.5 years). Two radiologists scored the visual image quality using a 4-point Likert scale. The image quality score, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC) of extraocular muscles (EOMs) were compared between the two DWIs. Differences in the ADC of EOMs were also evaluated. The performance of discriminating active from inactive TAO was assessed using receiver operating characteristic curves. The correlation between ADC and clinical activity score (CAS) was analyzed using Spearman correlation. Compared with SS EPI DWI, FOCUS MUSE DWI demonstrated significantly higher image quality scores (P < 0.001), a higher SNR and CNR on the lateral rectus muscle (LRM) and medial rectus muscle (MRM) (P < 0.05), and a non-significant difference in the ADC of the LRM and MRM. Active TAO showed higher ADC than inactive TAO and healthy controls with both SS EPI and FOCUS MUSE DWIs (P < 0.001). Inactive TAO and healthy controls did not show a significant ADC difference with both DWIs. Compared with SS EPI DWI, FOCUS MUSE DWI demonstrated better discrimination of active from inactive TAO (AUC: 0.925 vs. 0.779; P = 0.007). The ADC was significantly correlated with CAS in SS EPI DWI (r = 0.391, P < 0.001) and FOCUS MUSE DWI (r = 0.645, P < 0.001). FOCUS MUSE DWI provides better images for evaluating EOMs and better performance in diagnosing active TAO than SS EPI DWI. The application of FOCUS MUSE will facilitate the DWI evaluation of TAO.

Efficacy of Nasal Septal Complex in the Endoscopic Reconstruction of Medial Orbital Wall.

The aim of this study is to investigate the efficacy of nasal septal complex reconstructing the medial orbital wall under some specific circumstances. The authors performed a study that included 10 patients who underwent isolated medial orbital wall fracture (blow-out fracture). All the reconstruction surgery of the patient included in this study fixed defect of medial orbital wall using autologous nasal septal complex (composed of nasal septal cartilage and perpendicular plate of ethmoid). The authors observed postoperative improvements of diplopia or ocular motility disorders of the affected orbit. The surgeries had gained satisfactory results, and without severe postoperative complications. After long-term follow-up, postoperative CT indicated the implant-covered defect of medial orbital wall, and there's no incarceration of the medial rectus. Meanwhile, the authors found there is no crack in the implant, and the surgery using nasal septal complex achieved premorbid orbital form. Autologous nasal septal complex provides a better complement to endoscopic reconstruction of medial orbital wall; this strategy allows nasal septum to reconstruct isolated medial orbital wall defects of various degrees, such as nasal septum fracture and dysplasia of perpendicular plate of ethmoid.

Botulinum toxin-A in acute acquired comitant esotropia during COVID pandemic in children and young adolescents

Abstract Purpose: To study the effectiveness of botulinum toxin A (BTX-A) in the treatment of patients with acute acquired comitant esotropia (AACE) due to excessive use of mobile and laptops in the COVID era in the pediatric population and adolescents. Methods: This was a retrospective, interventional study of pediatric patients and young adults who presented with AACE and received unilateral or bilateral BTX-A. All the patients complained of binocular diplopia and sudden onset of esotropia with a history of mobile or laptop usage during the COVID era (2020–2023). Twenty-seven patients with acute-onset esotropia in 3 years (2020–2023) were included. All patients were administered 2.5–7.5 units of BTX-A (Botox, Allergan, India) into the unilateral or bilateral medial rectus muscle of the deviating eye under short general anesthesia or local anesthesia. The main outcome measures were pre- and post-injection angle of deviation, pre- and post-injection stereopsis, final level of stereopsis achieved, recurrence, and whether strabismus surgery was later required. Results: The mean age of patients was 12.85 ± 7.15 years (range: 4–25 years). The mean dosage of Botox was 6 U (2.5–7.5 U). The mean follow-up was 6 months (6 months–2 years). The mean preoperative angle of deviation (AOD) was 41.11 ± 10.9 prism diopters (PD) for distance and 41.67 ± 10.9 PD for near. The maximum effect of BTX-A was seen at 1 month; post-injection AOD was 13.65 ± 14.7 PD for distance and 14.87 ± 15.8 PD for near (P &lt; 0.001). Over half of the patients achieved optimal outcomes, with improvements in stereopsis and sensory fusion. Early intervention (within 3 months of symptom onset) significantly correlated with treatment success. Conclusion: While BTX-A therapy for acute-onset esotropia demonstrates efficacy, patient-specific considerations are essential. This study highlights the evolving nature in the digital age and early administration of BTX-A along with close follow-up to monitor residual and recurrence of esotropia. The surgical intervention can increase the final success rate.

Efficacy of Fat and Perifascial Areolar Tissue Graft in Refractory Esotropia: A Case Report

Purpose: This case report presents a novel approach for the management of refractory esotropia using adhesiolysis and fat and perifascial areolar tissue (PAT) transplantation.Case summary: A 62-year-old male presented with left eye strabismus fixus following iatrogenic medial rectus (MR) muscle injury and medial orbital wall fracture during endoscopic sinus surgery. One month later, he underwent MR laceration repair and orbital wall reconstruction. Despite three subsequent interventions for exotropia and its subsequent conversion to esotropia, the left eye esodeviation progressively worsened, culminating in strabismus fixus. Initial examination revealed significant left eye esotropia with fixed gaze and 5-mm enophthalmos. Surgery included implant removal, adhesiolysis between the eyeball and surrounding tissues, scar and MR recession, and placement of a fat and PAT graft on the medial aspect of the eyeball to prevent postoperative re-adhesion. Three years of follow-up demonstrated sustained orthophoria in primary gaze with improved extraocular muscle function and enophthalmos.Conclusions: Fat and PAT graft has potential in oculoplastics for preventing re-adhesion and augmenting orbital volume in patients with refractory restrictive strabismus due to multiple surgeries.

Satellite cell distribution in the medial rectus muscle in cadavers

Background: This study aimed to elucidate the potential usefulness of the medial rectus muscle of cadavers for research on satellite cells.Methods: Twenty-four medial rectus muscles were obtained from 12 cadavers. The control group included six medial rectus muscles from three live adults without brain activity. The muscle fiber diameter and distribution of satellite cells were measured and compared. Immunohistochemistry for myosin heavy chain and the transcription factor PAX7 was performed, and the distributions of myocytes and satellite cells were evaluated.Results: The average muscle fiber diameter was 142.18±36.49 μm in the cadaver group and 149.34±15.26 μm in the control group, and there was no significant difference between the two groups (p=0.38). The ratio of PAX7(+) cells to the number of muscle fibers was 0.056±0.015 in the control group and 0.006±0.006 in the cadaver group, reflecting a significant difference (p&lt;0.05).Conclusions: The medial rectus muscles of cadavers can be helpful in studying anatomical morphology; however, their usefulness in muscle satellite cell research appears to be limited.

Agreement between intraoperative and anterior segment optical coherence tomography measurements of the extraocular muscle insertion distance in patients with previous strabismus surgery

PurposeTo evaluate the agreement between anterior segment optical coherence tomography (AS-OCT) measurement of preoperative distance from the limbus to the horizontal rectus muscles insertion and intraoperative measurement in patients who have previously undergone strabismus surgery and required reoperation. MethodsSubjects from two ophthalmological centers were included. Preoperative AS-OCT was used to measure the muscle insertion from the limbus, and intraoperative measurements were obtained using calipers. Interclass correlation coefficient and Bland-Altman agreement analysis were used. ResultsA total of 53 horizontal rectus muscles from 24 patients with previous strabismus surgery were analyzed: 27 medial rectus (MR) and 26 lateral rectus (LR) muscles, including both previously operated and previously unoperated muscles. Average AS-OCT measurements of MR was 8.54 ± 2.42 mm and intraoperatively was 9.4 ± 3.09 mm. Average AS-OCT for LR was 8.32 ± 2.25 mm and intraoperatively was 9.34 ± 3.73 mm. 63% of MR muscles and 77% of LR muscles were within 1 mm between AS-OCT and intraoperative measurement. Spearman’s correlation coefficient showed positive correlation between measures for both MR and LR muscles. The interclass correlation coefficient was 0.79 (95% CI, 0.56-0.90) for MR muscles and 0.70 (95% CI, 0.44-0.85) for LR muscles, with a good agreement. Agreement was better for muscles ≤10 mm from the limbus (which included both previously operated and unoperated muscles) than for muscles found >10 mm from the limbus. ConclusionsGood agreement was observed between the measurement of limbus-insertion distance obtained by AS-OCT and by intraoperative measurement, especially when the muscle insertion was ≤10 mm from the limbus.

Medial rectus insertion site in cases of acute acquired comitant esotropia associated with excessive digital device usage.

To compare the distance of the medial rectus muscle insertion to the limbus (DMIL) between patients with acute acquired comitant esotropia (AACE) associated with excessive digital device usage (EDDU) and exotropic patients. Retrospective study. The medical records of 72 eyes of 44 patients with EDDU were retrospectively analyzed. The DMIL was measured from the anterior part at the midpoint of the medial rectus muscle insertion into the anterior limbus using a caliper after dissecting the medial rectus muscle with two control sutures at 12 o'clock and 6 o'clock. The DMIL in the non-fixation eye was compared between 44 patients with AACE and 23 patients with exotropia. The mean daily EDDU was 6.5 ± 3.1h. The mean cycloplegic refractive errors (spherical equivalent: SE) were - 3.18 ± 2.52 diopters (D) OD and - 3.03 ± 2.42 D OS. The mean DMIL in the 72 eyes of 44 patients with AACE associated with EDDU was 4.30 ± 0.66mm. The difference in DMIL of non-fixation eyes between 44 AACE patients and 23 exotropic patients was significant (4.28 ± 0.65mm vs. 5.28 ± 0.50mm, p < 0.0001). However, the SE in 44 non-dominant eyes of AACE was - 3.08 ± 2.56 D, significantly stronger than - 1.22 ± 1.93 D in the 23 exotropic eyes (p = 0.008). DMIL in patients with AACE associated with EDDU was significantly shorter. This anatomical anomaly may be an etiology of AACE associated with EDDU.

Microcephaly with or without chorioretinopathy, lymphedema, or mental retardation (MCLMR)- the new lacunae: a case report

BackgroundMicrocephaly with or without chorioretinopathy, lymphedema, or mental retardation is a rare autosomal dominant disease caused by mutations in KIF11 which disrupt EG5 protein function, impacting the development and maintenance of retinal and lymphatic structures due to its expression in the retinal photoreceptor cilia. The primary ocular finding in MCLMR is chorioretinopathy. Additional features can include microphthalmia, angle-closure glaucoma, persistent hyperplastic primary vitreous, cataract, pseudo-coloboma, persistent hyaloid artery, and myopic or hypermetropic astigmatism. The appearance of the chorioretinal lesions as white to pinkish, round, non-elevated atrophic areas devoid of blood vessels resembles the lacunae in Aicardy syndrome. Due to the lack of systematic description of the lesions and significant phenotypical variability, there is an impending need for a detailed report of each case.Case presentationA child with microcephaly detected in the third trimester of gestation began her following in the ophthalmology department due to a non-visually significant cataract. Shortly after, she developed nystagmus and large-angle alternating esotropia with cross-fixation. Her fundus initially showed a pallid optic disc and pigmentary changes, developing thereafter retinal lacunae and a retinal fold. Her differential diagnosis accompanied the dynamic changes in her fundus, which included congenital infections, Leber´s Congenital Amaurosis and Aicardy syndrome. At 19 months old, genetic testing identified a heterozygous mutation (c.1159 C > T, p.Arg387*) in the KIF11 gene. The patient underwent bilateral medial rectus muscle recession surgery at 2 years old for persistent esotropia, with significant improvement. Refraction revealed a hyperopic astigmatism in both eyes (+ 0.25 -2.50 × 180 OD and + 0.75 -2.00 × 170 OS). She continues to require right eye patching for 2 hours daily.ConclusionsThis case report expands the phenotypic spectrum of MCLMR by demonstrating a unique combination of retinal features which sheds new light on differential diagnosis from Aicardy syndrome. Our findings emphasize the significant phenotypic variability associated with MCLMR, particularly regarding ocular involvement. This underscores the importance of detailed clinical evaluation and comprehensive reporting of cases to improve our understanding of the disease spectrum and genotype-phenotype correlations.

Detailed measurements of the four extraocular rectus muscles’ contribution to the perfusion of the anterior segment of the eye

Background/aimsAnterior segment ischaemia (ASI) is a rare but serious complication of strabismus surgery, which may be caused by damage to the anterior ciliary arteries that run along the rectus muscles....

Orbital Involvement as an Initial Presentation of Sinonasal Neuroendocrine Carcinoma

Purpose: To present a case of sinonasal neuroendocrine cancer initially manifesting with orbital involvement.Case summary: A 63-year-old female patient visited a neuro-ophthalmologic clinic due to a 3-week history of decreased visual acuity (VA), color vision abnormalities, and swelling of the upper eyelid in right eye. Best-corrected VA (BCVA) in the right eye was 0.8. Clinical findings included a relative afferent pupillary defect, restricted eye movement in lateral, superior, and medial gaze, and exophthalmos in the right eye. Wide-field fundus photography and optical coherence tomography indicated swelling of right optic disc. Magnetic resonance imaging was performed revealing a mass invading nasal cavity, sinus, and right orbital apex, and compressing the medial rectus, inferior rectus, superior oblique, and optic nerve. An otolaryngological nasal biopsy was conducted and immunohistochemical staining showed positive results for Ki-67, NSE, p16, P-53, and CD56, leading to a diagnosis of small cell neuroendocrine carcinoma with an irreducible tumor stage. Prior to initiation of treatment (concurrent chemoradiotherapy, CCRT), there was rapid worsening of VA and eye movement in the right eye. CCRT commenced alongside high-dose steroid treatment. One month following treatment, the BCVA of the right eye improved and protrusion of the right eye resolved. Six months after starting CCRT, a contrast-enhanced orbital computed tomography scan showed no residual lesion. The BCVA of the right eye stabilized at 0.3 with complete recovery of color vision and eye movement.Conclusions: Neuroendocrine cancer should be considered as a possible diagnosis in cases of rapidly progressing compressive optic neuropathy.

Botulinum toxin A as a treatment modality for acute acquired comitant esotropia - An Indian perspective.

To analyze the outcomes of botulinum toxin A injection in acute acquired comitant esotropia (AACE). This is a retrospective study that included cases diagnosed as AACE between January 2022 and February 2023. Patients who were treated with Botox and completed a minimum 3 months follow-up were included in the study. All the patients underwent a complete ophthalmic, orthoptic examination and neuroimaging. The effects of age, onset of esotropia, screen time, deviation pre injection, mode of injection ( transconjunctival/ open sky) and whether injection was administered in one/both eyes on successful outcome were analysed. Twenty-seven patients (20 male, seven female) were included in the study. The median age was 10 years. The median deviation for distance and near preinjection was 35 and 40 prism diopters, respectively. Complete resolution of symptoms was noted in 18 patients (66.6%). Four patients needed prisms, two required repeat injections, and one each needed surgery and divergence therapy. Six patients developed ptosis. None of the risk factors seemed to affect outcomes. Botulinum toxin injected into the medial rectus is a safe and viable option for AACE. Preinjection counseling about ptosis, recurrence needing prisms, reinjection, or surgery is important.

Subclinical Ocular Motility Dysfunction and Extraocular Muscle Changes in Inactive Graves' Orbitopathy.

This study aimed to investigate the presence of structural and functional changes in extraocular muscles (EMs) among patients with inactive Graves' orbitopathy (GO) classified according to the Clinical Activity Score (CAS). Sixty-seven patients with Graves' disease (GD) and inactive GO were included. The data collected included clinical parameters, thyroid function, autoantibody levels, EOM morphology via orbital ultrasound (US), and ocular motility. Patients were stratified into Red Filter Test (RFT)-positive or RFT-negative groups based on the presence or absence of latent diplopia during the RFT examination. Thirty-three patients (49.25%) exhibited latent diplopia on the RFT, despite not reporting double vision during standard ocular motility tests. Significant differences were observed between the two groups in terms of age, disease duration, intraocular pressure (IOP) elevation in up-gaze, and medial rectus muscle thickness (p < 0.05). No significant differences were found in thyroid status, TRAb and ATA levels, CASs, exophthalmos, or lateral rectus thickness between the two groups. This study revealed that in inactive GO, subclinical EM dysfunction and morphological changes may be present, which might not be apparent through routine ocular examinations. The RFT is effective in detecting latent diplopia, highlighting its utility in identifying subtle ocular motility issues and subclinical muscle involvement. Comprehensive evaluations combining functional tests like the RFT and imaging are essential for early detection of GO-related abnormalities, enabling tailored and prompt management and improving patient outcomes.

Role of diffusion tensor imaging of extra ocular muscles and orbital fat in Graves’s ophthalmopathy and relation to disease activity

BackgroundGraves’ ophthalmopathy (GO) is one of the most common autoimmune inflammatory disorders affecting the orbit that characterized by swelling of extra ocular muscles (EOMs) and expansion of the orbital fat. Diffusion tensor imaging (DTI) could assess the microstructural integrity of tissue. We aimed at this study to assess the role of DTI in the evaluation of EOMs and orbital fat in GO and identify the relationship with disease activity.ResultsCase–control study included 40 patients diagnosed as Graves’ disease (20 active and 20 inactive) and 10 health control subjects underwent DTI. Low fraction anisotropy (FA) and high mean diffusivity (MD) of inferior rectus (IR), medial rectus (MR) and orbital fat in GO versus healthy control (HC), while high FA and high MD in active group versus inactive group. In order to differentiate between GO and HC; FA cutoff point of IR, MR& orbital fat were 0.46, 0.45 and 0.26 with sensitivity 98.8%,98.8% and 93.8% and specificity 95.0%, 95.0% and 85%, respectively. MD cutoff point for IR, MR and orbital fat 1.24, 1.27 and 1.275 with sensitivity 97.5%, 98.8% and 98.8% and specificity 95.0%, 95% and 95%, respectively. To differentiate between active and inactive GO; FA cutoff point of IR, MR and orbital fat were 0.35, 0.36 and 0.22 respectively with sensitivity 80.0%, 82.5% and 72.5% and specificity 95.0%, 85.0% and 65.0%, respectively. MD cutoff point for IR, MR and orbital fat were 1.58, 1.63 and 1.54 respectively with sensitivity 90.0%, 97.5% and 85.0%, and specificity 90.0%, 80.0% and 62.5%, respectively.ConclusionsDTI parameters (FA and MD) of EOMs and orbital fat are considered as crucial radiological biomarkers for diagnosis of GO and could quantitatively differentiate active form inactive disease.