Extraocular Muscles Research Articles

Developmental, Physiological and Phylogenetic Perspectives on the Expression and Regulation of Myosin Heavy Chains in Craniofacial Muscles.

This review deals with the developmental origins of extraocular, jaw and laryngeal muscles, the expression, regulation and functional significance of sarcomeric myosin heavy chains (MyHCs) that they express and changes in MyHC expression during phylogeny. Myogenic progenitors from the mesoderm in the prechordal plate and branchial arches specify craniofacial muscle allotypes with different repertoires for MyHC expression. To cope with very complex eye movements, extraocular muscles (EOMs) express 11 MyHCs, ranging from the superfast extraocular MyHC to the slowest, non-muscle MyHC IIB (nmMyH IIB). They have distinct global and orbital layers, singly- and multiply-innervated fibres, longitudinal MyHC variations, and palisade endings that mediate axon reflexes. Jaw-closing muscles express the high-force masticatory MyHC and cardiac or limb MyHCs depending on the appropriateness for the acquisition and mastication of food. Laryngeal muscles express extraocular and limb muscle MyHCs but shift toward expressing slower MyHCs in large animals. During postnatal development, MyHC expression of craniofacial muscles is subject to neural and hormonal modulation. The primary and secondary myotubes of developing EOMs are postulated to induce, via different retrogradely transported neurotrophins, the rich diversity of neural impulse patterns that regulate the specific MyHCs that they express. Thyroid hormone shifts MyHC 2A toward 2B in jaw muscles, laryngeal muscles and possibly extraocular muscles. This review highlights the fact that the pattern of myosin expression in mammalian craniofacial muscles is principally influenced by the complex interplay of cell lineages, neural impulse patterns, thyroid and other hormones, functional demands and body mass. In these respects, craniofacial muscles are similar to limb muscles, but they differ radically in the types of cell lineage and the nature of their functional demands.

Efficacy of tocilizumab in patients with moderate-to-severe corticosteroid-resistant thyroid eye disease: a prospective study.

To evaluate the clinical outcomes of intravenous tocilizumab (TCZ) injection in patients with moderate-to-severe active thyroid eye disease (TED). Patients with active and moderate-to-severe TED who did not respond to conventional therapies were treated with TCZ from June 2019 to January 2021. The medical records of the patients were evaluated before the treatment. We analyzed patient demographics, including the duration of Graves' disease and TED, and assessed subjective symptoms, such as diplopia and ocular movement, clinical activity score (CAS), modified NOSPECS score, and exophthalmos before treatment and at 4, 8, 12, and 16weeks after the first drug injection. Blood tests, including TSH Rc Ab and TS Ab, were performed before treatment and 24weeks after the first injection. And orbital computed tomography (CT) was performed and Barrett's Index was calculated at baseline and after completion of all injections. Nineteen completed the scheduled treatment. There were no significant side effects, other than herpes zoster in one case and headache and dermatitis in another. Clinical symptoms before and 16 weeks after the treatment showed mean CAS decreased by 2.4 points, mean modified NOSPECS score decreased by 3.7 points, and mean exophthalmos decreased by 0.4 mm. Diplopia and extraocular muscle limitation improved in ten and remained stationary in five of the 15 patients, who presented with extraocular motility abnormalities. Six of 11 patients who underwent orbit CT showed improvement in muscle size. The mean TSH Rc Ab decreased by 7.5 IU/L and TS-Ab decreased by 162.9%. TCZ can treat active moderate-to-severe TED, showing high drug compliance and reasonable response to inflammation and extraocular motility abnormality.

Unilateral Internuclear Ophthalmoplegia in a 14-year-old Female

Purpose: Internuclear ophthalmoplegia (INO) is an eye movement disorder caused by a lesion of the medial longitudinal fasciculus. It typically manifests bilaterally and is commonly caused by multiple sclerosis. We report a case of pediatric unilateral INO, which is rare in the pediatric population.Case summary: A 14-year-old female, with a history of traumatic head injury 9 days previously, presented with diplopia, nausea and vomiting for the past 5 days. Her ophthalmic examination revealed severely impaired adduction of the right eye and abduction nystagmus in the left eye. Orbital computed tomography showed no evidence of orbital wall fracture or muscle impingement. However, an magnetic resonance imaging of her brain demonstrated an infarct in the right paramedian midbrain, leading to a diagnosis of unilateral INO. Diplopia and impaired adduction of the right eye resolved completely 7 weeks after the trauma.Conclusions: Demyelinating diseases, such as multiple sclerosis, account for most of the pediatric INO cases. Although most of these cases are bilateral, this reports highlights a pediatric case of unilateral INO following head injury, which is an uncommon occurrence in this age group.

Correlation between extraocular muscle enlargement and thyroid autoantibodies in thyroid eye disease

PurposeThis study aimed to investigate the factors affecting extraocular muscle enlargement in thyroid eye disease (TED).Study designRetrospective study.MethodsThe thyroid-stimulating hormone (TSH) receptor antibody (TRAb), thyroid-stimulating antibody (TSAb), antithyroid peroxidase antibody (ATPO), and antithyroglobulin antibody (ATG) levels in patients diagnosed with TED who underwent orbital magnetic resonance imaging were assessed. The control group comprised the contralateral eye of patients who underwent orbital magnetic resonance imaging (MRI) for unilateral eyelid tumors or orbital disease. The thickness of the bilateral rectus muscles and superior oblique muscles was measured on orbital MRI. Muscle enlargement was classified as unilateral/bilateral and symmetric/asymmetric. The effects of age, sex, smoking history, TSH, thyroid hormone, and thyroid autoantibodies on the muscle thickness and number of enlarged muscles were assessed by use of simple and multiple regression analyses.ResultsThe TED and control groups comprised 41 and 44 cases, respectively. The positivity rate of TSAb in patients with TED was 92.7% higher than that of the other autoantibodies. Muscle enlargement was observed in 29 of the 41 cases (70.7%). Older age and higher TSAb levels were identified as significant factors affecting the total muscle thickness and number of enlarged muscles. Bilateral muscle enlargement and asymmetrical muscle enlargement were observed in 17 (58.6%) and 23 (79.3%) of the 29 cases, respectively. The TSAb levels and age had no significant effect on the type of muscle enlargement.ConclusionsTSAb showed significant associations with extraocular muscle enlargement. Measurement of TSAb, rather than of TRAb, may be more useful for diagnosing extraocular muscle enlargement in patients with TED.

Extrinsic Laryngeal Muscle Activity With Different Diameters and Water Depths in a Semi-Occluded Vocal Tract Exercise.

Surface electromyography (sEMG) has been used to evaluate extrinsic laryngeal muscle activity during swallowing and phonation. In the current study, sEMG amplitudes were measured from the infrahyoid and suprahyoid muscles during phonation through a tube submerged in water. The sEMG amplitude values measured from the extrinsic laryngeal muscles and the electroglottographic contact quotient (CQ) were obtained simultaneously from 62 healthy participants (31 men, 31 women) during phonation through a tube at six different depths (2, 4, 7, 10, 15, and 20 cm) while using two tubes with different diameters (1 and 0.5 cm). With increasing depth, the sEMG amplitude for the suprahyoid muscles increased in men and women. However, sEMG amplitudes for the infrahyoid muscles increased significantly only in men. Tube diameter had a significant effect on the suprahyoid sEMG amplitudes only for men, with higher sEMG amplitudes when phonating with a 1.0-cm tube. CQ values increased with submerged depth for both men and women. Tube diameter affected results such than CQ values were higher for men when using the wider tube and for women with the narrower tube. Vocal fold vibratory patterns changed with the depth of tube submersion in water for both men and women, but the patterns of muscle activation differed between the sexes. This suggests that men and women use different strategies when confronted with increased intraoral pressure during semi-occluded vocal tract exercises. In this study, sEMG provided insight into the mechanism for differences between vocally normal individuals and could help detect compensatory muscle activation during tube phonation in water for people with voice disorders.

Congenital Fibrosis of Extraocular Muscles: A Case Report

Unprogressive unilateral or bilateral limited ocular motility, with or without ptosis, is a hallmark of the uncommon congenital disease known as congenital fibrosis of extraocular muscle (CFEOM). Fibrosis of the extraocular muscle leads to optic nuclear dysplasia or hypoplasia and reduced ocular mobility, which in turn causes it. diverse phenotypes of illness might cause patients to report with diverse presentations.

Cefaleas y neuralgias craneofaciales descritas por autores españoles

Spanish physicians have made important contributions to the nosology of headaches by describing various syndromes. In 1954, Eduardo Tolosa Colomer published the first case of Tolosa-Hunt syndrome, a clinical picture characterized by orbital pain and paralysis of extraocular muscles due to the presence of granulomatous inflammation in the cavernous sinus. In 1980, José Félix Martí Massó described pseudomigraine with cerebrospinal fluid pleocytosis, which manifests with episodes of migraine-type headache, transient neurological deficits, and elevated lymphocytes in the cerebrospinal fluid, usually with a benign prognosis. Since 2002, Juan Pareja and his group have identified several entities including: nummular headache, characterized by pain localized in a small coin-shaped area of the skull; primary trochlear headache, originating in the trochlea, in the superointernal angle of the orbit; epicrania fugax, which manifests with episodes of paroxysmal pain radiating along the surface of the head, following a linear or zigzag trajectory, and idiopathic ophthalmodynia and rhinalgia, which present with pain in the eyeball or nose with no apparent cause. Juan Pareja has also described several trigeminal terminal branch neuralgias, which are characterized by pain limited to the corresponding cutaneous territory and which typically respond to anesthetic blockade of the nerve. Finally, paroxysmal pressing headache, described by the same author, is manifested by brief episodes of unilateral pressing pain without accompanying symptoms. All these descriptions have been documented in scientific publications, and most of them have had a significant impact on clinical practice.

Coexistence of Acetylcholine Receptor (AChR) Antibody Positive Myasthenia Gravis in Two Patients with Hereditary Myopathies Associated with Extraocular Muscle Weakness (P11-11.001)

Coexistence of Acetylcholine Receptor (AChR) Antibody Positive Myasthenia Gravis in Two Patients with Hereditary Myopathies Associated with Extraocular Muscle Weakness (P11-11.001)

Evaluation of non-additive genetic effects on carcass and meat quality traits in Korean Hanwoo cattle using genomic models

The traditional genetic evaluation methods generally consider additive genetic effects only and often ignore non-additive (dominance and epistasis) effects that may have contributed to genetic variation of complex traits of livestock species. The available dense single nucleotide polymorphisms (SNPs) panels offer to investigate the potential benefits of including non-additive genetic effects in the genomic evaluation models. Data from 16 971 genotyped (Illumina Bovine 50 K SNP chip) Korean Hanwoo cattle were used to estimate genetic variance components and prediction accuracy of genomic breeding values (GEBVs) for four carcass and meat quality traits: carcass weight (CWT), eye muscle area (EMA), back fat thickness (BFT) and marbling score (MS). Five different genetic models were evaluated through including additive, dominance and epistatic interactions (additive by additive, A × A; additive by dominance, A × D and dominance by dominance, D × D) successively in the models. The estimates of additive genetic variances and narrow sense heritabilities (ha2) were found similar across the evaluated models and traits except when additive interaction (A × A) was included. The dominance variance estimates relative to phenotypic variance ranged from 1.7–3.4% for CWT and MS traits, whereas, they were close to zero for EMA and BFT traits. The magnitude of A × A epistatic heritability (haa2) ranged between 14.8 and 27.7% in all traits. However, heritability estimates for A × D and D × D epistatic interactions (had2 and hdd2) were quite low compared to haa2 and were contributed only 0.0–9.7% of the total phenotypic variation. In general, broad sense heritability (hG2) estimates were almost twice (ranging between 0.54 and 0.68) the ha2 for all of the investigated traits. The inclusion of dominance effects did not improve the prediction accuracy of GEBV but improved 2.0–3.0% when epistatic effects were included in the model. More importantly, rank correlation revealed that partitioning of variance components considering dominance and epistatic effects in the model would enable to re-rank of top animals with better prediction of GEBV. The present result suggests that dominance and epistatic effects could be included in the genomic evaluation model for better estimates of variance components and more accurate prediction of GEBV for carcass and meat quality traits in Korean Hanwoo cattle.

Facial expression recognition for stress detection: A Conv-XGBoost Algorithm approach

Facial Emotion Recognition (FER) is a powerful tool for gaining insights into human behaviour and well-being by precisely quantifying a wide range of emotions especially stress, through the analysis of facial images. Detecting stress using FER entails meticulously examining subtle facial cues, such as changes in eye movements, brow furrowing, lip tightening, and muscle contractions. To assure effectiveness and real-time processing, FER approaches based on deep learning and artificial intelligence (AI) techniques was created using edge modules. This research introduces a novel approach for identifying stress, leveraging the Conv-XGBoost Algorithm to analyse facial emotions. The proposed model sustain rigorous evaluation techniques, for employing key metrics examination such as the F1 score, validation accuracy, precision, and recall rate to assess its real-world reliability and robustness. This comprehensive analysis and validation proved the model’s practical utility in facial analysis. Integrating the Conv-XGBoost Algorithm with facial emotion analysis represents a promising and highly accurate solution for efficient stress detection. The method surpasses existing literature and demonstrate significant potential for practical applications based on well-validated data.

Enhancing bighead carp cutting: Chilled storage insights and machine vision-based segmentation algorithm development

To enhance market demand and fish utilization, cutting processing is essential for fish. Bighead carp were cut into four primary cuts: head, dorsal, belly, and tail, collectively accounting for 77.03% of the fish's total weight. These cuts were refrigerated at 4 °C for 10 days, during which the muscle from each cut was analyzed. Pseudomonas.fragi proliferated most rapidly and was most abundant in eye muscle (EM), while Aeromonas.sobria showed similar growth patterns in tail muscle (TM). Notably, EM exhibited the highest rate of fat oxidation. TM experienced the most rapid protein degradation. Furthermore, to facilitate the cutting applied in mechanical processing, a machine vision-based algorithm was developed. This algorithm utilized color threshold and morphological parameters to segment image background and divide bighead carp region. Consequently, each cut of bighead carp had a different storage quality and the machine vision-based algorithm proved effective for processing bighead carp.

Comparison of simultaneous prism and cover test (SPCT) and prism and alternate cover test (PACT) measurements with final power of Press-On prism power dispensed

PurposeTo investigate the association of strabismic angle obtained by simultaneous prism and cover test (SPCT) and prism alternate cover test (PACT) with the final power of Press-On prism used in adults with symptomatic strabismus. Subjects and MethodsThe medical records of consecutive patients seen by a single orthoptist at an urban, tertiary care hospital over a 36-month period were reviewed retrospectively. All subjects had been prescribed Press-on prism for diplopia after evaluation with SPCT and PACT measurements at distance fixation. Prism dispensed was chosen by the patient using a trial Press-On prism set. ResultsA total of 244 charts were reviewed. Of these, 108 adult patients had prism dispensed, and 32 had both SPCT and PACT measurements. Mean SPCT measurement was 7Δ (median, 6Δ; range, 3Δ-14Δ); mean PACT, 13Δ (median, 11Δ; range, 8Δ-20Δ). The mean prism power dispensed was 7Δ (median, 6Δ; range, 1Δ-15Δ); this was not significantly different from mean SPCT (P = 0.35). There was a large difference (6Δ) between mean PACT measurements and mean prism dispensed (P < 0.001). At follow-up of 1 year, 21 patients (66%) remained in prism. Nine patients (4%) elected to undergo eye muscle surgery, 7 with horizontal strabismus, 6 of whom had SPCT measurements of >10Δ and PACT measurements of >15Δ. ConclusionsPress-On prism power used was more closely tied to the angle of strabismus obtained by SPCT. Overall success rate of Press-On prism was good when the prism power dispensed was close to the SPCT measurement, suggesting that it is reasonable to initiate treatment with a weaker prism, approximating the SPCT measurement, building up only if there are continuing symptoms.

MultiSenseBadminton: Wearable Sensor–Based Biomechanical Dataset for Evaluation of Badminton Performance

The sports industry is witnessing an increasing trend of utilizing multiple synchronized sensors for player data collection, enabling personalized training systems with multi-perspective real-time feedback. Badminton could benefit from these various sensors, but there is a scarcity of comprehensive badminton action datasets for analysis and training feedback. Addressing this gap, this paper introduces a multi-sensor badminton dataset for forehand clear and backhand drive strokes, based on interviews with coaches for optimal usability. The dataset covers various skill levels, including beginners, intermediates, and experts, providing resources for understanding biomechanics across skill levels. It encompasses 7,763 badminton swing data from 25 players, featuring sensor data on eye tracking, body tracking, muscle signals, and foot pressure. The dataset also includes video recordings, detailed annotations on stroke type, skill level, sound, ball landing, and hitting location, as well as survey and interview data. We validated our dataset by applying a proof-of-concept machine learning model to all annotation data, demonstrating its comprehensive applicability in advanced badminton training and research.

Peribulbar Corticosteroids for Ocular Myasthenia Gravis.

Ocular myasthenia gravis is treated predominantly by oral medications, with the potential for systemic adverse effects. Successful treatment has been achieved using peribulbar dexamethasone. We assessed the effect of peribulbar dexamethasone or triamcinolone (40-mg Triesence), a longer-acting corticosteroid, targeting the peribulbar area as opposed to directly injecting the affected extraocular muscle. This more convenient and secure approach holds the potential for straightforward integration within clinical environments. Retrospective chart review. Five patients were identified that were treated with peribulbar corticosteroids. In 4 of the 5 cases, ophthalmoparesis was unilateral. One case had isolated ptosis, and 4 had both ptosis and ophthalmoparesis. Three of these 4 cases reported complete resolution of symptoms within weeks of a single injection. Improvement lasted between 5 to 6 months, and all patients responded to repeated injections. Peribulbar corticosteroids can be effective in ocular myasthenia gravis. We suggest that longer-acting agents such as triamcinolone are preferable, to reduce injection frequency.

Primary isolated extranodal NK/T-cell lymphoma of the orbit: A case report and diagnostic dilemma

Natural killer T-cell lymphoma (NKTL) is associated with Epstein-Barr virus, a highly malignant tumor that typically arises in the nose and/or paranasal sinuses isolated orbital involvement by NKTL is extremely rare. Herein, we report a case of primary orbital NKTL in a young female patient. A 32-year-old female presented with gradually increasing painful swelling of the right eye. On examination, abaxial proptosis, inferolateral displacement of the eyeball, restricted extraocular muscle movement, and solid mass in the subconjunctival fornix and superior quadrant. The rest of the ocular and systemic examination was unremarkable. Magnetic resonance imaging with contrast of the orbit shows a lobulated mass lesion 35×30×18 mm involving the medial aspect of the right orbit extraconal and superior intraconal space extending up to the preseptal region. Informed consent and biopsy were done and sent for histopathology examination. Histopathological examination shows the spectrum of atypical lymphoid cells, indented or cleaved nuclei and pale to clear cytoplasm, few histiocytes, giant cells, and apoptotic body. To rule out lymphoma, immunohistochemistry (IHC) was advised. On IHC, tumor cells were positive for CD3, D56, CD4 focally, CD7, Ki-67–90% and negative for CD20, CD2, Tdt, PAX5, CD34, CD5, Cd8 leading to a diagnosis of extranodal NKTL of the orbit. To the best of our knowledge, around 20 cases of isolated orbital extranodal NKTL were reported in the literature review. Polymorphic lymphoid cell in a young patient often mimics the inflammatory conditions of orbit. The rarity of this tumor and inflammatory signs make it challenging to identify these tumors early.

Neurophysiologic Monitoring of Oculomotor Nerves During Transorbital Surgery: Proof of Concept and Anatomic Demonstration.

Transorbital neuroendoscopic surgery (TONES) is continuously evolving and gaining terrain in approaching different skull base pathologies. The objective of this study was to present our methodology for introducing recording electrodes, which includes a new transconjunctival pathway, to monitor the extraocular muscle function during TONES. A translational observational study was performed from an anatomic demonstration focused on the transconjunctival electrode placement technique to a descriptive analysis in our series of 6 patients operated using TONES in association with intraoperative neurophysiologic monitoring of the oculomotor nerves from 2017 to 2023. The stepwise anatomic demonstration for the electrode placement and correct positioning in the target muscle was realized through cadaveric dissection. The descriptive analysis evaluated viability (obtention of the electromyography in each cranial nerve [CN] monitored), security (complications), and compatibility (interference with TONES). In our series of 6 patients, 16 CNs were correctly monitored: 6 (100%) CNs III, 5 (83.3%) CNs VI, and 5 (83.3%) CNs IV. Spontaneous electromyography was registered correctly, and compound muscle action potential using triggered electromyography was obtained for anatomic confirmation of structures (1 CN III and VI). No complications nor interference with the surgical procedure were detected. The methodology for introducing the recording electrodes was viable, secure, and compatible with TONES.

The Spiral of Tillaux: dead on accurate; a cadaveric study

ABSTRACT Introduction The Spiral of Tillaux describes the historically accepted insertion distances of the medial rectus, inferior rectus, lateral rectus, and superior rectus from the limbus: 5.5 mm, 6.5 mm, 6.9 mm, and 7.7 mm, respectively. The corneal diameters are historically accepted to be 11.7 mm horizontally and 10.6 mm vertically in adults. We investigated the variability of the insertion distances of the extraocular rectus muscles from the limbus as well as the corneal diameters using eyes from human cadavers and compared our measurements to these historically accepted measurements. Methods A sample of 60 eyes were included. For each eye, a 360 peritomy was conducted and the conjunctiva bluntly dissected to view the sclera. Muscle hooks were utilized to isolate the extraocular rectus muscles. Calipers were used to measure the insertion distances of the rectus muscles as well as the corneal diameters. Results The mean rectus muscle insertions distances from the limbus were medial 5.28 mm, inferior 5.72 mm, lateral 6.40 mm, and superior 6.78 mm. These insertion distances were shorter than the historical benchmarks (p < .01). However, observed maximum distances of the rectus muscles were all greater than the historically accepted benchmarks, with the medial, inferior, lateral, and superior rectus muscles being 6.4 mm, 7.3 mm, 7.4 mm, and 7.8 m from the limbus, respectively. The mean width and height of the cornea were 11.7 mm and 10.7 mm, respectively, and similar to the expected ranges. Conclusion This study concludes that variability does exist from the historically accepted Spiral of Tillaux measurements. In addition, significant variation exists between male and female rectus muscle insertions. However, we did confirm that the rectus muscles followed the same spiral pattern described by the Spiral of Tillaux and concluded that the corneal diameters are consistent with previously accepted values.

Normative measurements of orbital structures on magnetic resonance images; a cross-sectional study with mini review of the literature.

Awareness of normative values of extra orbital structures would provide useful information to interpret the radiological images better and use them for diagnostic purposes. This study aimed to reveal the average values of major extraocular structures measured on magnetic resonance images. In this retrospective cross-sectional study, magnetic resonance (MR) images of 256 orbits of 128 patients were re-interpreted regarding the measurements of major orbital structures. Extraocular muscles, superior ophthalmic vein, and optic nerve-sheath complex were measured on orbital MR images of these patients. The data distributions were presented by box-plot analyses for each parameter, and the measurement results were analyzed regarding gender and age groups. Lateral rectus muscle thickness (LR), inferior rectus muscle thickness (IR), globe position (GP), and interzygomatic line (IZL) values were higher in the male group than in the female group (p values were < 0.001, 0.003, 0.020, and < 0.001 respectively). LR, the thickness of the superior group muscles (SUP GR), IR, superior oblique muscle thickness (SOBL), and the thickness of optic nerve-sheath complex (ON) values indicated a significant relationship between age groups. There was a significant, positive, and low-level correlation between age and LR, SUP GR, and IR values (p values were < 0.001, 0.001, and < 0.001, respectively). This study provides quantitative data on normative values of orbital structures with gender and age group comparisons. Clinicians or surgeons can easily use the measured values to gather diagnostic information from the orbital region.

Expression of Collagen XIII in Tissues of the Thyroid and Orbit With Relevance to Thyroid-Associated Ophthalmopathy.

Antibodies against collagen XIII have previously been identified in patients with active thyroid-associated ophthalmopathy (TAO). Although collagen XIII expression has been described in extraocular muscles and orbital fat, its detailed localization in extraocular and thyroid tissues and the connection to autoimmunity for collagen XIII remain unclear. Our objective was to map the potential targets for these antibodies in the tissues of the orbit and thyroid. We evaluated the expression of collagen XIII in human patient and mouse orbital and thyroid tissues with immunostainings and RT-qPCR using Col13a1-/- mice as negative controls. COL13A1 expression in Graves' disease and goiter thyroid samples was compared with TGF-β1 and TNF, and these were also studied in human thyroid epithelial cells and fibroblasts. Collagen XIII expression was found in the neuromuscular and myotendinous junctions of extraocular muscles, blood vessels of orbital connective tissue and fat and the thyroid, and in the thyroid epithelium. Thyroid expression was also seen in germinal centers in Graves' disease and in neoplastic epithelium. The expression of COL13A1 in goiter samples correlated with levels of TGF-B1. Upregulation of COL13A1 was reproduced in thyroid epithelial cells treated with TGF-β1. We mapped the expression of collagen XIII to various locations in the orbit, demonstrated its expression in the pathologies of the Graves' disease thyroid and confirmed the relationship between collagen XIII and TGF-β1. Altogether, these data add to our understanding of the targets of anti-collagen XIII autoantibodies in TAO.

Normal Diameters of Extraocular Muscles: A Nigerian Retrospective Study.

The thickness of extraocular muscles (EOMs) is important in the management of several conditions associated with EOM enlargement. This study determined the normative values of EOM diameters in adult patients seen at a teaching hospital in Nigeria. The study measured the thickness of the EOMs and the interzygomatic line (IZL) on brain images of 300 patients with non-orbital conditions (150 computed tomography [CT] and 150 magnetic resonance imaging [MRI]) archived in the radiological database of Delta State University Hospital, Nigeria, after ethical clearance. The Statistical Package for the Social Sciences (version 23) was used to obtain descriptive statistics and further compare the variables based on gender, age groups and laterality. The association between parameters was tested using Pearson's correlation test. A probability value of <5% was considered significant. The thickest muscles were the medial rectus (0.42 ± 0.08 cm) and superior muscle group (0.42 ± 0.33 cm) on CT and the inferior rectus (0.40 ± 0.08 cm) on MRI. The diameters were symmetrical with sexual dimorphism in the superior muscle group on CT, medial and lateral recti on MRI and sum of all EOMs on both imaging groups (P < 0.05). The superior muscle group and the sum of all EOMs showed significant age group variations and a positive correlation with age. We noted a positive correlation between each EOM diameter and the sum of all EOMs besides the IZL (P < 0.05). This study offers normative data regarding EOMs that radiologists and ophthalmologists can use to diagnose disease conditions that cause EOM enlargement and further assess their response to treatment.