A case of orbital myositis complicated with optic neuropathy--analysis of the pathological mechanism of optic neuropathy from magnetic resonance imaging findings

BACKGROUND: We observed a rare case of orbital myositis involving the optic nerve. Case: A 52-year-old woman complained of visual disturbance, lid swelling, ocular pain, and conjunctival injection in her right eye. Her corrected vision was 0.15 in the right eye and 1.2 in the left eye. Relative afferent pupillary defect(RAPD) and central scotoma in visual field test were noted in the right eye. Ocular movement of her right eye was moderately disturbed in all directions. Although laboratory data showed elevation of erythrocyte sedimentation rate, other hematological data such as thyroid function, autoimmune antibodies, and viral infection antibodies were normal. Magnetic resonance imaging(MRI) findings showed compression of the optic nerve at the orbital apex by marked thickening of the right lateral rectus muscle and superior rectus muscle, and inflammation directly invading the optic nerve. Based on the above findings, we diagnosed the case as orbital myositis complicated with optic neuropathy, and started corticosteroid therapy. Her right corrected vision improved dramatically, and the RAPD, central scotoma, and lid swelling disappeared shortly after administration. Enlargement of the extraocular muscles was still present one month after corticosteroid therapy. CONCLUSION: MRI findings suggested that optic neuropathy in this case was induced not only by mechanical compression by the enlarged extraocular muscles at the orbital apex but also by direct inflammatory infiltration from the extraocular muscles.     

Correlation of CT Scanning and Pathologic Features of Ophthalmic Graves' Disease

Correlating the CT scan features of patients with orbital Graves' disease with histopathologic observations allows one to focus more specifically on the distinguishing features of this disease with future research implications. Both CT scanning and pathologic studies have shown clearly that the extraocular muscles are the primary focus of the disease. Swelling of the extraocular muscles generally occurs within their bellys with sparing of the tendons. This contrasts with idiopathic inflammation of the muscles or myositis, which tends to involve the tendon as well. All of the associated findings in orbital Graves' disease probably flow from the enlarged volume of the extraocular muscles: proptosis, bowing of the medial lamina papyracea to accommodate the swollen belly of the medial rectus muscle, venous engorgement from stasis induced by direct compression of the orbital venous drainage, conjunctival and lid swelling, and lacrimal gland enlargement. Both radiographic and pathologic changes in the orbital fat are secondary and comparatively insignificant. While there appears to be no selective inflammation of the optic nerve meninges or the perineural connective tissues, enlargement of the extraocular muscle bellys where they converge at the crowded orbital apex brings about compression of the optic nerve, impairs its function, and causes visual decrease. Lymphocytic and plasmacytic infiltration along with edema within the endomysium of the extraocular muscles leads to the activation of fibroblasts with the production of acid mucopolysaccharides and progressive fibrosis. It is not known what attracts the lymphocytes to the extraocular muscles, why certain extraocular muscles are affected preferentially, why the disease may be asymmetrically unilateral, and whether a defect in T cell or B cell functions (or both) is immunologically at fault.     

Neuroendocrine Tumor (Carcinoid) Metastatic to Orbital Extraocular Muscle: Case Report and Literature Review

Purpose: To report a patient who showed neuroendocrine tumor (carcinoid) metastasis to the medial rectus muscle and to review patients’ characteristics of carcinoid metastases to the extraocular muscles.

Case: A 72-year-old woman, who initially presented with spindle-shaped enlargement of the right medial rectus muscle, was followed for 3 years with a diagnosis of orbital myositis. Initial biopsy of the medial rectus muscle showed inflammation only. She showed remission and exacerbation of right proptosis and eyelid swelling, which responded to oral and intravenous steroids. On the occasion of abdominal computed tomography for ischemic colitis, a large retroperitoneal mass was detected and diagnosed as well-differentiated neuroendocrine tumor. The gradual increase of the medial rectus muscle with optic nerve compression, and hence, visual reduction, prompted a second excisional biopsy of the medial rectus mass, which proved to be neuroendocrine tumor metastasis. Whole body 2-[¹⁸F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography fused with computed tomography revealed abnormal uptake only in the right orbit (maximum standardized uptake value: SUVmax?=?3.83), and the patient underwent radiation to the right orbit with the subsidence of the residual mass.

Results: The literature review found 15 patients, including this patient, with neuroendocrine tumor metastases to the extraocular muscles. Frequent symptoms and signs were diplopia, proptosis, and ocular motility limitation.

Conclusions: Neuroendocrine tumor appears to have propensity to extraocular muscle metastases and its slow growth might pose difficulty in differential diagnoses of orbital myositis.     

Systemic sarcoidosis presenting initially with bilateral orbital and upper lid masses

A patient with systemic sarcoidosis presented initially with bilateral orbital and upper lid masses. Computed tomographic scan showed bilateral anterior orbital and upper lid masses, diffuse irregular thickening of the rectus muscles, circumferential cuffing of both globes, and irregular thickening of the distal portion of the right optic nerve sheath. A biopsy specimen of the right upper lid mass showed fibroadipose tissue with multiple noncaseating granulomas. Bilateral pulmonary hilar lymphadenopathy, a positive gallium scan, anergy by skin testing, and the presence of erythema nodosum confirmed the diagnosis of systemic sarcoidosis.     

Lateral rectus dermoid cyst presenting as incomitant esotropia

A 24-year-old male presented with decreased vision associated with inward deviation of his left eye since childhood and gradually progressive prominence of left eye for 6 months. Left eye examination revealed visual acuity of 2/60, convergent squint with restricted abduction and medial dystopia. Computed tomography (CT) scan showed a well-circumscribed mass with fat fluid levels temporal to the optic nerve indistinguishable from the left lateral rectus. Intraoperatively, a well-encapsulated mass was identified within the lateral rectus muscle which was confirmed as dermoid cyst on histopathology. Patient subsequently underwent surgical correction of his esotropia and the final cosmetic outcome was satisfactory. Dermoid cysts are common orbital lesions usually found overlying suture lines. A dermoid cyst presenting within the ocular muscles is a rare entity. Deep dermoid cyst should be considered as one of the differentials for focal enlargement of extraocular muscles.     

Evaluation of extraocular muscle enlargement in dysthyroid ophthalmopathy

PURPOSE: To evaluate the extraocular muscle enlargement in dysthyroid opthalmopathy. METHOD: Extraocular muscle enlargement was assessed by orbital computed tomography (CT) in 573 patients with dysthyroid ophthalmopathy in order to investigate the frequency and exact location of extraocular muscle enlargement and the clinical features of related ocular symptoms in patients with dysthyroid ophthalmopathy. RESULTS AND CONCLUSION: 187 patients (38% of the total) showed evidence of extraocular muscle enlargement on CT images, and this disorder were more frequent in male patients than in female patients. Extraocular muscle enlargement was also more frequently seen in older patients than in younger patients. Enlargement of a single muscle was found in 55% of the 187 patients, with the most frequently affected muscle being the inferior rectus muscle. When multiple muscles were enlarged, the inferior rectus muscle was the most frequently affected, followed by the medial rectus muscle. Of the clinical findings specific to dysthyroid ophthalmopathy examined in the present study, the incidence of exophthaomos, upper lid swelling, superior limbic keratoconjunctivitis, keratitis, diplopia, and dysthyroid optic neuropathy were significantly increased in patients with dysthyroid ophthalmopathy, indicating a close relationship between these findings and the underlying disease, but the incidence of upper lid retraction was not significantly increased.     

Reactivation of Thyroid Associated Orbitopathy Following Trauma with Intraorbital Foreign Body

A 63-year-old female with mild, bilateral, stable thyroid-associated orbitopathy sustained trauma resulting in glass foreign bodies embedded on the left ocular surface and left lateral orbital extraconal and intraconal space. After 2 orbitotomies including a failed attempt to remove the intraconal foreign body and poor response to oral steroids, she developed severe, progressive left periorbital edema and 9?mm of relative proptosis. Serial, post-operative imaging demonstrated worsening inflammatory changes along the surgical tract, which slowly improved over several months, with simultaneously worsening proptosis and enlargement of the left inferior and medial rectus muscles consistent with worsening thyroid orbitopathy. She subsequently underwent unilateral 3-wall orbital decompression with improvement in her symptoms. Periorbital trauma with orbital foreign bodies and related surgical trauma may result in reactivation of thyroid-associated orbitopathy.     

Sudden Visual Loss and Total Ophthalmoplegia after Brain Surgery

A 19-year-old woman underwent an occipital craniotomy for removal of a left intraventricular glioblastoma under general anaesthesia and in prone position. Postoperatively she complained of blindness of the right eye. Ocular examination revealed mild proptosis and total ophthalmoplegia of the right eye. Computerized tomography (CT) of the orbits revealed right exophthalmos and enlargement of the extraocular muscles without optic nerve compression. CT angiography showed dilated right supraorbital and supratrochlear arteries without evidence of emboli. Treatment with intravenous methylprednisolone and oral acetazolamide was given. The ocular motility defect improved but the visual loss persisted. As has been emphasized in many similar situations adequate intra-operative ocular protection may reduce such complications.     

Orbital pseudotumor, differential diagnosis

A 66-year-old white male presented with complaints of redness of his left eye, blurred vision, lid edema, and an intermittent throbbing pain above his left eye for 4 days. Significant clinical findings included mild hyperemia and edema of the left upper lid, marked engorgement and tortuosity of the conjunctival and episcleral vessels, mild chemosis, and extreme limitation of the extraocular movements of the left eye in all directions of gaze, especially adduction. This eye also showed a measurable proptosis with positive retropulsion. Pupillary responses and color vision were normal in both eyes. A CT scan revealed an enlarged medial rectus muscle, including its tendinous insertion with a normal cavernous sinus. On the basis of the clinical findings and the CT scan, a diagnosis of orbital pseudotumor was made. The patient was treated with high dose systemic prednisone, which resulted in a dramatic improvement of symptoms and signs.     

Neurofibromatosis Type 2: Optic Nerve Sheath Meningioma in one Orbit,Intramuscular Schwannoma in the Other

A highly unusual patient with neurofibromatosis type 2 (NF2) presenting with simultaneous bilateral orbital tumors is described. A 12-year-old girl with a family history of NF2 was examined because of bilateral proptosis. Visual acuities were light perception RE and 20/40 LE. Magnetic resonance imaging studies showed bilateral cerebellopontine angle tumors, a tumor surrounding the right intraorbital optic nerve, and a large left lateral orbital mass mixed with the lateral rectus muscle. The histopathological diagnoses following incisional biopsies were right optic nerve sheath meningioma and left intramuscular schwannoma. The left-sided orbital schwannoma and the right-sided vestibular schwannoma were treated with fractionated stereotactic radiotherapy. This patient enlarges the spectrum of clinical presentations that can be encountered at young age in patients with NF2.     

Exophthalmos in myelodysplastic syndrome

A case of myelodysplastic syndrome (MDS) who suffered alternating proptosis was reported. A 57-year-old Japanese man with MDS developed acute painful left proptosis with eyelid edema, conjunctival injection, visual disturbance, and restriction of eye movements. This lasted for 3 weeks. Computerized tomography (CT) showed swelling of the lateral and medial rectus muscles and the optic nerve, as well as a retrobulbar mass. Later, a similar painful right proptosis with severe conjunctival chemosis developed. CT showed only bilateral mild optic nerve swelling. The visual acuity of the right eye decreased to null even after remission of the proptosis. The patient died due to myocardial infarction and underwent autopsy. The right optic nerve stroma was found to be increased over that of the left. Cellular infiltration was noted in the left optic nerve and the retrobulbar connective tissue. This self-limiting and relapsing proptosis was apparently related to MDS. This is only the second MDS case with such severe ophthalmological symptoms reported in the literature.     

Normative measurements of Korean orbital structures revealed by computerized tomography

PURPOSE: The purposes of this study were to establish criteria for the diameters of normal extraocular muscles, the width of the optic nerve, and the globe position as revealed by CT, and to investigate the effects of age and sex on these parameters in the Korean population. SUBJECTS AND METHODS: Diameters of extraocular muscles (medial, lateral, superior complex, and inferior rectus), distance from the interzygomatic line to the posterior margin of the globe, width of the optic nerve-sheath complex, and length of the interzygomatic line were calculated for 214 patients on axial and direct coronal CT images, and the effects of age and sex were analyzed. RESULTS: Normal range for the diameters as given by mean+/-2SDs of extraocular muscles were medial rectus, 2.2--5.4 mm; lateral rectus, 2.1--4.9 mm; inferior rectus, 2.5--5.7 mm; and superior complex group, 2.6--6.4 mm. The mean optic nerve-sheath complex was 4.1 mm and the values ranged from 2.9 mm to 5.3 mm. The mean length of the interzygomatic line was 103.8 mm. The normal posterior position of the globe as here designed was 11.2 mm behind the interzygomatic line (range, 6.4--15.3 mm). All parameters under study were a little larger in males than females. Statistically, however, there was no significant difference between males' and females' results, nor between the various age groups (p>0.05). CONCLUSION: Our CT results may help clinical ophthalmologists to accurately assess enlargement of the extraocular muscles and the optic nerve as well as aiding in the evaluation of exophthalmos.     

Computerized tomography in the diagnosis of the congenital fibrosis syndrome

A patient with congenital ptosis and inferior rectus fibrosis is described. Marked atrophy of the left inferior rectus muscle was demonstrated by orbital computerized tomography (CT). Computerized tomographic findings in this patient and a series of 20 patients with no ocular disease and normal motility indicate that CT is a valuable tool for the evaluation of extraocular muscle size when qualitative comparison is made between corresponding muscles in the same patient.     

Orbital rhabdomyosarcoma metastatic to the contralateral orbit: a case report

OBJECTIVE: To report a rare presentation of metastatic orbital rhabdomyosarcoma and the corresponding findings on magnetic resonance imaging (MRI). DESIGN: Interventional case report. RESULTS: A 29-year-old white man was diagnosed with rhabdomyosarcoma of the left sinus and orbit for which he was treated with chemotherapy and radiation. Eighteen months after diagnosis, he returned with subacute right eye pain and dysmotility of his extraocular muscles. MRI revealed solitary enlargement of the right medial rectus muscle, and thyroidopathy was suspected. Over the next 2 months, symptoms progressed, and proptosis developed. MRI showed infiltration of seven extraocular muscles. A biopsy of right orbital tissues and the right medial rectus muscle was performed. Special tissue typing confirmed metastatic alveolar rhabdomyosarcoma. The patient underwent palliative radiation therapy and chemotherapy, but he ultimately died of disseminated disease. CONCLUSIONS: Rhabdomyosarcoma can rarely metastasize to the extraocular muscles. Earlier recognition of orbital metastasis through radiographic and biopsy findings, along with prompt and aggressive treatment, may prevent fulminant spread of rhabdomyosarcoma.     

Optic Nerve Cysticercosis: Case Report and Review of Current Management

The authors present a case of optic nerve cysticercosis in a 32-year-old patient who presented with sudden blurring of vision in the left eye and a transient visual improvement on systemic steroids. The ocular findings were unremarkable other than a relative afferent pupillary defect (RAPD). An ultrasound of the orbit, CT and MRI scans revealed a cystic lesion in the orbital portion of the optic nerve close to the eyeball. A presumed diagnosis of optic nerve cysticercosis was made on the basis of imaging and a positive serum ELISA. The patient improved dramatically on a 4-week therapeutic trial of albendazole and oral steroids. The post-treatment ultrasound and CT scan showed an involution of the cyst with some residual thickening of the optic nerve.     

Optic nerve cysticercosis: case report and review of current management

The authors present a case of optic nerve cysticercosis in a 32-year-old patient who presented with sudden blurring of vision in the left eye and a transient visual improvement on systemic steroids. The ocular findings were unremarkable other than a relative afferent pupillary defect (RAPD). An ultrasound of the orbit, CT and MRI scans revealed a cystic lesion in the orbital portion of the optic nerve close to the eyeball. A presumed diagnosis of optic nerve cysticercosis was made on the basis of imaging and a positive serum ELISA. The patient improved dramatically on a 4-week therapeutic trial of albendazole and oral steroids. The post-treatment ultrasound and CT scan showed an involution of the cyst with some residual thickening of the optic nerve.     

Orbital, osseous, meningeal and cerebral findings in oculodermal melanocytosis (nevus of Ota). Clinico-histopathologic correlation in 2 patients]

In two patients suffering from congenital oculodermal melanocytosis (nevus of Ota) orbital, osseous, meningeal, and cerebral manifestations are documented. In a 38-year-old European with a nevus of Ota on the right side an ipsilateral orbital tumor was diagnosed and surgically removed. The histological examination revealed a primary spindle shaped malignant melanoma of the orbit. In addition, many benign melanocytes were found in the optic nerve, in the extraocular muscles, in the orbital fat tissue, and in the dura of the sphenoid. In a 17-year-old Ethiopian with a nevus of Ota of the right side an increase in size of the pigmented process was observed during puberty in the orbital fat tissue, in the extraocular muscles, in the optic nerve, in the periorbital bones, in the temporal muscle, and in the cortex of the frontal brain lobe. A deep excision from the lower eye lid revealed a histologically benign oculo-orbito-dermal melanocytosis. An irradiation was performed because of growth again after segmental excision, however without success. In the ipsilateral eye a secondary open-angle glaucoma was diagnosed. In the nevus of Ota an involvement of the orbit and of the meningo-cerebral tissue must be considered.     

Evaluation of extraocular muscle enlargement in dysthyroid ophthalmopathy.

PURPOSE: To evaluate extraocular muscle enlargement (EME) in dysthyroid ophthalmopathy. METHODS: EME was assessed by orbital computed tomography (CT) in 573 patients with dysthyroid ophthalmopathy in order to investigate the frequency and exact location of EME and the clinical features of related ocular symptoms in patients with dysthyroid ophthalmopathy. RESULTS: Of the 573 patients examined, 187 patients (38%) showed evidence of EME on CT images. This disorder was more frequent in male patients than in female patients. EME was also more frequently seen in older patients than in younger patients. Enlargement of a single muscle was found in 55% of the 187 patients, with the most frequently affected muscle being the inferior rectus muscle. When multiple muscles were enlarged, the inferior rectus muscle was the most frequently affected, followed by the medial rectus muscle. CONCLUSIONS: Of the clinical findings specific to dysthyroid ophthalmopathy examined in the present study, the incidence of exophthalmos, upper lid swelling, superior limbic keratoconjunctivitis, keratitis, diplopia, and dysthyroid optic neuropathy was significantly increased in patients with dysthyroid ophthalmopathy, indicating a close relationship between these findings and the underlying disease, but the incidence of upper lid retraction was not significantly increased.     

Graves'' ophthalmopathy: I. Simple CT estimates of extraocular muscle volume.

Graves' ophthalmopathy is an autoimmune inflammatory process affecting primarily the extraocular muscles. The enlargement of these muscles is responsible for most of the important manifestations of the disease, including proptosis, lid retraction, diplopia, and optic neuropathy. Recently the optic neuropathy has been shown to correlate with extraocular muscle volume as determined by computed tomography (CT). In the present study simplified measures of the extraocular muscles imaged by CT are described, which also correlate highly with the development of optic neuropathy.     

眼外肌运动神经眶内段的应用解剖

目的 为临床眶内手术避免眼外肌运动神经损伤提供解剖学资料。方法 采用显微解剖学技术对60侧成人动眼神经、滑车神经和外展神经的位置、走行、毗邻进行解剖学观察。结果（1）滑车神经多在上斜肌后1/3段的眶面入肌,在滑车神经与上睑提肌交叉处,额神经紧邻滑车神经外侧;（2）外展神经入肌点有动脉伴行者占86.67%,上下3等分外直肌的肌腹,入肌点在肌的中1/3份者66.67%;（3）动眼神经上干出总腱环后行于上直肌与视神经之间,并分支入上直肌和上睑提肌。动眼社会下干分出内直肌支、下直肌支和下斜肌支。内直肌支经视神经下方向内前斜行至内直肌。下直肌支有2～5条分支,入肌点多在肌的后1/3部。下斜肌支沿下直肌的外上方前行入下斜肌,是动眼神经分支中行程最长的一支。结论 经颅开眶,在上斜肌与上睑提肌、上直肌之间的间隙入路手术时应注意保护滑车神经。肌锥内后部手术在保护好视神经、眼动脉及其分支等结构的同时,还应注意保护动眼神经和外展神经。