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Show LETTERS TO THE EDITOR Radiation Retinopathy After Fractionated Stereotactic Conformal Radiotherapy for Primary Intraorbital Optic Nerve Sheath Meningioma There are just two reported cases of radiation retinopathy after fractionated stereotactic radiotherapy ( SFRT) for optic nerve sheath meningioma ( ONSM) ( 1,2). We report a further case of radiation retinopathy secondary to fractionated stereotactic conformal radiotherapy ( SCRT) for biopsy- proven ONSM. A 42- year- old woman developed increasing proptosis of the right eye. Visual acuity was 20/ 16 in both eyes. Color vision was normal and there was no relative afferent pupillary defect. Visual fields were normal. Hertel exophthalmometry disclosed 9 mm of right axial proptosis. Ophthalmoscopy was normal. MRI showed a well- demarcated round intraconal orbital mass that abutted the globe and exhibited contrast enhancement ( Fig. 1). A biopsy of the tumor disclosed an epithelial membrane antigen ( EMA)- positive meningothe-lial meningioma ( Fig. 2). The patient underwent fractionated SCRT to a total dose of 54 Gy in 30 divided fractions of 1.8 Gy The maximum dose to the posterior retina was 54 Gy. The anterior half of the retina received a dose of < 16.2 Gy. Two years after completion of radiotherapy, several cotton wool spots were noted in the right posterior pole ( Fig. 3). Visual acuity remained 20/ 16 in each eye. Blood glucose level and antinuclear antibody were normal. A retinal fluorescein angiogram showed areas of capillary closure, microaneurysms, and venous staining in the right fundus ( Fig. 3). Visual acuity dropped over the next 6 months to 20/ 40, and new blot hemorrhages were noted, but no edema or proliferative changes were seen. In the first reported case of radiation retinopathy after SFRT for ONSM ( 1), the patient received the same treatment as did our patient: 30 fractions of 1.8 Gy for a total dose of 54 Gy. The posterior retina received 27- 48 Gy. Fluorescein angiography showed findings similar to those of our patient. These changes worsened over the next few months despite laser photocoagulation. The second report consisted of a letter by Levi ( 2) about a 57- year- old man diagnosed with optic nerve sheath meningioma who underwent SFRT with the same tumor dose ( 2). Five years J Neuro- Ophthalmol, Vol. 27, No. 2, 2007 after treatment, visual acuity dropped, and fluorescein angiography showed findings similar to those of our patient. Our case differs from the two previously reported cases in that the diagnosis was biopsy- proven and that 3D conformal methods were used to minimize collateral radiation damage. Many patients have now received radiotherapy for ONSM, and this is only the third reported case of radiation retinopathy. Our patient may have been relatively more FIG. 1. Postcontrast Tl axial MRI shows an enhancing mass in the intraconal space of the right orbit that abuts the globe. FIG. 2. Tumor biopsy specimen ( hematoxylin and eosin) shows a syncytial growth pattern and no mitotic figures, consistent with a meningothelial meningioma, World Health Organization Grade 1. 143 J Neuro- Ophthalmol, Vol. 27, No. 2, 2007 Letters to the Editor FIG. 3. A. Right fundus photograph taken 2 years after completion of radiotherapy shows multiple cotton wool spots and a retinal hemorrhage inferior to the fovea, findings consistent with radiation retinopathy. B. Right fundus fluorescein angiogram shows late perivenous staining. vulnerable to radiation retinopathy because of the biopsy and the fact that the treatment field included the posterior retina, as in the case reported by Subramanian et al ( 1). In the case reported by Levi ( 2), the radiation dose to the posterior retina and the proximity of the tumor to the globe were not mentioned. Whether ONSM would respond to doses lower than 54 Gy in 30 fractions ( the standard dose) is not known. It may be prudent to examine the possibility of treatment using a lower radiation dose, particularly for ONSMs that about the globe. Radhika Krishnan, MA ( Cantab), MRCOphth Indu Kumar, MRCOphth Graham Kyle, FRSCEd, FRCOphth Ophthalmology Department Walton Daycase and Outpatient Centre University Hospital Aintree Liverpool, UK radhikrishnan2004@ yahoo. co. uk David John Husband, MRCP ( UK), FRCR Clatterbridge Centre for Oncology Bebington, Cheshire, UK REFERENCES Subramanian PS, Bressler NM, Miller NR. Radiation retinopathy after fractionated stereotactic radiotherapy for optic nerve sheath meningioma. Ophthalmology 2004; 111: 565- 7. Levi L. Radiation retinopathy after therapy for meningioma. Ophthalmology 2005; 112: 1484. Ophthalmoplegia and Lid Retraction With Normal Initial Orbit CT Imaging in Extraocular Muscle Metastases as the Presenting Sign of Breast Carcinoma We report a case of bilateral limitation of eye movements, upper lid ptosis, and lid retraction on down-gaze caused by extraocular muscle infiltration in metastatic breast cancer. A 45- year- old woman presented in July 2003 with a 4- month history of horizontal diplopia that was worse in right gaze. The diplopia did not fluctuate during the day and bore no relationship to rest or exercise. The patient was otherwise in good health. Examination showed a slight left upper lid ptosis without fatigability, left upper lid retraction on downgaze ( no lag and no globe retraction in primary gaze), left orbicularis oculi weakness, impaired abduction and supraduction of the right eye, and impaired adduction of the left eye. Exophthalmometry was 17 mm in both eyes ( base 110 mm). The remainder of the neuro- ophthalmologic examination was normal. Thyroid- stimulating hormone ( TSH) level was normal, and acetylcholine receptor antibody titer and intravenous edrophonium test results were negative. A contrast-enhanced brain and orbit CT scan was normal ( Fig. 1). 144 © 2007 Lippincott Williams & Wilkins Letters to the Editor J Neuro- Ophthalmol, Vol. 27, No. 2, 2007 FIG. 1. Coronal ( A) and axial ( B) precontrast orbit CT scans performed at initial presentation show no abnormalities. FIG. 2. Coronal ( A) and axial ( B) precontrast CT scans performed 9 months after initial presentation disclose bilateral enlargement of extraocular muscles and their tendons. Two months later, she complained of bilateral ocular irritation and tearing. Examination showed increased left upper lid ptosis and conjunctival chemosis of the left eye. Forced duction testing showed impaired supraduction of the right eye. At this point, the possibility of thyroid orbitopathy was considered, and symptomatic treatment for eye irritation was prescribed. Five months after the initial visit, she reported left eye pain on upgaze and was found to have markedly impaired horizontal and upgaze movements in both eyes. There was eyelid retraction with exposure keratopathy in the left eye. An orbit CT scan 8 months after symptom onset showed bilateral diffuse enlargement of the extraocular muscles and tendons suggestive of idiopathic orbital inflammation (" pseudotumor" or " myositis") ( Fig. 2). Treatment with 50 mg/ day prednisone by mouth for 2 weeks followed by a 3- day course of 1 g/ day methylprednisone intravenously was ineffective. A left orbital biopsy performed 10 months after symptom onset showed the presence of metastatic adenocarcinoma. Subsequently she was found to have bilateral breast cancer. Extraocular muscle ( EOM) metastasis has been documented in patients with advanced breast cancer. Most publications are single case reports. In a major review on the nonthyroid causes of EOM disease, Lacey et al ( 1) found 12 cases of EOM metastases ( 3 from breast cancer) in 103 patients. Our case resembles that of Spitzer et al ( 2), but the diagnosis in their patient was made immediately by orbit MRI, whereas our patient's diagnosis was delayed because the initial imaging study, an orbit CT scan, failed to show any abnormalities. To our knowledge, there has been no previous report of a patient with normal imaging results and EOM metastases. Is CT too insensitive for the early diagnosis of EOM metastases? The conclusion of several studies comparing CT and MRI in orbital and ocular metastases studies is that whereas MRI is the preferred technique for intraocular tumors, the two techniques are comparable for orbital metastases ( 3). Later in the patient's course, when she developed pain on upgaze and the orbit CT showed enlarged extraocular muscles, we were led to an erroneous diagnosis of idiopathic orbital inflammation. The correct diagnosis could have been reached on the basis of noting the presence of ptosis and lid retraction on downgaze, an association described as a red flag for neoplastic lid infiltration ( 4). Lid retraction on downgaze must be distinguished from lid retraction in primary gaze and from lid lag, which are, of course, characteristic of Graves disease. Lid retraction in primary gaze position, lid retraction on downgaze, and lid lag may all be manifestations of a similar phenomenon, whether induced by inflammation ( Graves disease or orbital myositis) or infiltration. The literature on these different signs is often confusing. For us, lid retraction in primary gaze and retraction in downgaze are static phenomena, with the former being due to a shortening of the levator muscle and the latter to a noncompliant levator. We think of lid lag as a dynamic phenomenon in which the lid cannot loosen up quickly but eventually does. Interestingly, lid retraction and lid lag were described in the case of breast cancer metastatic to the extraocular muscles reported by Spitzer et al ( 2). It is a widely held belief that as a result of fibrotic (" scirrhous") retraction, metastatic breast cancer to the orbit causes enophthalmos. The same thing may occur with orbital metastasis in other types of cancer such as gastrointestinal, lung, and prostate ( 5). Metastatic breast cancer to the orbit can also manifest as a space- occupying lesion and cause exophthalmos. Our patient did not have either enophthalmos or exophthalmos. With this report, we provide further documentation that ophthalmoplegia may be the presenting manifestation of metastatic breast cancer to the extraocular muscles, 145 J Neuro- Ophthalmol, Vol. 27, No. 2, 2007 Letters to the Editor and we show that orbital CT scanning may initially be insensitive to this condition. We caution that lid retraction not be taken as pathognomonic of inflammatory shortening of the levator muscle; it may be a sign of cancer. Katie Luneau, MD Ophthalmology Department Centre Hospitalier de l'Universite de Montreal Montreal, Quebec, Canada k_ luneau@ hotmail. com Julie Falardeau, MD, FRCSC Casey Eye Institute Portland Oregon Isabelle Hardy, MD, FRCSC Patrick R. Boulos, MD, FRCSC Ophthalmology Department Hopital Maisonneuve- Rosemont Montreal, Quebec, Canada Dan Boghen, MD, FRCPC Neurology Service Centre Hospitalier de l'Universite de Montreal Montreal, Quebec, Canada REFERENCES 1. Lacey B, Chang W, Rootman J. Nonthyroid causes of extraocular muscle disease. Surv Ophthalmol 1999; 44: 187- 213. 2. Spitzer SG, Bersani TA, Mejico LJ. Multiple bilateral extraocular muscle metastases as the initial manifestation of breast cancer. JNeuroophthalmol 2005; 25: 37- 9. 3. Peyster RG, Shapiro MD, Haik BG. Orbital metastasis: role of magnetic resonance imaging and computed tomography. Radiol Clin North Am 1987; 25: 647- 62. 4. Uddin JM, Rose GE. Downgaze " hang- up" of the upper eyelid in patients with adult- onset ptosis: an important sign of possible orbital malignancy. Ophthalmology 2003; 110: 1433- 6. 5. Goldberg RA, Rootman J, Cline RA. Tumors metastatic to the orbit: a changing picture. Surv Ophthalmol 1990; 35: 1- 24. 146 © 2007 Lippincott Williams & Wilkins |