Ординатура / Офтальмология / Английские материалы / Clinical Ophthalmic Echography_Harrie_2008

TA is a 21-year-old man who was hit in the right eye with a racquetball. He had taken his protective goggles off because they had fogged up and were interfering with his game. He noted the immediate onset of severe pain and rapid reduction in his vision. He presented at the hospital emergency room within an hour and the ophthalmologist was called in for a consultation. He noted vision in that eye of hand motions at 1 m, intraocular pressure of 25 mm, a total eight-ball hyphema in the anterior chamber, and no view of the fundus.

The patient was referred for echography. B-scan revealed a partial posterior vitreous detachment and vitreous incarceration at the superior equator that was suspicious for a choroidal rupture. There was also the appearance of choroidal edema with some degree of hemorrhage (Fig. 170). A-scan detected moderate intravitreal opacities consistent with hemorrhage. It was elected to watch the patient and treat the elevated pressure with topical medications. The posterior segment was followed daily with ultrasound. The vitreous cleared over several days and the fundus could be visualized. The probable rupture site appeared to have selfsealed and the retina was attached. Surgery was not felt to be indicated.

Uveitic conditions can result in media opacities that obscure a view of the posterior segment. Chronic inflammation may lead to anterior chamber reaction, posterior synechiae with a miotic, or, ultimately, an occluded pupil and cataract formation. Such sequelae of uveitis can result in a hazy view of the vitreous cavity and fundus.

FIG. 170. Top: B-scan of choroidal edema (arrow). Bottom: A-scan of vitreous hemorrhage ( first arrow) and choroidal edema (second and third arrows)

Such patients often come to cataract surgery and a preoperative ultrasound is mandatory to evaluate the globe.

FA is a 45-year-old woman who presented with complaints of poor vision in her right eye for several months. She had waited for her medical insurance to become effective before seeking medical attention. She initially experienced a red, painful eye, but it had become less irritated over time. Examination found visual acuity in the right eye of 20/80 and in the left eye of 20/20. Intraocular pressure measured 2 mm OD and 15 mm OS. Slit-lamp examination demonstrated 2+ mutton-fat keratic precipitates, 270° of posterior synechiae with a fixed pupil, and a 3+ nuclear sclerotic cataract. The posterior segment could not be visualized.

Echography revealed a partial posterior vitreous detachment with mild intravitreal dotlike opacities. On extreme peripheral view with the B-scan, a high

FIG. 171. Immersion scan of cyclitic membrane (arrow)

FIG. 172. Twenty-megahertz immersion scan of ciliary body detachment (arrow)

reflective membrane was detected retrolentally. An immersion scan was performed and demonstrated a cyclitic membrane bridging the temporal to the nasal ciliary body (Fig. 171). A shallow traction detachment of the ciliary body was present (Fig. 172) that explained the relative hypotony in this eye.

The crystalline lens is remarkable in its ability to focus light on the retina with sufficient plasticity to change shape as the ciliary muscles contract. Lens opacities are ubiquitous as people age and generally require cataract surgery if they interfere with vision. Cataracts that obscure a view of the intraocular contents are an indication for echography. Less dense opacities with an atypical presentation, such as a sector cataract in a younger patient, should also be investigated by ultrasound.

TB is a 43-year-old man with complaints of a film over part of the vision in his right eye for several months. It had seemed to descend from the lower part of his visual field and grow upwards into the center of his vision. Examination demonstrated best corrected vision in his right eye of 20/60-2 and in his left eye of 20/20. His pupils were equal in size and reactive to light without an afferent defect. Slit-lamp examination discovered a sectorial cortical and posterior capsular lens opacity in the superior part of his lens that was encroaching into the visual axis. Dilated fundus examination was unremarkable with a normal retinal periphery. Because of his relatively young age and the unusual nature of the lens opacity, he was referred for immersion ultrasound examination.

Echography revealed a normal posterior segment. Immersion scanning was done using a scleral shell filled with methylcellulose and the anterior segment was visualized. A solid echodense mass was seen in the ciliary body in contact with the inferior pole of the lens (Fig. 173). The diagnosis was consistent with a malignant melanoma of the ciliary body.

FIG. 173. Immersion scan of melanoma (small arrow) touching lens (large arrow)

Inadequate visualization of the fundus by the ophthalmoscope should prompt an echographic evaluation of the cataractous eye, especially in a patient who has not been followed over time by his doctor as the cataract progresses. The documentation of a thorough fundus examination within the past couple of years substantially reduces the chances of an unsuspected intraocular melanoma hiding behind media opacity such as a cataract.

TS is a 67-year-old woman who had not had an eye examination for several years and complained of progressively decreasing vision in her left eye for over a year. Clinical examination demonstrated a moderately dense nuclear sclerotic and cortical cataract that hindered adequate visualization of the entire fundus. Cataract surgery was scheduled and biometry was performed. There was some difficulty in obtaining a consistent axial length and because the fundus could not be completely examined she was referred for echography.

Ultrasound revealed a solid mushrooming mass near the temporal equator (Fig. 174). A-scan examination demonstrated low-to-medium, regular internal reflectivity with moderate spontaneous internal vascularity (Fig. 175). These findings were highly consistent with a malignant melanoma of the choroid. Cataract surgery was cancelled and the

FIG. 174. B-scan of mushrooming melanoma (arrow)

FIG. 175. A-scan of melanoma (vertical arrows)

patient referred to an ocular oncologist for management of the tumor.

There are a number of reports in the literature of unsuspected intraocular tumors that were not discovered until after cataract surgery. A study by Shields and Augsburger27 reviewed 21 cases of cataracts that had been removed in the presence of unsuspected choroidal or ciliary body melanomas. They stated, “Since ultrasonography has become readily accessible to most ophthalmologists in countries with advanced medical care, it should be considered as a part of the preoperative evaluation in all patients who have a cataract which is advanced enough to prevent a clear fundus view. It should definitely be performed in patients who have a dense unexplained unilateral cataract.” Peter et al. reviewed a series at the Armed Forces Institute of Pathology and found that 5.5% of

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enucleated eyes (35 of 650) for melanoma were aphakic or pseudophakic. They state, “we believe that most of these tumors were large enough at the time of cataract surgery to have been detected if diagnostic ultrasonography had been performed.”28 Shammas and Blodi29 state that “a considerable delay in diagnosis and treatment

Case Study 84. Choroidal Melanoma

of more than 10% of eyes containing advanced melanomas may result from an inability to visualize the tumor.” The possibility of such a potentially life-threatening lesion merits echographic imaging of an eye with a cataract or other media opacity that precludes adequate visualization of the posterior segment.

DH is a 72-year-old woman who underwent uncomplicated cataract surgery. The preoperative examination was felt adequate for visualization of all but the superior periphery of the fundus due to a cortical opacity in the upper half of the lens. Postoperative examination with the indirect ophthalmoscope detected a dark elevated lesion at 12:00 near the ora serrata.

Echography confirmed a solid, medium reflective lesion with mild spontaneous internal vascularity (Fig. 176). It was felt to be highly consistent with a malignant melanoma of the choroid and the patient was referred for radioactive plaque treatment. She was informed that there was a small chance that the surgical manipulation during cataract surgery had disseminated some tumor cells into her blood stream. She was referred to her primary care doctor for systemic evaluation.

A subgroup of patients with media opacities masking an unsuspected intraocular tumor is those with longstanding blind or nearly blind eyes with some degree of ocular discomfort. A study from the Armed Forces Institute of Pathology in 196329

found that 10% of blind painful eyes harbored malignant melanomas or other tumors. Char states that this percentage of malignancies in such eyes still holds true.30 Many of these eyes had experienced previous trauma or surgery. It is the standard of care in such an eye to perform diagnostic echography.

FIG. 176. A-scan of medium melanoma (vertical arrows)

GP is a 56-year-old man who presented with moderate corneal edema, anterior chamber reaction, and a cortical cataract. He gave a history of a lacerated globe by a piece of glass with immediate surgical repair a number of years previously. He had not seen well out of the eye since that time and the vision had gradually deteriorated to bare light perception over the past year. He felt a frequent aching pain in the eye and noticed that it looked red most of the time.

Echography was performed and demonstrated a solid, medium reflective lesion of the temporal ciliary body. It measured 5 mm in thickness and 10.2 mm in basal dimensions. Moderate spontaneous vascularity was noted (Fig. 177). The diagnosis of a ciliary body malignant melanoma was made and the eye was enucleated at the patient’s request.

Pathologic examination revealed an epitheloid melanoma of the ciliary body.

FIG. 177. A-scan of ciliary body melanoma (vertical arrows)

DW is a 67-year-old man with a 30+-year history of Coat’s disease in his right eye. He had undergone laser treatment years ago but had gradually lost the sight in the eye and it had become blind and painful with bullous keratopathy. He was scheduled for evisceration, but the surgeon ordered an ultrasound to eliminate any intraocular tumors.

Echography revealed an inferior dome-shaped mass measuring 3.63 × 6.04 × 8.76 mm on B-scan. A-scan demonstrated medium-to-low internal reflectivity (Fig. 178) with a medium angle kappa (sloping internal signals from higher to lower as the sound beam passed through the lesion). Spontaneous vascularity was not seen.

The surgeon was informed that the lesion was suspicious for melanoma and he changed the surgical plan from evisceration to enucleation because of the concern of possible dissemination of a malignant tumor. Pathology confirmed a spindle B melanoma.

A type of media opacity inherent to current cataract surgical techniques is opacification or wrinkling of the posterior lens capsule. After extra-capsular cataract surgery, the posterior capsule may become opacified and wrinkled over time. This occurs in 10% to 50% of cases and is usually treated by YAG laser capsulotomy. One of the potential complications of this procedure is retinal tear and detachment. This is a relatively rare occurrence, but young myopic males are reported to be of higher risk than other groups of patients. It is useful to know if a patient being considered for YAG capsulotomy has a preexisting PVD that would put him at lower risk for a retinal tear because of the absence of vitreoretinal traction.

FIG. 178. Top: B-scan of the lesion (arrow). Bottom: A-scan of choroidal melanoma (arrows)

CG is a 52-year-old man who had undergone cataract surgery in both eyes 2 years prior to presentation. Prior to intraocular lens implantation he was highly myopic with a refraction OD of −10.00 and OS of −9.50. He now complained of decreased vision in his right eye and visual acuity was measured at 20/70 in that eye and the left eye at 20/25. Slit-lamp examination showed moderate opacification of the posterior lens capsule in the right eye and slight opacification in the left eye. He was advised to undergo YAG laser capsulotomy on his right eye, but he seemed concerned about potential complications and asked a number of questions concerning the possibility of retinal detachment. His father had gone blind in one eye from a retinal detachment after cataract surgery.

The presence of a posterior vitreous detachment could not be verified on clinical examination because of the opacified posterior capsule. Echography was performed and demonstrated a total PVD (Fig. 179) with no evidence of vitreoretinal traction. He felt reassured that the possibility of a rhegmatogenous retinal detachment was minimal and proceeded with the laser procedure with resultant vision of 20/20 in that eye.

The existence of a PVD is also protective in patients with proliferative diabetic retinopathy. The neovascular scaffold that grows from the retina onto the posterior hyaloid face can undergo traction as the vitreous separates in a PVD and result in vitreous hemorrhage.

FIG. 179. B-scan of posterior vitreous detachment with Weiss ring (arrow)

EI is a 54-year-old woman with a 20-year history of type-1 diabetes. She had undergone panretinal photocoagulation in her right eye for proliferative retinopathy and scatter photocoagulation in her left eye for diabetic macular edema. She presented with a sudden loss of vision in her left eye which started as “seeing dots and streamers in my vision followed by almost total darkness.” Examination showed vision in her right eye of 20/30 and left eye finger count at 1 meter. The fundus of the left eye could not be visualized by the ophthalmoscope (direct or indirect).

Echography was performed and revealed a partial PVD with apparent focal traction on a neovascular scaffold on the optic disc (Fig. 180). This finding prompted a recommendation by her ophthalmologist to proceed with vitrectomy within the next several days instead of waiting 6 months for the hemorrhage to clear spontaneously. The concern was that of recurrent hemorrhage with the vitreousneovascular membrane traction that would reduce the chance of restoration of vision in that eye.

Media opacities, such as vitreous hemorrhage, can hide fundus lesions that are only detectable by echography. The sudden onset of flashes and floaters is often suggestive of a posterior vitreous

detachment and this is associated with a retinal tear from 6% to 15% of the time.31 This is usually detectable on indirect ophthalmoscopy but the presence of vitreous hemorrhage can preclude adequate visualization.

FIG. 180. B-scan of posterior vitreous detachment with traction on neovascular tuft (arrow)