[Echographic differential diagnosis of optic nerve widening]. / Echographische Differenzialdiagnose von Optikusverbreiterungen.

INTRODUCTION: Standardized echography is a well-established examination technique in ophthalmology. Among other things one of the more important uses is the evaluation of the optic nerve and its abnormalities. One aspect is the use of the stretch-test (originally called the "30 degrees-test") for the differential diagnosis of optic nerve widening. Such widening can be caused by solid thickening of the optic nerve and/or its sheaths or by solid infiltration of the subarachnoidal space. More frequent is a widening of the optic nerve as a consequence of sheath distension by increased subarachnoidal fluid. PATIENTS AND METHODS: We present various cases of widened optic nerve patterns and explain the technique and diagnostic value of standardized echography, especially of the stretch-test. RESULTS: In widened optic nerve patterns due to fluid around the optic nerve parenchyma, a decreased optic nerve thickness will be found when performing the stretch-test (positive test result), whereas in solid lesions of the optic nerve no change of optic nerve thickness will be seen (negative test result). CONCLUSION: The stretch-test provides a reliable tool for the differential diagnosis of widened optic nerves.

Choroidal ganglion cell plexus and retinal vasculature in monkeys with laser-induced glaucoma.

The choroid of primates possesses an elaborate nitrergic nerve fiber plexus containing a great number of ganglion cells. Postganglionic nerve fibers innervate mainly the choroidal vasculature. In addition, the choroid contains an elastic muscular system closely associated to the vasculature. The goal of the present investigation was to analyze how sustained IOP elevation would affect the choroidal vasculature with its specialized innervation and the adjacent retina. For this purpose the posterior eye segment of 15 rhesus monkeys which after laser coagulation of the trabecular meshwork developed elevated IOP up to 4 years were studied using immunohistochemical and histochemical methods, and scanning electron microscopy of corrosion casts. The most striking finding was a significant reduction of choroidal thickness and loss of choroidal ganglion cells and nerve fibers, especially in the central portion of the choroid. Corrosion casts of the choroidal vasculature showed a slight decrease in capillary density and a decrease in length of the arterioles in glaucomatous eyes. Whole mount preparations of the retina stained for NADPH diaphorase revealed a significant reduction in positively stained amacrine cells, reduction in diameter of arterioles and changes in the staining pattern of the retinal vasculature, particularly in the perimacular region.

A study of aqueous humor dynamics in keratoconus.

Clinical observations suggest that patients with keratoconus have lower intraocular pressures, on average, than normal subjects. Our purpose was to determine whether differences in aqueous production and outflow facility could account for differences in intraocular pressure between a group of patients with keratoconus and a group of normal, age-matched control subjects. Aqueous humor dynamics were determined by the use of fluorophotometry in one eye of seven patients with keratoconus and ten age-matched normal subjects. Intraocular pressure was measured by applanation tonometry. Keratoconus patients had a statistically significant lower mean intraocular pressure than normal control subjects (11.3 +/- 1.6 mmHg vs. 16.6 +/- 2.8 mmHg, P = 0.0004). The difference in mean intraocular pressure remained significant even after correcting for possible errors in applanation tonometry due to thin corneal stroma. There was no difference in mean aqueous humor flow rates in the keratoconus patients as compared to controls (2.29 +/- 0.53 microliter min-1, P = 0.73). The mean apparent outflow facility was 0.21 +/- 0.07 microliter min-1 mmHg-1 for keratoconus patients compared to 0.14 +/- 0.03 microliter min-1 for controls (P = 0.02). Lower mean intraocular pressure in keratoconus patients appears to be due to increased outflow facility as compared to normal subjects.

Optic nerve compression from a basal encephalocele.

A woman developed headaches, transient visual obscurations, anosmia, and decreased visual acuity. Ocular examination showed bilateral pulsatile proptosis and disc edema with choroidal folds. Standardized ophthalmic echography showed absence of bony orbital roofs, prominent dural pulsations, direct apposition of brain parenchyma and orbital tissues, and echographic signs suggesting bilateral optic nerve compression. CT and MRI showed a large defect in the floor of the anterior cranial fossa. The cribriform plate, both orbital roofs, and sphenoid bones were displaced by a large basal encephalocele. Clinical improvement followed reconstruction of the anterior cranial fossa and decompression of both optic nerves.

Ophthalmic features of Alagille syndrome (arteriohepatic dysplasia).

Eight patients with Alagille syndrome (AGS) are reported. In addition to previously reported findings of posterior embryotoxon, pigmentary retinopathy, and choroidal folds, new findings include decreased axial eye lengths, small corneal diameters, and shallow anterior chambers. Optic disc swelling was noted ophthalmoscopically and abnormally increased orbital subarachnoidal fluid was detected through measurements of the arachnoidal diameters with standardized echography.

Acute promyelocytic infiltration of the optic nerve treated by oral trans-retinoic acid.

BACKGROUND: Oral trans-retinoic acid has recently been shown to be an effective treatment modality for acute promyelocytic leukemia. This type of drug differs from traditional tumoricidal agents by promoting differentiation of the malignant, immature cells. METHODS: The authors describe a patient with optic nerve infiltration by acute promyelocytic leukemia documented ophthalmoscopically and confirmed by standardized echography and magnetic resonance imaging. High-resolution chromosome banding revealed the patient had a 15;17 chromosomal translocation known to be associated with acute promyelocytic leukemia. Treatment was instituted with oral all trans-retinoic acid without adjuvant radiotherapy or intrathecal chemotherapy. RESULTS: Results of serial bone marrow examination showed progressive differentiation of malignant cells with complete bone marrow remission. Results of serial ophthalmic examinations showed complete resolution of the leukemic optic nerve head infiltration. CONCLUSION: All trans-retinoic acid alone can be an effective treatment for optic nerve head infiltration in acute promyelocytic leukemia. This case suggests that radiation therapy may not be necessary in acute promyelocytic leukemia with optic nerve infiltration.

Maternal orbital hematoma associated with labor.

We examined two women with orbital hematomas that occurred during labor. Both women developed sudden diplopia, proptosis, and orbital pain. The location of the hematoma was confirmed by orbital echography and computed tomography. The patients were observed without surgical intervention. Neither patient developed clinical or echographic signs of compressive optic neuropathy. Clinical resolution occurred during the following two weeks. Serial standardized orbital echographic examinations documented resolution of the hematomas.

Terson's syndrome. Clinicopathologic correlations.

In seven cases of Terson's syndrome, an elevated, dome-shaped, membrane was detected in the posterior pole by ophthalmoscopy, echography, or during pars plana vitrectomy. Light and electron microscopic examination of two additional eyes obtained postmortem from an acute case of Terson's syndrome revealed that the posterior vitreous face was elevated by blood and that the internal limiting membrane of the retina was intact and in its normal position. In two chronic cases, a dome-shaped epiretinal membrane was excised from the macula during vitrectomy. Light and ultrastructural studies demonstrated that the membranes consisted of glial cells and basement membrane material. The dome-shaped structure observed in eyes with Terson's syndrome is due to the formation of a subhyaloid hemorrhage. The partially detached posterior hyaloid face created by this hemorrhage provides a scaffold for cellular proliferation and the development of an elevated epiretinal membrane in long-standing cases. Echographically, this membrane resembles a retinal detachment in B-scans, but can be clearly distinguished from retina with standardized A-scan.

Standardized echographic-histopathologic correlations in liposarcoma.

A 57-year-old woman had metastatic liposarcoma of the left orbit that underwent transformation. The primary focus in the abdomen, resected in 1975, was a well-differentiated liposarcoma. Later metastases to the neck and orbit were poorly differentiated, pleomorphic, and highly anaplastic liposarcomas. The ultrasonographic and histopathologic correlations of the different stages of the tumor during the disease process were analyzed and compared. This patient's disease had echopathologic similarities to other orbital sarcomas and adult cavernous hemangiomas.

Trochleitis with superior oblique myositis.

Thirteen patients complained of recent fluctuating aching of one orbit, punctuated by stabbing pains. All had exquisite point tenderness over the trochlea and in half of the patients the pain was aggravated by eye movement. Standardized A-scan echography demonstrated swelling of the peritrochlear tissue and thickening of the superior oblique muscle with low internal acoustic reflectivity, typical of myositis. CT scan showed a soft tissue density in the region of the trochlea. Biopsy, performed on two patients, revealed peri-trochlear inflammation. In all patients the symptoms resolved within a period of weeks or months: indomethacin or naproxen were not effective, but oral or locally injected corticosteroids shortened the course compared to no treatment. None of the patients had ptosis, proptosis, Brown's syndrome, or a click, nor did they have echographic or radiographic signs of sinusitis or inflammation away from the trochlea. This probably represents a highly localized subtype of idiopathic orbital inflammation ("pseudotumor").

Echographic detection and classification of posterior hyphemas.

A 'posterior hyphema' (in analogy to the classic hyphema seen in the anterior chamber) is a collection of liquid blood at the bottom of a fluid-filled space in the posterior segment of the eye. The horizontal surface of a posterior hyphema produces strong signals echographically which, at first glance, may be confused with signals from a retinal detachment or a preretinal membrane. With the patient being examined in a supine position, a retinal detachment of the inferior posterior fundus involving the macula is suggested. Such a misdiagnosis would have serious consequences for the management of a patient and must be avoided. A simple, quick and effective (both highly sensitive and specific) echographic (A-scan and B-scan) shift technique clearly differentiates a posterior hyphema from a retinal detachment and a preretinal membrane. This shift method has been applied successfully in 62 consecutive cases of posterior hyphema. These represent 20% of 304 cases with severe posterior segment hemorrhages examined echographically in a 3-year period. With echography, the height of a posterior hyphema can be measured precisely and its consistency ranging from very liquid ('thin' hyphemas) to highly viscous ('thick' and 'sticky' hyphemas) can be determined. Thus, echography contributes important information about this special kind of posterior segment hemorrhage, particularly useful in previtrectomy evaluations.

Metastatic carcinoid unresponsive to radiation therapy presenting as a lacrimal fossa mass.

A case of metastatic carcinoid tumor presenting as a lacrimal fossa mass is described. This appears to be only the fourth case report of metastatic carcinoid to the orbit and the first to include ultrasound evaluation. the tumor mass did not regress despite radiation therapy as documented on serial ultrasound examinations. Therapeutic implications of this finding are discussed. Metastatic carcinoid tumors are reviewed.

The diagnosis and prognosis of atypical carotid-cavernous fistula (red-eyed shunt syndrome).

Nineteen patients who complained of red eyes had the characteristic clinical signs of an atypical carotid-cavernous fistula. Episcleral veins were dilated, intraocular pressure and episcleral venous pressure were high, and blood filled Schlemm's canal during gonioscopy. Most of the patients had mild exophthalmos, but in none was the exophthalmos obviously pulsatile, and in only two patients could a bruit be heard. Orbital echography disclosed either a dilated superior ophthalmic vein or congestion of the orbital soft tissues. Selective carotid angiography, done in seven patients, disclosed the fistula to be a dural-cavernous fistula. The serious complication of the fistulas was open-angle glaucoma resulting from the high episcleral venous pressure. None of the fistulas was treated surgically, but six closed spontaneously and three closed soon after carotid angiography.

[A new echographic sign for the reliable diagnosis of graves' disease (author's transl)]. / Ein neues echographisches Merkmal zur verhässlichen Differentialdiagnostik des endokrinen Exophthalmus.

With standardized echography, an ultrasonic method specifically designed for tissue differentiation, Graves' orbitopathy can be diagnosed reliably and accurately even when the clinical picture and thyroid tests are not typical for this condition (e.g., with unilateral exophthalmus, lack of lid signs, euthyroid status). A new echographic criterion of Graves' orbitopathy, i.e., the heterogeneous and high-reflective structure of the diseased muscle tissue, plays a key role in the differential diagnosis.