Ultrasound biomicroscopy in the assessment of anterior scleral disease.

High-frequency ultrasound biomicroscopy is a new method of examining subsurface anterior segment structures of the eye at microscopic resolution. The sclera has a high internal reflectivity and can be differentiated from the cornea, and overlying and underlying tissue. Using this modality, we examined 18 patients with various manifestations of scleral disease. Localized anterior staphyloma could be differentiated from other causes of a black spot on the scleral surface. Episcleral thickening could be differentiated from involvement of the sclera itself. Different patterns of scleral involvement could be imaged including diffuse low-reflective mottling, low-reflective nodules extending into the scleral substance, and scleral thinning. Scleral thinning could be assessed and quantified. Underlying changes in the vitreous could be detected. Ultrasound biomicroscopy was a useful adjunct to clinical examination in the assessment of anterior scleral disease.

Orbitotonography, the dynamic assessment of orbital tension: 2. Results in patients with orbital disease.

Dynamic orbitotonography was done in 17 patients with Graves' disease, 25 patients with orbital tumours and 15 healthy subjects. The mean orbital pressure for both patient groups was significantly different from that for the healthy subjects at each time interval (p less than 0.001). Healthy patients may be differentiated from those with orbital disease with a good degree of reliability with this technique. As well, the technique may provide information about the location of disease within the orbit.

The role of sophisticated radiological testing in the assessment and management of epiphora.

In the management of a patient with epiphora, appropriate investigation is important in arriving at the cause of obstruction, and in helping to outline a plan for management. Standard dacryocystography has been modified by utilizing the techniques of intubation, distension, macrography, and subtraction to produce optimal anatomical information. Lacrimal nuclear scanning with the addition of rapid sequence display and computer interfacings produce the most sophisticated functional information regarding tear drainage. The role of plain films and computerized tomography in lacrimal drainage pathway disease is outlined.

The pattern and incidence of nasolacrimal injury in naso-orbital-ethmoid fractures: the role of delayed assessment and dacryocystorhinostomy.

A detailed review of forty-six patients with severe naso-orbital-ethmoid injury confirms that naso-lacrimal system injury is less common than originally suspected. Post-operative epiphora is more frequently due to eyelid malposition than naso-lacrimal obstruction. Eight patients (17.4%) required eventual dacryocystorhinostomy. Three out of five patients (60%), treated with closed reduction and external splint fixation, needed dacryocystorhinostomy. This treatment predisposes to external compression of the naso-lacrimal system by malpositioned bone fragments and segments. Open reduction and internal fixation of all fractures provides optimal repair and minimizes the incidence of post-operative epiphora. During fracture repair, the naso-lacrimal sac should be identified, but not probed or intubated unless obviously lacerated. The upper lacrimal pathway is protected by the medial canthal ligament. Obstruction usually occurs in the bony naso-lacrimal canal. Telecanthus invariably accompanies severe naso-orbital-ethmoid injuries and subsequent naso-lacrimal obstruction. Dacryocystography is useful in the investigation of naso-lacrimal function. When dacryocystorhinostomy is necessary, it should be performed at least 3 months after the primary repair.

Orbitotonography, the dynamic assessment of orbital tension: 1. Results in subjects without known orbital disease.

This paper describes a new orbitotonometer and method of dynamically assessing the orbital tissue resistance ("orbital tension"). In 20 healthy volunteers without known orbital disease the inexpensive instrument proved to be safe and accurate, providing useful, reproducible clinical information. The full diagnostic work-up of patients with orbital disease should include the accurate measurement of orbital tension, as this may provide the ophthalmologist with earlier objective evidence of the disease process as well as a method of following its course.

Toxicity of the chemiluminescent material Cyalume in anatomic assessment of the nasolacrimal system.

One of the most intriguing recent ideas for anatomic assessment of the nasolacrimal system is the use of chemiluminescence, whereby the entire system can be made visible in the physician's office. The potential toxicity of the chemiluminescent material Cyalume was evaluated through a clinical and pathological study of 34 rabbit eyes exposed ot it in various ways. When Cyalume was sealed in the nasolacrimal system, simulating clinical blockage, there were no toxic effects, even after 30 to 40 days, and only minimal side effects occurred with similarly prolonged subcutaneous exposure to the material. However, subtarsorrhaphic, subconjunctival and intra-aqueous deposits had caused serious complications in high proportions of eyes after 30 to 40 days. Similar toxic effects occurred, though, in all control eyes treated with Ethiodan (iophendylate), a contrast medium commonly and safely used in dacryocystography, which was injected either subconjunctivally or into the anterior chamber. Thus, Cyalume should have minimal toxicity when used clinically in the proposed fashion, provided extravasation of the material is carefully avoided.

Inflammation of the lacrimal drainage system--assessment by thermography.

Thermography is an investigative tool without side effects. To our knowledge thermography has not been evaluated in the assessment of lacrimal passage inflammation and obstruction. It can give an objective assessment of presence and degree of inflammation. An infrared scanning device was used to detect surface temperatures in 29 patients with known disorders of the lacrimal drainage passage. Thermal images were compared for bilateral symmetry and against the normal thermographic appearance of the face. Acute dacryocystitis and canaliculitis showed gross hyperthermia and asymmetry. Forty-two percent of patients with a picture of chronic dacryocystitis and 40% of patients with only tearing and no clinical evidence of inflammation showed temperature elevation on the side of involvement, whereas 58% and 60% of these respective groups showed symmetrical thermal patterns, suggesting no active inflammation. In a few cases there were discrepancies between clinical assessment and objective thermographic evaluation of the degree of inflammation. The implications of our results and possible applications of thermography are discussed.

Assessment of the efficacy of chemiluminescent evaluation of the human lacrimal drainage system.

A chemiluminescent material, Cyalume, was used to demonstrate the anatomy and patency of the human lacrimal drainage system. Cadaver models were used to simulate blockages at various levels of the lacrimal drainage system and the Cyalume technique compared favorably with the corresponding dacryocystograms. Cyalume also shows promise for use in locating the lacrimal sac at surgery, the proximal end of a lacerated canaliculus, and the free ends of canalicular intubation tubes high in the nose. The authors feel that Cyalume shows promise as both a convenient method of clinical investigation of the lacrimal system and an aid in lacrimal surgery.

Intubation macrodacryocystography and quantitative scintillography: the "complete" lacrimal assessment.

Intubation MDCG with subtraction provides excellent visualization of the lacrimal excretory apparatus. Quantitative lacrimal scintillography is the most useful method of assessing lacrimal excretory function. These two investigations are complementary and may be performed simultaneously. They provide a rational basis for diagnosis and management of disease of the lacrimal drainage system.