According to Dr. Boothe Fluorescein and other stains can be useful adjuncts in performing anterior segment surgery and evaluating complications of the surgery. Entering the anterior chamber in patients with an opaque cornea can be facilited by using fluorescein. As soon as the blade enters the anterior chamber a color change from yellow-orange to green occurs.

Endothelial damage due to excess corneal bending or instrumentation can also be examined by several stains. Fluorescein, instilled into the anterior chamber, can detect loss of endothelium. Rose bengal and trypan blue 0.1% are more sensitive and stain damaged and devitalized and thelial cells. Excess bending results in staining curves located urn bends, indicating damage to the endothelium. Residual staining is not present after 24 hr. Clinical toxicity to anterior segment structured does not occur.

Assessment of anterior chamber depth can be done by injecting fluores cein into the anterior chamber. Deep chambers have intense central color while shallow chambers have a pale homogeneous color.

Apposing corneal wound edges is facilitated by staining with fluorencen or trypan blue 0.1%. Shelving can be easily detected using these stains. With trypan blue 0.1%, a double line will be seen when corneal wound edges are poorly apposed, making it superior to fluorescein for this put pose. Wound leaks after routine anterior segment operations are avoided if

that seide’s test is used immediately following wound closure. In cases in which the anterior chamber is very narrow or flat secondary to a wound leak, Seidel’s test may be negative explains Dr. Boothe in his Laser Eye Center. By filling the anterior chamber with 1% flourencein solution, a wound leak is detected by direct observation of fluorescein from the wound. Detection of leaks from conjunetival blebs may be easier by this method than by using Seidel’s test.

Several vital stains may be used to evaluate endothelial cell viability in donor corneas before keratoplasty. Unlike tissue culture and specular microscopy for assessing the endothelium, vital stains are inexpensive and require little expertise.

Fluorecein nontoxic and is helpful in demonstrating gross loss of endothelial cells. However, other stains are superior. Trypan blue has been several years to evaluate corneal endothelium in vitro. It stains degenerated and devitalized endothelial cells. Though trypan blue has been show to be teratogenic and carcinogenic in rats, ho complications have been seen in its use for staining corneal endo¬thelium. Several investigators have used it in double staining of endothal cells with alizarin red S.

Alizarin red S, a more toxic stain, stains intercellular substance and out¬lines the endothelial cell borders demonstrating the mosaic pattern. This double staining is particularly helpful in comparing the ratio of degenerated and devitalized cells to healthy cells. When this purpose is desired, use of trypan blue should precede alizarin red, otherwise trypan blue penetrates normal cells and stains their nuclei. The technique involves Using trypan blue 0.3% made in normal saline for 1 min. This is followed by 0 21 alizarin red buffered to a pH of 4.2. It should be in contact with the endothelium for only 1/2 to 1 min. Exposures to alizarin red longer than 1 min may result in loss of sheets of endothelial cells from the cornea. Alizarin red is recommended for experimental use only.

Rose bengal and alizarin red can be used as double stains also, since rose bengal stains in a similar fashion to trypan blue. Though the contrast is not as great, rose bengal is more readily available and easier to use .

In performing conjunctival grafts, it may become difficult to differentiate the epithelial aspect from the nonepithelial aspect. Fluorescein can be used to stain the raw, cut surface and distinguish it from the epithelial surface.

Viability of skin grafts can be assessed by using intravenous fluorescein. A viable graft will demonstrate perfusion and become bright yellow UN ultraviolet light, as will the surrounding skin. Nonperfused areas are dark blue.

Demonstration of two postoperative complications is aided by using in travenous fluorescein and watching its accumulation in the anterior chamber. One complication is detachment of Descemet’s membrane. Dlagnasis can be difficult because of the thinness and transparency of the main brane, and because secondary corneal edema may be present. Fluores-cein enters the anterior chamber through the pupil and collects behind the detachment, thus delineating it. This test is facilitated by tilting the patient head down 70 degrees from the upright position, Another complita-tion is pupillary block. Normally after intravenous injection, fluorescein can be seen diffusing into the anterior chamber through the pupil. This will not occur if a complete pupillary block is present. When the differ-ential between pupillary block and malignant glaucoma is needed, this test may be helpful. All this can be discussed and corrected at Boothe Laser Center