The phthisical eye, also known as phthisis bulbi, represents a severe, end-stage condition of the eye. It is characterized by the irreversible shrinkage and disorganization of the entire eyeball, often leading to complete blindness in the affected eye. This condition is a final response to severe damage or disease within the eye.
Understanding Phthisical Eye
A phthisical eye exhibits distinct physical characteristics. The globe is noticeably shrunken, often appearing half to a third of its normal size, and can have a squared-off shape. It has a soft texture upon palpation, a condition known as hypotony, due to extremely low intraocular pressure.
The internal structures are severely disorganized and atrophied, making it difficult to identify individual components like the lens or retina. The cornea, normally clear, often becomes opaque and thickened. The sclera, the white outer layer of the eye, also thickens, and there can be scarring and disorganization of intraocular tissues due to fibrosis.
Microscopic examination reveals inflammatory reactions and cell proliferation. Calcium deposits and bone formation, known as osseous metaplasia or “intraocular bone,” are common. The retina and choroid are frequently detached, often due to the formation of membranes within the eye.
Factors Leading to Phthisical Eye
Phthisical eye develops from various severe ocular insults. One significant cause is severe ocular trauma, including penetrating injuries or burns, which can initiate a cascade of events leading to disorganization and atrophy. Such injuries can profoundly disrupt the eye’s delicate internal environment.
Chronic inflammation, particularly uveitis, is another common pathway. Prolonged inflammation can lead to cyclitic membranes, which pull on internal structures and cause hypotony. Advanced stages of inflammatory diseases, such as juvenile idiopathic arthritis or Behçet disease, are associated with this outcome.
Complicated eye surgeries can sometimes lead to phthisis, especially procedures involving significant intraocular manipulation or infection. Examples include complex retinal detachment surgeries with proliferative vitreoretinopathy or procedures leading to suprachoroidal hemorrhage. Advanced stages of glaucoma, a condition characterized by high intraocular pressure, can eventually lead to a shrunken, non-functional eye.
Severe retinal detachment that remains untreated or unsuccessfully managed can also progress to this condition, as the retina’s separation from its blood supply causes tissue degeneration. Certain infections within the eye, if severe and prolonged, contribute to damage culminating in a phthisical eye.
Approaches to Management
Managing a phthisical eye primarily focuses on addressing symptoms and cosmetic concerns, as visual potential is typically absent. Medical management often involves alleviating pain and discomfort, which can arise from chronic irritation or inflammation within the shrunken globe. This may include topical or systemic medications to manage inflammatory processes.
For cosmetic improvement, non-surgical and surgical options are available. Scleral shells are custom-fitted prostheses that fit over the shrunken eye, providing a more natural appearance without removing the existing globe. When the phthisical eye is significantly disfigured or causes persistent pain, a prosthetic eye offers a more complete cosmetic solution. This often involves a surgical procedure to prepare the orbit.
Surgical intervention is considered for severe cases, particularly when pain is unmanageable or for significant cosmetic improvement. Enucleation involves complete removal of the eyeball, leaving surrounding orbital tissues intact. After enucleation, an orbital implant is placed to maintain volume, followed by fitting a prosthetic eye. Evisceration, an alternative, involves removing the internal contents of the eye while preserving the scleral shell and eye muscles. This approach offers more natural movement of the prosthetic eye as muscles remain attached to the preserved scleral shell.