Phthisis bulbi is the medical term for the end-stage of ocular globe atrophy that, in turn, may have been triggered by a variety of insults.
While patients at risk for PB may present with a wide variety of symptoms - those corresponding to the above mentioned possible triggers of ocular atrophy - PB itself is an end-stage condition pretty clearly defined.
An eye that underwent PB is of reduced size and diminished intraocular pressure. Due to its severity, the latter may be determined upon visual inspection. Ocular structures, including but not limited to a cornea, lens, and eyeball, may show edematous alterations, opacity, scars, and may be out of shape. They may lose their clearly defined borders.
Periorbital structures may show signs of inflammation.
Patients may claim the eye and periorbital tissues to cause pain.
As far as possible, an ophthalmologic examination should take place.
While the diagnosis of PB can readily be made upon visual inspection, the aim of the workup is to identify the cause of this condition. Due to a long time necessary for PB to develop, however, the trigger of the disease is usually known long before this end-stage is reached. Then, diagnostic measures should be undertaken to assess the current state of the underlying disease, e.g., to clarify if pathogens are still present or if neoplasms spread to adjacent tissues. To this end, histopathological analyses of biopsy samples may be helpful. Computed tomography scans allow for an evaluation of deeper structures. They usually depict calcifications and ossifications within the atrophied eyeball.
The condition of PB is irreversible. There is no chance to restore eyesight. However, supportive treatment may be offered to relieve, to treat infections or other persisting pathologies. Retrobulbar alcohol injection may be performed as an analgesic measure, systemic antibiotics are applied against bacterial infections. Other underlying diseases need to be adequately treated. It has to be noted that an eye that underwent PB frequently contains necrotic regions and may serve as a starting point for recurrent infection, inflammation and even malignant degeneration. In this context and possibly to resolve persistent pain, an enucleation should be considered.
An eye prosthesis may be inserted in order to restore the shape of the eyeball for aesthetic reasons .
Prognosis for a restoration of eyesight is hopeless. Also, the prognosis for a preservation of the eyeball is poor. An enucleation may be the only way to stop pain; it may also be realized as a preventive measure to avoid relapses of inflammation and possibly malignant degeneration. However, if stable and non-painful, an enucleation may not be necessary and the prosthesis may be inserted above the remaining eye  .
Virtually any ophthalmologic disease may result in PB, but if adequate treatment is provided in a timely manner, most of them are curable. However, even a slight corneal ulceration may progress if left untreated. Pathogens may spread to adjacent tissues, cause infection and inflammation of deeper ocular structures and eventually lead to PB.
Most frequently, infection and inflammation, e.g., keratitis, uveitis, and panophthalmitis, as well as trauma account for this condition . Of note, panophthalmitis typically develops as a consequence of septicemia or trauma. Here, "trauma" may be understood in the broader sense of the word and include surgical interventions, particularly those to treat cataracts. Retinal detachment is not uncommon in myopic patients or those that underwent cataract surgery and may initiate the process of eyeball atrophy. Exposure to radiation, heavy light, and ocular or periorbital neoplasms may also severely damage the eye and trigger PB.
With regards to tumors, retinoblastoma is among the most common ocular neoplasms. Retinoblastoma is a malignant neoplasia usually diagnosed in pediatric patients. There are other conditions more frequently encountered in children that may be associated with PB. Children may suffer from congenital syphilis and the late form of the disease may cause keratitis, uveitis, optic atrophy and PB . Measles, for instance, a viral disease typically contracted by children, may be associated with corneal ulcerations. As has been mentioned above, this disease may progress aggressively if not adequately treated. In children suffering from vitamin A deficiency, these corneal ulcers may result in keratomalacia and PB . Furthermore, children are more prone to traumatic eye injuries. These become easily infected, may be related to infection and inflammation of determined ocular structures or even panophthalmitis. If children need to undergo keratoplasty and vitrectomy, possibly after sustaining ocular trauma, there is a high risk for PB . Rarely, developmental anomalies like persistent hyperplastic primary vitreous may cause PB. They may also make eye surgery necessary and these surgical interventions again increase the risk for PB. Such anomalies may, for instance, be associated with Patau syndrome or Norrie disease .
There are some retrospective studies regarding ophthalmologic diseases leading to enucleation. In general, a decrease in the overall number of enucleations has been observed  . This may be explained by improved diagnostic and therapeutic measures that allow for the preservation of eyes that could not have been saved decades ago. Also, changes regarding the most common causes of enucleation have been ascertained. In this line, glaucoma often lead to enucleation at the middle of the 20th century, but glaucoma therapy significantly improved and enucleation is rarely necessary today. PB, however, is still among the three most frequent diagnoses leading to enucleation . Of note, the remaining two are trauma and endophthalmitis, which, in turn, may result from trauma or septicemia.
A more specific study was conducted regarding PB in uveitis patients . About one out of five patients suffering from severe visual loss due to uveitis also showed signs of PB. Interestingly, almost half of these patients also suffered from visual impairment in the other eye, an observation that may indicate systemic disorders or sympathetic ophthalmia. In this study, a mean age of onset of 54 years was calculated for PB patients. Men were affected slightly more often than women.
The pathophysiological process behind PB is an overall reduction of aqueous humor, an inviscid fluid secreted by the ciliary epithelium that fills the anterior and posterior chambers of the eyes. One of its main functions is to maintain the intraocular pressure of the eye. A tightly regulated balance of aqueous humor production and drainage, notably via Schlemm's canal and uveal vessels, is necessary to keep this pressure in its physiological range. Values between 10 and 20 mm Hg are considered physiological. The aqueous humor also serves as a transport medium for nutrients that may thus reach those ocular structures that don't dispose of blood perfusion.
Since a wide variety of ophthalmologic and systemic diseases may eventually lead to PB, the initial appearance of the eye may be very different from that observed in the end-stage. For instance, there is a close relation between uveitis and glaucoma, and the latter may cause a hydrophthalmos, i.e., an enlarged eye due to increased intraocular pressure. This is precisely the opposite of PB: Here, the intraocular pressure decreases to 0 mm Hg.
Long before reaching that extreme, the cornea loses its tone and suffers from a nutrient deficiency. A corneal edema develops, the cornea becomes opaque. Furthermore, a thickened sclera is characteristic for PB. Another ocular structure depending on glucose and amino acids provided by the aqueous humor is the lens and consequently, PB is associated with cataracts. Cyclitic membranes may be detected. Lesions of structures located in the ocular fundus can also be observed. The head of the optic nerve and the macula develop edema, retinal atrophy becomes evident. Retinal detachment and proliferative vitreoretinopathy may follow. Pathological processes finally compromise all ocular structures and a generalized atrophy takes place.
Between the initial insult and PB, years may pass. In one study, a mean period of almost three years was reported for a development of PB . Patients suffering from ocular atrophy due to infection or trauma are often diagnosed with PB before two years have passed; uveitis patients, in contrast, often take more than six years to reach this stage.
Histopathological analyses of enucleated eyes have shown extensive pathologic tissue alterations comprising necrosis, dystrophic calcification, osseous metaplasia and gliosis to have occurred in eyes undergoing PB.
Early detection of ophthalmologic diseases and adequate therapy of ocular lesions in a timely manner may help to avoid PB. Spreading infections should be aggressively treated. Any condition leading to intraocular hypotony, e.g., excess cyclodestruction in the scope of glaucoma therapy, should be avoided.
In advanced stages of ophthalmologic diseases, surgical interventions may still delay PB. In this context, keratoprosthesis surgery may contribute to improving vision through anterior ocular structures. Also, chronic cyclodialysis, as well as cyclitic membranes, may be remedied surgically .
In general, any protective measures that reduce the incidence of insults to the eye may also be considered prevention of PB.
Phthisis bulbi (PB) refers to the condition of well-advanced atrophy of the eyeball, the bulbus oculi. It is a descriptive term that doesn't provide any information to its possible causes. Infection, inflammation, and trauma are the most common triggers for ocular atrophy, but it may also arise as a complication of eye surgery, particularly of surgical interventions to treat cataracts . Other, possible causes of PB are excess exposure to light or radiation and compression by space-occupying processes in close proximity, e.g., by neoplasms of the periorbital region.
Over the course of the underlying disease, the volume of aqueous humor is progressively diminishing - this process may occur in rather short or long time frames, depending on the specific pathology - and the eyeball adopts a soft structure. Since one of the main functions of the aqueous humor is to maintain the intraocular pressure and to keep different ocular structures at their physiological position, its reduction severely compromises the surrounding ocular tissues. The end stage of these pathophysiological events is an atrophied ocular globe designated as PB. This condition is characterized by a shrunken eyeball that only in rare cases confers partial vision. Most PB patients are blind in the affected eye.
PB is an irreversible condition. There is no therapy. However, the underlying disease should be determined and treated accordingly in order to avoid further tissue damage. If the patient suffers from pain, an enucleation may be indicated. Other symptoms may be treated symptomatically. Also, the abnormal, even scary appearance of the eye may be associated with social problems and the insertion of an ocular prosthesis may significantly improve that aspect of the disease. Prosthesis insertion may or may not be preceded by enucleation of the remaining ocular globe  .
Phthisis bulbi (PB) is the medical term for the end-stage condition of a shrunken eye. Here, phthisis means wasting and bulbi refers to the ocular globe.
Any severe eye disease may result in PB. Even seemingly harmless lesions to the cornea may spread to underlying tissues and finally affect the whole eyeball. Infection and inflammation are indeed the most frequent triggers of PB. Another common cause of this condition are traumatic insults. Tumors growing within or in close proximity to the eye as well as developmental defects may provoke PB.
Furthermore, systemic diseases associated with septicemia, e.g., spread of pathogens throughout the body within the bloodstream, may affect the eye and lead to PB.
An eye that underwent PB is reduced in size and appears softer because it lost its intraocular pressure. Patients may note considerable opacity in all visible eye structures. There may also be signs of inflammation and these are not necessarily limited to the interior of the orbit. Some patients experience pain.
PB is diagnosed upon visual inspection. However, biopsy samples may need to be obtained for histopathological analyses and assessment of the current condition of intraocular tissues, e.g., to clarify if an infection is still present. In order to evaluate deeper structures, computed tomography scans may be carried out.
Treatment is supportive and aims at pain relieve and prevention or therapy of infection and inflammation. The dead tissue within the atrophied eye may serve as a starting point for recurrent infection and it may thus be recommendable to remove it surgically. This procedure is called enucleation.
Eye prosthesis may help to restore the shape of the eye once the underlying tissues are healed.