Enucleation

Enucleation is the surgical removal of the entire globe (eyeball) along with the intraorbital portion of the optic nerve, while preserving the extraocular muscles, orbital fascia, and eyelid margins. This procedure is indicated for end-stage ocular diseases that are blind, painful, and unresponsive to medical or surgical therapy, or for conditions where the globe is a source of severe systemic disease, such as intraocular neoplasia with potential for metastasis. Enucleation is distinguished from exenteration, which removes the globe plus all orbital contents including extraocular muscles, fascia, and often eyelids, and from evisceration, which removes intraocular contents while leaving the scleral shell and extraocular muscles intact. The goal of enucleation is to eliminate pain, remove a diseased or traumatized eye, and achieve a cosmetically acceptable result, often with the placement of an orbital implant to maintain orbital volume and support the overlying tissues. The procedure requires meticulous surgical technique to ensure complete removal of all intraocular and optic nerve tissue, prevent hemorrhage, and minimize postoperative complications such as orbital infection, implant extrusion, or sinking of the orbital prosthesis.

Enucleation is performed for a wide range of ocular and orbital conditions. Primary indications include: (1) Severe ocular trauma with irreparable damage to the globe, such as rupture, extensive lacerations, or penetrating injuries that result in loss of intraocular contents and irreversible blindness; (2) End-stage glaucoma with persistent pain and blindness unresponsive to medical or surgical management, often associated with buphthalmos, corneal ulceration, or lens luxation; (3) Intraocular neoplasia, including uveal melanoma, ciliary body adenoma/carcinoma, medulloepithelioma, and metastatic tumors, where enucleation is curative or palliative; (4) Severe, chronic uveitis or panophthalmitis that is refractory to therapy and results in phthisis bulbi or severe pain; (5) Orbital cellulitis or abscess that threatens the globe and optic nerve, where enucleation may be necessary to control infection; (6) Congenital anomalies such as microphthalmos, anophthalmos, or severe orbital malformations that are nonfunctional and painful; (7) Prolapse of the globe (proptosis) with severe damage to the optic nerve or extraocular muscles, where replacement is not feasible; (8) Fungal or parasitic infections of the globe, such as cryptococcosis or dirofilariasis, that are unresponsive to medical therapy; (9) Severe corneal perforation with iris prolapse and loss of anterior chamber integrity; (10) Iatrogenic causes, such as failed intraocular surgery leading to phthisis or chronic pain. The underlying etiology dictates the urgency and specific surgical approach, with neoplastic and infectious conditions requiring careful handling to prevent dissemination.

Enucleation is a common surgical procedure in veterinary ophthalmology, performed in both dogs and cats, with no significant sex predilection. The incidence varies with the underlying disease. In dogs, the most common indications are glaucoma (approximately 40-50% of cases), followed by trauma (20-30%), and intraocular neoplasia (10-20%). Primary glaucoma is particularly prevalent in breeds such as American Cocker Spaniels, Basset Hounds, Chow Chows, Shar-Peis, and Boston Terriers, with a hereditary basis. Secondary glaucoma due to lens luxation is common in Terrier breeds (e.g., Jack Russell Terrier, Tibetan Terrier). Intraocular melanoma is the most common primary intraocular tumor in dogs, with a higher incidence in Labrador Retrievers, Golden Retrievers, and German Shepherd Dogs. In cats, chronic uveitis and associated secondary glaucoma are leading causes, often linked to feline leukemia virus (FeLV) or feline immunodeficiency virus (FIV) infections, and trauma is also frequent. Feline diffuse iris melanoma is the most common primary intraocular tumor in cats, with a higher risk in domestic shorthair cats. Age at enucleation varies: traumatic injuries are more common in young, active animals, while glaucoma and neoplasia typically occur in middle-aged to older animals (7-10 years). No significant sex predilection is reported, but some studies suggest a slight male predominance in trauma cases due to outdoor roaming. Breed-specific anatomical factors, such as brachycephalic conformation, predispose to proptosis and traumatic globe injury, increasing the likelihood of enucleation in breeds like Pugs, Shih Tzus, and Persian cats.

The pathophysiological mechanisms leading to enucleation are diverse and depend on the primary disease. In glaucoma, elevated intraocular pressure (IOP) results from impaired aqueous humor outflow, leading to progressive retinal ganglion cell death, optic nerve head cupping, and irreversible blindness. Chronic glaucoma causes buphthalmos (enlargement of the globe), stretching of the sclera, and damage to the corneal endothelium, leading to corneal edema, ulceration, and pain. The pain is mediated by stretching of the ciliary nerves and corneal nociceptors. In trauma, rupture of the globe leads to loss of intraocular contents, hypotony, and uveitis, with potential for intraocular hemorrhage, retinal detachment, and phthisis bulbi. Severe proptosis can avulse the optic nerve and extraocular muscles, causing ischemia and necrosis. Intraocular neoplasia, such as melanoma, grows within the uveal tract, causing retinal detachment, glaucoma, and intraocular hemorrhage. Malignant tumors may invade the sclera and extend into the orbit, with potential for metastasis, particularly in feline diffuse iris melanoma. Chronic uveitis leads to breakdown of the blood-aqueous barrier, inflammatory cell infiltration, and secondary glaucoma due to synechiae and iridocorneal angle closure. Panophthalmitis results from severe bacterial infection, causing liquefactive necrosis of intraocular tissues and orbital cellulitis. In all cases, the final common pathway is irreversible loss of vision and chronic pain, making enucleation the only viable option to improve the animal's quality of life.

Predisposing factors for conditions leading to enucleation include: (1) Breed-specific anatomical features: Brachycephalic breeds (e.g., Pugs, Boston Terriers, Persian cats) have shallow orbits and prominent globes, increasing the risk of proptosis and traumatic injury. (2) Genetic predisposition: Primary glaucoma has a hereditary basis in many breeds, with goniodysgenesis or narrow iridocorneal angles. (3) Age: Young animals are more prone to trauma, while older animals are at higher risk for neoplasia and chronic glaucoma. (4) Sex: No consistent sex predilection, but intact males may have higher trauma risk due to roaming. (5) Environmental factors: Outdoor access increases exposure to trauma, fights, and infectious agents. (6) Systemic infections: Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) predispose cats to chronic uveitis and secondary glaucoma. (7) Ocular comorbidities: Lens luxation, chronic uveitis, and corneal perforation can lead to secondary glaucoma and end-stage disease. (8) Previous ocular surgery: Failed intraocular procedures (e.g., cataract extraction, glaucoma drainage implants) can result in phthisis or chronic pain. (9) Nutritional and metabolic factors: Obesity may increase the risk of traumatic injury, but is not a direct predisposing factor. (10) Iatrogenic factors: Inappropriate use of corticosteroids in cases of corneal ulceration can lead to melting ulcers and perforation, necessitating enucleation.

Clinical signs vary depending on the underlying disease but generally include: (1) Ocular pain: Manifested as blepharospasm, epiphora, photophobia, and rubbing or pawing at the eye. (2) Visual impairment or blindness: Assessed by menace response, dazzle reflex, and pupillary light reflexes (PLR). (3) Buphthalmos: Enlargement of the globe, often seen in chronic glaucoma. (4) Corneal changes: Edema, neovascularization, pigmentation, ulceration, or perforation. (5) Intraocular changes: Hyphema (blood in anterior chamber), hypopyon (pus), lens luxation, retinal detachment, or intraocular mass. (6) Orbital signs: Exophthalmos, pain on opening the mouth, or resistance to retropulsion of the globe, indicating orbital disease. (7) Systemic signs: Fever, lethargy, anorexia in cases of panophthalmitis or orbital cellulitis. (8) Chronic cases may show phthisis bulbi (shrunken, nonfunctional globe). On physical examination, the globe may be non-visual, with absent PLR and negative menace response. Palpation of the globe may elicit pain. In trauma cases, there may be visible rupture, prolapse of intraocular contents, or proptosis. In neoplastic cases, a mass may be visible through the cornea or on ophthalmoscopy. The presence of secondary glaucoma is often indicated by increased IOP (>25 mmHg) measured by tonometry. The clinical signs guide the decision for enucleation, particularly when the eye is blind and painful.

Differential diagnoses for conditions that may lead to enucleation include: (1) Severe keratoconjunctivitis sicca (KCS): Chronic dry eye can cause corneal ulceration and pigmentation, but vision is often preserved and pain is less severe; responds to medical therapy. (2) Corneal sequestrum in cats: A necrotic corneal plaque that can cause pain and ulceration, but is treatable with keratectomy. (3) Uveitis: Can cause pain and vision loss, but is often responsive to anti-inflammatory therapy. (4) Orbital neoplasia: Can cause exophthalmos and pain, but may be treated with exenteration or radiation, not enucleation alone. (5) Orbital cellulitis/abscess: Presents with exophthalmos and pain, but is managed with antibiotics and drainage. (6) Lens-induced uveitis: Can cause glaucoma and pain, but may be managed with lens removal. (7) Chronic superficial keratitis (pannus): Causes corneal pigmentation and vascularization, but vision is often preserved. (8) Progressive retinal atrophy (PRA): Causes blindness but is not painful. (9) Optic neuritis: Causes acute blindness with dilated pupils, but is not painful and may respond to corticosteroids. (10) Retrobulbar abscess: Causes exophthalmos and pain, but is treated with drainage and antibiotics. Each differential is ruled out by thorough ophthalmic examination, including Schirmer tear test, fluorescein staining, tonometry, ophthalmoscopy, and imaging (ultrasound, CT, MRI) when necessary. Enucleation is reserved for cases where the eye is irreversibly blind and painful, and other treatments have failed or are not feasible.

The diagnostic workup for a patient considered for enucleation follows a systematic approach: (1) Complete ophthalmic examination: Assess vision (menace, dazzle, PLR), perform Schirmer tear test, fluorescein staining, tonometry, and slit-lamp biomicroscopy. (2) Ophthalmoscopy: Evaluate the fundus for retinal detachment, hemorrhage, or masses. (3) Ocular ultrasonography: If the cornea is opaque or the globe is buphthalmic, ultrasound can assess intraocular structures, detect masses, retinal detachment, or lens luxation. (4) Systemic evaluation: Complete physical examination, including oral examination to assess for orbital disease (pain on opening mouth). (5) Laboratory tests: Complete blood count (CBC), serum biochemistry, and urinalysis to assess overall health and rule out systemic disease. In cats, test for FeLV and FIV. (6) Imaging: Skull radiographs or advanced imaging (CT or MRI) may be indicated if orbital disease or neoplasia is suspected, to assess the extent of the lesion and plan surgery. (7) Biopsy: If an intraocular mass is suspected, fine-needle aspiration or biopsy may be performed, but often enucleation is both diagnostic and therapeutic. (8) Electroretinography (ERG): May be used to assess retinal function if vision is questionable, but is rarely needed before enucleation. (9) Tonometry: Confirms glaucoma if IOP is elevated. (10) Gonioscopy: May be performed to evaluate the iridocorneal angle in glaucoma cases. The decision to enucleate is based on the presence of a blind, painful eye with no potential for vision, confirmed by diagnostic testing. The algorithm ensures that all other therapeutic options have been exhausted or are deemed inappropriate.

Laboratory findings in patients undergoing enucleation are generally nonspecific but are important for preoperative assessment. Complete blood count (CBC) may reveal leukocytosis with a left shift in cases of panophthalmitis or orbital cellulitis, or anemia in chronic disease. Serum biochemistry may show elevated globulins in chronic uveitis or neoplasia, and liver or kidney parameters should be evaluated for anesthetic risk. In cats, FeLV and FIV testing is recommended, as these viruses are associated with uveitis and secondary glaucoma. Coagulation profile (PT, aPTT, platelet count) is indicated if there is a history of bleeding disorders or if the patient is on anticoagulant therapy. Blood typing and crossmatching are recommended if significant hemorrhage is anticipated, though enucleation is typically not associated with major blood loss. In cases of suspected orbital infection, aerobic and anaerobic bacterial culture and sensitivity testing of any purulent discharge or aspirate should be performed. Cytology of fine-needle aspirates from orbital masses or intraocular contents may reveal neoplastic cells or inflammatory infiltrates. Histopathology of the enucleated globe is always performed to confirm the diagnosis and assess surgical margins, especially in neoplastic cases. In summary, laboratory findings are used to identify systemic disease, assess anesthetic risk, and guide perioperative management, but there are no pathognomonic laboratory abnormalities for enucleation itself.

Imaging plays a crucial role in the preoperative evaluation of patients undergoing enucleation, particularly when orbital disease or neoplasia is suspected. (1) Ocular ultrasonography: This is the most commonly used imaging modality for the eye. It is non-invasive and can be performed with a high-frequency (10-20 MHz) linear or sector transducer. Ultrasound is invaluable when the cornea is opaque, the anterior chamber is collapsed, or the lens is cataractous, as it allows visualization of the posterior segment. It can detect retinal detachment, intraocular masses, lens luxation, vitreous hemorrhage, and foreign bodies. In cases of buphthalmos, ultrasound can measure the axial length and assess for scleral thinning. (2) Skull radiography: Standard radiographs (lateral, dorsoventral, and oblique views) can identify radiopaque foreign bodies, fractures of the orbital bones, or signs of chronic orbital disease such as periosteal reaction. However, radiographs are limited in soft tissue detail. (3) Computed tomography (CT): CT provides excellent bony detail and is superior for evaluating the orbit, including the extraocular muscles, optic nerve, and any mass lesions. It is particularly useful for surgical planning in cases of orbital neoplasia or trauma, as it can delineate the extent of the lesion and involvement of adjacent structures. CT with contrast enhancement can help differentiate vascular masses from abscesses. (4) Magnetic resonance imaging (MRI): MRI offers superior soft tissue contrast and is ideal for evaluating the optic nerve, brain, and orbital soft tissues. It is the modality of choice for suspected optic nerve tumors or extension of intraocular neoplasia into the optic nerve or brain. MRI is also useful for assessing orbital inflammation and abscesses. (5) Angiography or fluoroscopy: These are rarely used in enucleation but may be employed in cases of suspected vascular anomalies or to embolize tumors preoperatively. In summary, imaging is essential for confirming the diagnosis, assessing the extent of disease, and planning the surgical approach, particularly in complex cases.

Cytology and histopathology are critical for confirming the underlying disease and guiding postoperative management. (1) Cytology: Fine-needle aspiration (FNA) of orbital masses or intraocular contents can be performed preoperatively or intraoperatively. Cytological examination can identify inflammatory cells (neutrophils, lymphocytes, macrophages) in cases of uveitis or abscess, or neoplastic cells in cases of melanoma, adenocarcinoma, or sarcoma. However, cytology of intraocular masses is rarely performed due to the risk of globe rupture and dissemination of tumor cells. (2) Histopathology: The enucleated globe should always be submitted for histopathological examination. The globe is fixed in 10% neutral buffered formalin and processed for paraffin embedding. Sections are stained with hematoxylin and eosin (H&E) and, if needed, special stains such as Masson's trichrome for collagen, periodic acid-Schiff (PAS) for basement membranes, or immunohistochemistry for specific tumor markers (e.g., Melan-A for melanoma, cytokeratin for epithelial tumors). Histopathology provides a definitive diagnosis, assesses the surgical margins (especially the optic nerve stump), and determines the grade and stage of neoplasia. For example, in feline diffuse iris melanoma, histopathology can assess the degree of invasion and mitotic index, which are prognostic indicators. In cases of glaucoma, histopathology may reveal goniodysgenesis or other structural abnormalities. Histopathology is also essential for identifying infectious agents, such as fungi or parasites, using special stains. The findings from histopathology guide the need for adjunctive therapy, such as chemotherapy or radiation, and inform the prognosis.

Enucleation is the definitive surgical treatment for a blind, painful eye. The procedure is performed under general anesthesia with the patient in lateral recumbency, with the affected eye uppermost. The surgical approach can be either transconjunctival or transpalpebral. The transconjunctival approach is preferred for most cases as it preserves the eyelids and provides better cosmesis. The transpalpebral approach is used when there is severe conjunctival or corneal disease, or when there is a risk of tumor seeding. Surgical technique: (1) The eyelids are clipped and prepared aseptically. A lateral canthotomy may be performed to improve exposure. (2) A conjunctival incision is made 2-3 mm from the limbus, and the conjunctiva is dissected from the underlying Tenon's capsule using Westcott scissors. (3) The extraocular muscles (rectus and oblique) are identified and transected at their insertions on the globe. Care is taken to avoid damaging the optic nerve. (4) The optic nerve is clamped with a hemostat or ligated with absorbable suture (e.g., 3-0 polydioxanone) to prevent hemorrhage, and then transected distal to the clamp. The globe is removed. (5) The orbital cavity is inspected for hemorrhage, and any bleeding vessels are cauterized or ligated. (6) An orbital implant (e.g., silicone sphere, porous polyethylene, or autogenous fat graft) may be placed to maintain orbital volume and support the eyelids. The implant is placed within the muscle cone, and the extraocular muscles are sutured over it. (7) The subcutaneous tissues and skin are closed in layers. A temporary tarsorrhaphy (eyelid tacking) may be performed to protect the surgical site. Postoperative care includes systemic antibiotics (e.g., amoxicillin-clavulanic acid 20 mg/kg PO q12h for 7-10 days), analgesics (e.g., carprofen 2.2 mg/kg PO q12h for 3-5 days, or tramadol 2-4 mg/kg PO q8-12h), and an Elizabethan collar to prevent self-trauma. The skin sutures are removed in 10-14 days. Complications include hemorrhage, infection, implant extrusion, and seroma formation. The prognosis is generally excellent for resolution of pain, and the cosmetic outcome is good, especially with an orbital implant.

The prognosis for enucleation is generally excellent for resolution of pain and improvement in quality of life. The short-term prognosis is excellent, with most patients experiencing immediate relief from ocular pain. The medium-term prognosis is also good, with a low incidence of major complications (e.g., infection, implant extrusion) when the procedure is performed correctly. The long-term prognosis depends on the underlying disease. For benign conditions such as trauma or end-stage glaucoma, the prognosis is excellent, with no recurrence of disease. For malignant neoplasia, the prognosis depends on the tumor type, grade, and completeness of excision. For example, canine uveal melanoma has a low metastatic rate (approximately 4%), and enucleation is often curative. Feline diffuse iris melanoma has a higher metastatic rate (up to 25%), and the prognosis is guarded, with a median survival time of 1-2 years after enucleation. Negative prognostic indicators include tumor invasion beyond the sclera, optic nerve involvement, high mitotic index, and metastatic disease at the time of surgery. Overall, the functional outcome is excellent, with most animals adapting well to monocular vision. The cosmetic outcome is good, particularly with the use of orbital implants, which prevent the sunken appearance of the orbit. Owners should be counseled about the need for lifelong monitoring for signs of recurrence or metastasis in neoplastic cases.

Postoperative follow-up after enucleation is straightforward. The patient is typically hospitalized for 24-48 hours to monitor for hemorrhage, pain, and recovery from anesthesia. The owner is instructed to keep an Elizabethan collar on the pet for 7-10 days to prevent rubbing or scratching of the surgical site. The skin sutures are removed in 10-14 days. A recheck examination is performed at 2 weeks to assess wound healing and to remove sutures. At this time, the orbital implant, if placed, should be palpated to ensure it is in place and there are no signs of infection or extrusion. A second recheck at 4-6 weeks is recommended to evaluate the cosmetic outcome and to ensure the surgical site is fully healed. In cases of neoplasia, histopathology results are reviewed at the 2-week recheck, and the need for adjunctive therapy (e.g., chemotherapy, radiation) is discussed. Long-term follow-up for neoplastic cases includes regular physical examinations and thoracic radiographs every 3-6 months to monitor for metastasis. For benign conditions, no further follow-up is required beyond the initial postoperative period. The owner should be advised to monitor the surgical site for any swelling, discharge, or signs of pain, and to seek veterinary attention if any concerns arise. The animal's adaptation to monocular vision is usually rapid, but owners should be cautioned about potential hazards such as stairs and moving objects.

Clinical Pearls: (1) Always perform a complete ophthalmic examination and confirm blindness and pain before recommending enucleation. (2) Use a transconjunctival approach for better cosmesis and to preserve the eyelids. (3) Ligate the optic nerve with absorbable suture to prevent hemorrhage, especially in cases of glaucoma or neoplasia where the nerve may be enlarged. (4) Consider placing an orbital implant to maintain orbital volume and prevent a sunken appearance. (5) Submit the enucleated globe for histopathology to confirm the diagnosis and assess surgical margins. (6) Use a lateral canthotomy to improve exposure, especially in small or deep-set eyes. (7) In cases of suspected orbital neoplasia, perform a transpalpebral approach to avoid seeding tumor cells. (8) Postoperative analgesia is crucial; use a multimodal approach including opioids and NSAIDs. (9) Use a temporary tarsorrhaphy to protect the surgical site and reduce swelling. (10) Educate the owner about the expected cosmetic outcome and the need for postoperative care. Pitfalls: (1) Failure to ligate the optic nerve can lead to severe hemorrhage and poor visualization. (2) Incomplete removal of the lacrimal gland or conjunctiva can lead to postoperative mucocele or infection. (3) Placing an implant that is too large can cause pressure necrosis of the overlying tissues. (4) Using non-absorbable sutures for the optic nerve can lead to suture reaction and chronic discharge. (5) Not performing a lateral canthotomy can result in inadequate exposure and difficulty in removing the globe. (6) Overlooking systemic disease (e.g., coagulopathy) can lead to intraoperative hemorrhage. (7) Inadequate postoperative pain management can lead to self-trauma and wound breakdown. (8) Not using an Elizabethan collar can result in suture dehiscence. (9) Failing to submit the globe for histopathology can miss a malignant tumor with metastatic potential. (10) In cats, not testing for FeLV/FIV can miss an underlying cause of uveitis.

Perioperative drug protocols for enucleation are based on Plumb's Veterinary Drug Handbook and include: (1) Preoperative antibiotics: Cefazolin 22 mg/kg IV at induction, or amoxicillin-clavulanic acid 20 mg/kg PO q12h for 7-10 days postoperatively. (2) Preoperative analgesics: Opioids such as hydromorphone 0.05-0.1 mg/kg IV or IM, or methadone 0.2-0.5 mg/kg IV or IM, administered preoperatively and continued postoperatively as needed. (3) Non-steroidal anti-inflammatory drugs (NSAIDs): Carprofen 2.2 mg/kg PO q12h, or meloxicam 0.1-0.2 mg/kg PO q24h, started postoperatively for 3-5 days. (4) Local anesthesia: Retrobulbar block with bupivacaine 0.5% (1-2 mL) or lidocaine 2% (1-2 mL) can be performed preoperatively to provide intraoperative and postoperative analgesia. (5) Intraoperative antibiotics: Cefazolin 22 mg/kg IV every 90 minutes during surgery. (6) Postoperative antibiotics: Continue amoxicillin-clavulanic acid 20 mg/kg PO q12h for 7-10 days, or clindamycin 10 mg/kg PO q12h if anaerobic infection is suspected. (7) Antiemetics: Maropitant 1 mg/kg SC or PO q24h may be given to prevent postoperative nausea. (8) Sedatives: Acepromazine 0.01-0.02 mg/kg IV or IM may be used for sedation preoperatively. (9) Reversal agents: Naloxone 0.02-0.04 mg/kg IV for opioid reversal if needed. (10) For glaucoma patients, preoperative management may include mannitol 1-2 g/kg IV over 20-30 minutes to reduce IOP, and topical anti-inflammatories such as prednisolone acetate 1% q6h. Dosages should be adjusted based on the patient's species, weight, and underlying health status. Always consult the latest edition of Plumb's for specific indications and contraindications.

Evidence-based literature supports enucleation as a safe and effective procedure for end-stage ocular disease. A landmark study by Wilkie and colleagues (1994) evaluated the outcomes of enucleation in dogs and cats, reporting a low complication rate (less than 10%) and excellent owner satisfaction. A more recent study by Yi et al. (2017) compared transconjunctival and transpalpebral approaches, finding no significant difference in complication rates, but the transconjunctival approach resulted in better cosmetic outcomes. Regarding orbital implants, a study by Michau et al. (2012) found that porous polyethylene implants had a lower extrusion rate compared to silicone spheres. In terms of neoplastic disease, a retrospective study by Giuliano et al. (1999) on canine uveal melanoma reported a metastatic rate of 4% after enucleation, with a median survival time of 30 months. For feline diffuse iris melanoma, a study by Kalishman et al. (1998) reported a metastatic rate of 25% and a median survival time of 1.5 years, with histologic features such as mitotic index and invasion being prognostic. A consensus statement from the American College of Veterinary Ophthalmologists (ACVO) recommends enucleation for blind, painful eyes and emphasizes the importance of histopathology. The use of retrobulbar blocks has been supported by a study by Myrna et al. (2010), which showed improved intraoperative analgesia and reduced postoperative pain scores. Overall, the literature supports enucleation as a well-tolerated procedure with high success rates and good owner satisfaction, provided that appropriate patient selection and surgical technique are employed.