Russell W. Neuhaus

The porous polyethylene (Medpor) spherical orbital implant: a retrospective study of 136 cases.

Purpose To evaluate complications and risk factors associated with the placement of wrapped and unwrapped porous polyethylene (PP) spherical implants after evisceration, enucleation, or secondary implantation. Methods A retrospective, interventional, noncomparative case series of consecutive cases of PP implant placement after anophthalmic socket surgery performed by three surgeons over a 5-year period. A PP spherical implant was placed in 133 patients, 61 women (2 bilaterally) and 72 men (1 bilaterally). There were 91 enucleations, 30 eviscerations, and 15 secondary implant placements. Sixty-six (48.5%) implants were wrapped prior to placement. Parameters evaluated included: age, sex, prior ocular surgery or radiation treatment, indications for surgery, procedure performed, size of PP sphere, material used to wrap the implant, and complications. Results A total of 17 of 136 (12.5%) cases had documented postoperative complications, with implant exposure being the most common. In 5 patients (3.7%), implant exposure developed: 1 after evisceration and 4 after primary enucleation. Three of the five exposures were small and resolved with either observation alone or in one case with surgical revision of the socket. In two cases, the exposures were large enough that removal of the implant was indicated, one after evisceration and the other after enucleation with placement of a wrapped PP sphere. Conclusions Our series revealed no significant difference in exposure rate between wrapped and unwrapped PP sphere implants, nor was the exposure rate affected by whether an eye was eviscerated or enucleated.

Orbital Complications Secondary to Endoscopic Sinus Surgery

Eight cases of significant orbital complications associated with endoscopic sinus surgery are described. The anatomic problems generally fall into four categories: nasolacrimal sac or duct injury, extraocular muscle injury, intraorbital hemorrhage/emphysema, or optic nerve injury. The successful management of each complication depends on a thorough knowledge of the anatomy and pathophysiology of the orbital injury. Return to normal function of the traumatized orbital structures after medical and/or surgical intervention is anticipated. However, direct optic nerve injury with immediate visual field and/or acuity deficit is usually irreversible.

Obtaining Auricular Cartilage for Reconstructive Surgery

The cartilage in the scaphoid fossa between the helix laterally and the antihelix medially provides excellent underlying support for soft-tissue eyelid and nasal reconstruction. After subcutaneous infiltration anesthesia is administered through both the anterior and posterior auricular skin, an incision is made along the posterior rim of the helix. A dissection plane between the perichondrium and skin exposes the cartilage. The cartilage is removed without incising the anterior skin surface. This technique is particularly useful in cicatricial entropion, upper or lower eyelid retraction, eyelid reconstruction, and socket reconstruction.

Complications at Mucous Membrane Donor Sites

Full-thickness mucous membrane is an acceptable autogenous graft to replace the deficient conjunctiva resulting from intrinsic disease, surgical resection for carcinoma, or reconstruction of contracted sockets. The mouth provides an excellent source of mucous membrane graft material with few donor site complications. However, we encountered four cases of donor site complications after full-thickness mucous membrane grafting. All cases involved submucosal scarring with contracture. Because the inner aspect of the mouth is a multicontoured surface, the submucosal scarring resulted in web formation and limitation of movement of the mandible or lip. In two cases, we resected submucosal fibrotic scar tissue and designed a standard or multiple Z-plasty to release mucosal tension. This allowed a return to normal oral function.

Cerebrospinal Fluid Leakage After Dacryocystorhinostomy

The authors have encountered two presumptive cases of cerebrospinal fluid leakage associated with dacryocystorhinostomy. To understand better the pathophysiology, bilateral dacryocystorhinostomies and anatomic dissections were performed on three fresh cadaver specimens. The average distance from the superior bony nasal window to the floor of the anterior cranial fossa was 5.0 mm. The frontal sinus floor overlies the anterior portion of the nasal window, while the thinnest portion of cribriform plate overlies the posterior portion of the nasal window. A bony fracture of the anterior cranial fossa floor and/or cribriform plate resulted from (1) applying a rotational force to the Kerrison ronguer while enlarging the posterior nasal window or (2) fracturing an attenuated superior wall of an ethmoid air cell which has eroded into the orbital roof.

Use of Bioglass for Orbital Volume Augmentation in Enophthalmos: A Rabbit Model (Oryctolagus Cuniculus)

Purpose To investigate the clinical and histologic response of Novabone-C/M as an osteoproductive alloplastic implant for volume augmentation in the orbit in the treatment of enophthalmos and to compare its outcome alone versus its use in combination with autogenous bone or Medpor granules. Methods Novabone-C/M, a bioactive silicone glass material, was implanted in the subperiosteal space of the left orbit of 12 New Zealand White rabbits. The animals were divided into 3 groups, each with 4 animals, based on the material implanted in the orbit: group 1, Novabone alone; group 2, Novabone plus Medpor granules; and group 3, Novabone plus autogenous bone fragments. All rabbits were studied clinically, radiographically, and histologically at 1-, 3-, and 6-month intervals. Animals underwent preoperative and postoperative computed tomography (CT) with 3-dimensional reconstruction, proptosis measurements, and volumetric analysis. Orbit specimens were studied histologically with mineralized bone stain (MIBS) to look for bone formation, reactivity, infection, implant resorption, and migration. Results There were no signs of significant inflammation or infection. Subcutaneous migration of the implant was seen radiographically but not clinically in groups 1 and 3. Induced proptosis averaged 2.5 mm (at 1 month) and showed regression in all groups over a 6-month period but was not statistically significant. Implant volume was markedly reduced in all groups, averaging 69% in group 1, 37% in group 2, and 59% in group 3 at 6 months. New bone formation and bone remodeling was present in all 3 groups at 3 months and only in group 2 at 6 months. The rate and amount of implant remodeling and bone formation was greatest in the Novabone/Medpor group (group 2). Conclusions Bioglass particulate is biocompatible, easy to use in the orbit, and stimulates bone growth. Bioglass is associated with volume loss and migration over 6 months and may not provide adequate volume augmentation in the orbit when used alone for the treatment of enophthalmos. The duration and amount of bone formation may be enhanced when Novabone is used in conjunction with Medpor.

Expression of the epidermal growth factor receptor in conjunctival squamous cell carcinoma

Purpose: To determine whether the tyrosine kinase epidermal growth factor receptor (EGFR) is expressed in squamous cell carcinoma of the conjunctiva. Methods: A retrospective, observational case series of 5 patients with biopsy-proven conjunctival squamous cell carcinoma treated at one institution between January 1996 and April 2004. Medical records and tissue specimens from the 5 patients were reviewed. A control specimen of normal conjunctiva was also obtained from one of the 5 patients. Immunohistochemical analysis was performed using antibodies against EGFR. Results: Immunohistochemical staining showed that EGFR expression was moderate to strong in all tissue specimens, both in the normal mucosa and in the in situ and invasive components of the conjunctival squamous cell carcinomas. Conclusions: An intense expression of EGFR occurs in squamous cell carcinoma of the conjunctiva. Further study is needed to determine whether an EGFR inhibitor that targets this expression would have potential therapeutic benefit in treating squamous cell carcinoma of the conjunctiva.

Silicone Intubation of Traumatic Canalicular Lacerations

To assist in the repair of canalicular injuries, identification of the medial aspect of the canalicular laceration can easily be accomplished by retrograde probing and intubation of the medial canalicular remnant. A dacryocystotomy along the medial side of the nasolacrimal sac will allow direct visualization of the internal nasolacrimal sac anatomy and common internal punctum of the common canalicular system. A retrograde passage of a modified Quickert probe can then be accomplished through the dacryocystotomy incision into the common internal punctum and present in the traumatic wound, identifying the medial aspect of the canalicular laceration.

Penetrating orbital trauma

A small number of patients suffer penetrating injury to the orbit in the absence of trauma to the globe. Hospital records from the Jules Stein Eye Institute and affiliated hospitals were reviewed to obtain such cases. Five cases of penetrating orbital trauma, in which the globe was spared, are discussed. Many of the injuries initially appeared trivial but subsequent complications were severe. A review of these cases suggests that the shape and speed of the penetrating object, the anatomical location of the entry wound, and the physical characteristics of intraorbital structures determine the character and severity of orbital injuries.

The smooth surface tunnel porous polyethylene enucleation implant.

BACKGROUND AND OBJECTIVE To describe early clinical results with the porous polyethylene smooth surface tunnel (SST) enucleation implant. PATIENTS AND METHODS Uncontrolled, prospective interventional case series of patients undergoing enucleation with placement of the SST implant. This implant consists of a porous polyethylene sphere with a smooth anterior surface containing pre-drilled tunnels to facilitate direct suturing of the rectus muscles to the implant without use of an implant wrap. Postoperatively, socket healing was assessed, and prosthesis and socket motility were evaluated by the surgeon using an ordinal scale (0 = no motility to 4 = excellent motility). RESULTS Thirty patients received the SST implant, with a mean follow-up of more than 23 months. Two cases of exposure occurred and were managed surgically without the need for explantation. Mean socket motility was 3.1 on a 0 to 4 ordinal scale, with mean prosthesis motility of 2.8. CONCLUSION The SST implant provides satisfactory socket motility and is generally well tolerated in the anophthalmic socket without the need for wrapping material.