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Biomedical subjects

N Mamalis

Publications and source records attributed to N Mamalis.

At least 73 records · Page 4Linked to original sources
PubMed1991

A comparison of rust-ring removal methods in a rabbit model: small-gauge hypodermic needle versus electric drill.

Corneal rust rings are common findings after removal of a metallic foreign body. These rings should be removed to prevent inflammation and scarring. We compared the corneal damage in rabbit eyes caused by rust-ring removal using two different methods: a small-gauge hypodermic needle and a hand-held electric ophthalmic drill. No significant difference was found in the amount of corneal scarring as graded by a masked observer. However, there was a trend toward deeper stromal damage in the drill-treated subjects (207 +/- 73 microns) than in the needle-treated subjects (172 +/- 61 microns). In light of this finding, we suggest caution in removing central rust rings with an electric drill since an avoidable, permanent scar may result.

Animals↗
PubMed1991

Phacoemulsification combined with pars plana vitrectomy.

Phacoemulsification combined with pars plana vitrectomy was performed on seven patients with both cataracts and vitreoretinal disease. Six of the seven had a posterior chamber intraocular lens (PC-IOL) placed in the capsular bag following cataract extraction. Visual acuities ranging from light perception to hand movement preoperatively, postoperatively ranged from hand movement to 20/25. There were no perioperative complications. During an average follow-up of more than 6 months, neovascular glaucoma developed in one patient, and a conjunctival cyst in another. The PC-IOLs were well tolerated. The small limbal incision used in phacoemulsification allows better control during the vitrectomy procedure and ensures a water-tight wound. In addition, with the limbal approach, the posterior lens capsule is maintained, with all the attendant advantages.

Adult↗
PubMed1990

Air bubble endothelial damage during phacoemulsification in human eye bank eyes: the protective effects of Healon and Viscoat.

Following insertion of either Healon (sodium hyaluronate) or Viscoat (sodium chondroitin sulfate-sodium hyaluronate) into the anterior chamber of human eye bank eyes, a controlled amount of small air bubbles was introduced into the anterior chamber during phacoemulsification. After vital staining, damage to endothelial cells in the central cornea was quantified. Endothelial damage averaged 4.5% in eyes in which no viscoelastic was used (positive control), whereas damage was only 0.4% (P less than .001) in eyes in which a viscoelastic was inserted but no air bubbles were introduced (negative control). Endothelial damage in test specimens using air plus Healon averaged 4.9%. Damage in test specimens using air plus Viscoat averaged 0.3% (P less than .02). As demonstrated by scanning electron microscopy, many areas in the positive controls and in the Healon test specimens were damaged too extensively to quantitate accurately by the method we used. Thus, Viscoat may prevent or lessen damage to the corneal endothelium by small air bubbles during phacoemulsification.

Air↗
PubMed1990

Spectrum of Nd:YAG laser-induced intraocular lens damage in explanted lenses.

A series of explanted intraocular lenses (IOLs) and autopsy globes containing IOLs that had previously had Nd:YAG laser posterior capsulotomy were analyzed at the Intermountain Ocular Research Center. A broad spectrum of laser-induced IOL damage was found. In the majority of instances, the damage was classified as mild and consisted of tiny pits on the IOLs' posterior surface. These pits would not be expected to produce any visually significant consequences. Moderate damage consisted of larger, more extensive pitting, craters, and small cracks. The most severely damaged IOLs showed extensive cracking and focal fracturing of the optic. Extensive damage may result in unacceptable visual blurring, distortion, and glare which in extreme cases may warrant IOL explantation, as presented in a case report.

Aged↗
PubMed1990

Corneal-scleral melt in association with cataract surgery and intraocular lenses: a report of four cases.

Four patients with rheumatoid arthritis had cataract extraction with implantation of an intraocular lens (IOL). Postoperatively three patients developed progressive scleromalacia perforans. All three cases required patch grafting of the sclera and two of them developed progressive melting of the sclera and graft. The fourth case involved progressive corneal melting with extrusion of the IOL despite treatment with penetrating keratoplasties. All four cases developed retinal detachments with loss of vision and three of the eyes were subsequently enucleated. We describe each case and discuss the clinicopathologic correlations of this condition. The need for careful evaluation of rheumatoid arthritis patients with cataract surgery and IOL implantation is emphasized.

Aged↗
PubMed1990

Mucinous adenocarcinoma of the orbit arising from a stable, benign-appearing eyelid nodule.

Mucinous adenocarcinoma is a rare eyelid tumor which should be considered in the differential diagnosis of a nodular or cystic lesion of the eyelid. This lesion may be locally aggressive and requires complete excision to prevent local recurrence or regional metastases. We present what we believe is the first report of a mucinous adenocarcinoma manifesting as a stable, benign-appearing nodule that has already given rise to a much larger secondary lesion. This case underscores the importance of performing a biopsy on even benign-appearing eyelid nodules.

Adenocarcinoma, Mucinous↗
PubMed1990

Blunt ocular trauma secondary to "war games".

"War games" are gaining popularity in the western United States. These recreational contests involve members of one team attempting to shoot their opponents with high-velocity dye or paint pellets fired from air guns. Unfortunately, serious eye injuries occur when participants do not use protective eye wear. We report a case of severe blunt ocular trauma resulting in a hyphema, choroidal rupture, and retinal and vitreal hemorrhage secondary to a paint pellet striking an unprotected eye. This injury resulted in a significant visual defect in this patient.

Adult↗
PubMed1990

Multiple orbital tumors were cavernous hemangiomas.

Two distinct masses in the left orbit were incidentally found in a 48-year-old woman during a computed tomographic scan done to evaluate neurologic complaints. Initial diagnostic considerations focused on a lymphoproliferative disorder or other systemic disease. Orbitotomy revealed two discrete tumors, both cavernous hemangiomas. Although uncommon, cavernous hemangioma should be considered in the differential diagnosis of the patient with multiple orbital lesions.

Female↗
PubMed1990

Amelanotic malignant melanoma of the conjunctiva with local metastasis to the eyelid.

Conjunctival melanomas are uncommon. The amelanotic variety is extremely rare. We describe a patient with an amelanotic melanoma of the superior conjunctiva that was primarily excised, followed by extensive conjunctival resection and liquid nitrogen cryotherapy applied to the tumour bed. Eight months later a local metastatic lesion was noted in the lower eyelid. Eyelid metastasis in conjunctival melanoma is uncommon but may occur owing to the rich lymphatic vasculature within the conjunctiva.

Aged↗
PubMed1989

Acute visual loss due to a calcified optic nerve glioma.

Optic nerve gliomas are slow-growing tumours most commonly seen in children under 10 years of age. Rapidly progressive proptosis and rapid visual deterioration are uncommon but may occur owing to accumulation of mucoid material, necrosis or hemorrhage. We describe a patient with an optic nerve glioma who manifested sudden proptosis and blindness caused by hemorrhage within the optic nerve sheath. The visual acuity returned to 20/25 after surgical decompression of the nerve and high-dose steroid therapy. Histopathological examination was required to establish the diagnosis of optic nerve glioma with extensive calcification. Optic nerve decompression or short-term high-dose steroid therapy, or both, may be helpful in recovering visual function in selected patients with optic nerve gliomas who have acute visual loss.

Adult↗
PubMed1989

Malignant lesions of the eyelid.

Malignant tumors of the eyelid and ocular adnexa are often detected during routine examinations. Basal cell carcinoma is the most common of these tumors, followed by squamous cell carcinoma. Sebaceous gland carcinoma and malignant melanoma are seen less frequently. Malignant eyelid tumors may mimic a number of benign conditions. Early diagnosis requires a high index of suspicion, and biopsy of the lesion is often necessary.

Carcinoma↗
PubMed1989

Merkel cell tumor of the eyelid: a review and report of an unusual case.

We describe a case of a Merkel cell tumor of the eyelid that manifested as a recurrent chalazion. This tumor had the classic characteristics of a Merkel cell neoplasm by light microscopy. Electron microscopy showed dense-core neurosecretory granules and perinuclear microfilaments consistent with the diagnosis. Because a Merkel cell tumor may manifest as a chalazion, pathologic evaluation of all atypical chalazia is essential. Merkel cell tumors are malignant, and they must be treated aggressively to minimize recurrence or metastasis.

Aged↗
PubMed1988

Presumed intraocular nocardiosis in a cardiac-transplant patient.

A 44-year-old cardiac-transplant patient receiving immunosuppressive therapy developed a chorioretinal mass OS. The lesion was consistent with an ocular nocardial infection. The patient also developed a testicular abscess that was shown to contain N. asteroides after orchiectomy. Despite appropriate systemic treatment, the patient developed extensive subretinal scarring OS. This case report is the first to describe an opportunistic ocular infection with N. asteroides after cardiac transplantation.

Adult↗
PubMed1988

Simultaneous bilateral conjunctival and orbital lymphoma presenting as a conjunctival lesion.

A 44-year-old man with the diagnosis of a conjunctival lymphoma in the left eye was also found on further evaluation to have a lymphoma in the opposite orbit. The patient had no systemic signs of the disease, and was treated with localized radiation therapy. Although simultaneous presentation of lymphoma affecting the conjunctiva in one eye and the orbit on the opposite side is rare, any patient with an isolated conjunctival lymphoma should have a careful evaluation of the opposite eye and orbit, including an orbital computed tomographic scan to rule out simultaneous involvement.

Adult↗
PubMed1988

Surgical removal of an "inoperable" neurofibroma.

An 8-month-old girl had ipsilateral ptosis, proptosis, and glaucoma caused by a massive left-sided plexiform neurofibroma. The tumor extended from the cavernous sinus into the orbit, involving the optic nerve, extraocular muscles, and eyelid. Although the prognosis in such cases is considered very poor, most of the mass was excised by a radical neurosurgical and ophthalmologic procedure. Today, the patient remains asymptomatic with no further neurologic defects. This case is unusual in that the glaucoma developed prior to clinically evident eyelid involvement.

Blepharoptosis↗
PubMed1987

Multiple evanescent white-dot syndrome. A report of eight cases.

Multiple evanescent white-dot syndrome (MEWDS) is a newly described clinical disease entity. The authors report on eight patients with findings characteristic of this syndrome. All of the patients were women and relatively young, with an average age of 28.2 years. Patients complained of unilateral black spots in their vision, with an initial visual acuity of 20/25 to 20/60. Examination showed characteristic small, white dots at the level of the retinal pigment epithelium (RPE). Fluorescein angiography demonstrated patchy hyperfluorescent defects at the level of the RPE with some late staining. All patients had good recovery of visual acuity with eventual fading of the white dots.

Adult↗