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Louise A Mawn

Publications and source records attributed to Louise A Mawn.

9 recordsLinked to original sources
PubMed2004

Development of an orbital endoscope for use with the free electron laser.

PURPOSE: To explore the feasibility of designing, constructing, and testing an orbital endoscope for use with the free electron laser (FEL). METHODS: An experimental study with an author-designed laser delivery system through an endoscope was conducted. Two adult pig cadavers and 6 fresh human cadavers had orbital endoscopy performed to develop a method of optic nerve sheath fenestration (ONSF) with the FEL. Twelve orbits were used to develop the surgical procedure by comparing visualization media and surgical technique. In the first 7 trials, a different variable was changed; the procedure was then refined in the human cadaver experiments. An ONSF was performed with the FEL (6.45 microm, 30 Hz, 2 to 3 mJ, 250-microm spot size) through a glass hollow wave guide introduced through an endoscope in 4 human cadaver orbits. RESULTS: Visualization of the orbital structures was clearest with carbon dioxide; sodium hyaluronate did not displace the fat, and saline hydrated the orbital fat. Biopsy forceps alone did not produce a dural window in the four trials that used the forceps. A dural window was made by using the FEL through a glass hollow wave guide adapted to the Olympus HYF-XP endoscope in the second, third, fifth, and sixth human trials with the FEL. Histologic evidence of the ONSF was produced. CONCLUSIONS: A hollow wave guide capable of transmitting the FEL through an endoscope was successfully constructed. ONSF with the FEL applied through an endoscope is technically feasible. Additional studies are currently examining techniques to improve intraorbital endoscopy.

Animals↗
PubMed2004

Erdheim-chester disease mimicking multiple meningiomas syndrome.

We describe a rare case of non-Langerhans histiocytosis, consistent with Erdheim-Chester disease (ECD), which presented with lesions resembling multiple meningiomas. The patient was initially evaluated for migraine headaches. Initial MR imaging demonstrated a parasellar mass and a second mass near the torcula considered to represent meningiomas. Within 1 year, he developed bilateral orbital lesions surrounding both optic nerves, which were also considered meningiomas. Biopsy of one orbital mass revealed a non-Langerhans histiocytosis. Subsequently, soft tissue masses, a pericardial effusion, and bone lesions consistent with ECD were identified.

Adult↗
PubMed2003

Chronic and acute analysis of optic nerve sheath fenestration with the free electron laser in monkeys.

BACKGROUND AND OBJECTIVES: The Amide II wavelength (6.45 microm) produced by the free electron laser (FEL) can efficiently create an optic nerve sheath fenestration in rabbits. We wished to determine if it would be equally successful in macaque monkeys and to determine the histopathologic changes between traditional scissors or knife optic nerve sheath fenestration to FEL fenestration. STUDY DESIGN/MATERIALS AND METHODS: Optic nerve sheath fenestration was performed using either the FEL (6.45 microm, 30 Hz, 2-3 mJ, 325-microm spot size) through a hollow waveguide probe in 12 eyes or with a scissors or a knife in 6 eyes. The monkeys survived 1 month with the fellow optic nerve operated acutely just prior to sacrifice. Optic nerves were evaluated histologically. RESULTS: Less tissue manipulation was required using the FEL surgical probe. Electroretinograms showed minimal or no change. Tissue responses using either method were similar following chronic or acute incisions. Mild upregulation of vimentin and glial fibrillary acid protein (GFAP) was seen in astrocytes adjacent to the fenestration, but no change in S100 beta was evident. CONCLUSIONS: The FEL energy at 6.45 microm delivered through a hollow waveguide appears capable of efficiently and safely producing an optic nerve sheath fenestration in monkeys. This innovative surgical technique should be considered for human use.

Animals↗
PubMed2003

Dysmorphophobia.

Explore the source record for details and available documents.

Adult↗
PubMed2003

Metastatic gastroesophageal junction adenocarcinoma to the extraocular muscles.

OBJECTIVE: To present one definitive and one probable case of gastroesophageal adenocarcinoma metastases to the extraocular muscles. DESIGN: Two observational case reports. METHODS: Two interventional case reports with clinical pathologic correlation and review of the literature. Vanderbilt University Institutional Review Board approval was obtained for this report. MAIN OUTCOME MEASURES: We analyzed the presenting symptoms, visual acuity, motility, and external examination. RESULTS: Computed tomography showed nodular enlargement of an isolated rectus muscle. Histopathologic examination confirmed the diagnosis of metastatic gastrointestinal carcinoma in one case. The orbital neoplasm contained signet ring cells, classically seen in gastrointestinal malignancy. CONCLUSIONS: Metastasis from gastrointestinal carcinoma should be considered in the differential diagnosis of a patient presenting with diplopia or visual loss, particularly with a recent history of gastrointestinal malignancy.

Adenocarcinoma↗
PubMed2003

Blindness associated with enlarging mycotic aneurysm after cavernous sinus thrombosis.

PURPOSE: We report a patient with an enlarging internal carotid mycotic aneurysm secondary to septic cavernous sinus thrombosis presenting with acute visual loss. DESIGN: Single observational case report. METHODS: Retrospective review of the medical record and review of the literature. RESULTS: A 19-year-old man with residual left sixth nerve palsy and decreased vision in his left eye caused by left cavernous sinus thrombosis secondary to pansinusitis was seen 2 weeks after discharge with acute decreased visual acuity in the right eye. A workup revealed an enlarging left carotid/ophthalmic aneurysm that compressed the optic chiasm and right optic nerve. The patient was taken to the interventional angiography suite, where his left internal carotid artery was occluded endovascularly. The patient's vision improved on discharge. CONCLUSIONS: Visual loss caused by a mycotic carotid aneurysm is an infrequent sequelae after cavernous sinus thrombosis and is not well described in the literature. To our knowledge, this is the first reported case of acute visual loss associated with a mycotic ophthalmic aneurysm. The result of treatment was good in this case, with the patient's visual acuity returning to pretreatment status.

Adult↗
PubMed2003

The bioceramic orbital implant: experience with 107 implants.

PURPOSE: To assess the problems associated with the Bioceramic (Aluminum oxide, Al(2)O(3)) orbital implant. METHODS: A consecutive case series of 107 patients receiving a Bioceramic orbital implant by two surgeons over a 3-year period were reviewed. The authors analyzed patient age, type of surgery, size of implant, peg system, follow-up duration, time of pegging, complications encountered, and treatment. RESULTS: Seven patients were lost to follow-up after 2 months, leaving 100 patients who were followed from 3 to 38 months (average, 13.4 months). Three patients died during the follow-up period (one with 2 months' follow-up, one with 7 months' follow-up, and the third with 9 months' follow-up). Implant-related problems occurred in 11 (11%) patients. Discharge occurred in 5 (5%) patients, implant exposure in 2 (2%), socket discomfort in 1 (1%), trochleitis in 1 (1%), and conjunctival thinning in 2 (2%). Peg problems occurred in 11 (34.3%) of 32 pegged patients: discharge in 4 (12.5%) and in 1 patient (3.1%) each, pyogenic granuloma, conjunctiva overgrowing the peg, implant exposure around the sleeve, clicking, accumulation of black material, and broken peg during insertion. Infection did not occur in any patient. CONCLUSIONS: The Bioceramic orbital implant represents an alternative porous orbital implant that is biocompatible with orbital tissues, easy to manufacture, structurally strong, and less expensive than other commercially available porous orbital implants (e.g., Bio-Eye hydroxyapatite implant). Problems encountered with its use are similar to those seen with the Bio-Eye orbital implants but appear to occur less often. The incidence of exposure associated with the Bioceramic implant is less than that reported for the Bio-Eye.

Adolescent↗
PubMed2003

July 2002: 66-year-old female with a one-year history of progressive left proptosis.

The July 2002 Case of the Month (COM). This 66-year-old Caucasian female presented with gradually increasing protrusion of her left eye over a one-year period. She complained of increased tearing and foreign body sensation. The physical examination revealed a visual acuity of 20/20, normal color testing, full vision field with motility of her left eye limited in lateral gaze. Pupils were round, symmetric, with no afferent pupillary defect noted. On external examination, her left eye was grossly proptotic with resistance to retropulsion. She had 4 mm proptosis of the left eye. Computed tomography and MR imaging demonstrated a left retro-orbital mass with gadolinium enhancement and focal remodeling of orbital bones. She underwent surgical resection of tumor with a diagnosis of solitary fibrous tumor, and postoperatively she was symptom free. The histopathological differential diagnoses of spindle cell neoplasms of the orbit are discussed. Five months after surgery, no evidence of tumor recurrence was seen on neuroimaging and her vision was 20/20.

Aged↗