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Biomedical subjects

M W Wilson

Publications and source records attributed to M W Wilson.

At least 37 records · Page 2Linked to original sources
PubMed1999

Transcatheter embolization for the treatment of misperfusion after hepatic artery chemoinfusion pump implantation.

BACKGROUND: The use of surgically implanted chemoinfusion pumps for the treatment of hepatic metastases from colorectal carcinoma can be complicated by intra- or extrahepatic misperfusion. This may result in suboptimal tumor exposure to the chemotherapeutic agent and injury to other gastrointestinal organs. Misperfusion can be managed by selective arterial transcatheter embolization. METHODS: Between 1989 and 1996, 16 patients with liver metastases from colorectal carcinoma and with hepatic artery chemoinfusion pump misperfusion were treated using transcatheter coil embolization. Six female and 10 male patients (age range, 34-84 years; median, 51.5 years) were identified by retrospective review of the records of the Department of Interventional Radiology. After pump placement, abnormal liver perfusion scan or methylene blue endoscopy study results prompted angiography with coil embolization. After embolization, the imaging studies were repeated and patients were monitored in the Oncology Clinic. RESULTS: Eight patients exhibited intrahepatic misperfusion (group 1) and eight extrahepatic misperfusion (group 2). Coil embolization was immediately successful in 100% of patients in group 1, with restoration of normal hepatic perfusion, and in 75% in group 2. There were no immediate procedure-related complications. Follow-up periods ranged from 1 to 23 months (median, 13.5 months). Embolization was unsuccessful for two patients (in group 2), who tolerated a modified chemotherapeutic regimen, with follow-up periods of 18.5 and 22 months. CONCLUSIONS: Transcatheter coil embolization is the therapy of choice for the management of hepatic artery chemoinfusion pump misperfusion. It is rapid, effective, and well tolerated by patients and obviates the need for additional surgical intervention.

Adult↗
PubMed1999

Severe ocular and orbital toxicity after intracarotid etoposide phosphate and carboplatin therapy.

PURPOSE: To report severe ocular and orbital toxicity after administration of intracarotid etoposide phosphate and carboplatin. METHOD: Case report. RESULTS: A 52-year-old man with glioblastoma multiforme underwent left intracarotid administration of eto poside phosphate and carboplatin inferior to the ophthalmic artery. Within 7 hours, a nonpupillary block angle-closure glaucoma developed secondary to uveal effusion in the ipsilateral eye, which was relieved by cycloplegia. Four days later, severe orbital inflammation resulted in a visual acuity of counting fingers, proptosis, optic neuropathy, and total external ophthalmoplegia in the eye. The patient's condition improved after a lateral cantholysis and administration of high-dose intravenous corticosteroids. Two weeks later, an anterior uveitis occurred in the left eye, which responded to topical corticosteroids. During a 2-month period, the patient recovered to a visual acuity of 20/70, near normal motility, and normal intraocular pressure, and the ocular and orbital inflammation resolved. Preexisting ipsilateral chemotherapy-induced maculopathy became more pronounced. CONCLUSION: Ocular and orbital toxicity after intracarotid etoposide phosphate and carboplatin therapy is infrequently reported.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Comparison of episcleral plaque and proton beam radiation therapy for the treatment of choroidal melanoma.

PURPOSE: To compare the efficacy of iodine-125 (125I) and ruthenium-106 (106Ru) episcleral plaque radiation therapy and proton beam radiation therapy (PBRT) in the treatment of choroidal melanoma. DESIGN: A retrospective, nonrandomized comparative study. METHODS: Charts of patients treated with 125I, 106Ru, and PBRT for choroidal melanoma between January 1988 and June 1996 at St. Bartholomew's Hospital and Moorfields Eye Hospitals were reviewed. MAIN OUTCOME MEASURE: Local control of choroidal melanomas after 125I, 106Ru, or PBRT. RESULTS: A total of 597 patients were identified (125I = 190, 106Ru = 140, PBRT = 267). Patients treated with 106Ru had a significantly greater risk of local tumor recurrence than did patients treated with either 125I (P = 0.0133; confidence interval [CI], 1.26-7.02; risk ratio, 2.97) or PBRT (P = 0.0097; CI, 1.30-6.66; risk ratio, 2.94). A stepwise Cox proportional hazard model found maximal basal diameter to be a significant covariate (P = 0.0033). CONCLUSION: Patients treated with 106Ru had a significantly greater risk of local tumor recurrence than did those patients treated with either 125I or PBRT.

Adolescent↗
PubMed1998

Infection of a porous polyethylene orbital implant with Capnocytophaga.

A 68-year-old woman experienced an infection of a porous polyethylene orbital implant caused by Capnocytophaga after a dental procedure. The infection was unresponsive to both topical and oral antibiotics and required removal of the porous polyethylene orbital implant. Capnocytophaga is a capnophilic, gram-negative bacillus. Capnocytophaga is a normal commensal of the mouth and is responsible for both gingivitis and periodontal disease. Capnocytophaga is a rare cause of ocular infections. This is the first reported patient with an infection of a porous polyethylene orbital implant caused by Capnocytophaga. The authors believe infected integrated orbital implants must be removed because neither topical or systemic therapy provide effective treatment.

Aged↗
PubMed1998

Gadolinium-enhanced magnetic resonance venography of the portal venous system prior to transjugular intrahepatic portosystemic shunts and liver transplantation. Original investigation.

RATIONALE AND OBJECTIVES: The accuracy of gadolinium-enhanced magnetic resonance venography (GdMRV) in identifying visceral venous abnormalities was assessed in patients before they underwent transjugular intrahepatic portosystemic shunt (TIPS) or orthotopic liver transplantation (OLT). METHODS: Twenty-seven patients with portal hypertension underwent GdMRV and transcatheter venography prior to OLT or TIPS. The gadolinium dose was 0.5 mL/kg (0.25 mmol/kg), administered by rapid hand injection. Coronal 3D spoiled gradient-echo GdMRV was performed in a single breath-hold. Four blinded reviewers retrospectively evaluated coronal maximum intensity projection (MIP) images, while two reviewers evaluated the MIPs and multiplanar reconstructions. Abnormalities that could affect transjugular intrahepatic portosystemic shunt or transplantation were noted and compared with the results of corresponding catheter venograms read by a separate blinded reviewer. RESULTS: Abnormalities were identified by GdMRV with a sensitivity and specificity of 83% and 97% for the right hepatic vein, 86% and 100% for the main portal vein (MPV), 42% and 99% for the right portal vein, 54% and 94% for the left portal vein, 61% and 96% for the superior mesenteric vein, and 74% and 91% for the splenic vein. Varices and shunts were correctly identified with a sensitivity of 96%. Multiplanar reconstruction increased MPV sensitivity to 100%. CONCLUSION: Vascular abnormalities that affect TIPS and OLT can be identified by GdMRV. Multiplanar reconstruction increased the accuracy to 100% for the MPV.

Catheterization, Central Venous↗
PubMed1998

Expandable metallic stents in benign tracheobronchial obstruction.

Expandable metallic stents offer advantages over previously available techniques for treating benign tracheobronchial stenosis or obstruction. Endoluminal stent placement offers a rapid and effective means of opening up narrowed airways, and results in excellent relief of symptoms and improvement in pulmonary function. Because they are delivered in a nonexpanded state using flexible over-wire systems, they can be placed using a flexible bronchoscope and can be located in second-order bronchial branches. Metallic stents have been used to treat benign airway obstruction caused by anastomotic narrowing after lung transplantation, infection, congenital lesions, tracheobronchial malacia, inflammatory conditions including relapsing polychondritis, Wegener granulomatosis, and acquired immunodeficiency syndrome, and external compression from benign mediastinal masses or fibrosis. The stents become epithelialized, which prevents migration and permits ciliary activity to continue. Significant complications can occur, including airway inflammation, stent migration, airway erosion, and stent fracture and collapse, but more serious complications are uncommon. Computed tomography is essential in imaging patients being considered for stent placement, as it allows 1) accurate representation of airway anatomy in three dimensions. 2) measurement of airway diameter, 3) evaluation of airway anatomy distal to a narrowed segment and invisible to bronchoscopy, 4) demonstration of dynamic changes in airway morphologic features during forced exhalation in patients with airway malacia, and 5) demonstration of focal or diffuse air trapping in lung peripheral to the abnormal airway. In patients who have had stent placement, computed tomography is valuable in assessing airway morphologic features and dynamics distal to the stent, and can be valuable in assessing stent dysfunction.

Airway Obstruction↗
PubMed1998

Ureteral obstructions and leaks after renal transplantation: outcome of percutaneous antegrade ureteral stent placement in 44 patients.

PURPOSE: To analyze the outcome of percutaneous antegrade ureteral stent placement for treatment of ureteral stenoses and leaks after renal transplantation. MATERIALS AND METHODS: Antegrade pyelography and percutaneous ureteral stent placement were performed in 45 patients with ureteral obstruction (n = 40), leak (n = 3), or both (n = 2). Obstructions were graded as mild, moderate, or complete, and as early (< or = 3 months after transplantation) or late (> 3 months). RESULTS: The outcome of stent placement was successful in 25 (57%) patients (average follow-up, 30 months). The ureteroneocystostomy (UNC) was the most common site of obstructions (22 of 41), leaks (four of five), and successful outcomes (16 of 22). Moderate obstructions were most common (29 of 41) and responded best to treatment (17 of 29). Eighteen (69%) of 26 early obstructions and five (33%) of 15 late obstructions were successfully managed percutaneously. All complications (12 of 45 patients) were minor, with infections the most common (n = 7). No mortality or allograft loss was attributable to stent placement. CONCLUSION: Ureteral stents are safe and effective for the treatment of obstructions and leaks and are particularly effective for early and UNC obstructions. These stents may also be useful for temporary drainage.

Adolescent↗
PubMed1997

Myoepithelioma of the lacrimal gland.

A right orbital tumor was excised from a 76-year-old woman. Pathological examination showed that the tumor was composed of spindle to cuboidal cells arranged in a solid to trabecular pattern. Immunohistochemical stains were positive for S-100 protein, muscle-specific actin, cytokeratins MAK6 and AE1,3, and glial fibrillary acid protein and negative for CD34 in tumor cells. Ultrastructural features of tumor cells included microvillous processes, intercellular junctions, and intracytoplasmic filaments with electron densities. To our knowledge, this is the first non-spindle cell myoepithelioma noted to arise in the lacrimal gland. This tumor likely has a similar biological behavior to pleomorphic adenoma (benign mixed tumor).

Actins↗
PubMed1997

Topical mitomycin C for the treatment of conjunctival and corneal epithelial dysplasia and neoplasia.

PURPOSE: To evaluate the efficacy of topical mitomycin C in treating conjunctival and corneal epithelial dysplasia and neoplasia. METHODS: Seven eyes of seven patients with conjunctival and corneal epithelial dysplasia and neoplasia were treated with one drop of topical mitomycin C 0.04% four times a day for 7 days in alternate weeks. The patients' charts were reviewed retrospectively. Patients with either multiple recurrences or extensive ocular surface involvement were treated. In all eyes, the diagnosis of epithelial dysplasia or neoplasia was confirmed by histopathology before the onset of therapy. Patients were examined at least every 14 days during treatment and examined at intervals after completion of treatment. RESULTS: With topical mitomycin C, six eyes of seven patients had complete clinical regression of their conjunctival and corneal epithelial dysplasia and neoplasia. One eye of one patient had partial clinical regression of conjunctival and corneal epithelial dysplasia. Follow-up after completion of topical mitomycin C therapy and excision of residual disease ranged from 2 to 16 months (mean, 9 months; SD, 4.3 months) and was without clinical sign of recurrence. Topical mitomycin C therapy was associated with transitory ocular discomfort, conjunctival injection, tearing, photophobia, and punctate epithelial keratopathy. CONCLUSION: In this small series of eyes, topical mitomycin C was effective as a treatment for conjunctival and corneal epithelial dysplasia and neoplasia.

Adult↗
PubMed1997

Selective arterial embolization for the control of lower gastrointestinal bleeding.

BACKGROUND: Transcatheter embolization is accepted as a safe method for treating acute bleeding from the upper gastrointestinal (GI) tract. Hesitancy persists using this technique below the ligament of Treitz, based on the belief that the risk of intestinal infarction is unacceptably high, despite mounting clinical evidence to the contrary. METHODS: A series of 17 consecutive patients with angiographically demonstrated small intestinal or colonic bleeding was retrospectively reviewed. The success and complication rate of subselective embolization was assessed. RESULTS: Bleeding was stopped in 13 of 14 patients (93%) in whom embolization was possible, and in 13 of 17 patients (76%) where there was an intention to treat. Sufficiently selective catheterization to permit embolization could not be achieved in 3 patients. No clinically apparent bowel infarctions were caused. CONCLUSION: Subselective embolization is a safe treatment option for lower GI bleeding, suitable for many patients and effective in most. Careful technique and a readiness to abandon embolization when a suitable catheter position cannot be achieved are important.

Adolescent↗
PubMed1996

Heterocyclic ureas: inhibitors of acyl-CoA:cholesterol O-acyltransferase as hypocholesterolemic agents.

A series of diaryl-substituted heterocyclic ureas was prepared, and their ability to inhibit acyl-CoA: cholesterol O-acyltransferase (ACAT) in vitro and to lower plasma total cholesterol in cholesterol-fed animal models in vivo was examined. N-(2,6-Diisopropylphenyl)-N'-tetrazole or isoxazole-substituted heterocyclic ureas proved optimal. A carbon chain of 11-14 carbons substituted 1,3 with respect to the amine provided the optimal side chain. Substitution of the alkyl chain generally lowered activity. Tetrazole urea 2i dosed at 3 mg/kg lowered plasma total cholesterol (TC) 67% in an acute, cholesterol-fed (C-fed) rat model of hypercholesterolemia and 47% in C-fed dogs. Tetrazole 2i, dosed at 10 mg/kg, also lowered TC 52% and raised HDL cholesterol 113% in rats with pre-established hypercholesterolemia.

Animals↗
PubMed1996

Anterior vs posterior intraocular melanoma. Metastatic differences in a murine model.

OBJECTIVE: To study differences in metastatic rate of anterior vs posterior ocular melanoma in a murine model. METHODS: Thirty-eight 12-week-old C57BL6 mice were inoculated into the anterior chamber (AC) or posterior compartment (PC) of the right eye with 5 x 10(5) tissue culture Queens melanoma cells per 5 microL. The right eye was enucleated 14 days after inoculation, and the animal was killed 28 days after inoculation and a necropsy was performed. The eye was evaluated for the presence of melanoma and the mean of the 10 largest nucleoli in tumor cells. Eyes with orbital invasion of the melanoma were excluded. The number of metastases was determined at necropsy. RESULTS: Melanomas grew in 30 of 38 eyes. After exclusion of 9 eyes with orbital invasion of tumor, melanoma was found in 12 mice in the AC group and 9 mice in the PC group. The metastatic rate was significantly lower for AC tumors (33%) than for PC tumors (89%) (P = .02). All AC tumors that metastasized to lungs also metastasized to ipsilateral cervical lymph nodes, and no PC tumors metastasized to ipsilateral cervical lymph nodes. The median number of pulmonary metastases per tumor was significantly smaller for AC tumors than for PC tumors (P = .01) There was a median of 0 metastases (range, 0-14) per AC tumor and 4 metastases (range, 0-38) per PC tumor. CONCLUSION: Posterior ocular melanoma metastasizes more often than anterior ocular melanoma in this murine model.

Animals↗
PubMed1996

Focal posttraumatic choroidal granulomatous inflammation.

PURPOSE: This study was performed to describe the clinicopathologic features of a group of patients with posttraumatic unilateral focal choroidal granulomatous inflammation. METHODS: Enucleated eyes with focal choroidal granulomatous inflammation without clinical signs of contralateral ocular inflammation were identified. Clinical and pathologic features were recorded. RESULTS: Six enucleated eyes that had been injured by projectiles had focal uveal granulomatous inflammation of the posterior choroid. Four eyes had uvea attached to or incarcerated into the wound. Two eyes had foreign material associated with the granulomatous inflammation, and two eyes had a disrupted lens with lens-induced inflammation. Two eyes exhibited the focal granulomatous inflammation at the site of a choroidal rupture. None of the six enucleated eyes contained Dalen-Fuchs' nodules. CONCLUSIONS: Focal choroidal granulomatous inflammation may occur as a result of penetrating ocular trauma. The origin of this condition is unknown, although it likely represents a reaction to a foreign body.

Adolescent↗