Biomedical subjects
A Lynch-Nyhan
Publications and source records attributed to A Lynch-Nyhan.
Fibrinolytic therapy for upper-extremity arterial occlusions.
Acute upper-extremity arterial occlusion may be due to embolic phenomena or de novo thrombosis. If the occlusion is left untreated, claudication or ischemia necessitating amputation can occur. Operative Fogarty-balloon embolectomy has been the treatment of choice for this entity. In a 6-year period the authors used fibrinolysis on nine occasions in eight patients to treat acute upper-extremity arterial occlusions. Concomitant balloon angioplasty was helpful in four cases. Success, defined as a normal hand with at least one artery that was continuously patent to the wrist, was achieved in all patients. A single significant groin hematoma was seen. Neither stroke nor death occurred in any case, and no amputations were necessary. Local transcatheter intraarterial administration of urokinase can be considered a first-line treatment for brachial artery embolus and other causes of acute upper-extremity arterial occlusion.
The natural history of pancreatic pseudocysts documented by computed tomography.
The clinical courses of 75 patients with pancreatic pseudocysts documented by computed tomography (CT) were retrospectively reviewed. History, physical examination, laboratory findings and CT scan data were analyzed. The treatment regimen followed during the period spanning the review dictated nonoperative management for those patients with asymptomatic pseudocysts who were able to tolerate oral intake. Operative management was used only for patients with persistent abdominal pain or enlargement or complications of pseudocyst. Approximately one-half of the patients (n = 36, 48 per cent) were managed nonoperatively, and the remainder (n = 39, 52 per cent) were treated operatively. In the group managed nonoperatively, with a mean follow-up period of one year, 60 per cent had complete resolution of the pseudocyst documented roentgenographically, and 40 per cent had pseudocysts that remained stable or decreased in size. Only one pseudocyst-related complication developed in the nonoperative group. No pseudocyst-related mortality occurred in either group. The size of the pseudocyst was a significant predictor of the need for operative drainage. Pseudocysts greater than 6 centimeters in diameter required surgical treatment in 67 per cent, significantly more frequently (p less than 0.05) than the 40 per cent of patients who required operative treatment for pseudocysts less than 6 centimeters in diameter. We conclude that a large proportion of patients with pancreatic pseudocysts, without specific indications for operative treatment, can be safely managed nonoperatively, with careful clinical and roentgenographic follow-up study.
Pulmonary arteriovenous malformations: techniques and long-term outcome of embolotherapy.
Over a 10-year period, 276 pulmonary arteriovenous malformations (PAVMs) were occluded with balloon embolotherapy in 76 patients, 67 (88%) of whom had hereditary hemorrhagic telangiectasia. Eleven patients (14%) were discovered by means of family screening with measurement of arterial blood gases and chest radiography. Epistaxis, dyspnea, hemoptysis, and hemothorax occurred in 79%, 71%, 13%, and 9% of patients, respectively. Clinical histories of strokes and transient ischemic attacks were present in 18% and 37% of patients, respectively. Computed tomographic scans of 59 patients showed stroke in 36%. Sixty-five percent of PAVMs were located in the lower lobes, which correlated with the finding of more pronounced hypoxemia in the upright position. After embolotherapy, symptomatic hypoxemia was corrected, and serial values have remained constant for 5 years. Complications were minimal, and no patient required surgery. Balloon embolotherapy is effective long-term therapy for PAVMs, and family screening should be pursued because of the possibility of a higher frequency of paradoxical embolization (stroke) than previously recognized.
Diagnosis and management of massive gastrointestinal bleeding owing to duodenal metastasis from renal cell carcinoma.
We report 3 cases in which duodenal metastases from renal cell carcinoma caused massive upper gastrointestinal bleeding. In 2 patients the initial symptom was melena and 1 experienced hematobilia. In 2 patients the diagnosis was not suspected until a hypervascular mass was seen on arteriography and the bleeding was controlled by embolization of the gastroduodenal artery. In the third patient an aorto-enteric fistula was suspected on contrast-enhanced computerized tomography but arteriography showed hypervascular metastases in the duodenum.