Biomedical subjects

J B Selby

Publications and source records attributed to J B Selby.

At least 19 recordsLinked to original sources

PubMed1999

Intravascular sonography in the assessment of traumatic injury of the thoracic aorta.

OBJECTIVE: The objective of this study is to describe the use of intravascular sonography in the evaluation of suspected injury of the thoracic aorta as an adjunctive tool to digital subtraction arteriography (DSA). SUBJECTS AND METHODS: Images of the thoracic aorta were obtained using DSA and intravascular sonography in 20 consecutive patients who underwent arteriography after chest trauma. A 6-French, 12.5-MHz sonography catheter was used for the intravascular sonography study. Diagnoses based on the review of both studies were compared. RESULTS: Five of 20 patients had aortic or great vessel injuries confirmed by surgery. Intravascular sonographic findings were positive (one false-positive) in seven patients, whereas DSA findings were positive in six patients (one false-positive and one false-negative). Surgery showed the lesion that was false-positive using both techniques to be a ductus diverticulum. Intravascular sonographic findings included intimal flaps, intramural lesions (hematomas), pseudoaneurysms, and perivascular hematomas. CONCLUSION: In our initial limited experience, intravascular sonography of the thoracic aorta and great vessels effectively identified traumatic injuries. Intramural injury without pseudoaneurysm formation or obvious intraluminal flap was visualized by intravascular sonography in one patient but was not detected by DSA. On the other hand, a ductus diverticulum was erroneously interpreted as trauma using both techniques. Intravascular sonography is a relatively new procedure with an obvious learning curve in the interpretation of the findings. An atypical ductus diverticulum may still be mistakenly interpreted as a sign of traumatic injury of the aorta. Familiarity with intravascular sonography in the setting of aortic trauma is necessary for correct interpretation of the images. The sonographic findings offer views of the aorta that are complementary to those of aortography.

Adult↗

PubMed1996

Effects of isotonic saline solution resuscitation on blood coagulation in uncontrolled hemorrhage.

BACKGROUND: It has been suggested that fluid resuscitation before surgical control of hemorrhage may lead to increased bleeding because of the elevated blood pressures and clotting factor dilution. This study was designed to assess the effects of isotonic saline solution resuscitation on blood coagulation during uncontrolled hemorrhage. METHODS: Twenty-four female Sprague-Dawley rats were randomized into four groups with different resuscitation regimens: group A, no resuscitation; group B, 40 ml/kg in 4 minutes; group C, 80 ml/kg in 4 minutes; and group D, 80 ml/kg in 1 minute. Baseline blood samples were collected just before a sharp resection of 75% of the tail to initiate the hemorrhage; 15 minutes later the resuscitation began. Additional blood samples were obtained at 60 minutes after resection. The blood was analyzed for platelets, fibrinogen, prothrombin time, and activated partial thromboplastin time. RESULTS: The largest differences between time 0 and 60 minutes were observed in group D with platelets decreasing 43.36% +/- 7.86%, fibrinogen decreasing 57.10% +/- 16.88%, and prothrombin time increasing from an average 16.5 to 19.2 seconds. These differences was statistiacally significant (p <0.05) with the Student's test. CONCLUSIONS: The results suggested that even though the volume of resuscitation fluid did not appear to affect clotting time when compared with that of nonresuscitated animals, the rate of extremely large volume infusions may play an important role in the cessation of bleeding and consequently in the management of uncontrolled hemorrhagic shock.

Animals↗

PubMed1993

The diagnosis of brain death with Tc-99m HMPAO.

Evaluation of blood flow to the brain using various radiopharmaceuticals can be used to confirm brain death. Agents available for this purpose include Tc-99m HMPAO, Tc-99m pertechnetate, Tc-99m glucoheptonate, and Tc-99m DTPA. The authors evaluated the use of Tc-99m HMPAO in 17 patients suspected of brain death using flow images and static images at several time intervals: immediately, between 30 and 60 minutes, and at 2 hours. These studies were compared to several studies performed with Tc-99m glucoheptonate and Tc-99m DTPA. The results of the Tc-99m HMPAO brain death studies correlated well with the patients' clinical conditions. Static images 1 to 2 hours after the injection of 5 to 30 mCi of Tc-99m HMPAO were satisfactory for an accurate interpretation; however, an immediate answer could as easily be supplied using flow images alone. Tc-99m HMPAO was found to be more easily interpreted and less dependent on imaging technique than Tc-99m glucoheptonate and Tc-99m DTPA, and it is the agent of choice for the evaluation of brain death.

Adolescent↗

PubMed1993

Balloon angioplasty above the aortic arch: immediate and long-term results.

OBJECTIVE: Angioplasty above the level of the aortic arch is becoming more common, and the indications for it are increasing. We report our experience with this procedure, including life-table analysis of the long-term results. MATERIALS AND METHODS: We dilated 32 lesions in 29 patients. Early in our series, patients were referred primarily because of arm claudication or vertebrobasilar insufficiency. Subsequently, the indications were expanded to include inflow to left internal mammary-coronary artery bypass grafts, inflow to axillobifemoral bypass grafts, and inflow to dialysis fistulas in the upper extremity. A femoral artery approach was used in 18 patients and an axillary approach was used in 11. Clinical follow-up included evaluation of symptoms and bilateral measurements of peripheral pulses and blood pressure. Follow-up angiograms were obtained in nine patients. RESULTS: Eighteen of the lesions dilated were located in the left subclavian artery, eight were in the right subclavian artery, four were in the axillary or proximal brachial artery, and two were in the innominate artery. Interestingly, three of eight right subclavian arteries treated had an anomalous origin from the arch of the aorta. Initial technical success was 100%. All 29 patients had long-term follow-up of 4-88 months (mean, 36 months). In one patient, stenosis recurred 8 months after angioplasty. This patient subsequently had redilatation. Life-table analysis projected a 7.5-year cumulative primary patency rate of 96.6%. No cerebrovascular complications or embolic events occurred. CONCLUSION: Angioplasty of the great vessels is safe and effective, and the long-term results are favorable when compared with results after surgery. As a result, the indications for this procedure should be broadened.

Adult↗

PubMed1992

A simple method for bile duct anastomosis and interval bile collection in the liver-transplanted rat.

A mini T-tube is introduced for the bile duct anastomosis of rat liver transplantation as well as interval bile collection. The validity of the T-tube was evaluated in 14 liver-transplanted rats and compared to 14 rats using traditional stent for bile duct anastomosis. Changes of biliary tree after the T-tube anastomosis were examined by T-tube cholangiography on sample rats at 4 days and at 4 months after liver grafting. Additionally, bile volumes and rates of bile salt secretion were compared in the continuously flowing cannula and the chronic T-tube fistula in normal rats. The results show that the mini T-tube facilitates bile duct anastomosis and study of bile secretion after liver transplantation in rats without increase in surgical difficulty or interference of biliary enterohepatic circulation.

Anastomosis, Surgical↗

PubMed1992

Thromboembolectomy with the transluminal extraction catheter (TEC) as an adjunct to thrombolysis.

Multiple surgical and percutaneous interventional radiologic techniques have been used to restore blood flow in an acutely ischemic extremity. The transluminal extraction catheter (TEC) system was used as a mechanical thromboembolectomy device to supplement pharmacologic thrombolysis in one patient. In this case, 40 hours of direct intraarterial infusion of urokinase into the occluded vascular segments of a threatened lower extremity resulted in incomplete thrombolysis. Therefore, a 7-F TEC system was advanced percutaneously through the occluded vessels with restoration of luminal patency in all vessels treated. No distal embolization occurred. The TEC system facilitated prompt recanalization of vessels occluded by acute thrombus superimposed on atherosclerotic disease.

Aged↗

PubMed1992

Treatment of hemodialysis fistula pseudoaneurysms with detachable balloons: technique and preliminary results.

Pseudoaneurysm formation is commonly encountered during the life of a dialysis fistula. When these become excessively large or numerous, surgical revision of the graft has been the only treatment option. The authors have treated seven patients by using percutaneous placement of a detachable balloon to occlude a pseudoaneurysm of an upper extremity graft. In four cases the balloon was directed into the pseudoaneurysm from a femoral artery approach. In three cases a direct puncture was made into the pseudoaneurysm for placement of the balloon. The patients were followed up from 1 week to 7 months. Initial technical success was achieved in all seven cases with no complications. Thrombosis of two grafts occurred during the first week after the procedure: one because of herniation of the balloon out of the pseudoaneurysm and one for unknown reasons. One balloon was inadvertently punctured and deflated during subsequent dialysis. Treatment in the other four cases was successful, as evidenced by no further enlargement of the pseudoaneurysms. Direct puncture of the pseudoaneurysm simplifies the procedure and probably decreases the likelihood of balloon herniation because of the orientation of the balloon.

Aneurysm↗

PubMed1992

Normal venous anatomy and collateral pathways in upper extremity venous thrombosis.

Collateral pathways are well known in superior vena cava occlusion but not in axillary or subclavian vein occlusion, even though these occlusions are becoming more common. In a series of 127 arm venograms obtained for suspected venous thrombosis, the authors found 32 instances of subclavian or axillary vein occlusion. The authors reviewed the cases for site of occlusion and definition of collateral pathways. In 15 cases, the occlusion was in the subclavian vein, with collateral flow established chiefly via veins in the neck. Ten cases of axillary vein occlusion with chest wall collateral pathways were identified. Seven cases could not be categorized. Knowledge of these pathways is useful for accurate interpretation of upper extremity venograms. A more thorough understanding of venous pathways in the upper body may aid in the treatment of patients with chronic disease and longterm indwelling central venous catheters.

Arm↗

PubMed1992

Inferior vena cava filters. Indications, safety, effectiveness.

BACKGROUND: Preventing pulmonary embolization by interrupting vena caval flow has been attempted since 1893. Inferior vena cava (IVC) filters have been available for 20 years, and currently there are five filters commercially available in the United States (Greenfield filter, Titanium Greenfield filter, Simon-Nitinol filter, Bird's Nest filter, and LGM or Vena Tech filter) and two other filters under development (Amplatz filter and Günther filter). Although these devices are widely used, their clinical utility and safety have not been completely evaluated. Controlled clinical trials to determine the clinical role for IVC filters have not been attempted, but numerous case series describing the outcomes of the seven current filters have been published. We have systematically reviewed these studies to clarify what is known about the indications, safety, and effectiveness of IVC filters. METHODS: Using the MEDLINE database, all English-language publications since 1970 that included follow-up clinical information after filter insertion were reviewed and eight methodologic guidelines were employed to assess the scientific quality of the clinical information. RESULTS: Twenty-four case series were reviewed: 16 concerned the Greenfield filter (1632 patients), and eight dealt with newer designs (925 patients). Commonly noted methodologic problems included failure to report the initial extent of thromboembolic disease, incomplete description of the patient assembly process, and incomplete and potentially biased outcome assessment. Recurrent clinical pulmonary embolism was rare after filter placement, and only eight deaths from pulmonary embolism were reported. Filter complications were common but rarely life threatening; four (0.16%) deaths from filter complications were noted among the reviewed studies. Thrombotic complications following filter placement included insertion-site deep vein thrombosis and IVC obstruction. These events were rare, but they occurred with all filter types. CONCLUSIONS: Inferior vena cava filters appear to be effective in preventing recurrent pulmonary embolism. Despite the large published experience with IVC filters, many questions remain about their indications, safety, and effectiveness. Anticoagulant therapy, if not contraindicated, should be used in conjunction with filters. While there is no ideal filter, some situations call for specific filters. Filter selection and insertion require experience, modern angiographic technique, and collaboration between clinicians caring for patients and the interventional radiologists or surgeons inserting the device.

Anticoagulants↗

PubMed1992

Interventional radiology of trauma.

Percutaneous transcatheter embolization has become an integral part of the trauma team's armamentarium. Still, it is probably underused in many centers because of lack of familiarity on the part of both the trauma team and the radiologists. Recognition of the role of interventional radiology in vascular trauma can have a significant impact in decreasing the morbidity and mortality associated with this ever-growing problem in our society.

Angiography↗

PubMed1991

Use of methylene blue and selective embolization of the pudendal artery for high flow priapism refractory to medical and surgical treatments.

High flow priapism is often treated effectively with intracavernous vasoconstrictive agents or surgical shunting. If these maneuvers fail treatment is unclear. A 21-year-old black man, who had failed previous pharmacological and surgical therapies, temporarily (8 hours) responded to intracavernous methylene blue, which is known to antagonize endothelial derived relaxation factor. Recurrent priapism was managed successfully by embolization of the left internal pudendal artery with absorbable gelatin sponge. Review of the literature reveals that only 7 patients have been managed with arterial embolization and our case represents the first in which intracavernous methylene blue produced detumescence.

Adult↗

PubMed1991

Results and complications of angioplasty in fibromuscular disease.

Percutaneous transluminal angioplasty (PTA) was used to treat 66 patients with 85 renal artery stenoses due to fibromuscular dysplasia. The hypertension was refractory to medical management in 46 patients, and the initial success rate was 100%. Clinical follow-up has been obtained in all patients, who were followed for as long as 121 months. The recurrence rates were 8% of lesions and 10% of patients. Cumulative patency rate predicted for 10 years was 87.07%. The mean systolic pressure decreased by 52 mm Hg and the mean diastolic pressure decreased by 35 mm Hg in response to treatment. Twenty-six patients (39%) were cured, 39 (59%) were classified as improved, and one (2%) did not respond to PTA. Fourteen of the patients also had elevated blood urea nitrogen and creatinine levels. Renal function was improved in 86% of the patients and stabilized in 14% of the patients. Analysis of the long-term results suggests that PTA should be the initial treatment for choice of patients with fibromuscular dysplasia in the renal arteries.

Angioplasty, Balloon↗

PubMed1991

Results and complications of angioplasty in aortoiliac disease.

Percutaneous transluminal angioplasty was used to treat 340 aortoiliac lesions in 200 patients who were followed for as long as 90 months (mean, 28.7 months; median, 23 months). The initial success rate was 94.7% for lesions and 93.0% for patients. The indications for percutaneous transluminal angioplasty included claudication in 117 patients (58.5%), rest pain or ischemic night pain in 47 (23.5%), limb salvage in 33 (16.5%), and aiding in wound healing in three (1.5%). In the series, 70% of the patients had two or more cardiovascular risk factors. Angioplasty was initially unsuccessful in 14 patients, and 10 patients were lost to follow-up. Follow-up was obtained in 176 patients. The long-term results were analyzed using the life table method to determine cumulative patency. Fourteen patients were considered failures because of recurrent disease or symptoms. The projected 7.5-year cumulative patency rate was 85%. When the response to redilatation was considered, the projected 7.5-year cumulative patency rate was 92%. The results indicate that percutaneous transluminal angioplasty can successfully correct aortoiliac lesions and provide a long-term benefit for as long as 7.5 years.

Angioplasty, Balloon↗

PubMed1990

Inferior vena caval invasion by renal cell carcinoma: false positive diagnosis by venacavography.

We reviewed the records of 22 renal cell carcinoma patients who were referred to this hospital to determine inferior vena caval extension of tumor. Preoperative radiological studies from referring hospitals and this institution were compared to the operative findings. Four cases of false positive inferior vena caval involvement on preoperative venacavograms performed and interpreted elsewhere were identified. In 3 of these cases a repeat preoperative inferior venacavogram performed at this hospital made the correct diagnosis. In the remaining case an inferior venacavogram was not repeated but no tumor was found at operation. One patient who did not undergo an operation was believed to have vena caval involvement by computerized tomography but venacavography was negative. Reasons for the false positive studies included suboptimal technique and misinterpretation of normal flow defects. Our technique for venacavography is presented. The importance of satisfactory preoperative radiological studies is stressed.

Carcinoma, Renal Cell↗

PubMed1990

Utility of Tc-99m DTPA aerosol inhalation scans following perfusion lung scans in the diagnosis of pulmonary embolism.

The authors report their experience with the use of Tc-99m DTPA aerosol following a perfusion lung scan. The study includes 422 consecutive patients with suspected pulmonary embolism. The final diagnosis was determined by (a) clinical follow-up for 2 months or more, (b) pulmonary angiography, or (c) autopsy. There were 79 patients (19%) who had a normal or near-normal perfusion study and in whom no aerosol study was required. Interpretation groups were classified and divided as follows: Normal or low probability 281 (66.5%) High probability 75 (18.0%) Intermediate 60 (14.0%) Technically inadequate 6 (1.5%) There was autopsy or angiographic confirmation of 72 patient studies with confirmation of the scan diagnosis in 29 of 31 classified as normal or low probability and 24 of 25 classified as high probability. The background perfusion albumin activity was not computer-subtracted from the combined aerosol-perfusion image. Technical improvements included the use of eight standard views for both the perfusion and the subsequent aerosol scan, and the use of 75 mCi (2,775 MBq) of Tc-99m DTPA in the radioaerosol nebulizer. This allowed for easy accumulation of more than three times the count rate in a posterior aerosol image when compared with the previous posterior perfusion image. The authors' experience shows that the perfusion lung scan followed by this radioaerosol technique is a reliable means to evaluate suspected pulmonary embolism.

Administration, Inhalation↗

PubMed1990

Experience with new retrieval forceps for foreign body removal in the vascular, urinary, and biliary systems.

A new type of foreign body retrieval forceps recently has become available. It consists of single- or multiple-tooth forceps mounted on a flexible stainless steel 0.038-inch shaft. The authors have successfully used this device in the vascular system (three cases), in the urinary tract (seven cases), and in the biliary system (two cases) without complications. Foreign bodies removed include a catheter fragment, angiographic guide wire, detachable balloon, stone retrieval basket, and various stents. All the procedures were performed quickly and without difficulty. For the authors, these forceps have become the first choice in many retrieval situations.

Adolescent↗

PubMed1990

New balloon-through-balloon angioplasty technique for the treatment of segmental lesions.

A new balloon catheter on a wire that can be passed through standard 5- and 7-F angioplasty catheters recently became available. This capability allowed the authors to dilate segmental arterial lesions in which different balloon sizes were required without multiple catheter exchanges. Six patients were successfully treated with this technique, without complications.

Angiography↗

PubMed1990

Autoradiology: patient heal thyself.

All in all, our program has been a great success, endorsed by everyone from patients to health care providers and hospital administrators. The PPP will revolutionize diagnostic and interventional radiologic procedures and will free the radiologist to perform more critical maneuvers--the out-of-department lunch, the extended afternoon off, and perfection of the golf swing.

Humans↗