Venous prosthetic valves. The first step toward an investigation in the canine model.

Bioprosthetic valves were surgically placed in the inferior vena cava of four canines as a first step in the investigation of prosthetic valves for the treatment of nonobstructive chronic venous stasis. Valve patency and thrombus formation involving either the valve or the IVC was evaluated by serial follow-up inferior vena cavagrams in each canine. No thrombus occurred in any of the canines as observed at six months in two canines and eight months in two canines. The ultimate goal of this and other ongoing investigations is to develop a valvular prosthesis which may be placed into the venous system for the management of nonobstructive chronic venous stasis.

Radiographic appearance of the nonabsorbed (unconjugated) and conjugated sodium tyropanoate (Bilopaque) in the bowel.

A series of abdominal radiographs were taken in eight normal volunteers after the ingestion of sodium tyropanoate (Bilopaque). These showed nonabsorbed sodium tyropanoate to have a granular appearance, while the conjugated form had a smooth homogeneous appearance. The appearance of conjugated sodium tyropanoate in the bowel has the same diagnostic significance as conjugated iopanoic acid in the presence of a nonvisualized gallbladder. It indicates that the contrast material has passed through the hepatic ductal system and that there has been an opportunity for the gallbladder to opacify.

Response of an abdominal aortic thrombotic occlusion to local low-dose streptokinase therapy.

Local low-dose streptokinase infusion (5000 to 6000 IU/hr) as compared to systemic streptokinase infusion (loading dose 250,000 IU/hr, maintenance dose 100,000 IU/hr) successfully relieved a total thrombotic abdominal aortic occlusion. No complications of bleeding or distal embolization occurred during streptokinase therapy, which required only 8 days of hospitalization. When seen at 4 months after streptokinase infusion, the patient was still free of symptoms. When no immediate threat of ischemic limb loss exists, streptokinase may offer a promising therapeutic alternative to surgical intervention for patients who represent a poor operative risk.

The validity of normal arteriography in penetrating trauma.

The detection of underlying arterial injury is a major problem in the management of penetrating trauma. Arteriovenous fistula and false aneurysm are late sequelae of unrepaired injuries. The diagnostic accuracy of arteriography in clinically occult injury has not been defined. One hundred and seventy-seven patients with 183 penetrating extremity wounds underwent arteriography followed by operative vessel exploration. Arteriogram/operation correlation demonstrated 36 true-positive, 132 true-negative, 14 false-positive, and one false-negative arteriogram. Arteriography is sufficiency sensitive to exclude the presence of arterial injury in patients with equivocal clinical signs of injury. The radiographic changes are often sublte and diagnostic accuracy demands attention to the details of technique and interpretation. Unequivocal clinical signs of arterial injury and any arteriographic abnormality are indications for operative exploration.

Trauma of occult hydronephrotic kidney.

The occult unilateral hydronephrotic kidney is often discovered during the genitourinary evaluation of patients sustaining blunt abdominal trauma. Few cases have been reported documenting the angiographic, computerized tomography (CT), and ultrasound appearances. Two cases are described which demonstrate that relatively minor trauma can precipitate hematuria and hypovolemic shock. Angiography demonstrated the bleeding site in both cases and was utilized in conjunction with other parameters of clinical assessment to plan initial management. CT and ultrasound proved to be useful noninvasive diagnostic parameters for baseline and follow-up studies in patients undergoing conservative management. They accurately demonstrated the degree of hydronephrosis, residual renal parenchymal, and resolving hematoma.

Metrizamide shuntography for evaluation of shunt malfunction in hydrocephalus.

Ventricular shunts were evaluated by a shuntographic technique using metrizamide for the contrast material and delayed spot films and computed tomography (CT) to evaluate shunt function. Thirty hydrocephalic patients were studied who had clinical presentations of shunt malfunction. Fifty-two shuntograms were obtained; most demonstrated the cause of shunt malfunction. No contrast-related complications resulted from the procedure. Diagnostic accuracy was greatly improved by this method, since both anatomic and functional evaluations could be performed. In patients with normal studies, unnecessary surgery was eliminated; in abnormal shuntograms, the duration of surgery and the likelihood of complications were reduced because the surgeons knew the exact anatomic derangements to be corrected.

Computed tomography of traumatic atlantooccipital dislocation.

Although atlantooccipital dislocation is a well-recognized radiological entity, its computed tomographic (CT) recognition has not been previously described. It is the purpose of this report to show the complementary role of CT in precisely defining the abnormalities in both the coronal and the sagittal reconstruction planes. A case is presented and the literature is reviewed.

Valvular xenografts in the inferior vena cava.

The unsolved problem of valvular incompetence is a common denominator to chronic venous insufficiency. Cardiac experience with tissue valves suggests the potential for their use in more peripheral locations. The current initial work evaluated 22 valvular xenografts placed in the inferior vena cavas of 22 dogs. Patency extended to 28 months in 12 valves. There was a plausible explanation for failure in 8 of the 10 unsuccessful units. Patent valves functioned with minimal pressure gradients at moderate flow with no evidence of pulmonary emboli. Retrograde valvulograms showed acceptable functional competence in six of eight units examined despite autopsy evidence of leaflet fibrosis and anatomic incompetence. The study establishes the feasibility of long-term patency of valvular xenografts in the inferior vena cava, but also raises questions concerning design requirements for prosthetic venous valves.

Combined CT metrizamide syringography and needle aspiration of cystic intramedullary spinal cord lesions.

A modified spinal cord puncture technique that was combined with CT metrizamide syringography for the evaluation of potentially cystic spinal cord lesions has been used in 5 patients. This procedure proved to be safe and efficacious in the preoperative differentiation of cystic neoplasms from syringohydromyelia. It also aided in planning a surgical approach by revealing details of the tumor location and/or syrinx dynamics. Spinal cord puncture associated with CT metrizamide syringography has a role in the diagnosis and therapy of patients with cystic spinal cord lesions.

Retrieval of intravascular foreign bodies.

The use of intravascular catheters for diagnostic and therapeutic purposes has resulted in an increased number of foreign body embolizations. The retained foreign body is a potential source of morbidity and mortality. In this communication we describe the different techniques that are used to remove foreign bodies from various locations within the heart or vascular tree. A brief review of the literature concerning the reported complications from retained foreign bodies is made to underline the importance of early percutaneous removal of these fragments.

Embolisation of the external carotid artery in the treatment of carotid cavernous sinus fistulae.

A review of treatment methods used to control carotid cavernous sinus fistulae is presented. Three cases are described in which embolisation of the external carotid artery was done along with intracranial vascular procedures in the management of carotid cavernous fistulae.

The use of the pedal venous pressure (P.V.P.) as a guide in evaluating the patency of venous repairs.

Obstruction of the deep veins by thrombi causes the P.V.P. to become elevated. Monitoring this pressure can serve as an invaluable guide in evaluating the patency or obstruction of venous repairs.

Measurement of pedal venous pressure: a screening procedure in the detection of deep-vein thrombosis and occlusion.

A simple screening procedure is needed to fill the gap between the clinical examination and venography in patients suspected of having deep-vein thrombosis of the lower extremities. The author suggests that measurement of the pedal venous pressure (PVP) be used for this purpose. Measurements of PVP in 86 lower extremities and correlation with venography showed that all extremities with a PVP greater than 35 cm saline were shown to be abnormal on venography, indicating that measurement of PVP can be a satisfactory screening procedure.

Hemorrhage following pelvic fracture controlled by embolization: case report.

This case report demonstrates the value of arterial management with embolization of hemorrhage following pelvic fracture. Surgical ligation and arterial embolization are briefly discussed as treatment modalities.

Guidewire deflector system removal of catheter foreign body retained in the right heart for six months.

A case of successful removal of a catheter foreign body retained in the right atrium for 6 months is presented. The hooked catheter approach was used to retrieve the catheter from the right atrium. Due to the hook configuration of the retrievers, the catheter had to be surgically excised from the common femoral vein. Subsequently a system was developed and used successfully in other cases which eliminates the need for performance of a further surgical procedure to remove successfully the catheter or retrieval device.

The flared mandible sign of the flail mandible.

A useful radiographic finding is described for the diagnosis of a flail mandible. The flail mandible removes forward support for the tongue, which may result in airway obstruction. Immediate radiographic diagnosis allows quick surgical correction of the fractured mandible and relief of the obstruction, decreasing the time during which an endotracheal or tracheostomy tube is needed to keep the airway open.