The effect of branded versus standardized e-cigarette packaging and device designs: an experimental study of youth interest in vaping products

OBJECTIVES

Standardized ('plain') packaging is effective in reducing the appeal of cigarettes among young people. This study examined the impact of plain packaging and brand imagery on interest in trying e-cigarettes among youth.

STUDY DESIGN

Experimental design.

METHODS

Two online experiments were conducted in February 2020 as part of the ITC Youth Tobacco & Vaping Survey, conducted with 13,624 16- to 19-year-olds in Canada, England, and the USA. In the between-group Experiment 1, participants were randomized to view a set of 3 e-cigarette brands, in either their original external packaging ('branded' condition) or standardized olive-green packaging ('standardized' condition), and asked to select the product they would be most interested in trying. The within-group Experiment 2 examined brand imagery directly on devices, including potential differences in appeal among subgroups. Each participant viewed 4 pod-style e-cigarette devices: one 'plain' and 3 in colourful 'skins'. Logistic regression models were conducted to test the effect of condition, adjusting for demographics, smoking and vaping status.

RESULTS

In Experiment 1, participants in the 'standardized' packaging condition were significantly more likely to indicate 'I have no interest in trying any of these products' (72.3%) than those in the 'branded' condition (66.9%, AOR 1.45, 95% CI 1.33-1.59). Experiment 2 results indicated differences in e-cigarette appeal by sex in the selection of male- and female-oriented designs, and by cannabis use for a Rastafarian-themed design.

CONCLUSIONS

Brand imagery on e-cigarettes can target products to specific subgroups. Removal of imagery, in the form of standardized packaging, has the potential to reduce interest in trying e-cigarettes among young people.

Micro-CT and FE-SEM enamel analyses of calcium-based agent application after bleaching

OBJECTIVES

The objective of the present study is to evaluate the effects of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on bleached enamel.

MATERIALS AND METHODS

A bleaching agent (35% hydrogen peroxide) was applied, 4 × 8 min on premolar teeth (n = 8). A CPP-ACP paste was applied for 7 days. Prior and post-treatment, microtomography images were obtained and 3D regions of interest (ROIs) were selected, from outer enamel, extending to 110.2-μm depth. CT parameters of structure: thickness (St.Th), separation (St.Sp), and fragmentation index (Fr.I.) were calculated for each (ROI). Data was submitted to paired t tests at a 95% confidence level. The samples were evaluated at 3000 to 100,000 magnification. Quantitative analysis of enamel mineral content was also determined by SEM EDX.

RESULTS

There was a significant increase in structure thickness and calcium content. The phosphorus content increased after bleaching. There was also a decreased separation and fragmentation index on the outer enamel to a depth of 56.2 μm (p < 0.05). There were no changes at 110.2-μm depth for the bleaching CPP-ACP association. A covering layer and decreased spaces between the hydroxyapatite crystals appeared around the enamel prisms, 7 days after the CPP-ACP application.

CONCLUSIONS

The application of a CPP-ACP provides a compact structure on the enamel's outer surface, for 7 days, due to calcium deposition. CT parameters seem to be a useful tool for mineralizing and remineralizing future studies.

CLINICAL RELEVANCE

CPP-ACP neutralizes any adverse effects on enamel surface when applied during a week after bleaching and minimizes any side effects of the bleaching treatment due to a more compact structure.

Bond strength of hard chairside reline resins to a rapid polymerizing denture base resin before and after thermal cycling

PURPOSE

This study assessed the shear bond strength of 4 hard chairside reline resins (Kooliner, Tokuso Rebase Fast, Duraliner II, Ufi Gel Hard) to a rapid polymerizing denture base resin (QC-20) processed using 2 polymerization cycles (A or B), before and after thermal cycling.

MATERIALS AND METHODS

Cylinders (3.5 mm x 5.0 mm) of the reline resins were bonded to cylinders of QC-20 polymerized using cycle A (boiling water-20 minutes) or B (boiling water; remove heat-20 minutes; boiling water-20 minutes). For each reline resin/polymerization cycle combination, 10 specimens (groups CAt e CBt) were thermally cycled (5 and 55 degrees C; dwell time 30 seconds; 2,000 cycles); the other 10 were tested without thermal cycling (groups CAwt ad CBwt). Shear bond tests (0.5 mm/min) were performed on the specimens and the failure mode was assessed. Data were analyzed by 3-way ANOVA and Newman-Keuls post-hoc test (alpha=.05).

RESULTS

QC-20 resin demonstrated the lowest bond strengths among the reline materials (P<.05) and mainly failed cohesively. Overall, the bond strength of the hard chairside reline resins were similar (10.09+/-1.40 to 15.17+/-1.73 MPa) and most of the failures were adhesive/cohesive (mixed mode). However, Ufi Gel Hard bonded to QC-20 polymerized using cycle A and not thermally cycled showed the highest bond strength (P<.001). When Tokuso Rebase Fast and Duraliner II were bonded to QC-20 resin polymerized using cycle A, the bond strength was increased (P=.043) after thermal cycling.

CONCLUSIONS

QC-20 displayed the lowest bond strength values in all groups. In general, the bond strengths of the hard chairside reline resins were comparable and not affected by polymerization cycle of QC-20 resin and thermal cycling.

Management of aberrant subclavian artery aneurysms

An aberrant subclavian artery is the most common congenital anomaly of the aortic arch. Aneurysms of these vessels are relatively rare lesions. A high clinical suspicion must be maintained in patients with an abnormal mediastinum on chest X-ray, especially in patients with dysphagia, dyspnea, or upper extremity ischemic symptoms not otherwise explained. Potentially disastrous complications, including spontaneous rupture and perforation into the esophagus may occur, and are invariably fatal. We present the case of an 1 asymptomatic 72-year-old male with an aberrant right c subclavian artery aneurysm presenting as a mediastinal mass on routine chest X-ray. Repair was by aneurysmectomy through a left thoracotomy and right common carotid artery to subclavian artery bypass via median sternotomy with resolution of his symptoms. We reviewed 74 cases in the English literature to February 1998. The pertinent anatomy is discussed and trends in surgical treatment are identified. Recent agreement on the surgical approach and choice of revascularization appears to exist, but advances in diagnostic and interventional radiologic capabilities have increased the number of asymptomatic lesions encountered and may alter the treatment of this lesion in the near future.

A comparison of the reliability of two techniques of left double-lumen tube bronchial cuff inflation in producing water-tight seal of the left mainstem bronchus

A double-lumen endobronchial tube (DLT) bronchial cuff inflation technique that reliably ensures effective water-tight isolation of the two lungs has not been determined. In this study, 20 patients undergoing thoracic surgery requiring a left DLT had the bronchial cuff of the DLT inflated by one of two techniques. In Group 1, the cuff was inflated to produce an air-tight seal of the left bronchus using the underwater seal technique. In Group 2, the cuff was inflated to a pressure of 25 cm H2O. After bronchial cuff inflation in both groups, water-tight bronchial seal was tested by instilling 2 mL of 0.01% methylene blue (MB) above the bronchial cuff of the DLT. Fifteen minutes later, fiberoptic bronchoscopy was performed via the bronchial lumen of the DLT to determine whether MB had seeped past the bronchial cuff. Cuff volume was 0.75+/-0.64 and 0.76+/-0.46 mL, cuff pressure was 30.1+/-27.0 and 25.0+/-0.0 cm H2O (mean+/-SD), and MB was positively identified in two and five patients in Groups 1 and 2, respectively. The difference in cuff volume and pressure and the higher MB seepage in Group 2 compared with Group 1 was not statistically significant. In both groups, MB seepage occurred only when the bronchial cuff volume was <1 mL and when the patients were positioned in the left lateral decubitus position. These findings suggest that the risk of aspiration is greatest when the DLT is positioned in the dependent lung and when the bronchial cuff volume is <1 mL.

IMPLICATIONS

Water-tight sealing of the left bronchus by DLT bronchial cuff was tested after cuff inflation using two different techniques. Neither air-tight bronchial seal nor cuff pressure of 25 cm H2O guaranteed protection against aspiration. The risk of aspiration was greatest when the DLT was positioned in the dependent lung and when the bronchial cuff volume was < 1 mL.

Solitary fibrous tumors: a series of lesions, some in unusual sites

Solitary fibrous tumor (SFT) is a rare neoplasm that, in addition to its classic presentation as a pleural-based mass, can also be encountered in unusual sites. The main difficulty in making the diagnosis of SFTs results from the unfamiliarity with its diverse clinical and pathologic features. This series of SFTs, some with unusual clinicopathologic presentation, included nine women and two men, ranging in age from 28 years to 74 years (five in pleura, one in lung parenchyma, one in breast, and four in mediastinum). The tumors were locally excised in eight cases and were resected along with portions of lung parenchyma in three. A panel of immunohistochemical stains was used to characterize these tumors. They were all vimentin-positive and, with the exception of one case, CD34-positive. Tumors were negative with antibodies directed against cytokeratin, factor VIII-related antigen, S-100 protein, muscle-specific actin, and smooth-muscle actin. Various diagnoses were initially rendered for these clinically and pathologically diverse lesions by the examining pathologists. Awareness of the various gross and microscopic patterns of these tumors, the possibility of occurring in unusual sites, and the use of immunohistochemical stains, particularly CD34, should eliminate most of the difficulties in arriving at a correct diagnosis. One patient died of metastatic breast cancer; all other patients were alive and well with a median follow-up of 17 months.

Endoscopic ultrasound for staging esophageal cancer, with or without dilation, is clinically important and safe

BACKGROUND

To fully evaluate patients with esophageal cancer by endoscopic ultrasonography (EUS), the transducer must pass through the entire tumor to the cardia to scan the celiac axis. Dilation may be necessary. Published information suggests that dilation with EUS carries a sizeable risk.

METHODS

In order to assess the complication rate associated with dilation prior to EUS in patients with esophageal cancer and the clinical significance of dilation for complete EUS staging, we reviewed the records of all patients who had undergone EUS for esophageal cancer.

RESULTS

Sixty-three patients underwent EUS staging of esophageal cancer. Thirty-nine (62%) had lesions through which the EUS scope was passable (Group I). Ten (16%) patients (Group II) had lesions through which an EUS scope (diameter 13 mm) was unable to pass even after dilation. Fourteen patients (22%) had lesions that were dilated to allow passage of the EUS scope (Group III). All patients in Groups II and III had confirmation of EUS staging by CT and/or surgery. In Group II, five patients had tumors defined as T4 (50%) and five as T3 (50%). In Group III, nine (64%) had T4 tumors, four (29%) had T3, and one (7.7%) had T2. No complications were encountered in any group.

CONCLUSION

EUS, either alone or after dilation, is a safe procedure and the complete EUS examination with celiac node visualization adds prognostically significant information.

Diagnosis of aortic dissection: value of helical CT with multiplanar reformation and three-dimensional rendering

OBJECTIVE

Twenty-three patients with suspected aortic dissection were evaluated in this preliminary study of helical CT to determine the usefulness of axial sections, multiplanar reformation, and three-dimensional (3D) rendering in assessing the presence of dissection and the extent of intimal flap.

MATERIALS AND METHODS

Patients were referred for helical CT scanning because of chest pain or an abnormal chest radiograph. Scans were performed during bolus injection of nonionic contrast material at 2.0-2.5 ml/sec using a mean scan delay of 47 sec. Axial scans with 5-mm collimation were obtained in all patients. They extended from the great vessels to the distal thoracic aorta just above the hiatus. Delayed nonhelical sections were obtained through the upper abdomen. Multiplanar reformations and 3D models were reconstructed from the helical data in 13 patients and were compared to axial sections in 7 patients who proved to have documented dissection. The efficacy of CT was determined using surgery, angiography, or clinical outcome to establish the diagnosis.

RESULTS

Of the 23 patients studied, axial sections resulted in 15 true-negative, 7 true-positive, and 1 false-positive interpretation. In three of seven patients with dissection, it was difficult to determine the extent of the intimal flap on axial sections; multiplanar reformation or 3D views clarified the relevant anatomy in all 3 cases. Among the 3D display methods, ray-sum projection views were superior to surface model or maximum-intensity-projection views.

CONCLUSION

If studies of larger numbers of patients confirm our preliminary findings, multiplanar reformation and 3D rendering of helical CT scans will be a valuable addition to axial display of CT studies used to detect aortic dissection and to determine the extent of the intimal flap.

Abdominal aortic aneurysms: findings on three-dimensional display of helical CT data

Excellent vascular opacification, reduction in misregistration artifacts, and the option of reconstructing overlapping scans from which three-dimensional (3D) models of the abdominal vessels may be rendered are among the benefits of helical CT [1-4]. The purpose of this essay is to illustrate the findings of 3D rendering of helical CT data in patients with abdominal aortic aneurysms.

Abdominal aortic aneurysms: evaluation with variable-collimation helical CT and overlapping reconstruction

PURPOSE

To determine the value of variable collimation and overlapping reconstruction in helical computed tomography (CT) to evaluate abdominal aortic aneurysm.

MATERIALS AND METHODS

Twenty-three patients (15 men and eight women, aged 59-85 years) underwent helical CT scanning, nine with fixed 5-mm collimation and 14 with 3- and 7-mm collimation combined. The ability to visualize main and accessory renal arteries, detect stenoses, and determine aneurysm extent were evaluated.

RESULTS

Extent of aneurysm was accurately determined in 17 of 23 cases without overlapping sections; failure to detect ancillary findings such as accessory arteries or stenosis occurred in nine of these cases. With overlapping sections, determination of aneurysm extent improved to 19 of 23 cases and ancillary errors were reduced to four. Five errors occurred with fixed collimation and three errors with variable collimation.

CONCLUSION

Overlapping, variable-collimation helical CT allows for a more complete evaluation of abdominal aortic aneurysms than does nonoverlapping, fixed-collimation CT.

Preoperative assessment of abdominal aortic aneurysm: the value of helical and three-dimensional computed tomography

PURPOSE

The purpose of this study was to evaluate the utility of helical computed tomography (CT) in the preoperative assessment of abdominal aortic aneurysms (AAA) and to compare its accuracy with aortography and operative findings.

METHODS

Thirty-two patients with suspected AAA were evaluated by helical CT with either 5 mm collimation (slice thickness) or a combination of 3 mm collimation through the renal and mesenteric arteries and 7 mm collimation through the remainder of the AAA. Three-dimensional reconstructions were performed with use of three different techniques, and results were compared with aortography and surgery.

RESULTS

Twenty-five patients were found to have an aneurysm, and 19 subsequently underwent surgery. Standard angiography was also performed in 13. The location, size, and extent of the aneurysm, as well as the wall calcification and intraaneurysmal thrombus, were well depicted with helical CT. The visceral aortic branches, including the detection of renal artery stenosis and accessory renal arteries, were consistently seen with the 3 mm/7 mm collimation protocol and three-dimensional reconstruction.

CONCLUSION

Helical CT with three-dimensional display of the aorta and its branches combines the advantages of conventional CT imaging and aortography. This technique appears to provide comprehensive preoperative evaluation of AAA.

Pedicled muscle flaps in the management of infected aortofemoral grafts

Graft infection, although uncommon, is a serious complication of reconstructive vascular surgery, associated with a high mortality and limb loss in a large percentage of the survivors. Although débridement and drainage, specific systemic antibiotics, removal of the entire infected graft and revascularization by extra-anatomic bypass are the general principles of management, this technique has its limitations and in certain circumstances is not feasible. The use of well-vascularized autogenous tissue as coverage of infected grafts has been successful in the lower extremities, with graft and limb salvage, but not when the infection extends above the inguinal ligament. Instances where the infection at the inguinal area extends retrograde along the limb of the aortofemoral graft represent a greater therapeutic challenge. In two instances, a dual muscle flap was used successfully to cover the exposed prosthesis after complete débridement of the perigraft granulation tissue. Sartorius and rectus femoris muscles, with their blood supply, were mobilized and rotated to cover the distal anastomosis and the retroperitoneally exposed graft respectively, with primary wound closure. All flaps survived and the patent grafts were salvaged. There was no long-term functional deficit from the transposition of these muscles. Pedicled muscle flaps appear to be a well-tolerated method of achieving autogenous tissue coverage of an infected graft in the groin, and retroperitoneal portions and should be considered a satisfactory alternative when the traditional methods of management cannot be applied.

Salmonella aortitis. A report of a successfully treated case with a comprehensive review of the literature

A successfully treated case of Salmonella infection of the thoracic aorta is described. Salmonella enteritidis was isolated from blood cultures and from operative cultures of the aorta. Computed tomography suggested the site of infection, and the resection of the thoracic aortic aneurysm with specific antibiotic therapy resulted in a satisfactory outcome. Although once invariably fatal, improved diagnostic roentgenographic techniques, more potent antibiotics, and surgical advances have resulted in at least 45 reported survivors over the last 15 years. The pathogenesis, clinical and laboratory characteristics, and the treatment of aortitis due to Salmonella species are reviewed in 98 cases reported in the English-language literature since 1948. Early diagnosis and a combination of prompt surgical intervention and antibiotic therapy are essential for survival.

Infected aortic aneurysms: CT diagnosis

Infected aortic aneurysms are uncommon but important because they can lead to uncontrolled sepsis and/or aortic rupture. Symptoms are frequently minimal during the early stages and a high index of suspicion is essential to make the diagnosis. The surgical literature suggests that survival is markedly improved by a prompt diagnosis and aggressive surgical intervention. Our recent experience with 5 cases who underwent arteriography and/or computed tomography (CT) prior to surgery was reviewed and these diagnostic methods compared. Traditionally, arteriography has been considered indispensable in the evaluation of infected aortic aneurysms but the aneurysm lumen must reach a certain size before it can be detected and, even then, the extraluminal component may be underestimated. CT, with contrast enhancement, was more sensitive in the early stages of the disease and provided a more complete depiction of the anatomic abnormalities. Mural enhancement preceded the increase in the aortic lumen with disruption of aortic wall calcification. An earlier and more accurate diagnosis can be provided by CT than by angiography without the disadvantages of its invasiveness and cost.

Gadolinium-enhanced magnitude contrast MR angiography of popliteal and tibial arteries

To evaluate the efficacy of gadopentetate dimeglumine in MR angiography of the lower extremities, a flow phantom, seven healthy volunteers, and seven patients with peripheral vascular disease were studied with a magnitude contrast (MC) technique. The combination of an MC rephase-dephase gradient-refocused-echo pulse sequence, a 40-cm-long transmit-receive coil, and intravenous administration of a bolus of gadopentetate dimeglumine improved MR angiographic quality in the phantom, volunteers, and patients. Gadolinium enhancement decreased deleterious saturation effects and improved images of the popliteal and tibioperoneal arteries in the volunteers and patients. However, in some cases, venous overlap, imaging artifacts, and suboptimal visualization of subtle lesions limited interpretation. The authors conclude that gadolinium enhancement combined with an MC subtraction pulse sequence appreciably improves MR angiography of lower extremity arteries.

Infected aortic aneurysms. A changing entity

Infected (mycotic) aortic aneurysms are infrequent and, without surgical intervention, usually lead to uncontrolled sepsis or catastrophic hemorrhage. Symptoms are frequently absent or non-specific during the early stages, and a high index of suspicion is essential to make the diagnosis. Surgery performed after rupture carries high morbidity and mortality rates. Bacterial endocarditis with streptococcus pyogenes was the most common cause of infected aortic aneurysm in the pre-antibiotic era. Today, arterial trauma due to iatrogenic manipulation and depressed immunocompetence have become more common risk factors. Staphylococcus aureus and Salmonella are the most frequent bacteria identified. The authors' recent experience in six patients with infected aortic aneurysms who underwent arteriography and computed tomography was reviewed and these diagnostic methods compared. Computed tomography was found to be more sensitive in the diagnosis of the early stages of the disease, allowing for follow-up by serial scans in a noninvasive and less costly manner. Successful treatment, in four of these patients, was accomplished by aneurysmal resection and extra-anatomic bypass or in situ prosthetic reconstruction. A higher clinical awareness of this disease, leading to early computed tomography evaluation and prompt surgical intervention under appropriate and intensive antibiotic therapy, appears to offer the best chance of survival in patients with this difficult condition.

Assessment of major venous anomalies by computerized tomography

Congenital anomalies of major venous structures are not common but their identification and relative position, particularly in relation to an abdominal aortic aneurysm, are of significant value in planning and conducting aortic operations. Computed tomography (CT) has become a common method of preoperative evaluation of aortic disease. Its reliability in providing accurate information regarding aneurysmal size, configuration, and extension, as well as the presence of intraluminal thrombus and involvement of the renal and iliac arteries, has been demonstrated. Simultaneous visualization of the major adjacent venous structures with the use of contrast enhancement is obtained, but anatomic variants can be overlooked because they are commonly subtle and considered incidental. The preoperative diagnosis of these venous abnormalities is significant to the vascular surgeon. Such information can be accurately and reliably acquired with the present CT techniques without the need for further diagnostic studies.

MR and CT findings in pulmonary artery sarcoma

Pulmonary artery sarcomas are a rare and frequently forgotten cause of pulmonary artery occlusion. We present a case report that details magnetic resonance and new CT findings, which may help establish early diagnosis of this infrequently encountered tumor.

Improved identification of renal arteries in patients with aortic aneurysms by means of high-resolution computed tomography

Suprarenal extension of abdominal aortic aneurysms (AAAs) has been reported to be present in less than 10% of patients. Its preoperative demonstration is of value in planning the aneurysm repair; however, the most appropriate radiologic method of assessment remains controversial. Although many practitioners advocate angiography, recent advances in noninvasive techniques challenge this approach. To determine the optimal method of assessment, a retrospective study of CT, ultrasonography, and angiography was undertaken in a group of 101 patients with AAA. Conventional CT was used in all patients and high-resolution CT through the region of the renal vein was used in 45 of these patients. Ultrasonography was used in 27 patients and angiography in 23. Conventional CT detected the renal artery origins in 76% of the cases--results that improved to 98% when thin-section high-resolution CT was used. These improvements in CT make the delineation of the relationship of the renal arteries to the aortic aneurysms almost as accurate as angiography at approximately half the cost. Its accuracy, safety, and cost effectiveness make CT the modality of choice in the preoperative assessment of suprarenal aortic aneurysms.

An improved Leather valve cutter for in situ saphenous vein arterial bypass

The Leather valve cutter allows the in situ saphenous vein below-knee arterial bypass to be used with smaller veins and is faster than previous methods. A persistent problem with the valve cutter, however, is its tendency to separate from the Fogarty catheter as it is being pulled through the saphenous vein. An improved valve cutter which can be easily constructed and prevents accidental dislodgement is described herein. It has been used successfully in six patients without complications.

Mediastinal tracheostomy

Upper airway obstruction in primary or recurrent carcinomas of the head and neck extending into the mediastinum may demand surgical intervention despite severe technical difficulties in patients with tumors previously considered inoperable. In fact, many of these tumors may be operable and some perhaps curable. A technique has been developed based in part on our experience with previously described procedures. A preliminary sternal split is used to demonstrate the extent of the mediastinal involvement as well as to provide enhanced exposure and proximal control of the great vessels. The pectoralis major muscle is used with a generous flap of overlying skin comprising nearly half of the anterior portion of the chest. A tracheostomy is then created in a fashion similar to the placement of a cardiac valvular prosthesis by creating a circular defect in the pectoralis major flap and suturing it to the tracheal remnant. This technique offers a reasonably safe and reliable means of creating a low anterior mediastinal tracheostomy for tumors previously considered inoperable. The preliminary sternal split makes the procedure safer and easier to perform, and the use of a very large pectoralis major island flap allows for reliable closure of the resulting mediastinal and sternal defects.

Pre-operative evaluation of abdominal aortic aneurysms: ultrasound or computed tomography?

Evaluation of aortic aneurysms by ultrasound (US) or computed tomography (CT) is now commonplace and their use often reflects personal preferences given their similar diagnostic accuracy. Knowledge of anatomic details may be very helpful in the planning of the surgical procedure. Involvement of the supra-renal aorta, relative position of the renal arteries, intra-aneurysmal thrombus, and extension to the iliac arteries were retrospectively evaluated by both techniques to determine which modality was more valuable in the preoperative evaluation of abdominal aortic aneurysms. A group of 58 patients was reviewed. An infra-renal aortic aneurysm was identified in all instances by both methods. The supra-renal aorta was always well visualized by CT but not by US. The origin of at least one renal artery was seen in only 11% of the cases by US but in 100% by CT. CT demonstrated the left renal vein in all cases, while only 41% were demonstrated by US. Intra-aneurysmal thrombus was depicted by both methods but its distribution within the sac and the characteristics of the thrombus were apparent on CT but not on US. Aneurysmal involvement of the iliac arteries was present in 19% of the patients. CT detected all cases but only 14% were demonstrated by US. Both methods accurately diagnose abdominal aortic aneurysms. Supplementary data regarding proximal and distal extension, characteristics of the thrombus, relationship to the renal vessels, and adjacent major veins can be obtained by CT and usually not by US. This information is of value in the planning and execution of the indicated surgical procedure.

Metastatic cancer. A relative contraindication to vena cava filter placement

From October 1979 to November 1984, 41 patients underwent placement of vena cava filters for prevention of pulmonary emboli. After filter placement, no pulmonary emboli were documented. No patient died due to filter placement. However, 20 of these 41 patients are dead. Eighteen deaths were caused by cancer. Ten (24%) patients died within 2 months of filter placement. Five (12%) patients died prior to hospital discharge. All ten of these patients had known, widely metastatic cancer. Among the ten patients who died more than 2 months after filter placement, six had well-differentiated, slow growing tumors. Only three of these patients had brain metastases. Among the 21 survivors only two suffered from cancer. Strict adherence to accepted indications for vena cava filter placement required operative procedures on a small but significant number of patients who demonstrated no significant improvement in quality of life or time out of hospital. Filter placement in patients with aggressive cancers and proven metastases should be performed only after analysis of predicted survival and after detailed discussions with patients and referring physicians. Filter placement in patients with aggressive metastatic cancer may cause discomfort, risk, and expense with little hope for improvement of hospital course, longevity, or quality of life.

Present status of abdominal aorta imaging by computed tomography

A seven-year experience with CT scanning in the diagnosis and evaluation of abdominal aortic aneurysms is reviewed. Two hundred twenty-six patients with suspected abdominal aortic aneurysms were studied, 12 being acute situations with possible rupture. In 15 no aortic pathology was seen. The diagnosis of an aneurysm regardless of its location was made in all instances and confirmed by other techniques and/or surgery. Location, size, extension and presence of thrombus were well delineated. Aortic rupture or leakage was demonstrated when present. Unsuspected involvement of the thoracic aorta, as well as the iliac arteries was shown. CT scanning is a technique that can safely, easily and accurately be used in the diagnosis of, follow-up and extension of aneurysmal disease regardless of its location or clinical situation and compares favorably with any other available technology.

Non-invasive evaluation of thoracic aneurysms

Sixty-six patients with possible abnormalities of the thoracic aorta were examined by CT and the data compared with standard chest radiographs, angiography and, in most, with the surgical findings. Using contrast enhancement computed tomography was able to evaluate and differentiate between a tortuous aorta, an atherosclerotic aneurysm, and aortic dissection and extra-aortic masses. Distinguishing pathological features are discussed. In aortic dissections angiography may be necessary to delineate the site of the intimal tear. Long term follow-up of aortic dissections, especially Type III, is best done by CT. Aneurysmal rupture or leakage, as well as extension into the abdominal aorta, can easily be ascertained by this method.

Echocardiographic features of traumatic disruption of the aortic valve

The echocardiographic findings are presented of a patient who had evidence of aortic regurgitation one year after blunt trauma to the chest. Combined M-mode and 2-D imaging showed features suggestive of disruption of the posterior aortic leaflet, subsequently confirmed at operation, in the absence of infective endocarditis. Diagnosis of this uncommon cause of aortic regurgitation, heretofore confirmed only by direct visualization, may be made preoperatively by echocardiography.

Diagnosis of abdominal aortic aneurysms

An abdominal aortic aneurysm can often be diagnosed on the basis of physical examination alone. Radiographic demonstration of calcification outlining the aneurysmal wall is the simplest way to confirm the diagnosis but is feasible in only about 50 percent of cases. Aortography carries a potential risk and often gives false-negative results. Ultrasonography and CT scanning are the safest and most reliable methods used in screening for abdominal aortic aneurysms.

Severe aortic regurgitation from systemic hypertension (without aortic dissection) requiring aortic valve replacement: analysis of four patients

Clinical and morphologic observations are described in four patients who had severe aortic regurgitation from severe systemic hypertension unassociated with aortic dissection; each patient underwent aortic valve replacement. Although aortic regurgitation of minimal or mild degree is well recognized to occur in patients with systemic hypertension, severe degrees of aortic regurgitation are rare in such patients; aortic valve replacement in such patients has not previously been reported. Why these four patient had such severe aortic regurgitation was not determined. Although systemic hypertension is rarely a cause, it nevertheless must be added to the list of causes of severe pure aortic regurgitation.

Abdominal aortic aneurysms: diagnostic review and new technique

A new technique of computed tomography (CT) applied to the diagnosis of abdominal aortic aneurysms is described, and the experience in 58 patients is reviewed. In all instances the abdominal aorta was clearly demonstrated, even when wall calcification was absent. A series of 37 patients with abdominal aortic aneurysm underwent evaluation by physical examination, abdominal roentgenograms, and ultrasonic and CT scanning. Measurements of the transverse diameter at the point of maximal dilatation were compared with the measurements made at operation. CT not only confirmed the diagnosis in all patients but the measurements obtained by this technique were the most accurate, correlating extremely well with the true dimensions of the aneurysm. The addition of contrast enhancement to CT scanning allowed clear delineation of the aortic lumen and intraaneurysmal thrombus, not possible with any other method, including ultrasonography. The technique appears useful as a screening procedure and in the differential diagnosis of a tortuous abdominal aorta. Patients with a small aortic dilatation can be followed accurately by scanning.

Ultrasonography and CT scanning: a comparative study of abdominal aortic aneurysms

CT scanning has been successfully used in the evaluation of the abdominal aorta in over 70 patients. Half of this group, with abdominal aneurysms, was also studied by ultrasonography and the results compared. Both techniques proved equally reliable in the diagnosis of this entity. Closer correlation to the aneurysmal diameter measured at surgery was obtained by CT scanning; underestimation of size by ultrasonography was a frequent finding. Aortic lumen and intra-aneurysmal thrombus were also more clearly demonstrated by CT when contrast enhancement was added. Evaluation of aneurysmal length is done more effectively by ultrasonography although sagittal reconstruction by CT has been now attempted.

Severe aortic regurgitation secondary to idiopathic aortitis

Clinical and morphologic features are described in two relatively young adults with aortic regurgitation secondary to chronic aortitis. The regurgitation in each was severe enough to require aortic valve replacement. Both patients had normochromic, normocytic anemia, considerable weight loss despite congestive cardiac failure, and negative serologic tests for syphilis. These systemic manifestations in association with the aortitis suggest that both had Takayasu's arteritis. In addition, one patient had total occlusion at the origin of one subclavian artery (classic pulseless disease). Takayasu's arteritis must be added to the list of causes of severe aortic regurgitation.

ACTA scanning in the diagnosis of abdominal aortic aneurysms

The presently available diagnostic methods for abdominal aortic aneurysms are reviewed. The application of ACTA scanning for this diagnosis in 35 patients is described. In all cases the presence of an aortic aneurysm was confirmed, even when calcification of its wall was absent. Contrast enhancement demonstrated that aortic lumen not otherwise visualized. In some instances the iliac arteries were clearly seen and more readily so when calcified. Estimates of aneurysm size were compared with measurements taken at surgery with a relatively close correlation. This technique seems to be useful in the differential diagnosis with tortuous abdominal aorta or as a screening procedure. Patients with minimal ectasia of the aorta can be followed by scanning. The planned addition of shorter scanning times and sagital scans with allow the fast evaluation of the longitudinal dimension of the abdominal aortic aneurysm, which is difficult to obtain with the present technique.

Late follow-up of ball-valve prostheses in the descending thoracic aorta

Clincal and hemodynamic observations are reported in a group of five patients with free aortic regurgitation treated with insertion of a ball valve prosthesis in the descending aorta. Long-term follow-up ranging from 13 to 23 years illustrates the durability and biocompatibility of the valve and the validity of the concept that a moving prosthesis can function for indefinitely long periods of time. The prolonged survival of these patients at a normal level of activity without congestive failure is strong evidence of the efficacy of the prosthesis even though it did not entirely control all of the aortic insufficiency. All patients showed remarkable improvement of their symptoms from 11 to 21 years after surgery. Four of them have required complete correction of the aortic insufficiency with one postoperative death due to low output syndrome. The valves which have remained in place after insertion of a subcoronary valve are functioning well for 3 to 6 years. There was no evidence of hemolysis, valve malfunction, ball variance, or thrombbosis in any of these patients. The evolution of the technique made it possible to minimize complications which, it should be pointed out, were usually associated with faulty methods of insertion. These patients would appear to represent the longest period of insertion of any valvular prosthesis.

Computed tomographic evaluation of aortic aneurysms

Applications of computed tomography are being extended from the brain to other body parts. This report describes CT scanning of abdominal and thoracic aortic aneurysms in 30 patients. CT shows greatest promise in abdominal aortic scanning, where reliable identification of the aorta can be achieved even in the absence of enlargement or calcification. However, current limitations prevent visualization of internal detail such as intimal plaques or mural thrombi. Technical advances are described which should have an important bearing on this.

Varicose veins

Varicosities may be due to congenital weakness of the vein walls or valves, or may be secondary to deep thrombophlebitis. The latter leads to loss of valve competency in the communicating veins and transmission of relatively high pressures to the superficial system. Edema, thrombophlebitis and stasis dermatitis are common side effects. Adequate surgical therapy is successful in 90% of cases. Sclerosing agents are of limited use.

Intrapericardial bronchogenic cysts

A rare case of large intrapericardial bronchogenic cyst with superior vena caval obstruction is reported. The cyst was successfully removed and the superior vena cava, which was narrowed by pressure fibrosis and thrombosis, was reconstructed satisfactorily and has maintained patency. In another case a large cyst of the same type without vena caval obstruction was successfully treated surgically. The features of these 2 cases are compared with those of 20 reported cases. The angiographic data in these cases appear to be sufficiently characteristic to suggest the nature of the lesion and the clinical finding of pericarditis early in the course of the disease may also suggest the diagnosis.

Superior vena cava obstruction: a review of the literature and report of 2 cases due to benign intrathoracic tumors

A review of the literature shows an increaseing number of cases of superior vena cava obstruction associated with malignancy and a marked decrease in the number of patients with caval obstruction of benign origin. In contrast to granulomatous diseases and aneurysms of the ascending thoracic aorta, which have decreased, the incidence of benign tumors is essentially unchanged. Clinical features of superior vena cava obstruction in relation to the anatomical site of obstruction and collateral pathways are correlated. Diagnostic approaches, including angiography and technetium scanning are usually definitive in outlining the site of obstruction. Experimental data and the numerous available techniques for surgical correction indicate that an entirely satisfactory procedure is not available for all patients. Methods include the use of venous bypass or Teflon prostheses and the addition of a small arteriovenous fistula proximally. Two new cases of superior caval obstruction due to benign tumor are reported. In 1 patient, who had intrapericardial bronchogenic cyst with fibrotic caval obstruction and thrombosis, a method for caval reconstruction while maintaining venous return to the right atrium is described. The second patient had an intrathoracic thyroid adenoma and caval obstruction without thrombosis.