Acute COVID-19 Pneumonia Unmasking a Large Left Atrial Myxoma

This is a case of acute coronavirus disease 2019 pneumonia that revealed an incidental large atrial myxoma with obstructive physiology that ultimately required emergent treatment with a definitive atriotomy and resection of the underlying myxoma.

Who needs their descending thoracic aorta anyway? Extra-anatomic bypass for aorto-bronchial fistula after TEVAR

BACKGROUND

Aortobronchial fistula after TEVAR remains a vexing clinical problem associated with high mortality. Although a combination of endovascular and open surgical strategies have been reported in managing this pathology, there is as yet no definitive treatment algorithm that can be used for all patients. We discuss our approach to an aortobronchial fistula associated with an overtly infected aortic endograft.

CASE PRESENTATION

A 49-year-old female sustained a traumatic aortic transection 14 years prior, managed by an endovascular stent-graft. Due to persistent endoleak, she underwent open replacement of her descending thoracic aorta 4 years later. Ten years after her open aortic surgery, the patient presented with hemoptysis, and a pseudoaneurysm at her distal aortic suture line was identified on computed tomography, whereupon she underwent placement of an endograft. Eight weeks later, she presented with dyspnea, recurrent hemoptysis, malaise and fever, with clinical and radiographic evidence of an aortobronchial communication and an infected aortic stent-graft. The patient underwent management via a two-stage open surgical approach, constituting an extra-anatomic bypass from her ascending aorta to distal descending aorta and subsequent radical excision of her descending aorta with all associated infected prosthetic material and repair of the airway.

CONCLUSION

Aortobronchial fistula after TEVAR represents a challenging complex clinical scenario. Extra-anatomic aortic bypass followed by radical debridement of all contaminated tissue may provide the best option for durable longer-term outcomes.

Massive Embolism: Knife versus PCI

Pulmonary embolism is the third most common cardiovascular syndrome with an estimated up to 25% of patients presenting with sudden death. For those who survive, a mainstay of management for patients with hemodynamic stability is anticoagulation; however, recommendations and options are rapidly changing for patients with submassive or massive pulmonary embolism with hemodynamic instability. Catheter-based and surgical approaches offer efficacious management options for unstable patients or patients with contraindications to anticoagulation; however, both approaches have inherent benefits and risk. This article seeks to offer a brief review on the recommendations and options for management of pulmonary embolism from both surgical and catheter-based perspectives.

Uniportal VATS Lobectomy and Decortication: Not an Everyday Occurrence

Management of trapped lung with an underlying lung lesion and hydropneumothorax remains controversial. Furthermore, Aspergillus empyema and aspergilloma are rare pathologies for which uniportal video-assisted thoracoscopic (VATS) surgical management remains controversial. We present a young patient referred to our service after recent hospitalization for pneumonia. The patient was found to have a chronic effusion with a right lower lobe cystic parenchymal lesion and was taken to the operating room. The patient underwent right uniportal VATS surgery with evacuation of empyema, total pulmonary decortication, and right lower lobectomy. His postoperative course was unremarkable, and he was discharged home. Postoperative workup demonstrated lymphocyte variant hypereosinophilia. He continues to follow with thoracic surgery at the time of this report and remains asymptomatic. We conclude that uniportal VATS is a most minimally invasive, safe, and efficient approach for management of complex intrathoracic pathology including total pulmonary decortication and lobectomy.

Degenerative Pulmonary Valve Insufficiency in a Patient With a Prior Bentall Procedure

Adult pulmonary valve regurgitation most commonly presents after congenital cardiac surgery, with limited reports of pure degenerative valvular disease. We present a patient who underwent a Bentall procedure for annuloaortic ectasia with severe aortic insufficiency 14 years prior now presenting with degenerative, severe, symptomatic pulmonary valve regurgitation and normal pulmonary pressures. The patient underwent successful valve replacement with a bovine prosthesis. Recovery was unremarkable, and he continues to do well without further cardiac surgical requirements.

P3594Transition from 4th to 5th generation cardiac troponin T: testing patterns, myocardial infarction incident rates, and resource utilization across a multicenter United States regional healthcare system

Background

Several high-sensitivity cardiac troponin (cTn) assays have been cleared by the United States (US) Food and Drug Administration (FDA) for clinical use. Although some of them have been used outside the US for some time, there is limited experience thus far across US sites. Following FDA clearance of the Roche 5th Gen cTnT assay in January 2017, a multicenter US regional healthcare system introduced this more sensitive cTnT assay into clinical practice in September 2018.

Purpose

To examine cTn testing patterns, incidence of acute myocardial infarction (MI), and resource utilization before and after implementation of the 5th Gen cTnT assay across a large US healthcare system.

Methods

Using electronic-health records reporting software (Cogito SlicerDicer, EPIC), administrative data was examined to evaluate the transition (4-months before and after implementation) from the 4th to 5th Gen cTnT assays across 16 hospitals but not the major hub hospital of the system that transitioned at a separate time. Adult patient visits (emergency and hospital encounters), cTnT testing, incidence of chest discomfort and acute MI, and resource utilization, including hospital admissions, were examined during the transition period.

Results

98,558 adult ED patient visits occurred during an 8-month period across 16 hospitals, including 50,485 and 48,073 patient visits before (5/12/18 – 9/11/18) and after (9/12/18 – 1/11/19) implementation of the 5th Gen cTnT assay respectively. cTnT testing occurred in 20% (range 8.9–34.8%) of all ED visits, with testing performed in the absence of chest pain in 54% (range 37–67%) of cases. Acute MI was diagnosed in 5.6% (n=561) of cases using the 4th Gen cTnT assay as compared to 6.6% (n=608) of cases using the 5th Gen cTnT assay (absolute difference 1.0%, 95% CI: 0.32–1.68, p=0.004). Much of the increase in MI diagnoses were in women (2.2% vs. 2.8%, p=0.008). The proportion of ED patients requiring hospital admission did not differ between pre- and post-implementation periods (24.1% vs. 23.6%, p=0.4); however, among the subset of patients with chest pain, fewer admissions occurred post-implementation (17.9% vs. 15.8%, p=0.006). There was no increase in echocardiography (9.3% vs. 8.4%), coronary angiography (2.9% vs. 3.1%), or cardiac consultations (7.3% vs. 7.3%) utilization post-implementation.

Conclusions

Cardiac troponin testing occurs in nearly 20% of ED visits in a large multicenter regional healthcare system. About half of all tests are ordered in the absence of chest pain, with a low MI rate observed among the patients undergoing testing. Following implementation of the 5th Gen cTnT assay, testing rates/patterns remained unchanged, with a small but significant increase in MI diagnoses, primarily due to more women being diagnosed with MI. Fewer ED patients with chest pain required admission. Despite using a more sensitive cTn assay, hospital admissions and resource utilization did not increase post-implementation.

The biography of Mary E. O'Sullivan: an early American headache specialist

The aim of this study was to review the life of Mary E. O'Sullivan and to summarize her important contributions to the study of migraine. Mary E. O'Sullivan underwent extensive training to become a neurologist at a time when only 5% of women in America were physicians. She published five papers on migraine. In a 1936 Journal of the American Medical Association article, she described a patient with ergotamine overuse headache and recommended that daily doses of oral ergotamine should be avoided. Three years later she described migraine as a 'complex' syndrome with multiple causes and multiple cures. Mary E. O'Sullivan, an ambitious female headache specialist of the 1930s, was an early advocate of the use of ergotamine to treat migraine, yet she was one of the first to report ergotamine overuse headache. Although her life was short, her research, knowledge and ambition at a time when women had limited opportunities in medicine have left a mark.

Use of subcutaneous venous access ports to treat refractory ascites

To assess the feasibility of peritoneal ports for management of patients with cirrhotic refractory ascites, 10 ports were placed in nine patients for frequent outpatient paracentesis. Retrospective review and telephone interviews were used to assess port performance. Kaplan-Meier analysis revealed a median duration of port patency of 255 days. In 1,557 port days, four access problems prompted further interventional evaluation. Three cases of bacterial peritonitis and one catheter obstruction developed. The use of subcutaneous venous access ports to allow control of ascites by nursing personnel is a promising alternative for management of patients with refractory ascites. Additional studies are needed to determine long-term effectiveness and safety.

Evaluation of bone contusions with fat-saturated fast spin-echo proton-density magnetic resonance imaging

OBJECTIVE

To evaluate the efficacy of fast spin-echo proton-density magnetic resonance imaging (MRI) with fat saturation sequences in the evaluation of bone contusions at the knee.

METHODS

Analysis of 46 consecutive knee MRI examinations performed on patients referred from a sports medicine clinic after knee trauma. All examinations included coronal fast spin-echo proton-density fat saturation, fast spin-echo proton-density and fast spin-echo T2-weighted sequences. All 3 coronal sequences were blindly reviewed independently of each other by 3 experienced musculoskeletal radiologists to identify and grade bone contusions.

RESULTS

Thirty-five bone contusions were identified in 24 patients. All bone contusions were identified on fast spin-echo proton-density fat saturation sequences, which was significantly greater than the percentage identified on either fast spin-echo T2-weighted sequences (21/35, 60%, p < 0.001) or fast spin-echo proton-density sequences (10/35, 29%, p < 0.001). Fourteen (40%) of the contusions were identified only on the fast spin-echo proton-density fat saturation sequences. The average grade of contusion for all 35 examinations was also significantly higher on the fast spin-echo proton-density fat saturation sequences than on the fast spin-echo proton-density and fast spin-echo T2-weighted sequences (p < 0.05).

CONCLUSION

Fast spin-echo proton-density fat saturation sequences are more sensitive in the detection of bone contusions than fast spin-echo proton-density and fast spin-echo T2-weighted sequences. Assessment of other structures in the knee with fast spin-echo proton-density fat saturation MRI provides good spatial resolution and adequate T2-weighted information. It may have advantages over the more heavily T2-weighted fast spin-echo T2 fat saturation and inversion recovery sequences.

Congenital tarsal coalition: multimodality evaluation with emphasis on CT and MR imaging

Congenital tarsal coalition is a diagnosis that is often overlooked in young patients who first present with foot and ankle pain. Calcaneonavicular and talocalcaneal coalitions are encountered most frequently; fusion at other sites is much less common. Tarsal coalitions may be osseous, cartilaginous, or fibrous. Calcaneonavicular coalitions are readily detected on oblique radiographs. Radiographic confirmation of talocalcaneal coalition is more difficult than for fusion at other locations, although several secondary radiographic signs may indirectly suggest the diagnosis. Computed tomography (CT) and magnetic resonance (MR) imaging are invaluable for assessment of tarsal coalitions because they allow differentiation of osseous from nonosseous coalitions and because they depict the extent of joint involvement as well as secondary degenerative changes, features of vital importance in surgical planning. Short-inversion-time inversion recovery MR images may reveal bone marrow edema along the margins of the abnormal articulation, an important clue to the diagnosis. Moreover, CT or MR imaging may be required to confirm the diagnosis of talocalcaneal coalition when radiographic findings are equivocal. Because the diagnosis of tarsal coalition is often not entertained by the clinician ordering a CT or MR imaging examination, multiplanar imaging of the ankle and hindfoot is required.

Improvement of radiologists' characterization of mammographic masses by using computer-aided diagnosis: an ROC study

PURPOSE

To evaluate the effects of computer-aided diagnosis (CAD) on radiologists' classification of malignant and benign masses seen on mammograms.

MATERIALS AND METHODS

The authors previously developed an automated computer program for estimation of the relative malignancy rating of masses. In the present study, the authors conducted observer performance experiments with receiver operating characteristic (ROC) methodology to evaluate the effects of computer estimates on radiologists' confidence ratings. Six radiologists assessed biopsy-proved masses with and without CAD. Two experiments, one with a single view and the other with two views, were conducted. The classification accuracy was quantified by using the area under the ROC curve, Az.

RESULTS

For the reading of 238 images, the Az value for the computer classifier was 0.92. The radiologists' Az values ranged from 0.79 to 0.92 without CAD and improved to 0.87-0.96 with CAD. For the reading of a subset of 76 paired views, the radiologists' Az values ranged from 0.88 to 0.95 without CAD and improved to 0.93-0.97 with CAD. Improvements in the reading of the two sets of images were statistically significant (P = .022 and .007, respectively). An improved positive predictive value as a function of the false-negative fraction was predicted from the improved ROC curves.

CONCLUSION

CAD may be useful for assisting radiologists in classification of masses and thereby potentially help reduce unnecessary biopsies.

Complications in Paget disease at MR imaging

PURPOSE

To determine the MR imaging findings in patients with complications of Paget disease of bone.

MATERIALS AND METHODS

Of 45 patients with Paget disease who underwent MR imaging, 33 (26 men, seven women; age range, 64-91 years) with known complications of the disease were examined. Imaging in this subgroup included radiography (n = 26), computed tomography (n = 12), bone scintigraphy (n = 15), and magnetic resonance (MR) imaging (n = 33). Patients were examined specifically for musculoskeletal and neurologic complications of Paget disease, including fracture, basilar impression, spinal stenosis, bone tumor, and osteoarthrosis.

RESULTS

The 56 complications documented in the 33 patients were fracture (n = 17), neurologic entrapment (n = 19), neoplasm (n = 9), and arthropathy (n = 11). MR imaging was beneficial in the diagnostic evaluation of basilar impression (n = 7), spinal stenosis (n = 12), and the tumor stage (n = 9). It also helped to successfully evaluate pagetic bone narrowing of the coracoacromial arch, which was associated with impingement syndrome and rotator cuff rupture (n = 2). The signal intensities in pagetic bone were most commonly similar to those in fat; this finding had a 100% negative predictive value in excluding neoplasm.

CONCLUSION

Although Paget disease is diagnosed economically with conventional radiography, MR imaging is well suited for demonstrating the presence and extent of several characteristic disease complications, including basilar impression, spinal stenosis, and secondary neoplasm.

Identification of SV40 in brain, kidney and urine of healthy and SIV-infected rhesus monkeys

Recent reports of simian virus 40 (SV40) sequences in human tumors have prompted investigations into the poorly understood association of this polyomavirus with its primate host, the rhesus monkey (Macaca mulatta). In the present study we have used PCR to analyze tissues from 20 monkeys for the presence of SV40. Five of the animals, which were infected with simian immunodeficiency virus (SIV), were found to exhibit SV40-induced lesions and to have SV40 sequences present in their kidney and brain. Lesions associated with SV40 were not observed in 15 SIV monkeys, and SV40 DNA was detected in kidney and urine of only one of these animals. Three regions of SV40 DNA were examined in each tissue: the non-coding transcriptional control region (TCR), the sequences encoding the host range domain (HRD) within the carboxy-terminus of T antigen (TAg), and a portion of the VP1 gene. Each region contained nucleotide alterations compared to the SV40 reference strain 776. In all six animals, the TCR had an archetype structure containing a single 72 bp enhancer element. In addition, the TCR amplified from two animals lacked one of three copies of a GC-rich 21 bp repeat which is part of the promoter in strain 776. Multiple clones of unique HRD sequences were derived from different animals, and in some instances from the same animal. No correlation was found between a particular HRD sequence and its presence in a specific tissue type. Nucleotide changes identified within the VP1 gene indicate that this region, as with the closely-related human polyomavirus JCV, may permit the typing of the virus into individual strains. This study is the first to characterize SV40 sequences present in both healthy and SIV-infected animals and supports the suggestion that strain 776 is not the predominant type of SV40 circulating in its natural host.

Power Doppler sonography in tenosynovitis: significance of the peritendinous hypoechoic rim

The aim of this study was to evaluate the ability of power Doppler sonography to distinguish between hypoechoic fluid and synovium in patients with suspected tenosynovitis. Gray scale sonography and power Doppler sonography were performed on 26 tendons in 24 patients with tenosynovitis and 30 tendons in five asymptomatic volunteers. Peritendinous blood flow was graded on a scale of 0 to 3 and the percentage of the hypoechoic rim that contained blood flow was also noted. In the symptomatic group, flow was demonstrated in more than 50% of the peritendinous hypoechoic rim in 17 of 26 tendons. A positive correlation was found between the power Doppler sonographic grade and the percentage of the rim that had flow. These results suggest that a significant proportion of the hypoechoic rim probably represents vascularized synovium rather than complex fluid.

Extraskeletal mesenchymal chondrosarcoma of the rectus sheath

Mesenchymal chondrosarcomas (MSCs) are a rare form of chondrosarcoma which usually arise in bone. Extraskeletal chondrosarcomas constitute a minority (14-25%) of MSCs. We describe the imaging features of an extraskeletal mesenchymal chondrosarcoma that arose from the rectus abdominus muscle.

Power Doppler sonography: use in measuring alterations in muscle blood volume after exercise

OBJECTIVE

The purpose of this study was to show the ability of power Doppler sonography (PDS) to evaluate exercise-induced changes in muscle blood volume.

SUBJECTS AND METHODS

We evaluated 20 biceps muscles with PDS in 10 healthy volunteers before and after they underwent a standardized exercise protocol. Intramuscular blood volume was qualitatively analyzed using a subjective scoring system to evaluate vascular conspicuity, comparing sonograms obtained before and after exercise. We also collected preliminary data on the quantification of estimated fractional moving blood volume (EFMBV) measured on sonograms obtained in eight biceps muscles of five volunteers. Assessment of significance was calculated using a Wilcoxon signed-rank correlation of significance. The stability of relative changes in EFMBV was also assessed with measurements performed at three different times in five healthy volunteers.

RESULTS

With exercise, all 20 biceps muscles showed a significant subjective increase in apparent vascularity (p < .0005). Likewise, preliminary data on EFMBV showed significant increases (p < .01) between baseline and peak exercise values (mean, 470%; range, 180-900%).

CONCLUSION

PDS revealed marked increases in intramuscular vascular conspicuity after exercise. EFMBV provided a potentially useful parameter to document such increases quantitatively.

Power Doppler sonography in the assessment of musculoskeletal fluid collections

OBJECTIVE

Power Doppler sonography is a relatively new technique that has been shown to depict hyperemia associated with musculoskeletal inflammatory disease. We performed this study to evaluate the ability of power Doppler sonography to differentiate musculoskeletal fluid collections of varying etiologies.

SUBJECTS AND METHODS

Gray-scale and power Doppler sonography were performed on 39 patients with joint effusions or appendicular fluid collections. Blood flow (hyperemia) in the soft tissues adjacent to the fluid collections was subjectively analyzed and graded on a scale of 1 to 4 (1, normal flow; 2-4, increasing degrees of hyperemia). All fluid collections were aspirated within 24 hr of the sonographic examination. We found 31 joint effusions and 12 periarticular collections with appropriate imaging and pathologic correlation.

RESULTS

Adjacent to 36 effusions and fluid collections, we saw moderate or marked hyperemia. Thirty-five of the 36 had an inflammatory or neoplastic cause, including 15 infected collections. One fluid collection had a degenerative etiology (subdeltoid bursitis secondary to supraspinatus tendon tear). Adjacent to the seven remaining effusions and fluid collections, we saw normal or mildly increased hyperemia; none of these collections had an inflammatory etiology.

CONCLUSION

Power Doppler sonography helps distinguish inflammatory and infectious musculoskeletal fluid collections from those that are noninflammatory, and it may help guide the decision to perform diagnostic aspiration. Power Doppler sonography does not reliably differentiate between inflammatory collections of infectious and noninfectious origin because collections of either origin may significantly increase adjacent soft-tissue perfusion.

Power Doppler sonography of synovitis: assessment of therapeutic response--preliminary observations

Power Doppler sonography was used in eight symptomatic knees in seven patients with arthritis before and after joint aspiration and intraarticular administration of steroids. A qualitative decrease in synovial perfusion was observed in all eight knees, and symptoms improved in seven of the eight cases. These preliminary data suggest a role for power Doppler sonography in assessment of serial changes in synovial inflammation.

Prostate cancer: diagnosis with color Doppler sonography with histologic correlation of each biopsy site

PURPOSE

To correlate the findings at prostate color Doppler sonography (CDS) with those of site-specific transrectal core biopsy.

MATERIALS AND METHODS

Forty-three patients underwent prostate transrectal ultrasonography (US) and biopsy. CDS was performed at all biopsy sites before US-guided core biopsy. Vascularity at CDS was prospectively graded on a scale of 0-2 (0 = no visible peripheral zone [PZ] flow, 2 = markedly increased PZ vascularity). CDS results were correlated with histologic findings from 220 separate biopsy sites that included 27 focal lesions.

RESULTS

Of 34 grade 2 biopsy sites, 21 revealed carcinoma, eight revealed prostatitis, and five were negative. CDS depicted at least one focus of carcinoma in seven patients with no gray-scale abnormality. CDS had a sensitivity of 49%, specificity of 93%, and positive predictive value of 62%.

CONCLUSION

Focal PZ hypervascularity at CDS is associated with an increased likelihood of prostate cancer or inflammation at biopsy, often without a focal gray-scale abnormality. CDS may help identify an appropriate site for biopsy. A negative CDS scan, however, should not preclude biopsy, as CDS has a limited sensitivity in the detection of all sites of cancer.

The surgical management of intra-abdominal inflammatory conditions during pregnancy

The timely diagnosis and treatment of intra-abdominal conditions during pregnancy can challenge the surgical consultant. Familiarity with the anatomic and physiologic changes present in normal pregnancy is essential, as is the knowledge of relative risk by trimester. The general surgeon will be called upon to diagnose and treat appendicitis, biliary tract disease (including pancreatitis), and liver disease. Knowledge of how these conditions become manifest is essential. The surgical consultant should be aware that virtually all complications that occur in the management of these conditions are caused by delay in the detection of the disease process.

The location of abdominal wall blood vessels in relationship to abdominal landmarks apparent at laparoscopy

OBJECTIVE

Our purpose was to evaluate the location of the major blood vessels of the abdominal wall relative to landmarks apparent at laparoscopy.

STUDY DESIGN

Abdominal computed tomographic images of 21 reproductive-aged women at an academic center were retrospectively reviewed to determine the location of the inferior epigastric, superficial epigastric, and superficial circumflex iliac arteries and the lateral rectus muscle margins in relation to the symphysis pubis, the umbilicus, and the abdominal midline. These locations were correlated with each other and with body mass index using Pearson's correlation coefficient.

RESULTS

Above the symphysis the inferior and superficial epigastric arteries were 5.6 +/- 1.0 cm (mean +/- SD) and 5.5 +/- 2.0 cm from the midline, respectively. Although the location of these two vessels correlated (r = 0.6, p = 0.02), the mean difference in their location was 1.4 +/- 1.1 cm. Near the level of the umbilicus the superficial epigastric and circumflex iliac arteries and the lateral rectus muscle margin were 4.6 +/- 1.4 cm, 10.7 +/- 1.7 cm, and 7.6 +/- 1.5 from the midline, respectively. Only the lateral rectus muscle margin correlated with body mass index (r = 0.65, p = 0.004).

CONCLUSION

When laparoscopic landmarks are not visible to guide placement, lateral trocars should be placed approximately 8 cm from the midline and at least 5 cm above the symphysis to minimize the risk of vessel injury.

Detection of soft-tissue hyperemia: value of power Doppler sonography

OBJECTIVE

Power Doppler sonography is a new technique that offers extended dynamic range over that provided by conventional color Doppler imaging, thereby facilitating measurement of tissue perfusion. We evaluated the efficacy of power Doppler sonography in depicting soft-tissue hyperemia in musculoskeletal inflammatory conditions.

SUBJECTS AND METHODS

Twenty-three patients with predominantly unifocal musculoskeletal symptoms were evaluated with conventional gray-scale imaging and power Doppler sonography. The shoulder was evaluated in 14 patients, the elbow in three, and various other sites in six. For comparison purposes, the contralateral asymptomatic joint or site was examined in 17 cases. Fluid collections were aspirated in seven patients.

RESULTS

Soft-tissue hyperemia was seen on power Doppler sonograms at the symptomatic site(s) in 22 of 23 cases studied, with an appearance ranging from frank tissue blush to large, isolated peritendinous/peribursal vessels. Findings associated with hyperemia included rotator cuff tendinitis and/or tear, bursitis, and symptomatic wrist ganglia. Findings on power Doppler sonograms were normal in one patient who had a small, sterile hip joint effusion, and findings on subsequent scintigrams, pelvic radiographs, and CT scans were normal.

CONCLUSION

Power Doppler sonography consistently shows hyperperfusion associated with musculoskeletal inflammatory disease. As such, it represents a useful adjunct to gray-scale sonography in these settings, particularly as findings on conventional sonograms in inflammatory conditions can be nonspecific.

Palmaz stent in the treatment of central venous stenosis: safety and efficacy of redilation

PURPOSE

To assess the safety and efficacy of redilation of central venous stents in a growing animal model.

MATERIALS AND METHODS

Palmaz stents were placed in the inferior vena cava (IVC) in 18 newborn lambs. After 5 months, vena cavography was performed. Those animals in which growth of the IVC adjacent to the stent and/or neointimal hyperplasia had resulted in a stenosis were considered candidates for redilation. Repeat vena cavography, intravascular ultrasound, and histologic examination were performed at 2 or 6 months.

RESULTS

A stenosis of > 20% was demonstrated in 13 animals. Redilation was performed, and a 50% mean increase in stent diameter was achieved. There were no immediate complications. Late complications included nonocclusive laminar clot (n = 2), and a bar of tissue dividing but not occluding the caval lumen (n = 1). Moderate neointimal hyperplasia occurred in all stents. Stent compression (unrelated to redilation) occurred in seven animals.

CONCLUSION

Palmaz stents can be redilated safely and effectively in an animal model of growing central veins.

Imaging of lymphoma with PET with 2-[F-18]-fluoro-2-deoxy-D-glucose: correlation with CT

PURPOSE

To prospectively compare the accuracy of positron emission tomography (PET) with 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) in imaging thoracicoabdominal lymphoma to that of computed tomography (CT).

MATERIALS AND METHODS

Sixteen patients with lymphoma (11 with non-Hodgkin lymphoma [NHL] and five with Hodgkin disease) underwent FDG-PET and CT. Blinded, independent interpretations of PET and CT studies were followed by a direct comparison of the images. Measurement of tumor uptake of FDG was performed on positive PET studies.

RESULTS

Fifty-four foci of abnormal uptake were detected with PET in 13 patients. Forty-nine corresponding sites of lymphadenopathy and/or masses were detected with CT. All sites of adenopathy seen at CT were detected at PET. Three patients with Hodgkin disease had negative findings at abdominal PET, CT, and subsequent staging laparotomy. FDG uptake was comparable for both the low- and intermediate-grade lymphomas.

CONCLUSION

These preliminary data indicate excellent accuracy for FDG-PET imaging of thoracicoabdominal lymphoma. All grades of NHL were successfully imaged with FDG-PET. PET appears to be a useful method for imaging lymphoma.

False-negative morphine-augmented cholescintigraphy: a case of subacute gallbladder perforation

The gallbladder and an infected pericholecystic biloma secondary to subacute perforation were visualized during morphine-augmented cholescintigraphy. Perforation of the gallbladder may relieve cystic duct obstruction and contribute to false-negative visualization in the setting of acute cholecystitis.

Focal spared area in fatty liver simulating a mass. Scintigraphic evaluation

The characterization of focally spared areas in a fatty liver may at times be problematic. This report illustrates the unique diagnostic role that combined xenon-133/technetium-99m sulfur colloid scintigraphy can play in such cases.

Stability and structure of three-way DNA junctions containing unpaired nucleotides

Non-paired nucleotides stabilize the formation of three-way helical DNA junctions. Two or more unpaired nucleotides located in the junction region enable oligomers ten to fifteen nucleotides long to assemble, forming conformationally homogeneous junctions, as judged by native gel electrophoresis. The unpaired bases can be present on the same strand or on two different strands. Up to five extra bases on one strand have been tested and found to produce stable junctions. The formation of stable structures is favored by the presence of a divalent cation such as magnesium and by high monovalent salt concentration. The order-disorder transition of representative three-way junctions was monitored optically in the ultraviolet and analyzed to quantify thermodynamically the stabilization provided by unpaired bases in the junction region. We report the first measurements of the thermodynamics of adding an unpaired nucleotide to a nucleic acid three-way junction. We find that delta delta G degrees (37 degrees C) = +0.5 kcal/mol for increasing the number of unpaired adenosines from two to three. Three-way junctions having reporter arms 40 base-pairs long were also prepared. Each of the three reporter arms contained a unique restriction site 15 base-pairs from the junction. Asymmetric complexes produced by selectively cleaving each arm were analyzed on native gels. Cleavage of the double helical arm opposite the strand having the two extra adenosines resulted in a complex that migrated more slowly than complexes produced by cleavage at either of the other two arms. It is likely that the strand containing the unpaired adenosines is kinked at an acute angle, forming a Y-shaped, rather than a T-shaped junction.

Venesection as a rare form of self-mutilation

This case history records a rare form of self-mutilation, venesection. Underlying psychopathological mechanisms are presented, and contrasted with findings in the only other similar case reported in the English literature. The complex etiology of self-mutilating is reviewed with reference to this case report.

Factors affecting desired family size among preliterate New Guinea mothers

A random sample of 331 Enga mothers in Papua New Guinea perceived that an average of 5.96 live births (S.D. = 1.88) were needed to achieve their mean desired completed family size (DFS) of 4.65 children (S.D. = 1.32). The mean of the personal child mortality rates projected by the individual mothers. 194/1000, is very close to the rate of 198/1000 (224 deaths among 1134 live births) experienced by the women as a group and the 177/1000 documented in a 1972 prospective study in the area. This suggests that as a group preliterate women may possess an accurate estimate of prevailing child mortality rates. Considerable interest in family planning was shown. However for cultural or linguistic reasons, the majority (except in the case of the pill and tubal ligation) expressed no opinions about their readiness to use specific modern methods. The mean parity of 43 women seeking tubal ligation was 5.98 (S.D. = 1.81). An integrated maternal health and family planning program focusing on the health benefits to mother and child of the current 3-4-year birth interval seems indicated.

Inactivation of polioviruses and coxsackieviruses in surface water

Inactivation rates of polioviruses 1 and 3 and coxsackieviruses A-13 and B-1 were determined in situ in the Rio Grande in southern New Mexico, using membrane dialysis chambers. Inactivation of the viruses was exponential, and the rates of inactivation were apparently affected principally by the water temperature. Stability of the viruses in river water differed, with poliovirus 1 and coxsackie B-1 being most stable. Typically 1-log reductions of infectivity at water temperatures ranging between 23 and 27 degrees C required 25 h for poliovirus 1, 19 h for poliovirus 3, and 7 h for coxsackie virus A-13. At water temperatures of 4 to 8 degrees C, the log reduction times for poliovirus 1 and coxsackievirus B-1 were 46 and 58 h, respectively. Results obtained with labeled poliovirus 1 and coxsackievirus B-1 and with infectious ribonucleic acid indicate that inactivation was due to damage to viral ribonucleic acid. Virus-inactivation rates were also affected by heat sterilization of river water, indicating the presence of a heat-labile or volatile inactivating factor. The inactivating factor in Rio Grande water was apparently present at a constant concentration over a 1-year period.

Interactions between health and population

Both health and population have multiple direct and indirect, as well as positive and negative, influences on each other and on the development process. There is much evidence to show that high fertility produces multiple health hazards and that family planning is one of the most effective health measures available. Conversely, there are also multiple ways in which health influences fertility. Whereas health services resulting in reduced morbidity and mortality have often been considered a major cause of population growth, the authors argue that health programs can also contribute to a more rapid decline in birth rates by facilitating the increased practice of family planning. Evidence is reviewed to support the position that family planning services can be more effective, efficient, and acceptable when combined with maternal and child health and nutrition programs.

Gas chromatographic presumptive test for coliform bacteria in water

A gas chromatographic procedure which shows promise as a presumptive test for coliform bacteria in water is described. Total coliform bacteria concentrations were determined from the incubation times at 37 C required for ethanol to be produced. Fecal coliform densities were determined in a similar manner at 44.5 C. The culture medium was filter sterilized M-9 salts supplemented with 1% lactose, 0.1% Casamino Acids, and 0.1% yeast extract. Best results were obtained when the initial total coliform concentrations were 5 per ml or higher and when fecal coliform concentrations were 50 per ml or higher. Minimum detection times at these concentrations were 9 and 12 h, respectively.