Underassessment of lower extremity deep venous thrombosis using color flow Doppler compared to compression sonography

The aim of this paper is to compare the accuracy of color Doppler to compression sonography in the diagnosis of lower extremity deep vein thrombosis. Longitudinal color flow imaging was performed in 60 lower extremities in patients with clinically suspected deep venous thrombosis (DVT). The study was then repeated by a blinded examiner using transverse compression sonography. The results were then correlated. Thirty-five examinations were negative by both color flow and compression methods. Twenty thrombi were diagnosed on compression sonography, while only 13 were diagnosed by the color flow method. Thirty-five percent of thrombi were missed using color flow imaging alone. We conclude that compression sonography should remain an integral part of the assessment of lower extremity DVT, as a significant number of thrombi might be overlooked using longitudinal color flow imaging alone. This is especially true in non-occlusive thrombi that are adherent to the vessel wall.

Wisconsin healthcare ethics committees

Over the past two decades ethics committees have proliferated in healthcare institutions across the country. Catalysts for this growth include the endorsement of ethics committees by the New Jersey Supreme Court in the Quinlan case, by the President's Commission for the Study of Ethical Problems in Medicine and Biomedical Research (“President's Commission”) in its report entitled Deciding to Forgo Life Sustaining Medical Treatment, by the U.S. Department of Health and Human Services in its 1985 “Baby Doe” regulations, by numerous other courts in treatment decisionmaking opinions issued after Quinlan, and more recently by the Joint Commission on Accreditation of Healthcare Organizations (JCAHO).

MRI of the liver. A pictorial essay

Magnetic resonance imaging (MRI) is an extremely useful modality for evaluation of the complex pathophysiology of the liver. The high degree of soft tissue contrast afforded by MRI accurately detects and characterizes both focal and diffuse abnormalities of the liver. In this article we present a pictorial review of MRI of the liver.

Successful correction of hemophagocytic lymphohistiocytosis with related or unrelated bone marrow transplantation

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disorder of immune regulation leading to widespread lymphocytic and hemophagocytic infiltration of vital organs. Apparent cure has only been achieved with allogeneic bone marrow transplantation (BMT). This report describes 20 consecutive patients, who underwent either matched sibling donor (n = 4) or unrelated donor (URD; n = 16) BMT. Age at the time of BMT was 0.4 to 5.3 years (median, 0.8 years). Central nervous system disease was present at diagnosis in 13 patients. At BMT, 14 patients were in a clinical remission, whereas 6 patients had active HLH. All patients were engrafted after cytoreduction with busulfan, cyclophosphamide, and etoposide. The probability of grade II-III acute graft-versus-host disease (GVHD) for all patients was 57% (95% confidence limit [CL], 0.28, 0.86), and 73% (95% CL, 0.44, 1.0) in URD patients. The overall probability of survival at 3 years was 45% (95% CL, 0.23, 0.67) and 44% (95% CL, 0.19, 0.68) when URD BMT was evaluated separately. Favorable BMT outcome was associated with clinical remission status at the time of BMT. The preparative regimen was well tolerated, and in the 9 surviving patients it provided durable engraftment and was effective at eradicating the underlying disease.

CT diagnosis of acquired intercostal lung herniation

Intercostal lung herniation is a rare complication of trauma, best demonstrated by computed tomography. Most intercostal lung herniations are the result of direct trauma to the chest wall or occur at sites of prior percutaneously placed chest tubes. We present two cases of acquired intercostal lung herniation.

Ablative adenoidectomy: a new technique using simultaneous liquefaction/aspiration

OBJECTIVE

This study was performed to critically evaluate a new cautery technique for adenoidectomy that combines indirect visualization with complete hemostasis, ultimately permitting the surgeon to tailor the procedure to the patient's specific needs.

DESIGN

This prospective study of 138 consecutive adenoidectomy patients of the senior author was carried out at the Montreal Children's Hospital over 17 months. Concurrent adenoidectomy patients of another senior otolaryngologist in our institution as well as cases of the senior author using the conventional cold curettage technique served as controls.

METHOD

Data were collected preoperatively with respect to indication for surgery and radiologic findings. Operative findings including duration of surgery, concurrent procedures, position of adenoid hypertrophy, and blood loss were also recorded. Postoperative complications such as hemorrhage, infection, dehydration, as well as the incidence of velopharyngeal insufficiency and nasopharyngeal stenosis were also recorded up to 1 year from the date of surgery. The operative technique involves indirect visualization of the nasopharynx with a laryngeal mirror combined with cautery-liquefaction and suction ablation of the adenoid tissue.

RESULTS

Our results demonstrate a significant reduction in blood loss as well as a reduction in operative time. There was a low incidence of postoperative infection, no patients required a return to the operating room for hemostasis, and there were no cases of recurrent adenoid hypertrophy. There was no detectable difference in the incidence of postoperative complications.

CONCLUSION

We conclude that this technique is safe and time-efficient, with the advantages of excellent visualization and essentially no operative blood loss.

Influence of prone position on the extent and distribution of lung injury in a high tidal volume oleic acid model of acute respiratory distress syndrome

OBJECTIVE

To evaluate the influence of body position on the extent and distribution of experimental lung damage in an oleic acid canine model of acute respiratory distress syndrome, using mechanical ventilation with high tidal volumes and positive end-expiratory pressure (PEEP).

DESIGN

Prospective, randomized study.

SETTING

Experimental animal laboratory.

SUBJECTS

Twelve anesthetized and paralyzed dogs.

INTERVENTIONS

Ninety minutes after lung injury was induced by injection of oleic acid, 12 animals were randomized to be ventilated for 4 hrs, in either the supine (supine group, n = 6) or prone (prone group, n = 6) positions, using the same ventilatory pattern (F10(2) 0.6, PEEP > or = 10 cm H2O, and a tidal volume that generated a peak transpulmonary pressure of 35 cm H2O when implemented in the supine position). Regardless of randomization to position, the tidal volumes, F10(2), and PEEP were kept constant and the pulmonary artery occlusion pressure was maintained between 4 and 6 mm Hg for the duration of the study.

MEASUREMENTS AND MAIN RESULTS

At the end of the protocol, the lungs were excised for gravimetric determination (wet/dry weight ratio) and histologic examination (histologic score). Changes over time in the static pressure-volume curve of the lungs (obtained in the supine position) were also used as end-point variables. At baseline, hemodynamic and respiratory variables did not differ between groups. Just before randomization to position (90 mins after oleic acid injection), both groups presented similar lung static pressure-volume curves. Pulmonary artery occlusion pressure (4.3 +/- 1.9 vs. 4.8 +/- 1.3 mm Hg [supine vs. prone group]), cardiac output (4.1 +/- 0.4 vs. 5.2 +/- 1.3 L/min [supine vs. prone group]), and venous admixture (36.7 +/- 20.7% vs. 28.3 +/- 19.4% [supine vs. prone group]) were also not significantly (p > .05) different when measured in the supine position. At the end of the experiment, lung gravimetric data in the two experimental groups were not statistically different, suggesting a similar extent of edema. Histologic abnormalities, however, were less in the prone group than in the supine group (p < .01), due primarily to marked differences in extent and severity in the dependent regions of the lungs. Static lung compliance improved over time in the prone group (34 +/- 9 to 46 +/- 19 mL/cm H2O)(p = .02), but not in the supine group (34 +/- 6 to 36 +/- 6 mL/cm H2O).

CONCLUSIONS

After oleic acid-induced lung injury, animals ventilated with high tidal volume and PEEP undergo less extensive histologic change in the prone position than in the supine position. The prone position alters the distribution of histologic abnormalities.

CT appearance of the Syed-Neblett device for interstitial brachytherapy of gynecologic malignancies

Radiation therapy is an important adjuvant treatment for gynecological malignancies. However, the maximum amount of radiation treatment is limited by the side effects to the normal local tissue. We present a brief summary of the use and appearance of the Syed-Neblett intracavitary device. This device allows delivery of radioactive implants to a local tumor resulting in maximum dosage to tumor tissue, but limiting dosage to the surrounding normal tissue.

Renovascular hypertension

In current clinical practice, angiographic evaluation of patients with suspected renovascular hypertension usually follows clinical suspicion and positive captopril scintigraphy. Early digital angiography and percutaneous renal artery angioplasty have evolved as the accepted treatment pattern. Doppler sonography and MR angiography continue to be evaluated as potential methods of noninvasive screening.

Detection of hepatocellular carcinoma in cirrhotic patients: sensitivity of CT and ultrasonography

Patients with cirrhosis are at increased risk for the development of hepatocellular carcinoma. The heterogeneous hepatic parenchyma produced by cirrhosis makes detection of hepatomas more difficult. The purpose of this study was to determine the sensitivities of CT and ultrasonography for detecting hepatomas in cirrhotic patients. A retrospective analysis was performed of 733 patients who underwent liver transplantation at our institution. A study population of 21 patients was selected who met our inclusion criteria. The inclusion criteria required a pathologic diagnosis of hepatocellular carcinoma, pathologic evidence of cirrhosis, and contrast-enhanced CT and sonographic examinations performed within 1 week of each other. The sensitivities of CT and ultrasonography were determined by comparing the imaging findings with pathology findings from serially sectioned total hepatectomy specimens. A total of 40 hepatomas were detected pathologically in the 21 patients in our study population. CT identified 12 of 21 patients with hepatomas and detected 18 of 40 individual lesions (patient detection sensitivity = 57%, lesion detection sensitivity = 45%). Ultrasonography identified 14 of 21 patients with hepatomas and detected 21 of 40 individual lesions (patient detection sensitivity = 67%, lesion detection sensitivity = 51%). Combining the findings of CT and ultrasonography allowed identification of 17 of 21 patients with hepatomas and detection of 24 of 40 individual lesions (patient detection sensitivity = 80%, lesion detection sensitivity = 60%). We conclude that CT and ultrasonography have a low sensitivity for the detection of hepatocellular carcinoma in patients with cirrhosis.

Tracheal gas insufflation: catheter effectiveness determined by expiratory flush volume

Used adjunctively during mechanical ventilation, tracheal gas insufflation (TGI) improves CO2 elimination, principally by decreasing effective anatomic dead space. Continuing lung deflation at end- expiration raises the end-expiratory C02 concentration within the proximal airway, and could theoretically reduce the efficiency of a given catheter flow. To test this possibility, we designed a series of experiments that examined the influence of TGI delivery patterns on the efficiency of CO2 elimination. Using a gating device, catheter flow was delivered selectively during desired portions of expiration. Paralyzed, ventilated dogs were studied at short and extended inspiratory time fractions (TI/TT) with inspiratory tidal volume and ventilator frequency held constant. The expiratory flush volume, not the pattern of gas delivery, determined the observed decline in PaCO2, provided that the end-expiratory period was included in the catheter flush period. Despite continuing end-expiratory lung deflation (extended TI/TT), catheter effectiveness remained the same at matched expiratory flush volumes. To determine if enhanced distal mixing at the higher catheter flows required during the extended TI/TT (to match expiratory flush volume) masked a decrease in efficiency, we repeated the experiment with a tip-inverted catheter. We again found that matched catheter delivered expiratory volumes were similarly effective. With or without ongoing lung deflation, the volume of gas flushed during the expiratory period determined the effectiveness of TGI, provided that inspired minute ventilation remains unchanged and end-expiration is included in the catheter flush period.

Malignant neoplasms following bone marrow transplantation

We undertook an analysis of 2,150 recipients of bone marrow transplant (BMT) at the University of Minnesota to determine the incidence of post-BMT malignant neoplasms (MNs). Fifty-one patients developed 53 MNs, compared with 4.3 expected from general population rates (standardized incidence ratio [SIR], 11.6, 95% confidence interval [CI], 8.2-14.5). These included 22 occurrences of B-cell lymphoproliferative disorder (BLPD), 17 solid nonhematopoietic tumors, 10 myelodysplastic syndromes (MDS), 1 acute myelogenous leukemia (AML), 2 non-Hodgkin's lymphoma (NHL), and 1 Hodgkin's disease (HD). The estimated actuarial incidence of any post-BMT malignancy was 9.9% +/- 2.3% at 13 years posttransplant. The cumulative probability of BLPD plateaued at 1.6% +/- 0.3% by 4 years from transplant and factors independently associated with increased risk included in vitro T-cell depletion of marrow (relative risk (RR) = 11.9, P < .001), HLA mismatch (RR = 8.9, P < .001), use of antithymocyte globulin (ATG) for graft versus host disease (GVHD) prophylaxis (RR = 5.9, P < .001) or in the preparative regimen (RR = 3.1, P = .03) and primary immunodeficiency (RR = 2.5, P = .06). The cumulative probability of developing solid malignancy was 5.6% +/- 2.2% at 13 years from BMT. Malignant melanomas were the most common (SIR, 10.3, 95% CI 1.9 to 25.4). The actuarial incidence of MDS/AML plateaued at 2.1% +/- 0.8% at 9 years and was seen most often in older patients receiving autologous peripheral blood stem cells for HD or NHL. These data document that BMT recipients are at an increased risk of later malignancy, which may add significant morbidity and mortality to the transplant process. Methods for screening and identification of individuals at increased risk need to be addressed in future studies.

Systemic venous enhancement patterns during dynamic abdominal CT

In 25 patients we assessed the enhancement of abdominal venous structures during dynamic computed tomography (CT). The degree of venous enhancement demonstrated great variation. In six instances (out of 250 observations) a vessel was visually perceived as not enhancing and potentially thrombosed, including three gonadal veins. CT measurements were helpful in identifying enhancement, but were occasionally low enough that thrombosis remained a radiological consideration. The great variation in venous enhancement makes the diagnosis of thrombosis suspect, based on CT alone. Corroboration of this finding is suggested, when clinically relevant.

Treatment of head and neck hemangiomas with recombinant interferon alpha 2B

Fifteen patients with head and neck hemangiomas were treated with systemic recombinant interferon alpha 2b (rIFNalpha2b, Schering). There were 14 infants and 1 adult in the group, ranging in age from 5 weeks to 24 years old. Of the 15 patients in the group, 5 had involvement of the airway. Three of the patients had previously failed alternative systemic therapy. Twelve patients have had a beneficial response. Ten patients have completed the therapy and have been off interferon from 6 to 53 months without reappearance or progression of the disease. Two patients are currently on the therapy with resolving lesions. Three patients had minimal response and underwent successful surgical resection. No major toxicity was encountered during the therapy. Our experience demonstrates that rIFNalpha2b is a well-tolerated and effective therapy for hemangiomas of the head and neck that require intervention.

Health care providers' liability exposure for inappropriate pain management

Recent studies have exposed the startling inadequacy of health care providers knowledge about and practice of effective pain management. For example, in one study, it was reported that 79 percent of a random sample of 454 medical-surgical inpatients experienced pain during hospitalization, and that 58 percent of patients with pain considered the pain horrible or excruciating. In another study, 67 percent of 2,415 randomly selected hospitalized patients had pain during the twenty-four hours prior to being interviewed, and 50 percent reported pain at the time of the interview. In a study of seriously ill hospitalized patients reported in 1996, half of the patients complained of pain, and one-sixth reported that they experienced extremely severe pain at least half the time. According to one literature review, 75 percent of cancer patients have reported suffering pain, and one study estimates that 25 percent of cancer patients die with severe unrelieved pain. Chronic nonmalignant pain has been described as an extremely prevalent problem, and over two-thirds of nursing home residents experience serious pain.

A 24 year follow up of an isolated lymphangioma of the kidney

Renal lymphangioma is a rare benign tumor of the kidney. An example is presented which was initially identified by excretory urography, angiography and biopsy. A 24 year follow up included computed tomography. The radiographic findings, pathogenesis and natural history of this unusual tumor are discussed.

Abdominal aortic coarctation: CT, MRI, and angiographic correlation

Abdominal aortic coarctation is an uncommon entity in the elderly. We present a case of abdominal aortic coarctation with computed tomography (CT), magnetic resonance imaging (MRI) and conventional angiographic correlation. CT and MR imaging detected an abnormal abdominal aorta distal to the origin of the celiac axis with the diagnosis of abdominal aortic coarctation confirmed by conventional angiography. Clinical presentation and diagnostic imaging findings depend on the level of the coarctation and its relationship to the renal vessels.

Mismatched bone marrow transplantation for Omenn syndrome: a variant of severe combined immunodeficiency

Omenn syndrome is a variant of SCID, inherited as an autosomal recessive disorder, and characterized by severe eczematoid dermatitis, eosinophilia, elevated serum IgE and a distinctive histology in enlarged lymph nodes. The etiology of Omenn syndrome is unknown, however, unlike other forms of SCID; patients with Omenn syndrome have activated T lymphocytes in their circulation capable of non-MHC restricted cytotoxic function. Recently, it has been observed that the use of immunosuppressive therapy, particularly cyclosporine, can modify the clinical manifestations of the disorder. Prior to the use of bone marrow transplantation this disease was universally fatal. Death typically occurred in infancy as the result of opportunistic infections and/or malignancies, most notably lymphomas. While bone marrow transplantation has become quite successful for many phenotypes of SCID, even with the use of alternative donors other than histocompatible siblings, in Omenn syndrome it remains a challenge. In our experience, patients with Omenn syndrome exhibit a higher incidence of Gram negative sepsis, before and during transplantation, and carry a significant risk of post-transplant rejection when compared with patients with other phenotypes of SCID. We report the results of six patients treated with bone marrow transplantation from alternative donors, three had unrelated donors (URD) and three had haplo-identical parental donors. Five of the six patients achieved complete and/or durable donor cell engraftment and only one patient experienced acute GVHD. Three patients died of transplant-related complications (infection or EBV-associated B cell lymphoma) between day +22 and day +95 post-transplant. Three patients survived more than 1 year post-transplant.(ABSTRACT TRUNCATED AT 250 WORDS)

Case report: MRI of extrapancreatic gastrinoma

Islet cell tumors are a relatively rare group of neuroendocrine tumors that are often difficult to image preoperatively. We present the magnetic resonance imaging characteristics of an uncommon and unusually large extrapancreatic gastrinoma.

Efficacy of expiratory tracheal gas insufflation in a canine model of lung injury

Tracheal gas insufflation (TGI) improves the efficiency of CO2 elimination by reducing the CO2-laden dead space of the airways. The effect of TGI on PaCO2 diminishes in the setting of acute lung injury (ALI) because an increased alveolar component dominates the total physiologic dead space. Nevertheless, adopting a strategy of permissive hypercapnia should partially offset the decreased efficacy of TGI by increasing CO2 concentration in the proximal airways. To examine these issues we studied the CO2 removal efficacy of expiratory TGI as an adjunct to conventional mechanical ventilation (CMV) before and after oleic acid-induced lung injury (OAI). We first examined the effect of TGI before and after OAI, keeping tidal volume (VT) and frequency constant, and allowing PaCO2 to increase after OAI. We then tested TGI efficiency after matching PaCO2 after OAI to its pre-OAI level by increasing VT (post-OA/VT stage). PaCO2 was 53 +/- 3, 79 +/- 21, and 52 +/- 4 mm Hg in the pre-OAI, post-OAI, and post-OA/VT stages of CMV, respectively. The corresponding decrements in PaCO2 produced by TGI at a flow rate of 10 L/min were 16 +/- 3, 24 +/- 10, and 10 +/- 2 mm Hg, respectively. TGI decreased total physiologic dead space per breath (VD) by 56, 31, and 28 ml during the pre-OAI, post-OAI, and post-OA/VT stages, respectively. Despite a smaller reduction in VD during the post-OAI stage, the effect of TGI on PaCO2 was preserved because of the relatively high PaCO2 prior to its initiation.(ABSTRACT TRUNCATED AT 250 WORDS)

Transjugular intrahepatic portosystemic shunt: correlation of portal vein velocity measurements and portosystemic pressure gradients

To assess the relationship between portal vein velocity measurements and portosystemic gradients, color Doppler sonography was performed on 12 patients before and after transjugular intrahepatic portosystemic shunt placement. An additional patient was examined before and after shunt modification. The average maximum portal vein velocity increased from 15.7 cm s-1 before shunt placement to 43.5 cm s-1 after shunt placement, while the average portosystemic gradient decreased from 22.0 mm Hg before shunt placement to 7.9 mm Hg after shunt placement. Flow was observed within the shunt in 11 of the 12 cases. Shunt velocity was measurable in nine patients, with an average value of 115.7 cm s-1. Reversal of intrahepatic portal vein flow was observed in 10 cases following shunt placement. Color Doppler sonography is a useful non-invasive tool in the evaluation of intrahepatic portosystemic shunts, and changes in portal vein velocity correlate well with changes in the portosystemic gradient.

Abscess formation as a late complication of dropped gallstones

We describe a case of abscess formation 1.5 years postoperatively in a patient with dropped gallstones from laparoscopic cholecystectomy. The entity was initially recognized on computed tomography (CT) and the diagnosis was confirmed with ultrasound. Although this is a rare complication of laparoscopic cholecystectomy, it should be recognized as a potential source of abscess formation even in a patient presenting months after the procedure.

Orbital varix presenting as a subconjunctival mass

A 39-year-old woman presented with a vermiform superior conjunctival mass that progressively enlarged during 4 years of follow-up. Although magnetic resonance imaging suggested that the lesion was located in the superior forniceal conjunctiva, surgical exploration disclosed a vascular anomaly (varix) that extended deep into the orbit. The clinical features and management of orbital varices are discussed.