Frederick L. Hoff

Asymptomatic Peripheral Arterial Disease Is Associated With More Adverse Lower Extremity Characteristics Than Intermittent Claudication

Background— This study assessed functional performance, calf muscle characteristics, peripheral nerve function, and quality of life in asymptomatic persons with peripheral arterial disease (PAD). Methods and Results— PAD participants (n=465) had an ankle brachial index <0.90. Non-PAD participants (n=292) had an ankle brachial index of 0.90 to 1.30. PAD participants were categorized into leg symptom groups including intermittent claudication (n=215) and always asymptomatic (participants who never experienced exertional leg pain, even during the 6-minute walk; n=72). Calf muscle was measured with computed tomography. Analyses were adjusted for age, sex, race, ankle brachial index, comorbidities, and other confounders. Compared with participants with intermittent claudication, always asymptomatic PAD participants had smaller calf muscle area (4935 versus 5592 mm2; P<0.001), higher calf muscle percent fat (16.10% versus 9.45%; P<0.001), poorer 6-minute walk performance (966 versus 1129 ft; P=0.0002), slower usual-paced walking speed (P=0.0019), slower fast-paced walking speed (P<0.001), and a poorer Short-Form 36 Physical Functioning score (P=0.016). Compared with an age-matched, sedentary, non-PAD cohort, always asymptomatic PAD participants had smaller calf muscle area (5061 versus 5895 mm2; P=0.009), poorer 6-minute walk performance (1126 versus 1452 ft; P<0.001), and poorer Walking Impairment Questionnaire speed scores (40.87 versus 57.78; P=0.001). Conclusions— Persons with PAD who never experience exertional leg symptoms have poorer functional performance, poorer quality of life, and more adverse calf muscle characteristics compared with persons with intermittent claudication and a sedentary, asymptomatic, age-matched group of non-PAD persons.

Lower Extremity Ischemia, Calf Skeletal Muscle Characteristics, and Functional Impairment in Peripheral Arterial Disease

OBJECTIVES: To determine whether lower ankle brachial index (ABI) levels are associated with lower calf skeletal muscle area and higher calf muscle percentage fat in persons with and without lower extremity peripheral arterial disease (PAD).

Pathophysiological Changes in Calf Muscle Predict Mobility Loss at 2-Year Follow-Up in Men and Women With Peripheral Arterial Disease

Background— Associations of pathophysiological calf muscle characteristics with functional decline in people with lower extremity peripheral arterial disease are unknown. Methods and Results— Three hundred seventy participants with peripheral arterial disease underwent baseline measurement of calf muscle area, density, and percent fat with the use of computed tomography. Participants were followed up annually for 2 years. The outcome of mobility loss was defined as becoming unable to walk 1/4 mile or walk up and down 1 flight of stairs without assistance among those without baseline mobility limitations. Additional outcomes were ≥20% decline in 6-minute walk distance and becoming unable to walk for 6 minutes continuously among participants who walked continuously for 6 minutes at baseline. With adjustment for age, sex, race, body mass index, the ankle-brachial index, smoking, physical activity, relevant medications, and comorbidities, lower calf muscle density (P for trend <0.001) and lower calf muscle area (P for trend=0.039) were each associated with increased mobility loss rates. Compared with participants in the highest baseline tertiles, participants in the lowest tertile of calf muscle percent fat had a hazard ratio of 0.18 for incident mobility loss (95% confidence interval, 0.06 to 0.55; P=0.003), and participants in the lowest tertile of muscle density had a 3.50 hazard ratio for incident mobility loss (95% confidence interval, 1.28 to 9.57; P=0.015). No significant associations of calf muscle characteristics with 6-minute walk outcomes were observed. Conclusions— Our findings suggest that interventions to prevent mobility loss in peripheral arterial disease should focus on reversing pathophysiological findings in calf muscle.

Semiautomatic evaluation of left ventricular diastolic function with cine magnetic resonance imaging

RATIONALE AND OBJECTIVES Cine magnetic resonance (MR) imaging is a relatively new technique that can be used to study cardiac function with high spatial and temporal resolution. However, detailed functional analysis of the entire cardiac cycle with cine MR imaging is time consuming and labor intensive. We analyzed diastolic function using a semiautomatic routine that reduces the time necessary for analysis. METHODS Twenty subjects (10 normal control subjects and 10 patients with isolated diastolic dysfunction) were examined. Short-axis cine MR images were obtained at 32 phases of the cardiac cycle. A semiautomatic boundary-finding routine was used to determine left ventricular (LV) volumes at each phase. Volume-versus-time and first-derivative curves were created from these data. Several parameters derived from the MR imaging curves were used to characterize diastole. RESULTS Two parameters--the ratio of early peak filling rate to late peak filling rate and the percentage of filling during early diastole--perfectly distinguished subjects with LV diastolic dysfunction from the normal control subjects. The semiautomatic analysis method substantially reduced the time necessary for analyzing the MR imaging data, compared with manual analysis. CONCLUSION Cine MR imaging, especially with time-saving techniques such as our service automatic analysis method, has promise as a research and clinical tool in evaluating LV diastolic function.

MR imaging in hydatid disease of the liver

We describe the appearance on MR of hydatid disease of the liver in 2 patients. The lesions were well demonstrated using spin-echo pulse sequences, and could be easily seen with either T1 or T2 weighting; however, maximum information was obtained using both. In these 2 cases, a thin, low signal boundary was noted around the cysts; this finding may prove useful in differential diagnosis.

CT Diagnosis of Chyluria After Partial Nephrectomy

OBJECTIVE The purpose of this study was to describe the CT diagnosis of chyluria after partial nephrectomy. CONCLUSION Fat in the bladder can be identified on CT after partial nephrectomy. This finding is caused by chyluria secondary to lymphatic injury and should not be mistaken for other abnormalities. Our study population did not need treatment of chyluria.

OCCULT RETAINED PENILE PROSTHETIC FRAGMENTS IN PERSISTENT UROGENITAL INFECTIONS

Case 1. A 46-year-old black man with a history of T2a pros- tate cancer treated with radical retropubic prostatectomy un- derwent insertion of a penile prosthesis. This prosthesis was removed because of mechanical failure. The patient underwent 2 additional inflatable prosthesis implantations during the next 16 years, both of which explanted secondary to infection. Three months after the most recent explantation he noticed penile swelling and a rash over the scrotum. Evaluation elsewhere included contrast enhanced computerized tomography (CT) of the abdomen/pelvis as well as a skin biopsy. Diagnosis was Schonlein-Henoch purpura associated with a soft tissue phleg- mon of the anterior pelvis. There was no foreign body noted. The patient was referred to us 4 months later with the persistent complaints of intermittent discomfort and swell- ing of the entire penis, scrotum and suprapubic region. Non- enhanced CT of the pelvis using small cuts revealed a small foreign body near the peripheral aspect of the phlegmon in the scrotum (fig. 1). This finding was consistent with a re- tained segment of connecting tubing from a previously re- moved penile prosthesis. Surgical extirpation of the retained connecting tubing and phlegmon resulted in resolution of symptoms. Intraoperative ultrasound confirmed the absence of further retained foreign bodies. Intraoperative cultures yielded only rare Peptostreptococcus, while the gram stains revealed numerous white blood cells and gram positive cocci. Notably, the patient had been on broad-spectrum antibiotics preoperatively. Case 2. A 36-year-old black man with a history of recalci- trant erectile dysfunction underwent insertion of an inflat- able penile prosthesis. Mechanical failure required at- tempted revision and replacement of the prosthesis 1 year later. The new prosthesis became infected 11 months later and was removed. Four years later he underwent difficult reconstruction at a second medical center, which involved placement of a single cylinder into the right proximal crus crossing the midline into the left distal corporeal shaft. Op- erative notes indicated significant fibrotic changes.

Computed Tomography and Magnetic Resonance Imaging Features of Lesions of the Renal Medulla and Sinus

The kidneys can harbor a wide variety of lesions, many of which can be visualized by computed tomography and magnetic resonance imaging. In this article, the pertinent renal anatomic relationships as well as the histologic composition and function of the renal medulla and sinus are reviewed. Additionally, computed tomography and magnetic resonance imaging features of renal sinus and medullary lesions in adult patients are presented. This article reviews the salient imaging features of various malignant, benign neoplastic, and nonneoplastic lesions of the sinus and medulla.

Magnetic resonance imaging of pancreatic metastases from renal cell carcinoma

Pancreatic metastases are rare but are thought to be most commonly from renal cell carcinoma (RCC). These metastases can present many years after the initial tumor is resected, and accordingly, these patients require prolonged imaging follow-up. Although the computed tomographic findings of these metastases have been extensively reviewed in the literature, little has been written about the magnetic resonance imaging appearance of these metastases. Pancreatic metastases from RCC are typically T1 hypointense and T2 hyperintense. After intravenous administration of gadolinium, they are typically hypervascular and less commonly hypovascular. Chemical shift and diffusion-weighted imaging can aid in the diagnosis of these metastases.

Beyond hepatic hemangiomas: the diverse appearances of gastrointestinal and genitourinary hemangiomas

Hemangiomas are common lesions, best known for their appearance in the liver. Their appearance in less common locations, such as the gastrointestinal and genitourinary tracts, is less well known. We will review the typical and atypical appearance of hemangiomas in these locations on sonography, CT, and MRI.