Jonathan R. Medverd

The relationship between knee joint loading rate during walking and degenerative changes on magnetic resonance imaging

BACKGROUND While animal study and cadaveric study have demonstrated an association between knee joint loading rate and joint degeneration, the relationship between knee joint loading rate during walking and osteoarthritis has not yet been sufficiently studied in humans. METHODS Twenty-eight participants (14 transfemoral amputees and 14 age and body mass matched controls) underwent knee MRI with subsequent assessment using the semiquantitative Whole-Organ Magnetic Resonance Image Score. Each subject also underwent gait analysis in order to determine knee adduction moment loading rate, peak, and impulse and an exploratory measure, knee adduction moment rate∗magnitude. FINDINGS Significant correlations were found between medial tibiofemoral joint degeneration and knee adduction moment peak (slope=0.42 [SE 0.20]; P=.037), loading rate (slope=12.3 [SE 3.2]; P=.0004), and rate∗magnitude (slope=437 [SE 100]; P<.0001). These relationships continued to be significant after adjusting for body mass or subject type. The relationship between medial knee semiquantitative MRI score and knee adduction moment loading rate and rate∗magnitude continued to be significant even after adjusting for peak moment (P<.0001), however, the relationship between medial knee semiquantitative MRI score and peak moment was no longer significant after adjusting for either loading rate or rate∗magnitude (P>.2 in both cases). INTERPRETATION This study suggests an independent relationship between knee adduction moment loading rate and medial tibiofemoral joint degeneration. Our results support the hypothesis that rate of loading, represented by the knee adduction moment loading rate, is strongly associated with medial tibiofemoral joint degeneration independent of knee adduction moment peak and impulse.

How Radiologists Get Paid: Resource-Based Relative Value Scale and the Revenue Cycle

OBJECTIVE To learn the impact of health care reform, it is important for radiologists to first understand basic administrative aspects of medicine. This article describes the processes of radiology billing, reimbursement, and the revenue cycle, which includes the importance of proper coding, the resource-based relative value scale, and accounts receivable. CONCLUSION An understanding of the basics of medical practice management can help radiologists effectively provide optimal patient care. This article provides an overview of one component of this topic--the current radiology reimbursement system.

ACR White Paper: New Practice Models—Hospital Employment of Radiologists: A Report From the ACR Future Trends Committee

In response to the current era of rapid evolution of health care delivery and financing, radiologists are increasingly considering, as well as confronting, new practice models. Hospital employment is one such opportunity. Within this report to the ACR membership, the potential advantages and risks for radiologists considering hospital employment are examined.

Lateral Approach for Radiocarpal Wrist Arthrography

OBJECTIVE We describe a technique of radiocarpal arthrography using the lateral approach. This technique may be used as an alternative to conventional dorsal techniques. CONCLUSION Radiocarpal injection using the lateral approach can be considered as an alternative to conventional dorsal approaches in the evaluation of wrist pain and instability.

Craniocervical hyperpneumatization with concurrent pneumorrhachis, pneumomediastinum, and subcutaneous emphysema in a weightlifter.

BACKGROUND CONTEXT Acquired hyperpneumatization of the skull base and upper cervical vertebrae is extremely rare and is thought to occur in patients who habitually perform the Valsalva maneuver or engage in repetitive positive pressure activities such as scuba diving or free diving. Craniocervical hyperpneumatization has been reported to cause intracranial and extracranial pneumatoceles but is not generally considered as a cause of pneumorrhachis (air in the spinal canal). Pneumorrhachis is relatively rare, and usually occurs in a localized form, either in the cervical spine secondary to skull base fractures or in the thoracic spine secondary to pneumomediastinum or pneumothorax. Here, we report a case of extensive pneumorrhachis extending from the skull base to the thoracolumbar junction in association with marked axio-atlanto-occipital hyperpneumatization and pneumomediastinum. This unique constellation of findings likely resulted from complications of the Valsalva maneuver during strenuous exercise. PURPOSE To present a unique case of axio-atlanto-occipital hyperpneumatization with concurrent marked cervicothoracic pneumorrhachis, subcutaneous emphysema, and pneumomediastinum and to provide a review of the relevant literature, pathophysiology, and treatment strategies related to hyperpneumatization and pneumorrhachis. STUDY DESIGN/SETTING A unique case report from an urban medical center. PATIENT SAMPLE A single case. OUTCOME MEASURES Imaging findings and clinical history. METHODS Imaging data from a picture archiving and communication system and clinical data from an electronic medical record system were analyzed. RESULTS A 58-year-old previously healthy man presented with 3 to 4 weeks of neck pain, shoulder pain, and intermittent hand and finger numbness that developed after weightlifting. On physical examination, he had mild hyperreflexia and decreased pinprick sensation within the T5-T8 dermatomes. Initial radiographic and computed tomography (CT) studies demonstrated extensive craniocervical hyperpneumatization involving the occipital bone, clivus, and C1 and C2 vertebral bodies. There was also pneumorrhachis extending throughout the entire cervical and thoracic spine, which caused moderate dural compression. Pneumomediastinum and subcutaneous emphysema were present. Maxillofacial CT showed dehiscent bone involving the dens, atlas, and occipital bone, with adjacent soft-tissue gas and pneumorrhachis. He was managed conservatively and advised to stop performing the Valsalva maneuver during weightlifting. His symptoms resolved, and follow-up imaging showed complete resolution of pneumorrhachis and partial reversal of hyperpneumatization. CONCLUSIONS Craniocervical hyperpneumatization is a rare complication of the Valsalva maneuver. Most reported cases have involved only the skull base, or the skull base and C1, and many have been further complicated by microfractures leading to pneumocephalus or extracranial pneumatoceles. We present a unique case of extensive craniocervical hyperpneumatization that extended to the level of C2 and was complicated by microfractures causing severe pneumorrhachis. Concurrent pneumomediastinum in this case may have been an independent complication of the Valsalva maneuver, which could have contributed to pneumorrhachis. Alternatively, pneumomediastinum may have been caused by migration of gas through the neural foramen from the epidural space, driven by positive pressure generated by the one-way valve effect of the Eustachian tube during periods of exertion.

Advanced Medical Imaging Protocol Workflow—A Flexible Electronic Solution to Optimize Process Efficiency, Care Quality and Patient Safety in the National VA Enterprise

Radiologists routinely make decisions with only limited information when assigning protocol instructions for the performance of advanced medical imaging examinations. Opportunity exists to simultaneously improve the safety, quality and efficiency of this workflow through the application of an electronic solution leveraging health system resources to provide concise, tailored information and decision support in real-time. Such a system has been developed using an open source, open standards design for use within the Veterans Health Administration. The Radiology Protocol Tool Recorder (RAPTOR) project identified key process attributes as well as inherent weaknesses of paper processes and electronic emulators of paper processes to guide the development of its optimized electronic solution. The design provides a kernel that can be expanded to create an integrated radiology environment. RAPTOR has implications relevant to the greater health care community, and serves as a case model for modernization of legacy government health information systems.

Symptomatic Extraperitoneal Bladder Perforation Following Transurethral Bladder Surgery: Imaging with CT Urography

An 80 year-old man presented to his primary care physician with painless gross hematuria. He reported having intermittent episodes of pink urine containing small clots for about three months. He was initially treated with a single course of ciprofloxacin for presumed urinary tract infection. His symptoms did not improve with antibiotic therapy and he was then referred to our institution for a computed tomography (CT) urogram. CT urogram showed a 4 x 3.6 centimeter (cm) infiltrating solid mass along the left lateral posterior wall of the urinary bladder (Figure-1). Tumor also extended along the bladder dome. Prostate enlargement and bladder diverticula were also present. He was referred to the urology service and subsequently underwent transurethral resection of bladder tumor (TURBT) with fulguration. No intraoperative complications were noted and he returned to the recovery room in satisfactory condition on continuous bladder irrigation. Pathologic examination revealed a 5 cm transitional cell carcinoma with high grade growth pattern invading the deep muscular layer. On postoperative day one, the patient reported abdominal pain and general discomfort. Physical exam revealed a grossly distended abdomen which was tender to palpation with positive guarding and decreased bowel sounds. He Symptomatic Extraperitoneal Bladder Perforation Following Transurethral Bladder Surgery: Imaging with CT Urography _______________________________________________

Pseudolesion in segment IV A of the liver from vein of Sappey secondary to SVC obstruction

Pseudolesions in the liver are caused by unusual/altered hemodynamics of the liver and can be confused with a true hepatic mass. In superior vena cava (SVC) obstruction. there is recruitment of the cavo-mammary-phrenic-hepatic-capsule-portal pathway. and the venous blood follows the internal mammary vein, the inferior phrenic vein, the hepatic capsule veins, and the intrahepatic portal system. causing a hypervascular pseudolesion in segment IV A of the liver. Recognizing the classic appearances of this hypervascular pseudolesion from the vein of Sappey in a CT study of the abdomen has prognostic implications in directing further evaluation of the chest for SVC obstruction. We present a case of a 54-year-old HIV-positive male smoker in whom identification of the hypervascular pseudolesion from the vein of Sappey on the abdominal CT led to the diagnosis of SVC syndrome.

Intrapancreatic accessory spleen

Accessory spleens are common, usually asymptomatic, incidentally discovered congenital foci of splenic tissue. They occur most commonly near the splenic hilum, with almost 20% in or near the pancreatic tail. On contrast-enhanced computed tomography (CT), differentiation of an intrapancreatic accessory splenule (IPAS) from other pancreatic tail lesions such as islet cell tumors and metastatic disease can present a diagnostic challenge. A high index of suspicion on the part of the radiologist, based on the classic location with typical imaging features and a combination of cross-sectional imaging studies such as ultrasound, computed tomograph (CT), or magnetic resonance imaging (MRI) with nuclear medicine examinations, can confirm the diagnosis of intrapancreatic accessory splenule and prevent unnecessary biopsy and/or surgery.

Harlequin testicle and other uncommon pathologies masquerading at routine scrotal ultrasound.

Abstract Many scrotal conditions manifest similarly as pain, swelling, a palpable abnormality, or a combination of these symptoms. Most common scrotal pathologies have characteristic accompanying sonographic findings. Less common pathologies can have similar clinical presentations, and imaging with scrotal ultrasound is required to aid in proper diagnosis. This article focuses on several of these less commonly encountered scrotal pathologies—including testicular segmental infarction, scrotal filariasis, scrotal mesothelioma, seminiferous tubule fibrosis, and scrotal leiomyosarcoma—and compares and contrasts them to more routine diagnoses. Familiarity with both typical and atypical scrotal conditions is necessary to make accurate diagnoses at ultrasound to guide appropriate treatment and avoid unnecessary surgery.