The lumbar artery perforator flap: clinical review and guidance on image reporting

The lumbar artery perforator (LAP) flap is a relatively new procedure that can be utilized to manage lumbosacral defects in addition to reconstructing distal body parts as well, such as breast reconstruction. This fasciocutaneous flap is designed based on the LAPs small arteries that emerge from the lumbar arteries then move superficially piercing overlying tissues to perforate the lumbar fascia and supply the skin and subcutaneous tissue; However, anatomical and clinical studies regarding the LAP flap and its perforators are sparse in the literature, and the results are even contradicting. This article will discuss the LAP flap, the anatomy of its perforators, and the clinical aspects about its usage. In addition, we explore its preoperative imaging evaluation, and deliver a guide on image reporting and radiological data that will benefit the surgeon most during the procedure.

Osseous Pseudoprogression in Vertebral Bodies Treated with Stereotactic Radiosurgery: A Secondary Analysis of Prospective Phase I/II Clinical Trials

BACKGROUND AND PURPOSE

Osseous pseudoprogression on MR imaging can mimic true progression in lesions treated with spine stereotactic radiosurgery. Our aim was to describe the prevalence and time course of osseous pseudoprogression to assist radiologists in the assessment of patients after spine stereotactic radiosurgery.

MATERIALS AND METHODS

A secondary analysis of 2 prospective trials was performed. MRIs before and after spine stereotactic radiosurgery were assessed for response. "Osseous pseudoprogression" was defined as transient growth in signal abnormality centered at the lesion with a sustained decline on follow-up MR imaging that was not attributable to chemotherapy.

RESULTS

From the initial set of 223 patients, 37 lesions in 36 patients met the inclusion criteria and were selected for secondary analysis. Five of the 37 lesions (14%) demonstrated osseous pseudoprogression, and 9 demonstrated progressive disease. There was a significant association between single-fraction therapy and the development of osseous pseudoprogression (P = .01), and there was a significant difference in osseous pseudoprogression-free survival between single- and multifraction regimens (P = .005). In lesions demonstrating osseous pseudoprogression, time-to-peak size occurred between 9.7 and 24.4 weeks after spine stereotactic radiosurgery (mean, 13.9 weeks; 95% CI, 8.6-19.1 weeks). The peak lesion size was between 4 and 10 mm larger than baseline. Most lesions returned to baseline size between 23 and 52.4 weeks following spine stereotactic radiosurgery.

CONCLUSIONS

Progression on MR imaging performed between 3 and 6 months following spine stereotactic radiosurgery should be treated with caution because osseous pseudoprogression may be seen in more than one-third of these lesions. Single-fraction spine stereotactic radiosurgery may be associated with osseous pseudoprogression. The possibility of osseous pseudoprogression should be incorporated into the prospective criteria for assessment of local control following spine stereotactic radiosurgery.

Assessing vascular effects of adding bevacizumab to neoadjuvant chemotherapy in osteosarcoma using DCE-MRI

BACKGROUND

The purpose of this study was to assess the impact of bevacizumab alone and in combination with cytotoxic therapy on tumour vasculature in osteosarcoma (OS) using DCE-MRI.

METHODS

Six DCE-MRI and three (18)F-FDG PET examinations were scheduled in 42 subjects with newly diagnosed OS to monitor the response to antiangiogenic therapy alone and in combination with cytotoxic therapy before definitive surgery (week 10). Serial DCE-MRI parameters (K(trans), v(p), and v(e)) were examined for correlation with FDG-PET (SUV(max)) and association with drug exposure, and evaluated with clinical outcome.

RESULTS

K(trans) (P=0.041) and v(p) (P=0.001) significantly dropped from baseline at 24 h after the first dose of bevacizumab alone, but returned to baseline by 72 h. Greater exposure to bevacizumab was correlated with larger decreases in v(p) at day 5 (P=0.04) and week 10 (P=0.02). A lower K(trans) at week 10 was associated with greater percent necrosis (P=0.024) and longer event-free survival (P=0.034).

CONCLUSIONS

This is the first study to demonstrate significant changes of the plasma volume fraction and vascular leakage in OS with bevacizumab alone. The combination of demonstrated associations between drug exposure and imaging metrics, and imaging metrics and patient survival during neoadjuvant therapy, provides a compelling rationale for larger studies using DCE-MRI to assess vascular effects of therapy in OS.

Abstract P5-01-02: Role of FDG-PET/CT in Metastatic Staging of Newly Diagnosed Primary Breast Cancer

Background

FDG positron emission tomography/computed tomography (PET/CT) may accurately detect distant metastases during staging of primary breast cancer. However, the evidence is very limited. We retrospectively compared the sensitivity and specificity of PET/CT and conventional imaging (CT, ultrasonography, radiography, and skeletal scintigraphy) for the detection of distant metastases in patients with primary breast cancer. We also retrospectively tested the hypothesis that stage III disease detected by conventional imaging + PET/CT has a better prognosis than that detected by conventional imaging only.

Methods

To determine sensitivity and specificity, we used a database of 225 patients with primary breast cancer (2000-2009) for which PET/CT data existed. The presence or absence of distant metastases was determined based on histopathologic findings, subsequent imaging findings, or clinical follow-up. To determine prognosis, we studied 935 patients newly diagnosed with stage III breast cancer (2000-2009). In 82 of these patients, stage III disease was detected by conventional imaging + PET/CT. We studied 171 IBC patients newly diagnosed with stage III breast cancer. In 51 of these patients, stage III disease was detected by conventional imaging + PET/CT; we compared their relapse-free survival (RFS) and overall survival (OS) rates with those for 853 patients diagnosed using conventional imaging only. Univariate and multivariate Cox Proportional Hazard regression models were used to assess PEC/CT.

Results

Among 225 pts with primary breast cancer, the sensitivity and specificity for PET/CT in the detection of distant metastases were 97.4% and 91.2%, respectively; This was significantly higher (p=0.009 and P<0.001) than the sensitivity and specificity rates for conventional imaging only (85.9% and 67.3%, respectively). Eleven patients of distant metastases detected by PET/CT were clinically occult and not evident on conventional imaging. Among patients with stage III disease, RFS (hazard ratio [HR]=1.10, p=0.7) and OS (HR=1.14, p=0.673) did not significantly differ based on whether PET/CT was used. RFS also did not show significant difference in multivariate analysis (HR=0.70, p=0.213). However, in inflammatory breast cancer (IBC), patients diagnosed with conventional imaging + PET/CT had longer RFS than patients diagnosed with conventional imaging only in both univariate (HR=0.43, p=0.014) and multivariate analysis (HR=0.33, p=0.004). There was a trend for OS improvement among patients who had PET/CT (HR=0.55, p=0.122). Conclusion

PET/CT had higher sensitivity and specificity than conventional imaging in the detection of distant metastases of breast cancer. Among patients with stage III disease, there was no difference in OS or RFS between patients diagnosed with conventional imaging + PET/CT and patients diagnosed with conventional imaging only. IBC patients staged with conventional imaging + PET/CT had better prognosis than those staged with conventional imaging only. Based on our results, the use of PET/CT as a staging tool to detect metastasis is not justified in stage III non-IBC. Conversely, the use of conventional imaging + PET/CT in patients with IBC appears promising, but needs prospective confirmation.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-01-02.

MR imaging of periarticular soft-tissue lesions

The exquisite soft-tissue contrast and multi-planar imaging capabilities of MR imaging uniquely qualify this modality for the evaluation of periarticular pathology. MR evaluation can be diagnostic by signal characterization, as in a lipoma, or by anatomic location, as seen in meniscal and synovial cysts. In other less diagnostic pathology, MR imaging can focus a differential diagnosis, guide percutaneous or surgical biopsy, provide local staging, and serve as a surgical map.

Diagnostic radiology peer review: a method inclusive of all interpreters of radiographic examinations regardless of specialty

A proposed method of assessing the quality of diagnostic radiographic examinations includes peer review designed to evaluate physicians, including nonradiologists, involved in the performance and interpretation of such examinations. A pilot project evaluated this system with randomly selected Pennsylvania Blue Shield data files of 10 providers billing for chest radiography interpretations during the second quarter of 1989. Of the 98 chest radiographs reviewed blindly, all inadequately marked radiographs and incomplete written reports were produced by nonradiologists. Technical quality of images obtained by radiologists did not significantly differ from that of images obtained by nonradiologists (P = .189). All five interpretive errors that could have seriously affected the patient's health care were produced by nonradiologists (P = .019). Four of these serious errors were made by providers billing for fewer than 25 radiographs. While administrative and time cost limitations are obvious, this method of peer review encompasses all physicians billing for a particular radiographic service, irrespective of specialty.

The calcaneus: normal and abnormal

The calcaneus is the largest tarsal bone. Many congenital and acquired disorders affect the bone. Primary disorders arise in the calcaneus itself, whereas secondary disorders arising in the neighboring soft tissues extend into and affect the calcaneus indirectly. Among the primary lesions, congenital, traumatic, infectious, hematologic, neoplastic, and other miscellaneous disorders constitute the majority, whereas various arthritides and soft-tissue neoplasms that arise adjacent to the bone constitute the important secondary calcaneal disorders. Radiographic features of many disorders of the calcaneus are disease-specific and thus diagnostic. This article describes a wide spectrum of calcaneal disorders and illustrates their salient radiographic features. This knowledge should facilitate radiographic diagnosis of various calcaneal disorders encountered in clinical practice.

Parosteal osteogenic sarcoma arising in cranial bones: clinical and radiologic features in eight patients

Parosteal osteogenic sarcoma is a distinct surface bone tumor with a better prognosis than conventional osteogenic sarcoma. We studied eight histologically proved cases of cranial parosteal osteogenic sarcoma. The tumors were identical in histologic appearance to parosteal osteosarcoma arising in long bones. Clinically, the tumor presented as a hard, painless, nodular scalp mass. The prevalence in women outnumbered that in men by 3:1, with most cases occurring between the second and third decades of life. Plain radiographs showed a rounded, sessile bone growth of variable size arising from the outer table of the skull. The tumor was heavily ossified centrally with variable margins and, at times, with radiating bony spicules at the periphery. No satellite bone nodules were noted in adjacent soft tissues. In three cases a fine radiolucent cleft was demonstrated between the tumor and the underlying outer table on the tangential radiographs or CT. After en bloc resection of the tumor, follow-ups for 20 years in one patient and 1 year in two patients showed no recurrence. Parosteal osteosarcoma of the skull is a rare low-grade tumor that usually arises from the outer table of the skull and has distinctive radiologic features that should distinguish it from other exophytic cranial bone neoplasms.

Osteosarcomatosis

A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.

Fibrous lesions of bones

A large variety of benign and malignant fibrous lesions occur in the skeleton. Many fibrous bone lesions have characteristic features on plain radiographs and are easy to diagnose; others may pose significant difficulty. Most often, an osteolytic defect is seen associated with a fibrous lesion in the affected bone, although a mixed and sclerotic fibrous bone lesion is not unusual. Many benign fibrous bone lesions are asymptomatic; others become clinically apparent because of associated pathologic fracture or deformity of the involved bone. Malignant fibrous lesions tend to be aggressive, with focal bone destruction and adjacent soft-tissue involvement. The authors describe many fibrous bone lesions with their salient clinical and radiographic features.

The many faces of neuroblastoma

Neuroblastoma is a common tumor in childhood. It arises in the adrenal gland or in various extraadrenal primary sites of the sympathetic chain. Clinically, it may present as an abdominal mass or as disseminated metastatic disease. We studied 52 patients with neuroblastoma, and the typical and unusual radiographic features of the disease are presented.

Primary mucinous cystadenocarcinoma of the appendix with pseudomyxoma peritonei manifested as a splenic mass

We have reported a case of pseudomyxoma peritonei manifested as a splenic mass in a 38-year-old woman. Upon reviewing previously reported cases of pseudomyxoma peritonei with visceral involvement or extension above the diaphragm, we conclude that such spread of the disease does not significantly alter the prognosis. Furthermore, our findings support the concept that pseudomyxoma peritonei represents the implantation of malignant cells rather than metaplastic transformation of mesothelial cells.

The clavicle: normal and abnormal

The clavicle is an unusual long bone with many unique embryologic features. It is often involved in congenital and acquired disorders. Traumatic, inflammatory, neoplastic, metabolic and many other miscellaneous lesions may also affect the bone. Because of its ligamentous attachments and the presence of articulations at both ends, the clavicle can also be involved in arthritic diseases. This article illustrates the radiographic manifestations of many of the disorders of the clavicle that are commonly encountered in clinical practice.

Expansile bone lesions of the vertebra

Vertebral expansion may be caused by both benign and malignant disease processes. Recognition of such lesions on radiographs facilitates accurate diagnosis in many cases.

The vertebral body: radiographic configurations in various congenital and acquired disorders

Many abnormal vertebral configurations are disease-specific and when recognized on radiographs, make correct diagnosis possible.

An approach to primary bone tumors

This article is designed to provide the busy, practicing physician with the essential information needed to approach the patient with a primary bone tumor. An algorithm provides a suitable method of assessing most patients with bone tumors, recognizing slight modification is necessary in each case. Following this approach should allow successful accomplishment of the therapeutic triad: (1) do not "over-treat" a benign bone tumor, (2) do not "under-treat" a malignant bone tumor, and (3) do not misdirect the biopsy approach to the lesion so as to convert a more conservative operation into a more radical operation.

Rheumatoid and seronegative arthropathies of the foot

The foot is often involved in rheumatoid arthritis and its seronegative variants. This article presents an overview of the subject and highlights the various distinguishing features of these arthritic disorders in the foot.

Osteomyelitis, acute and chronic

In certain patient populations, osteomyelitis is a significant clinical problem. The judicious use of plain film radiographs and radionuclide bone imaging by the imaging consultant has a critical role in the early detection and diagnosis of osteomyelitis. This complementary imaging approach produces the highest and greatest accuracy in the documentation of skeletal infections. Inadvertent delay in the initiation of appropriate therapy can be obviated utilizing these imaging techniques and undue morbidity averted.

The normal and abnormal growth plate

Skeletal growth is a dynamic process. A knowledge of the structure and function of the normal growth plate is essential in order to understand the pathophysiology of abnormal skeletal growth in various diseases. In this well-illustrated article, the authors provide a radiographic classification of abnormal growth plates and discuss mechanisms that lead to growth plate abnormalities.

Multiple skeletal fibroxanthomas: radiologic-pathologic correlation of 72 cases

Out of a series of 900 biopsy-proven cases of skeletal "fibroxanthoma" (nonossifying fibroma, fibrous cortical defect), we studied 72 patients with more than one lesion. Age, sex, coexistent conditions such as neurofibromatosis, and histologic and radiographic appearance of the lesions were evaluated. Multiple skeletal fibroxanthomas are probably more common than previously suspected. (At least 8% of the 900 patients in our archives had multiple lesions). Only a small percentage (5%) of patients with multiple skeletal fibroxanthomas had coexistent neurofibromatosis. These lesions are histologically indistinguishable from their solitary counterparts and most commonly present in the lower extremities. Four radiographic patterns were noted: clustered lesions--usually about the knee. nonclustered lesions--in opposite ends of long bones. coalescent lesions--several lesions coalescing over time. This observation has not been previously reported. emergent lesions--lesions appearing in previously unaffected bone. Familiarity with these features may obviate biopsy.

Paget disease of the anterior tibial tubercle

A study was done of 13 cases of biopsy-proved Paget disease in which the disease involved the anterior tibial tubercle with extension into the metaphysis and diaphysis, but without apparent involvement of the proximal tibial epiphysis. Case data were obtained from archives containing more than 350 cases of Paget disease. Age, sex, symptoms, serum alkaline phosphatase level, and histologic and radiographic appearance of the lesions were evaluated. Patients were young at clinical presentation, averaging 36 years of age. In five of six patients the serum alkaline phosphatase level was normal. The proximal extent of the disease was the anterior tibial tubercle rather than the proximal epiphysis. Radiographic patterns ranged from predominantly lytic to mixed lytic and blastic to predominantly blastic, and the lesion was marginated by a flame-shaped configuration. The radiographic appearance of Paget disease of the anterior tibial tubercle is characteristic and should be sufficient to suggest the diagnosis and preclude biopsy.

Effects of MR imaging on murine natural killer cell cytotoxicity

To determine the effect of MR imaging on the immune system, 21 male C57BL/6 X DBA/2 F1 mice were exposed to MR imaging at a field strength of 0.15 T for 2 hr. Another nine mice (controls) were sham exposed for the same amount of time. Mice were sacrificed and their spleens removed 24, 72, and 144 hr after the exposure (MR or sham). Spleen cell suspensions were passed over nylon wool columns and then used as effector cells in a short-term natural killer cell cytotoxicity assay with 51Cr-labeled YAC-1 cells as target cells. The results showed no evidence of decreased cytotoxicity due to exposure to MR. On the contrary, at all three times after exposure and for all target-to-effector cell ratios, mean cytotoxicity was greater for MR-exposed groups than for sham-exposed groups. The results show that MR exposure has no adverse effect on the immune system, as evidenced by natural killer cell activity.

Benign cortical defect: site for an avulsion fracture

A benign cortical defect in a bone may present itself as a weak site for muscle attachment resulting in an avulsion injury. Such a benign cortical defect may be mistaken for a malignant tumor when the avulsion injury excites irregular, laminated periosteal reaction. We report three patients in whom avulsion fractures occurred at the site of pre-existing benign cortical defects in the distal femur.

Benign fibrous histiocytoma: a rare endobronchial neoplasm

Fibrous histiocytomas are rarely found within the lung and have presented as a mass within a major airway only twice previously. This is the third reported case of such a tumor visualized roentgenographically in an airway on the frontal chest film of a patient presenting with recurrent pneumonia.

Radionuclide bone scanning in giant cell tumor

Radionuclide bone scan findings are described and correlated with pathology in 23 patients with giant cell tumor (GCT) of the bone. The degree of radionuclide activity was markedly increased in 20 (87%), minimally increased in three (13%), and decreased in none of the patients. Of the 23 patients with increased radioactivity, the pattern was diffuse in 11 (48%) and doughnut in 12 (52%). Extended patterns of radioactivity were present in 19 of 22 patients; however, none were associated with true tumor extension. Bone scanning did not aid in the detection of GCT, was nonspecific, and did not differentiate benign from malignant GCT. Although radioactivity extended beyond the radiographic abnormality in the majority of patients, this was most likely secondary to other bony abnormalities or local and/or regional hyperemia, and caution should be taken in ascribing this extension to either tumor or metastasis.

Cadaver radiography in the teaching of gross anatomy

The authors describe a new teaching method for first-year medical students, involving preparation and use of cadaver radiographs in the gross anatomy laboratory. A standard series of radiographs of each cadaver was obtained prior to dissection and provided to each group of students. This technique offers a unique opportunity for radiographic/anatomical/pathological correlation, facilitates an understanding of complex anatomical relationships, and illustrates the application of anatomical knowledge to clinical practice. It can also generate intense student enthusiasm and improve student-faculty communication and teaching relationships.

Multilocular cystic nephroma: a radiographic-pathologic correlation of 58 patients

Clinical radiographic, and pathologic findings of multilocular cystic nephroma (MLCN) in 58 patients are presented. The lesion that affects predominantly boys in childhood and women in adulthood is usually solitary but rarely can be multiple, and it commonly occurs as an asymptomatic mass, occasionally with hematuria. Tumors may grow slowly over years or rapidly within months. A mass that is usually identified on plain radiographs occasionally has curvilinear calcification. Excretory urography and retrograde pyelography are helpful when pelvic herniation of the tumor is recognized, or when septae are noted with total body opacification. Angiography showed an avascular mass (six lesions), a hypovascular mass (14 lesions), or a hypervascular mass three lesions). Ultrasonography is helpful when multiple circumscribed sonolucent areas are identified. Similarly, a multilocular mass with septae is usually identified by computed tomography (six of seven cases). Our findings and a review of the literature indicate that this lesion is a neoplasm that can be strongly suspected preoperatively if pelvic herniation or a multilocular pattern is noted on imaging studies.

Role of radiology in the study and identification of casualty victims

Radiology is assuming an increasingly important role in the investigation of casualty victims. Radiographic screening for foreign bodies, personal effects, dental and surgical artifacts and occult skeletal injury has long been an established technique in forensic medicine. Positive radiographic identification of the victims by comparison with antemortem films and records is a more recent, important development. Large scale radiographic investigations may require improvised facilities posing unaccustomed technical and logistical problems. Radiologic experience gained from aviation accident investigation is found to apply in other casualty situations as well as in individual fatality investigations. Radiologic data may aid determination of the cause of incidents, resulting in improved safety procedures and design, as well as serving humanitarian and forensic functions.

Primary malignant renal tumors in the second decade of life: Wilms tumor versus renal cell carcinoma

Primary renal malignancies occur least frequently in the second decade of life. Of the 4,798 cases of renal cell carcinoma and Wilms tumor referred to the Armed Forces Institute of Pathology 53 renal cell carcinomas and 56 Wilms tumors occurred in the 10 to 20-year age group. Pathologically, both tumors in this age range are similar to those occurring at a more typical age, and histologic differentiation between renal cell carcinoma and Wilms tumor is seldom a problem. While radiographic evaluation is useful to characterize the neoplasm, evaluate the contralateral kidney and detect the presence of tumor extension, current imaging techniques cannot confidently distinguish these 2 tumors.

Paget disease of the hand: radiographic spectrum

Paget disease uncommonly affects the hand. When it does, radiographic findings are same as when the disease occurs elsewhere. Eleven new cases that demonstrate four predominant radiographic patterns are described: homogeneous sclerosis, trabecular coarsening, cortical thickening, and lysis. The homogeneous sclerosis pattern was associated with monostotic hand disease. One patient developed bilateral phalangeal osteosarcomas. In every case, the disease process extended to the subarticular region and the affected bone was enlarged. With one exception, both ends of the bone were involved.

Radiologic and pathologic analysis of solitary bone lesions. Part I: internal margins

The interface between tumor and bone that is displayed radiographically is a zone of cellular activity. Its radiographic appearance represents the summation of bone lysis and production. This activity and the radiographic details of the resultant margin are an index of the biologic activity of a lesion. The anatomic site and extent of the lesion can be assessed by radiographs and special imaging techniques. Careful analysis of these patterns, when integrated with clinical data, enhances diagnosis, patient management, and therapy.

Radiologic and pathologic analysis of solitary bone lesions. Part II: periosteal reactions

The activated periosteum has a deceptive anatomic constancy amidst change. The change involves the production of matrix and, in the process, proliferation and expenditure of cells. When the demand for a reaction is excessive, nearby extraperiosteal soft tissue serves as a ready source for additional modulating cells, just as it does for fracture callus. The configuration of a periosteal reaction is an index of the nature and intensity of the inciting process.

Radiologic and pathologic analysis of solitary bone lesions. Part III: matrix patterns

The mineralized matrix patterns demonstrated in clinical radiographs of primary bone neoplasms and related disorders help to predict matrices, and have diagnostic significance. These radiographic patterns may yield important clues as to the true nature of a lesion, especially when only limited biopsy material is available from extraosseous or nonrepresentative areas. Therefore, in the evaluation of bone tumors and tumor-like conditions, it is of extreme importance to correlate the histologic findings with the radiographic examination and to know precisely the location at which the biopsy material was obtained. Patterns of mineralization may be the only remnants of a pre-existing lesion that has undergone sarcomatous transformation, such as in bone infarcts, enchondromas, or osteochondromas. The pre-eminent item of importance for patient care is the diagnosis of a malignant process. However, failure to appreciate antecedent benign conditions will not contribute toward a better understanding of tumor biology or a determination of those benign lesions that warrant removal or close clinical follow-up. Integration of matrix data with knowledge of the anatomic location of a lesion, the character of its margins, and the periosteal reaction patterns it produces permits prognostication and often, specific diagnosis.

Angiomyolipoma: computed tomographic-pathologic correlation of 17 cases

The angiomyolipoma is a benign renal tumor composed of fat, smooth muscle, and abnormal blood vessels. The tumor often extends into the perinephric space and often is complicated by intratumoral or perinephric hemorrhage. The CT findings of 17 cases of angiomyolipoma were correlated with their pathologic findings and are described. CT scans usually demonstrate a large fatty mass intermixed with areas of tissue density which may represent nonfatty parts of the tumor or areas of hemorrhage. CT is more sensitive than plain films at detecting the fat within the angiomyolipoma. CT is also useful in identifying perinephric extension and hemorrhage. In those angiomyolipomas composed primarily of smooth muscle or in which intratumoral hemorrhage has obscured the fatty part of the tumor, the CT appearance is indistinguishable from other solid renal tumors.

Angiomyolipoma: ultrasonic-pathologic correlation

Previous reports of angiomyolipoma have emphasized the ultrasonic finding of a very echogenic intrarenal mass. Ten cases of angiomyolipoma for which ultrasound examinations were available were retrospectively reviewed and correlated with their pathologic findings, and, when available, with computed tomographic findings to determine if other sonographic patterns could be recognized. In addition to the typical echodense pattern (six cases), a mixed pattern (two cases) and a low sonodense pattern (two cases) were discovered. To determine if the typical echodense pattern is specific for angiomyolipoma, 42 cases of renal cell carcinoma for which ultrasound examinations were available were also retrospectively reviewed. In two cases of renal cell carcinoma echodense patterns that were indistinguishable from those of angiomyolipoma were found. Two conclusions are reached: (a) there is a spectrum of ultrasonic findings with angiomyolipoma, and (b) the presence of an echodense intrarenal mass, although very suggestive of angiomyolipoma, is not pathognomonic.

Mesoblastic nephroma: radiologic-pathologic correlation of 20 cases

The mesoblastic nephroma is a benign renal tumor that usually appears as a neonatal abdominal mass. The tumor is composed of connective tissue that grows between nephrons and usually replaces most of the renal parenchyma. Radiographic and sonographic images reflect this cellular composition and unique growth pattern. The radiographs of 20 cases of mesoblastic nephroma were correlated with their pathologic findings and are described. Urograms usually demonstrate an intrarenal mass two to seven times larger than the contralateral kidney. Contrast medium is occasionally demonstrated within the tumor and may represent function by nephrons trapped within the mesoblastic nephroma. Sonographic studies correlate well with the gross morphology and may be useful in establishing the relation of the tumor to the kidney. Some neovascularity is present on angiographic examination and most tumors are hypervascular. Prognosis after complete excision is excellent and adjunctive therapy is unnecessary.

Role of radiology in aviation accident investigation

Radiographic screening of fatality victims for skeletal detail, dental and surgical artifacts, personal effects, and foreign bodies is of established value. Radiography as the primary means of positive victim identification, through comparison with antemortem films and records, is an important new role. Data on sources of injury and relationships between victims and the crash environment may be derived from radiographic injury patterns and may be correlated with mechanisms of injury production. The result of such analysis is improved safety design. Such radiography poses unique technical and logistical problems, often involving temporary or remote facilities, which must be solved with consideration for privacy and safety. Advance planning is essential for maximum benefit from radiographic investigation.

Traumatic splenic cyst: radiologic-pathologic correlation from the Armed Forces Institute of Pathology

Traumatic splenic cyst is one of many diagnostic choices when a mass is found in the left upper quadrant. In the appropriate clinical setting, demonstration of an intrasplenic, unilocular, avascular, homogeneous, fluid-filled mass with a smooth, sharply marginated wall should suggest a splenic cyst. On pathological examination, an epithelial lining implies a developmental origin. More commonly, no such lining is found and old trauma is assumed to be the etiology.