Ovarian metastases: computed tomographic appearances

Computed tomographic scans of 34 patients with ovarian metastases were reviewed to assess the radiographic appearances and to correlate these with the primary neoplasms. Primary neoplasms were located in the colon (20 patients), breast (six), stomach (five), small bowel (one), bladder (one), and Wilms tumor of the kidney (one). The radiographic appearance of the metastatic lesions could be described as predominantly cystic (14 lesions), mixed (12 lesions), or solid (seven lesions). There was one false-negative examination which showed no ovarian enlargement, although neoplastic deposits were found on the ovary at laparotomy. The cystic and mixed lesions tended to be larger in overall diameter than the solid. The metastases from gastric carcinoma appeared solid in four of five cases. The metastases from the other neoplasms had variable appearances simulating primary ovarian carcinoma.     

The computed tomographic appearances of cherubism

The computed tomographic (CT) aspects of six cases of cherubism are described. Through its optimal representation of the lesions, CT enabled certain characteristics of this disease to be substantiated, namely, limitation of the process to the bones of the jaw and primarily superficial development of the mandibular lesions, coupled with an unusual mandibular condylar impairment. Moreover, the composition of this series permitted investigation of the condition in its several stages of progression.     

Pigmented villonodular synovitis of the knee: computed tomographic appearances

Five patients with pigmented villonodular synovitis (PVNS) of the knee demonstrate the value of preoperative, contrast medium-enhanced CT scanning. The technique is shown to be particularly useful in locating recurrent lesions and in demonstrating that popliteal and posterior calf masses are due to PVNS affecting the knee joint itself. In two of the five patients PVNS was not considered a possibility before the CT scan, and none had evidence of bone erosion on plain radiographs. In none of the patients was the unenhanced CT scan able to demonstrate evidence of decreased radiolucency due to fat within the tumour or density greater than the adjacent skeletal muscle, indicating haemosiderin deposits.     

The computed tomographic appearances of lymphangiectasia in the pelvis

We describe the CT appearances of lymphangiectasia in the pelvis of a 21-year-old male who presented with fever, abdominal pain and swelling of the right thigh. Previous histological examination of a biopsy specimen from the patient's thigh had demonstrated lymphangiectasia.     

Three-dimensional computed tomographic imaging of complex congenital cardiovascular abnormalities

Primary evaluation of congenital cardiac abnormalities traditionally relies upon echocardiography and conventional angiography, both of which have potential limitations. Echocardiography is an operator dependant study, limited by a small window and patient movement. Conventional angiography is an invasive procedure with an inherent risk of catheter complication such as vessel damage, bleeding, stroke and infection. During angiography, overlapping of the pulmonary and systemic circulation often provides a confusing picture given complex anatomy. Another limiting factor of particular significance in young children is radiation dose and contrast administration during catherization procedures. Three-dimensional MDCT provides an alternative to alleviate these pitfalls of traditional cardiac diagnostic studies. Development of multi-detector computed tomography (MDCT) and 3D software provides new methods for non-invasive visualization and evaluation of congenital cardiac abnormalities. The multiplanar, volumetric functions allow faster and more complete computed tomography diagnosis and better understanding of clinical relevance of complex cardiac anatomy. In addition, 3D imaging is particularly useful for preoperative planning and postoperative outcomes. This essay provides case studies to illustrate the usefulness of MDCT/3D CT for evaluation of complex congenital heart disease.     

The computed tomographic appearances of benign hepatic hamartoma

The case of a 32-year-old female with asymptomatic hepatomegaly due to a large cystic liver mass is described. Pathological examination after total excision revealed a benign hepatic hamartoma. Benign hepatic hamartoma is a rare cause of a cystic liver mass, usually occurring below the age of 5 years. The computed tomography findings included 'daughter cysts' and it is emphasised that these must not be regarded as pathognomonic of hydatid disease.     

Traumatic injuries: imaging of facial injuries

Facial injuries are common and require radiologic evaluation to plan treatment. The role of imaging is to detect fractures, describe their morphology and topography, and evaluate adjacent soft tissue damage. Computed tomography is the imaging method of choice for an accurate diagnosis and for depicting the complex anatomic structures of the maxillo-facial region. Magnetic resonance imaging plays a limited role, mainly in the assessment of lesions of orbital soft tissues. This paper reviews the most common traumatic injuries of facial bones, paranasal sinuses, orbits and mandible.     

Traumatic injuries: imaging of head injuries

Due to the forces of acceleration, linear translation, as well as rotational and angular acceleration, the brain undergoes deformation and distortion depending on the site of impact of traumatizing force direction, severity of the traumatizing force, and tissue resistance of the brain. Linear translation of accereration in a closed-head injury can run along the shorter diameter of the skull in latero-lateral direction causing mostly extra-axial lesions (subdural hematoma,epidural hematoma, subarachnoidal hemorrhage) or quite pronounced coup and countercoup contusions. Contusions are considerably less frequently present in medial or paramedial centroaxial blows (fronto-occipital or occipito-frontal). The centroaxial blows produce a different pattern of lesions mostly in the deep structures, causing in some cases a special category of the brain injury, the diffuse axonal injury (DAI). The brain stem can also be damaged, but it is damaged more often in patients who have suffered centroaxial traumatic force direction. Computed tomography and MRI are the most common techniques in patients who have suffered brain injury. Computed tomography is currently the first imaging technique to be used after head injury, in those settings where CT is available. Using CT, scalp, bone, extra-axial hematomas, and parenchymal injury can be demonstrated. Computed tomography is rapid and easily performed also in monitored patients. It is the most relevant imaging procedure for surgical lesions. Computed tomography is a suitable method to follow the dynamics of lesion development giving an insight into the corresponding pathological development of the brain injury. Magnetic resonance imaging is more sensitive for all posttraumatic lesions except skull fractures and subarachnoidal hemorrhage, but scanning time is longer, and the problem with the monitoring of patients outside the MRI field is present. If CT does not demonstrate pathology as can adequately be explained to account for clinical state, MRI is warranted. Follow-up is best done with MRI as it is more sensitive to parenchymal changes. In routine MR protocol gradient-recalled-echo sequences should be included at any other time after a traumatic event since they are very sensitive in detection of hemosiderin as well as former hematoma without hemosiderin. The MR signal intensity varies depending on sequences and time scanning after trauma.     

Traumatic injuries: imaging of spinal injuries

Severe (high-energy) spinal injuries are common sequelae of acute traumas. The task of radiology is to establish the radiological diagnosis, classify it, judge stability and instability and lead further radiological evaluation in cases of non-agreement between the radiological diagnosis and the clinical (neurological) findings. While skeletal abnormalities are best diagnosed with spiral CT and to a lesser degree with plain-film radiographs, soft tissue lesions, such as cord injuries or ligament ruptures, are best outlined with emergency MRI. The classification of fractures depends on fracture (trauma)-biomechanics and location. All these efforts are necessary to get the best clinical outcome for the patient.     

Traumatic injuries: imaging of thoracic injuries

Chest trauma is one of the most important causes of death, in particular in individuals under the age of 40 years. The mortality rate for chest trauma, often related to motor vehicle accidents, is approximately 15.5%; it increases dramatically to 77% with associated shock and head injury (Glasgow scores of 3-4). The accurate diagnosis of pathologies consequent to blunt chest trauma depends on a complete knowledge of the different clinical and radiological manifestations. The first diagnostic approach is classically based on chest X-ray often carried out on supine position at the hospital admission. A CT study must then be performed in all chest trauma patients in whom there is even the smallest diagnostic doubt on plain film. In particular, spiral CT (SCT) assumes a fundamental role in the demonstration of mediastinal hemorrhage and direct signs of aortic lesions. At present, SCT is routinely part of a diagnostic evaluation which also includes scans of the brain and the abdomen in polytraumatized patients. Magnetic resonance is the ideal method for visualizing diaphragmatic lesions. Furthermore, recent reports have demonstrated the high diagnostic value of MR in evaluating aortic injuries. The purpose of this article is to review the most common radiological patterns related to chest trauma.     

Traumatic rupture of the gravid uterus: computed tomographic evaluation

In this report, we describe the computed tomographic findings of a ruptured gravid uterus in a 19-year-old woman involved in a motor vehicle accident. The associated maternal and fetal injuries as well as the likely mechanism of injury are discussed.     

Traumatic injuries: imaging of peripheral musculoskeletal injuries

The current dominant role of conventional radiography must be reassessed at increasingly shorter intervals in view of the continuing emergence of new imaging modalities that are available to diagnose peripheral musculoskeletal injuries. In comparison with conventional radiography, digital radiographic techniques offer advantages for optimization of image quality and dose, such as a wider dynamic range and post-processing of images. Currently, digital luminescence radiography (storage phosphor radiography) is the most commonly used digital method for obtaining radiographs, using the established positioning projections and routines of the film-screen technique. A new process, radiography with flat-panel amorphous silicon detectors, is still under development. Computed tomography is a valuable tool for diagnosing injuries of the peripheral musculoskeletal system, especially when three-dimensional data sets are acquired; these allow reformating images in all planes desired (2D technique) or in a volumetric format (3D technique). Established indications for CT in the peripheral skeleton are hip fractures, wrist injuries and calcaneal fractures; however, CT may be used as a supplement to radiography in every region of the body. Sonography is beginning to play an increasingly important role in trauma. Muscle and tendon injuries are the most common indications, but worthwhile information can be gained of the shoulder, elbow, hip, and knee joints, supplementing conventional or digital radiography. Magnetic resonance imaging effectively visualizes traumatic changes of the skeleton and the peripheral soft tissues. It is the method of choice to detect occult fractures. It can be used to diagnose muscle and tendon injuries. Joint injuries, especially in the knee and the shoulder joint, are common indications for MRI in the posttraumatic setting.     

Primary choroid plexus papilloma of the cerebellopontine angle: magnetic resonance imaging, computed tomographic and angiographic appearances.

The computed tomographic, angiographic and magnetic resonance imaging (MRI) appearances of a benign primary choroid plexus papilloma of the cerebellopontine angle are reported. Although benign, this tumour showed local invasion of the petrous temporal bone and mastoid air cells. The differential diagnosis of cerebellopontine angle lesions is discussed. Papilloma is suggested by the presence of a vascular, calcified, enhancing extra-axial mass in or around the cerebellopontine angle. MRI may show evidence of high vascularity and internal haemorrhage. Differentiation from other cerebellopontine tumours, most particularly meningioma, may not be possible on radiological features.     

The varied computed tomographic appearances of acute spinal epidural haematoma

Two cases are reported of surgically confirmed acute spinal epidural haematoma demonstrated by computed tomography at the time of presentation. Five distinct appearances were encountered. The variable morphology and the role of computed tomography in diagnosing this condition are discussed.