Jaw osteonecrosis in patients treated with bisphosphonates: MDCT evaluation

PURPOSE

This study was done to evaluate the use of multidetector computed tomography (MDCT) in the evaluation of jaw osteonecrosis, a recently described medical entity in patients receiving long-term intravenous or oral bisphosphonates, and to help radiologists recognise it to enable early diagnosis and appropriate management.

MATERIAL AND METHODS

Thirty-eight patients with a history of neoplasm (breast, prostate, multiple myeloma, pancreas) or osteoporosis and bisphosphonate use and recent oral surgery who presented with pain in the mouth and temporomandibular joints, soft tissue infections, altered taste and numbness were examined with MDCT.

RESULTS

In all patients, MDCT revealed the presence of structural bony alterations referable to osteonecrosis associated with orosinusal fistula in four of them and bony intraoral spicules in 25.

CONCLUSIONS

Jaw osteonecrosis is an established medical entity discovered in patients who have undergone treatment with bisphosphonates and dental extraction or other oral surgery. MDCT with multiplanar (MPR), volume rendering (VR) and three-dimensional (3D) reconstructions allows accurate assessment of affected bone structures, enabling early diagnosis and suitable treatment planning. Radiologists should be aware of the risk of osteonecrosis in patients treated with bisphosphonates and be able to distinguish it from other bone diseases (osteomyelitis and osteoradionecrosis) with which it enters the differential diagnosis.

Helical CT angiography in gastrointestinal bleeding of obscure origin

OBJECTIVE

The aim of the study was to verify the usefulness of helical CT angiography for diagnosis of gastrointestinal hemorrhage of obscure origin.

SUBJECTS AND METHODS

Eighteen consecutive patients underwent catheterization of the abdominal aorta followed by helical CT angiography before and after intraarterial injections of a contrast medium. Helical CT angiography revealed the site of hemorrhage as an extravasation of contrast medium resulting in a hyperdense area in the intestinal lumen. All patients then underwent conventional angiography that was selective for the 13 patients in whom helical CT angiography was positive and standard for the remaining five patients with negative helical CT angiograms.

RESULTS

Helical CT angiography revealed the site of hemorrhage in 13 (72%) of 18 patients. Diagnosis of bleeding site was confirmed, and the cause was established at surgery in 11 of these 13 patients. The site of bleeding for the remaining two patients was confirmed by angiography as angiodysplasia of the jejunum (n = 1) and of the colon (n = 1). Of the five patients with negative helical CT angiograms, location of bleeding was revealed by conventional angiography in two patients; one of the remaining three patients underwent exploratory laparotomy; and bleeding ceased in the remaining two patients, who were treated without surgery. Conventional angiography was negative for two of the 13 patients in whom helical CT angiography was positive.

CONCLUSION

Despite our limited experience, helical CT angiography proved to be an easier and faster technique than conventional angiography for localizing gastrointestinal bleeding of obscure origin and useful as a guide for subsequent selective conventional angiography.

[Spiral computed tomography with arteriography in the diagnosis of digestive system hemorrhages of obscure origin]

Some 5-20% of gastrointestinal (GI) bleeding cases are of obscure origin because bleeding is difficult to diagnose or locate with conventional imaging methods. The authors suggest arterial spiral CT (ASCT) of the abdomen as an original tool to study GI bleeding of obscure origin. This diagnostic method consists of two subsequent phases: first, after abdominal aorta catheterization, the catheter is positioned in the celiac artery; then, CT of the abdomen is performed before and after intra-arterial contrast agent injection. In 6 of 10 patients with GI bleeding of obscure origin, ASCT depicted small high-intensity areas in the intestinal lumen, which indicate a source of bleeding. The site of bleeding was studied only with topographic criteria according to scanning planes, and the morphological features of the intestinal segments were investigated. All patients were submitted to surgery: when ASCT identified a bleeding site, angiography was limited to the involved arterial district. Angiography alone could locate the source of bleeding in 5 patients; angiography and ASCT were in agreement in 4 patients. The combined techniques located the source of bleeding in 7/10 patients and the nature of bleeding was diagnosed in 3/10 patients (angiodysplasia). Even though their experience is limited, the authors believe that ASCT can be useful in locating GI bleeding of obscure origin, as well as in guiding subsequent selective angiography.

[Classification, significance and sequelae of posttraumatic "occult" bone and cartilage fractures of the knee. The role of magnetic resonance]

Magnetic Resonance Imaging (MRI) shows, in the post-traumatic knee, a fairly high number of bone and cartilage injuries missed by conventional radiography and therefore called occult. Our aim is to classify these injuries, to correlate their site and distribution with associated menisco-ligamentous injuries and with trauma mechanisms. Thirty-eight patients with a history of acute knee trauma and negative X-ray findings were examined with MRI within 15 days of trauma. 1.5- and 0.5-T units and SE T1-weighted GE T2*-weighted and SE T2-weighted sequences were used. The injuries were classified as intraosseous and osteochondral bruises or fractures. Twenty-three patients with menisco-ligamentous injuries were submitted to therapeutic arthroscopy; the sites of bone and cartilage injuries depicted with MRI were studied with arthroscopy. Seven patients were followed-up with MRI at 6-12 months to investigate subchondral injury evolution: 5 of 7 patients were also submitted to arthroscopy. MRI showed a statistically significant correlation between site and distribution of bone and cartilage injuries and between internal derangement and trauma mechanisms, i.e., contusion, distortion, stress. In our experience, MRI could identify and characterize occult subchondral injuries, thus allowing appropriate treatment.

[Computerized tomography in the staging and the follow-up of Hodgkin's lymphoma of the thorax]

As yet, the role of Computed Tomography (CT) as a routine imaging technique in the staging and follow-up of thoracic Hodgkin's disease has not been assessed. The authors report the results obtained in 120 patients affected with thoracic Hodgkin's disease, staged and followed by means of chest X-rays and CT. CT better identified intrathoracic involvement of mediastinal nodes, of lung parenchyma, of pleura, and of pericardial and chest walls in 54/120 patients (45%), with staging modifications in 18 (15%) of them only. Treatment was changed only in 12 patients (10%) where radiation therapy had been planned. The clinical value of the additional information yielded by CT was especially evident in the follow-up: CT allowed the correct evaluation of persistent/recurrent disease in 51/117 patients (43.5%), a figure high enough to suggest the use of CT in the routine follow-up of patients affected with thoracic Hodgkin's disease.

[The role of lymphography in melanoma of the limbs. Personal experience]

The authors report the results of the lymphographic examinations performed on 123 patients affected with melanoma of the limbs. The patients were divided into 2 groups according to the different clinical stages; they all had pathologic confirmation. The following lymphographic parameters were considered: sensitivity, specificity, efficacy and positive/negative predictive value. The results obtained in the first group of patients (clinical stage: I) demonstrated lymphography to have low sensitivity, specificity and efficacy in the staging of melanomas (37%, 50% and 45%, respectively). On the contrary, lymphography could be trusted in the study of stage II melanomas thanks to its high sensitivity. As for stage III, the methodology had a clinical indication only in the follow-up of melanomas treated with radiochemotherapy.

[A new CT technic in the study of intracanalicular neurinoma of the acoustic nerve. Preliminary report]

A preliminary report is presented on a new technique for the detection and the diagnosis of intracanalicular acoustic neuromas. The technique consists of preliminary CT scans on petrous bones, after iv administration of a bolus of contrast medium. The scans are performed at a predetermined level of the middle portion of the internal auditory canals. The early enhancement is then evaluated of the soft tissues contained into the auditory canal on the side with retrocochlear neurosensory hypoacusis. The images obtained are then processed by an image processing program, thus enhancing the contrast resolution and allowing an optimal depiction of the lesion. In the past 10 months, 67 patients with clinical suspicion of acoustic neuromas were studied. This technique allowed the diagnosis of 2 acoustic neuromas with a purely intracanalicular involvement.