Conventional radiography, CT, and MR imaging in patients with hyperflexion injuries of the foot: diagnostic accuracy in the detection of bony and ligamentous changes

OBJECTIVE: The goal of this study was to compare the capabilities of conventional radiography, CT, and MR imaging in revealing ligamentous and bony changes in patients after hyperflexion injuries. SUBJECTS AND METHODS: Forty-nine patients with hyperflexion injuries of the foot were included in our study. Conventional radiography, weight-bearing radiography, CT, and MR imaging were performed. All images were reviewed with respect to ligamentous and bony abnormalities and alignment alterations. Eleven patients with joint malalignment underwent surgery, which is considered the gold standard in these patients. Five patients with joint malalignment refused surgery. RESULTS: For all 49 patients, conventional radiographs revealed 33 metatarsal and 20 tarsal fractures. Eight patients presented with tarsometatarsal joint (Lisfranc's joint) malalignment. Weight-bearing radiographs showed joint malalignment in the same eight patients only. CT showed 41 tarsal fractures and 53 metatarsal fractures. Joint malalignment was evident in 16 patients. MR imaging revealed 41 metatarsal fractures and 18 metatarsal bone bruises. Tarsal bones were fractured at 39 sites and there were nine tarsal bone bruises. Metatarsal fractures were mostly localized in the second metatarsal bone; tarsal fractures, in the cuboid. Joint malalignment was evident in 16 patients; in 11 of these 16 patients, Lisfranc's ligament was disrupted. Surgery confirmed bony and ligamentous changes and joint malalignment in 11 patients. CONCLUSION: Conventional radiographs including weight-bearing images are not sufficient for routine diagnostic workup of patients with acute hyperflexion injuries of the foot. CT should serve as the primary imaging technique for such patients.     

Radiation-induced osteosarcoma of the chest wall

A case of radiation-induced sarcoma of the chest wall is reported. Twenty-seven years 11 months after orthovoltage radiotherapy of the right breast a 69-year-old woman developed a radiation-induced osteosarcoma of the right thoracic wall. Initial diagnosis has been T-cell lymphoma of the skin. The right breast was irradiated with tangential fields and a total dose of 40 Gy, 2 Gy/day, 5 days a week. Orthovoltage treatment was performed in two courses of 20 Gy, 3 months apart. The clinical appearance of the secondary sarcoma was a diffuse infiltrated area in the irradiated breast which seemed to be fixed to the chest wall. Magnetic resonance imaging (MRI) demonstrated a mass in the right anterior thoracic wall which destroyed the fourth to the sixth rib. The tumor infiltrated the thoracic wall, including subcutaneous tissue and pericardium, as well as extending into the subphrenic space. Biopsy of the lesion revealed a poorly differentiated osteosarcoma. The patient's general condition precluded surgical or chemotherapeutic intervention; she died due to a cerebral stroke 6 months later. This case fulfilled all criteria for radiation-induced sarcoma, as there was a prior history of radiotherapy, latency period of several years, development of sarcoma within the irradiated field, and histologic confirmation of sarcoma.     

Cerebral schistosomiasis: MR and CT appearance.

After returning from Africa, a 54-year-old man began to have episodes of headache and nausea, then a cerebral convulsion. Clinical and laboratory findings and response to chemotherapy indicated the diagnosis of cerebral schistosomiasis. Three lesions were seen on CT and MR studies: two appeared to be subacute intracerebral hematomas, one in the right parietal lobe and one in the frontal lobe; the third lesion, in the cortex of the left occipital lobe, appeared to be a cyst. These lesions could represent small granulomatous tissue reactions with secondary hemorrhages.     

Correlation between inflection of heart rate/work performance curve and myocardial function in exhausting cycle ergometer exercise

Summary The heart rate/work performance (f _c/W) curve is usually S-shaped but a flattening at the top is not always seen. By means of radionuclide ventricular scintigraphy, the left ventricular ejection fraction (LVEF) of 15 sports students was investigated. The behaviour of the f _c/W curve during cycle ergometry with increasing exercise intensities was examined. During exercise, the LVEF showed a distinct initial increase reaching roughly constant values at stress levels below-maximum, and sometimes even falling again. The inflections of the f _c/W curve and left ventricular ejection fraction/performance curve (LVEFPC) were calculated from a second degree polynomial fit. From this function, the slopes of the tangents at the points of aerobic threshold and maximum performance were calculated together with the differences of the angles as a measure of the f _c/W curve and LVEFPC inflections. It follows that the f _c/W curve inflection became less pronounced or was even absent altogether when the decrease in LVEF towards the end of the ergometer exercise became more distinct. A significant negative correlation was found between the existence and extent of the f _c/W curve inflection and the stress-dependent myocardial function, expressed as the inflection of the LVEFPC (P<0.01, r=0.673). Thus, it would seem that the absence of a f _c/W curve inflection was related to a diminished stress-dependent myocardial function.     

Vascular complications in lumbar disk surgery: report of four cases

Vascular injuries in lumbar disk surgery, although rare, are serious complications which may be overlooked due to a broad range of clinical manifestations. It is important that surgeons and radiologists be aware of these potentially fatal complications and develop an appropriate symptom-based diagnostic paradigm. We reviewed 8099 consecutive cases of lumbar disk surgery, performed over a 14-year period at a single institution, for postoperative vascular complications. We identified four patients (0.05%) with lumbar disk surgery-related vascular complications: intraoperative lacerations of the abdominal aorta and median sacral artery, an arteriovenous fistula between the left common iliac artery and vein detected 19 days postdiskectomy, and a partially thrombosed aortic aneurysm with an arteriovenous fistula between the aneurysm and the inferior vena cava, diagnosed 11 months after surgery. The majority of cases in the literature of vascular injury in lumbar disk surgery were reported prior to 1965. Diagnostic approaches described in that period do not reflect the great range of diagnostic techniques available today. Angiography remains the gold standard for diagnosis and guidance as to surgical repair. However, a high index of suspicion based on clinical signs and/or the use of sonography or CT is important in the detection of these complications.     

Multi-detector CT urography: effect of oral hydration and contrast medium volume on renal parenchymal enhancement and urinary tract opacification—a quantitative and qualitative analysis

Objective

To assess the effect of oral hydration and contrast-medium volume on renal enhancement and urinary tract opacification in multi-detector CT urography.

Methods

A total of 192 patients were assigned to different protocols with varying doses of contrast agent with and without oral hydration. The attenuation was measured in the renal parenchyma in the unenhanced, nephrographic and excretory phase, and in the urinary tract in excretory phase imaging, respectively. Opacification of the urinary tract was graded on volume rendered images.

Results

Oral hydration did not significantly alter renal parenchymal enhancement in both the nephrographic and the excretory phase (p?>?0.001), but significantly decreased mean attenuation of the urinary tract in the excretory phase (p?≤?0.001), and improved continuous opacification of all ureter segments (p?<?0.01). Higher volumes of contrast medium improved renal parenchymal enhancement (p?≤?0.001) and continuous opacification of the urinary tract (p?≤?0.01).

Conclusion

Oral hydration leads to lower attenuation values in the urinary tract but improves the continuous opacification of the tract. Increase in contrast medium volume leads to higher renal parenchymal enhancement as well as to an increased continuous opacification of the urinary tract. Decrease in contrast medium volume cannot be compensated for by oral hydration in terms of parenchymal enhancement.     

Prevention of epidural scarring after microdiscectomy: a randomized clinical trial comparing gel and expanded polytetrafluoroethylene membrane

A randomized clinical trial compared two materials used to prevent epidural scarring after microdiscectomy. To determine whether ADCON®-L Gel (ALG) or Preclude Spinal Membrane® (PSM) was more effective in preventing scarring, reducing pain, and improving quality of life postoperatively. Postdiscectomy syndrome may result from epidural scarring. Various materials have been used in attempts to prevent this problem, but none have provided optimal results. Previous laboratory and clinical studies have found ALG and PSM to be effective, but none compared the two materials. Thirty-one patients undergoing primary microdiscectomy were randomly assigned to receive either ALG or PSM. Postoperatively, patients were evaluated by magnetic resonance imaging (MRI), with contrast, for volume and rostral–caudal extent of scar tissue and nerve root involvement. Back and leg pain and quality of life were assessed by neurologic examinations and standardized patient surveys. Findings at any reoperations were recorded. Results in the PSM (n = 18) and ALG (n = 13) groups were compared statistically. No operative or postoperative complications occurred. Two patients in each group required reoperation. MRI at 6 months showed no, mild or mild-moderate scarring in most patients, with no significant differences between the ALG and PSM groups in scar volume and extent or nerve root involvement. Neurologic examinations and patient surveys showed substantial reductions in pain over time in both groups but no significant differences between groups. PSM was easy to see and remove at reoperation. PSM and ALG are equally effective in preventing epidural scarring associated with postdiscectomy syndrome.     

Sonographic evaluation of the thenar compartment musculature.

The thenar region was studied with ultrasonography in 10 healthy volunteers. All thenar muscles could be identified and their course followed entirely. In addition, their function could be assessed by scanning during unresisted or resisted active movements. Standard approach, normal appearance, and dynamic tests for each muscle are described.