Power Injection of Contrast Media via Peripherally Inserted Central Catheters for CT

PURPOSE

To evaluate patient safety, catheter rupture rates, and computed tomography (CT) image quality when using peripherally inserted central catheters (PICCs) in vivo for the power injection of CT contrast media at standard injection rates.

MATERIALS AND METHODS

A prospective study to evaluate the safety and effectiveness of power injection of contrast media via indwelling PICCs was performed. Single-lumen and double-lumen polyurethane PICCs (5 F) were injected in vivo with contrast media for clinical CT examinations at injection rates ranging from 1 mL/sec to 4 mL/sec. Data collected included PICC rupture rate, patient complications, injection rate, peak injection pressure, PICC length, PICC age, and quality of contrast enhancement on the CT images.

RESULTS

One hundred ten power injections of PICCs for CT examinations were performed. There were 12 injections of single-lumen PICCs and 98 injections of double-lumen PICCs. The most common injection rate was 2 mL/sec, accounting for 89 of the 110 injections (81%). Two PICCs ruptured during power injection, both as a result of operator error. One of the PICCs that ruptured was clamped at the time of injection and the other one was kinked at its venous entry site. One additional PICC showed evidence of dysfunction; it ballooned without actually rupturing. No significant patient complications occurred. Contrast enhancement of the CT images was subjectively rated as average or above average in 95% of cases.

CONCLUSIONS

Contrast media can be power-injected via PICCs for routine CT examinations at a rate of 2 mL/sec, yielding satisfactory image quality without exposing patients to significant additional risk. Power injection rates greater than 2 mL/sec, as are typically used in CT angiography applications, were not fully evaluated by this study.

MDCT Angiography of the Extremities in Pediatric Patients: Initial Experience

OBJECTIVE

We studied the feasibility of extremity MDCT angiography in pediatric patients with congenital anomalies, an extremity mass, and a suspected arterial occlusion.

CONCLUSION

In pediatric patients, MDCT angiography of the extremities with a short imaging time and a low dose of contrast material is feasible and can be used as a noninvasive alternative to conventional angiography.

Current DVT imaging

Accurate diagnosis of deep venous thrombosis (DVT) is very difficult, and imaging plays a crucial role in the diagnosis or exclusion of DVT. The initial test of choice for diagnosis of acute thigh as well as upper extremity DVT is ultrasound, because of its high accuracy, relatively low cost, portability, and lack of ionizing radiation. In patients who are undergoing CT pulmonary angiography for suspected pulmonary embolism, CT venography can be performed as part of the examination, for comprehensive evaluation of the venous system in the legs, abdomen, and pelvis. MR has a problem-solving role, and conventional venography is now limited to specific scenarios including evaluation of central DVT in the upper extremities, as a prelude to intervention for thrombolysis/thrombectomy, and prior to placement of an inferior vena cava filter. This article discusses the imaging findings of DVT, and the role of these imaging examinations in the evaluation of patients with suspected DVT.

Dose reduction in skeletal and chest radiography using a large-area flat-panel detector based on amorphous silicon and thallium-doped cesium iodide: technical background, basic image quality parameters, and review of the literature

The two most frequently performed diagnostic X-ray examinations are those of the extremities and of the chest. Thus, dose reduction in the field of conventional skeletal and chest radiography is an important issue and there is a need to reduce man-made ionizing radiation. The large-area flat-panel detector based on amorphous silicon and thallium-doped cesium iodide provides a significant reduction of radiation dose in skeletal and chest radiography compared with traditional imaging systems. This article describes the technical background and basic image quality parameters of this 43 x 43-cm digital system, and summarizes the available literature (years 2000-2003) concerning dose reduction in experimental and clinical studies. Due to its high detective quantum efficiency and dynamic range compared with traditional screen-film systems, a dose reduction of up to 50% is possible without loss of image quality.

Dynamic MRI and fine needle aspiration cytology in the evaluation of soft tissue lesions

OBJECTIVE

To assess the usefulness of dynamic magnetic resonance imaging (DMRI) in the diagnosis of soft tissue tumors.

DESIGN AND PATIENTS

A DMRI series of 33 patients with soft tissue lesions was evaluated with regard to start, pattern, and progression of enhancement. Early enhancement, predominantly peripheral, and a time-signal intensity (TSI) curve characterized by a steep rise to an early peak followed by a plateau or washout, were considered signs of malignancy. The results were compared with the initial fine needle aspiration cytology (FNAC) diagnosis and the final diagnosis.

RESULTS

Twenty of 23 malignant lesions and three of 10 benign lesions exhibited at least two of the three enhancement characteristics attributed to malignancy. Using two or more DMRI features of malignancy to dichotomize the series, the sensitivity and positive predictive value of the DMRI series were 87% and, the specificity and negative predictive value were 70%. FNAC was conclusive except in two cases.

CONCLUSION

In tumor centers that rely on FNAC for preoperative diagnosis DMRI can be reserved for cytologically inconclusive cases. In centers that rely on open biopsy, DMRI may be useful as a coarse discriminator between benign and malignant lesions. However, larger series of soft tissue tumors need to be evaluated to conclusively identify the clinical role of DMRI.

Behavior of male-specific minor histocompatibility antigen in skin and limb transplantation

BACKGROUND

Although the role of male-specific minor histocompatibility antigen H-Y has been increasingly understood in both experimental and clinical organ transplantation, little has been investigated on musculoskeletal tissue transplantation. This study was performed to describe the behavior of male-specific minor histocompatibility H-Y antigen in rat skin and whole limb transplantation.

MATERIALS AND METHODS

Using three different strains of inbred rats (Lewis, F344, and Dark Agouti), 75 donor hindlimbs and eighteen skin grafts were isogenically transplanted to the sex-mismatched recipients. Recipients were observed up to 48 weeks postoperatively. Rejection was monitored by the appearance of the skin of the grafted limb and histology. Systemic microchimerism was assessed by polymerase chain reaction using Y-chromosome specific primers.

RESULTS

Skin rejection didn't occur in all limb transplant recipients and histology did not show any rejection findings in all components of the limb graft through 48 weeks. Successful functional recovery was expected. Stable and high level of chimerism (>1%) was detected in the lymphoid tissues in nontreated female recipients. Male skin grafts were rejected by Lewis and F344 female recipients within 6 weeks postoperatively. All female skin grafts survived in male recipients.

CONCLUSION

Our results suggest that H-Y antigen can induce graft rejection in rat skin graft but causes no rejection reaction in whole limb transplantation. Systemic chimerism may play an important role for acceptance of sex-mismatched limb graft.

[Spiral computed tomography in the diagnosis of limb osteomyelitis]

The results of radiation studies in 121 patients of different age (4 to 75 years) examined for limb osteomyelitis are analyzed. All the patients underwent routine X-ray study and computed tomography (CT), 26 patients had X-ray fistulography; 8, linear tomography; 10, CT fistulography; 6, scintigraphy, and 15, ultrasound study. Acute hematogenous osteomyelitis (AHO), chronic hematogenous osteomyelitis (CHO), and atypical (here Garre's sclerosing osteomyelitis and Brodie's abscess) osteomyelitis were ascertained in 10.6, 26.4, and 10.1% of cases, respectively. Posttraumatic osteomyelitis was diagnosed in almost 50% of the patients. CT defined the phase of chronic limb osteomyelitis. Spiral CT has proven to be the most effective technique for diagnosing limb osteomyelitis as compared with routine X-ray study: the accuracy of X-ray study was 81.8%, its sensitivity, 84.9%, and specificity, 60.0% and those of computed tomography were 96.7, 99.1, and 80.0%, respectively.

An audit of out of hours interventional vascular radiology

BACKGROUND

in 1996 the Royal College of Radiologists established a set of guidelines for out of hours radiology. Part of the recommendations determined that all units should regularly assess their own out of hours workload. In light of these guidelines we have audited our units interventional radiology activity.

METHODS

this was a retrospective study looking at the number of emergency angiograms and procedures performed over a 1-year period. Patients were identified from a vascular radiology database and case notes reviewed.

RESULTS

a total of 1902 patients had angiograms with 686 having further procedures. Of these, 1093 patients (57%) having 380 procedures (55%) were under the care of a consultant vascular surgeon. Of the vascular surgical patients only 17 patients (1.6%) were actually investigated out of hours (1700-0800 weekdays and at weekends). 5/17 (29%) patients received thrombolysis and 7/17 (41%) had either an angioplasty or stent. Despite being a major vascular unit only 2/17 (12%) were patients referred from outside the units own trust. Following diagnostic angiography, 13/17 (76%) of patients had an intervention performed within the first 24h.

CONCLUSION

in a unit performing a large number of angiograms only a small number of patients require out of hours emergency angiography and interventional vascular procedures. Our impression is that this is the result of a flexible and responsive in hour's service. At the present time extra-hospital referrals do not appear to generate large amounts of out of hours work. This level of out of hours activity has implications in the provision of vascular radiological services in the future.

Osseous change adjacent to soft-tissue hemangiomas of the extremities: correlation with lesion size and proximity to bone

OBJECTIVE

The purpose of this study was to describe the findings of MR imaging and radiographic changes that occur in osseous structures adjacent to soft-tissue hemangiomas of the extremities and to correlate them with patient symptomatology, the size of the hemangiomas, and their proximity to adjacent bone.

MATERIALS AND METHODS

We retrospectively reviewed the radiographs and MR images of 35 patients with soft-tissue hemangiomas of the extremities. The pattern and extent of the osseous change were categorized as periosteal, cortical, or medullary. Symptomatology, size, and proximity of the hemangioma to the adjacent bone were compared with the presence or absence of osseous change. Statistical analysis was performed using the Student's t test.

RESULTS

Osseous change was noted on radiographs in 13 (37%) of 35 patients and on MR images in 11 (31%) of 35 patients with a total of 14 patients (40%) showing osseous change on at least one study. Periosteal change was present in eight (23%) of 35 patients; cortical change, in 11 (31%) of 35 patients; and medullary change, in 10 (29%) of 35 patients. Direct contact between the soft-tissue hemangioma and the adjacent bone was seen in 13 of 14 patients with osseous change. In those patients without osseous change, the average distance between the soft-tissue hemangioma and bone was 1.06 cm (range, 0-4 cm). No correlation was found between symptoms and the presence of osseous change.

CONCLUSION

Soft-tissue hemangiomas of the extremities frequently result in adjacent osseous change that can be categorized as either periosteal, cortical, or medullary. Only medullary changes correspond with hemangioma size, whereas all three categories of change correlate with the proximity of the hemangioma to the adjacent bone. The presence of osseous change does not correlate with patient symptomatology.

[Value of roentgen diagnosis in recognition of primary and potentially malignant bone tumors]

To assess the efficiency of plain radiographs for the detection of primary and potentially malignant bone tumors a retrospective study in 70 patients with histologically proven bone sarcomas was performed. Plain radiographs were the first imaging modality in most cases and for many patients the basic step leading to further diagnostic investigations. With young patients suffering from bone pain imaging work-up was obtained immediately, whereas older patients showed significant delay until radiographs were performed. The findings of this study suggest that radiography is an effective tool for the diagnosis of primary and potentially malignant bone tumors and that physicians should think of bone tumors also when patients beyond the adolescence have focal bone pain.

X-ray refraction effects: application to the imaging of biological tissues

The purpose of this study was to explore the potential of refraction contrast X-ray imaging of biological tissues. Images of dissected mouse lungs, heart, liver and legs were produced using the medical beamline at the Elettra Synchrotron at Trieste, Italy. The technique used was diffraction enhanced imaging. This utilizes a silicon crystal positioned between the tissue sample and the detector to separate refracted X-rays from transmitted and scattered radiation by Bragg diffraction. The contrast in the images produced is related to changes in the X-ray refractive index of the tissues, resulting in remarkable clarity compared with conventional X-ray images based on absorption effects. These changes were greatest at the boundaries between different tissues, giving a marked edge enhancement effect and three-dimensional appearance to the images. The technique provides a way of imaging a property of biological tissues not yet exploited, and further studies are planned to identify specific applications in medical imaging.

[Prenatal ultrasonographic evaluation of fetal limbs anatomy and fetal limbs malformations using a systematic continuous sequence approach]

OBJECTIVE

To review the value of ultrasonographic evaluation on fetal limbs anatomy and malformations in prenatal diagnosis using a systematic continuous sequence approach (SCSA).

METHODS

Successive 4,932 prenatal ultrasonographic evaluation during gestation aging 14 - 40 weeks from August 2000 to September 2002 entered the present review. SCSA was applied to scan each limb of the fetus respectively.

RESULTS

The anatomic structures of the four limbs of the fetus were clearly displayed and correctly recognized on ultrasonic images using the SCSA in 4 750 cases (96.3%). Ninety eight limb malformations of 34 fetuses were correctly diagnosed (87.2%). Whereas 16 malformations of 5 fetuses were missed to recognize (12.8%). The diagnoses were confirmed after subsequent labor or induced labor. The sensitivity, specificity, accuracy, positive and negative predictive values were 87.2%, 99.8%, 99.2%, 81.0% and 99.9%, respectively.

CONCLUSION

The majority of fetal limb structures and malformations can be clearly demonstrated on prenatal ultrasonic imaging using SCSA. SCSA for prenatal ultrasonographic evaluation of the fetal limbs is a reliable and accurate diagnostic modality so far as the skills become more sophisticated.

Technetium-99m tetrofosmin scintigraphy in pediatric osteogenic sarcoma

Technetium-99m tetrofosmin (TF) is a myocardial perfusion agent that has recently proved useful also as tumor-seeking tracer. The aim of this study was to make a preliminary assessment of TF scintigraphy in osteosarcoma, with regard to tumor detection and monitoring of response to preoperative chemotherapy (PC). Current clinical investigations have demonstrated that the curability of osteogenic sarcoma mainly depends on the response to PC, and the percentage of tumor necrosis is the most powerful prognostic factor. However, this is difficult to assess radiologically, and it can only been obtained by histologic examination after surgery. Fourteen patients (7 males, age range: 1-17 years) with recently discovered osteosarcoma of the extremities or the pelvis were injected with TF ( approximately 7.4 MBq/kg i.v., never in the affected limb): a dynamic acquisition (20 min) was performed immediately post-injection, followed by static planar views of the involved area. Six patients were studied twice: before and after PC. Images were evaluated visually and quantitatively using regions of interest over lesion (L) and controlateral normal tissue (N). All initial TF scans demonstrated very rapid tumoral uptake (1-2 min post-injection); the mean L/N ratio at 20 min was 2.76+/-1.05. The post-PC scans showed reduced uptake in 4 patients, unchanged in one and increased accumulation in one case, with a strong correlation between the percentage change in L/N and the percentage of tumor necrosis. Our preliminary data indicate that TF is able to detect osteosarcoma; further studies including larger population is need to confirm its usefulness in non-invasively predicting response to PC.

Value of fetal skeletal radiographs in the diagnosis of fetal death

The aim of this study was to assess the value of fetal skeletal radiographs in determining the etiology of fetal death. A total of 1193 post-mortem fetal skeletal radiographs were analysed. Fetuses were classified into one of three groups (group I: abnormality diagnosed during pregnancy; group II: maternal pathology; group III: spontaneous abortion of pregnancy, IIIa before 26 weeks of gestation (WG), IIIb after 26 weeks of gestation). Face, supine and lateral skeletal views were performed. Skeletal abnormalities were detected in 33.9% of the fetuses, including 22.7% with minor abnormalities (abnormal rib number, no nasal bone ossification, amesophalangia or P2 hypoplasia of the fifth digit) and 14.5% with major abnormalities (other skeletal abnormalities). Among the fetuses with major abnormalities, 98.8% came from group I, 2.9% came from group II, 2.3% came from group IIIa and none came from group IIIb. Fetal skeletal radiographs are not useful in fetuses arising from spontaneous abortion of pregnancy without abnormality on ultrasound screening, abnormality clinical examination or in fetuses with prenatal diagnosis of chromosomal abnormality. This practice is valuable only if there is a multidisciplinary team, with all the participants (pathologists, radiologists, geneticists) knowledgeable about fetal pathology. In the absence of this multidisciplinary approach, it is easier to X-ray all fetuses to avoid misdiagnosis and the important consequences for genetic counselling.

A rare case of infantile Ollier's disease demonstrating bilaterally symmetric extremity involvement

We report an unusual case of Ollier's disease presenting at an atypically early age and with extensive, bilaterally symmetric features.

99mTc-MIBI in the assessment of response to chemotherapy and detection of recurrences in bone and soft tissue tumours of the extremities

AIM

This prospective study is focused on the assessment of tumour response in a group of 28 bone sarcoma patients using (99m)Tc-MIBI scintigraphy.

METHODS

The quantitative changes in MIBI uptake before and after chemotherapy were measured and associated with the pathological evaluation of the degree of tumour necrosis. Besides this, another group of 40 patients with bone and soft tissue tumours was studied in order to evaluate the diagnostic efficacy of (99m)Tc-MIBI scintigraphy versus computed tomography (CT) and/or magnetic resonance imaging (MRI) in detecting the status of the disease and its recurrences. After injection of 555-740 MBq of (99m)Tc-MIBI, regional and whole body images were acquired at 20 and 60 min. The lesion/normal (L/N) uptake ratio was calculated in both early and delayed images and the washout rate (WR%) of (99m)Tc-MIBI was obtained. Following 3-4 courses of chemotherapy, bone tumours were assessed by comparing the uptake ratio in the viable tumours with the amount of necrotic processes described in the surgically removed specimens.

RESULTS

In the first group of patients the rate of tumour response to chemotherapy, calculated according to the percentage of necrosis and the (99m)Tc-MIBI uptake ratios, was as follows: complete response in 12 patients, partial response in 8 and no response in 8 patients. Linear regression analysis of quantitative changes in (99m)Tc-MIBI uptake (expressed as changes percent) and of (99m)Tc-MIBI uptake ratio showed a positive correlation (r=0.77), whereas it showed a negative correlation with the changes in the washout ratio (r=-0.32). In the second group of patients (40 patients) (99m)Tc-MIBI scintigraphy proved to be able to detect recurrences of bone and soft tissue tumours. The sensitivity, specificity and accuracy of (99m)Tc-MIBI scan versus CT and/or MRI were calculated and they resulted 93%, 95% and 92% versus 86%, 75% and 84%, respectively.

CONCLUSION

The application of (99m)Tc-MIBI scan in the management of patients treated with chemotherapy may allow an early identification of the non-responder patients and lead to a choice of different strategies (alternative chemotherapy or salvage surgery).

Evaluation of hemangioma by positron emission tomography: role in a multimodality approach

PURPOSE

The relative utility of various preoperative diagnostic imaging modalities for the evaluation of hemangioma of the extremities, including positron emission tomography (PET) (using 18F-fluoro-2-deoxy-D-glucose [FDG] and fluorine-18 alpha-methyltyrosine [FMT]), computed tomography (CT), magnetic resonance imaging (MRI), and digital subtraction angiography (DSA), was investigated.

METHODS

Imaging findings in 16 patients with 16 histopathologically documented hemangiomas of the extremities were retrospectively reviewed. Preoperative imaging included: FDG-PET (n = 16), FMT-PET (n = 12), MRI (n =16), CT (n =11), and DSA (n =14).

RESULTS

All 16 lesions examined by PET with FDG and/or FMT showed accumulation. The standardized uptake values (SUVs) for FDG-PET for the 16 examined tumors ranged from 0.7 to 1.67; for FMT-PET, they ranged from 0.14 to 1.00. The SUVs with both tracers indicated the benign nature of the tumor. Computed tomography demonstrated variable attenuation and phleboliths in two patients. The MRI signal characteristics were relatively consistent: heterogeneous signals were slightly higher than those of skeletal muscle on T1-weighted images and brighter than those of subcutaneous fat on T2-weighted images. The pooling and cotton-wool staining depicted in DSA was found to be significantly correlated with FDG accumulation, suggesting that localized blood retention-induced ischemia may accelerate anaerobic glycolysis, which leads to high FDG uptake.

CONCLUSION

Although plain radiography, CT, MRI, and angiography may provide anatomic extent and be pathognomonic, FDG-PET and FMT-PET may be the most reliable among the studied imaging modalities for differentiating benign hemangiomas from other soft tissue tumors, especially malignant neoplasms.

Thyroid acropachy: report of 40 patients treated at a single institution in a 26-year period

Thyroid acropachy is an extreme manifestation of autoimmune thyroid disease. It presents with digital clubbing, swelling of digits and toes, and periosteal reaction of extremity bones. It is almost always associated with ophthalmopathy and thyroid dermopathy. During a 26-yr period at our institution, of 178 patients with thyroid dermopathy, 40 had acropachy. Clubbing associated with thyroid dermopathy (pretibial myxedema) was seen in 35 patients. Clubbing usually was not a patient complaint and was noted only by clinical observers. Four of eight patients with hand and extremity radiographs had periosteal reaction. Seven had associated extremity and joint pain; this pain was absent at long-term follow-up. Half of the patients required systemic corticosteroid therapy, 53% required transantral or transfrontal orbital decompression for severe ophthalmopathy, and 18% had the elephantiasic form of dermopathy. Cigarette-smoking rates were 81% for women and 75% for men (mean, 28 pack-years). All 13 patients who had thyroid-stimulating Ig measurement had high titers. Long-term follow-up (median, 12.5 yr) revealed that acropachy was not a complaint in follow-up visits or questionnaires. The data suggest that thyroid acropachy is an indicator of severity of ophthalmopathy and dermopathy. It is a source of clinical concern only if dermopathy is persistent and severe.

[Spiral computed tomography in the diagnosis of limb osteomyelitis]

The results of radiation studies in 121 patients of different age (4 to 75 years) examined for limb osteomyelitis are analyzed. All the patients underwent routine X-ray study and computed tomography (CT), 26 patients had X-ray fistulography; 8, linear tomography; 10, CT fistulography; 6, scintigraphy, and 15, ultrasound study. Acute hematogenous osteomyelitis (AHO), chronic hematogenous osteomyelitis (CHO), and atypical (here Garre's sclerosing osteomyelitis and Brodie's abscess) osteomyelitis were ascertained in 10.6, 26.4, and 10.1% of cases, respectively. Posttraumatic osteomyelitis was diagnosed in almost 50% of the patients. CT defined the phase of chronic limb osteomyelitis. Spiral CT has proven to be the most effective technique for diagnosing limb osteomyelitis as compared with routine X-ray study: the accuracy of X-ray study was 81.8%, its sensitivity, 84.9%, and specificity, 60.0% and those of computed tomography were 96.7, 99.1, and 80.0%, respectively.

Multiple congenital contractures (congenital multiple arthrogryposis)

Arthrogryposis, is the occurrence of joint contractures of variable etiology that start prenatally. Arthrogryposis may result from neurologic deficit, neuromuscular disorders, connective tissue abnormalities, amniotic bands, [figure: see text] or fetal crowding. Arthrogryposis may result from no apparent hereditary causes (neuropathic, for example) or may be the result of hereditary factors (myopathic form, for example). Ultrasound diagnosis depends on observation of scant or absent motion of fetal extremities. Prognosis depends on the specific etiology of the contractures.

Prenatal diagnosis: what does four-dimensional ultrasound add?

INTRODUCTION

The key benefit of 4D ultrasound lies in providing real-time 3D images of embryonic or fetal movements, previously limited by technological advancement.

AIM

To classify types of first trimester embryonic and fetal movements in normal pregnancies as seen by 4D sonography.

RESULTS

Three types of movements can be visualized in the first trimester: gross body between seven and eight weeks, limb movements after ten weeks and complex limb movements after 11 weeks of gestation.

DISCUSSION

An alteration from the given pattern of motoric development should be considered as an indication for further investigation.

CONCLUSION

4D ultrasound enables visualization of more details of the dynamics of small anatomical structures. Therefore, body and limb movements can be visualized a week earlier than with 2D.

Blunt trauma in the obstetric patient: monitoring practices in the ED

This study was undertaken to determine the usually used approach to fetal monitoring in the emergency department (ED) of the less severely injured obstetric patient who has sustained blunt trauma. A written survey was sent to clinical directors of teaching programs in emergency medicine (EM) with inquiries on the usual way of monitoring, what studies were performed, and the usual disposition of the less-injured obstetric patient. From the 112 teaching programs surveyed in early 1996, there were 87 responses (78%). Seventy-eight percent of programs generally have fetal monitoring performed for 2 to 4 hours in obstetric trauma patients when the trauma is more than minor extremity injury. In 68%, fetal monitoring was not performed in the ED from the time of the initial assessment of fetal heart tones until the mother went to an obstetric area even though the average estimated time to radiographically clear a cervical spine was 36 minutes. In 92% of programs residents are taught cardiotocographic changes indicative of fetal distress but only 15% have such monitoring equipment in their department. However, 51% do have sonographic equipment in their department. Given a patient with a viable fetus who has no abdominal pain, 46% routinely use fetal monitoring if the mechanism is a simple fall whereas 92% use monitoring only if the mechanism is a rollover motor vehicle collision or a strike to the abdomen. It is generally recognized that fetal distress may occur subtly without overt clinical signs and that obstetric area monitoring for a period of several hours should take place. However, most teaching programs do not institute continuous fetal monitoring during the first 30 to 60 minutes that the mother is undergoing her work-up even though residents are taught such monitoring.

Automated hands-free image manipulation and viewing: a useful macro feature that assists radiologists in the viewing of chest and extremity digital radiographs

The authors present an adaptation of the macro recording feature on the Siemens Magic View 1000 workstation, which, with the click of one button, launches a macro that performs 3 clinically useful image manipulations. Using a Magic View 1004 Siemens unix workstation, the following Macro sequence was programmed: (1) select all images, (2) reverse grayscale, (3) edge enhancement, (4) display full-resolution all screens, (5) reverse grayscale, (6) enable zoom/pan function. This sequence of commands takes 11 seconds to complete for a 2-view chest x-ray, and 16 seconds for a 3-view hand series. A pause occurs while the CPU performs the edge enhancement algorithm; this "pause" is used to provide time for the radiologist to assess the images. The time to implement and view these manipulations is reduced dramatically with the automatic viewing macro. More importantly, because the macro takes over the workstation operation, radiologist attention can be focused totally on image assessment and interpretation. Automatic hands-free image manipulation can improve the speed and accuracy of radiologist interpretation for both chest and extremity digital radiography.

Achondrogenesis type II with normally developed extremities: a case report

We present a case of achondrogenesis type II with normally developed extremities that was confirmed with postmortem ultrasonographic and radiographic examination. The length of the long bones may vary and the diagnosis of achondrogenesis should not be ruled out with normally developed extremities. Intrauterine sonographic examination of the vertebrae is very important and the absence of vertebral body ossification may be the unique finding of achondrogenesis type II. Axial ultrasonographic images and postmortem plain radiographs are useful to clarify the pathology.

Clinical evaluation of digital radiography based on a large-area cesium iodide-amorphous silicon flat-panel detector compared with screen-film radiography for skeletal system and abdomen

The aim of this clinical study was to compare the image quality of digital radiography using the new digital Bucky system based on a flat-panel detector with that of a conventional screen-film system for the skeletal structure and the abdomen. Fifty patients were examined using digital radiography with a flat-panel detector and screen-film systems, 25 for the skeletal structures and 25 for the abdomen. Six radiologists judged each paired image acquired under the same exposure parameters concerning three observation items for the bone and six items for the abdomen. Digital radiographic images for the bone were evaluated to be similar to screen-film images at the mean of 42.2%, to be superior at 50.2%, and to be inferior at 7.6%. Digital radiographic images for the abdomen were judged to be similar to screen-film images at the mean of 43.4%, superior at 52.4%, and inferior at 4.2%; thus, digital radiographic images were estimated to be either similar as or superior to screen-film images at over 92% for the bone and abdomen. On the statistical analysis, digital radiographic images were also judged to be preferred significantly in the most items for the bone and abdomen. In conclusion, the image quality of digital radiography with a flat-panel detector was superior to that of a screen-film system under the same exposure parameters, suggesting that dose reduction is possible with digital radiography.

Qualitative and quantitative comparison between images obtained with filtered back projection and iterative reconstruction in prostate cancer lesions of (18)F-FDG PET

BACKGROUND

Recently, iterative reconstruction with segmented attenuation corrections (IRSAC) has been introduced for reconstruction of (18)F-FDG PET images. IRSAC produces images that are more pleasing to the eye, but qualitative and quantitative comparisons between IRSAC and filtered back projection (FBP) have not been reported for metastatic cancer. Since quantitative data has been widely used as an adjunct to interpretation of PET scans, comparison between IRSAC and FBP is needed. The purpose of this study was to compare image quality and the maximum standardized uptake value (SUVmax) obtained with FBP and with IRSAC in metastatic lesions from prostate cancer.

METHODS

Twenty (18)F-FDG PET scans (10 baseline and 10 follow-up) were performed in 10 patients with prostate cancer (ages 66-85 yrs, mean 73.6 yrs). Acquisition began 45 min after injection of 370 MBq of (18)F-FDG. Images were reconstructed using FBP and IRSAC, and submitted to visual and quantitative analysis. SUVmax was obtained for all metastases, on FBP and IRSAC. A Jaszczak phantom study was also performed.

RESULTS

IRSAC images showed better image quality than FBP especially in regions of high activity concentrations. IRSAC detected 106 lesions on both baseline and follow-up scans, while FBP detected 100 and 95 lesions on baseline and follow-up scans, respectively. Therefore, 17 more lesions were seen on IRSAC. The mean SUVmax values on baseline scans for FBP and IRSAC were systematically different, at 4.46+/-1.99 and 5.13+/-2.67, respectively. On follow-up scans values were 3.89+/-1.72 for FBP and 4.29+/-1.93 for IRSAC. Comparison of FBP with IRSAC on baseline and follow-up scans were statistically significant (baseline: paired "t"-test p=0.0017; follow-up: paired "t"-test p=0.0008). Phantom studies reveal that these differences can be explained by the type of reconstruction filters used, and IRSAC was more accurate than FBP.

CONCLUSIONS

IRSAC detects smaller volumes in phantoms, patient images are easier to interpret and more metastatic lesions were detected. In addition, IRSAC provides reproducible quantitative data, comparable to data provided by FBP. IRSAC SUV and FBP SUV are in close agreement but there was a statistically significant difference between the two, and therefore threshold values of SUV will probably need to be re-determined with IRSAC, and are likely to be 10 to 19% higher than currently reported.

Imaging body armor

This study examined the feasibility of performing radiographic studies on patients wearing standard-issue body armor. The Kevlar helmet, fragmentation vest, demining suit sleeve, and armor plate were studied with plain film and computed tomography in a simulated casualty situation. We found that the military helmet contains metal screws and metal clips in the headband, but diagnostic computed tomographic images can be obtained. Kevlar, the principal component of soft armor, has favorable photon attenuation characteristics. Plate armor of composite material also did not limit radiographic studies. Therefore, when medically advantageous, patients can be examined radiographically while wearing standard military body armor. Civilian emergency rooms should be aware of these observations because law enforcement officers wear similar protective armor.

Success of thrombolysis as a predictor of outcome in acute thrombosis of popliteal aneurysms

PURPOSE

Acute limb ischemia after thrombosis of a popliteal aneurysm is a distinct and limb-threatening entity. Preoperative intra-arterial thrombolysis may improve the outcome in this challenging situation. This study retrospectively analyzed a consecutive series of patients treated with preoperative thrombolysis and subsequent revascularization.

METHODS

Thirteen patients with acute limb ischemia caused by thrombosis of a popliteal aneurysm underwent catheter-directed intra-arterial thrombolysis with urokinase and subsequent vascular reconstruction. The angiographic and clinical outcome was analyzed and compared with that in the literature.

RESULTS

Complete aneurysm thrombosis with absence of runoff was documented in 12 cases. Thrombolysis restored perfusion with patency of the popliteal artery and a one- or two-vessel runoff in 77% of cases (10/13). Early cumulative graft patency and limb salvage rates were 68% and 83%, respectively, with an ankle/brachial index of 0.8 +/- 0.2. Lytic failure followed by attempts at bypass grafting was present in three patients (23%) and resulted in above-knee amputation. Severe rhabdomyolysis and fatal pulmonary embolism were responsible for a 15% early mortality rate.

CONCLUSION

Preoperative thrombolysis followed by bypass grafting is a valid treatment option for patients who can withstand an additional period of ischemia that does not require immediate revascularization and intraoperative lysis. Lytic failure identifies patients with a highly compromised runoff who are probably best treated by means of subsequent amputation, without any attempts at bypass grafting.

Angiographic scoring of vascular occlusive disease in the diabetic foot: relevance to bypass graft patency and limb salvage

OBJECTIVE

We graded the severity of occlusive disease in foot vessels of patients with diabetes and correlated the scoring obtained with graft patency and limb salvage.

METHODS

In this retrospective review of 199 limbs studied by means of angiography in 117 patients with diabetes mellitus, 124 limbs underwent bypass grafting. Each dorsalis pedis (DP), lateral plantar (LP), and medial plantar (MP) artery was assigned a score according to the reporting standards of the Joint Vascular Societies Council (0, no stenosis > 20%; 1, 21%-49% stenosis; 2, 50%-99% stenosis; 2.5, < half the vessel length occluded; 3, > half the vessel length occluded.) A foot score (DP + MP + LP + 1) was calculated for each foot (1 to 10). The mean follow-up period was 14 months.

RESULTS

For all 199 limbs and for the 124 limbs that underwent bypass grafting, the mean scores were similar for the DP, MP, and LP (1.8 +/- 1.0, 1.9 +/- 1.0, 1.9 +/- 1.0, respectively; P >.4). Only the MP and LP correlated with each other (r = 0.57; P <.0001). There were no scoring differences between limbs with symptoms and limbs that did not undergo bypass grafting. Bypass graft patency correlated with both the foot score and the MP score for tibial and inframalleolar grafts (P <.04). Patency correlated with the LP score only for inframalleolar bypass grafting procedures. The DP score alone did not differ between bypass grafts that remained patent and bypass grafts that failed. Bypass grafts in limbs with a foot score less than 7 and an MP score less than 2 had only a 2% failure rate. A foot score greater or equal to 7 was associated with a 30% failure rate for all bypass grafts (41% for inframalleolar grafts). Bypass grafts with low foot scores that failed did so much later than bypass grafts with high foot scores that failed (17 +/- 11 months vs 6 +/- 8 months; P <.02), possibly reflecting different etiologies for the failure. The limb salvage rate correlated with foot score (P <.05). The limbs that were saved had an average foot score of 6.4 +/- 2.0, versus 7.2 +/- 1.4 for limbs that required amputation.

CONCLUSION

In patients with diabetes mellitus, the foot score is a useful tool for predicting the likelihood of graft patency and limb salvage for infrapopliteal revascularization. However, the relatively high bypass success rate (70%) in the presence of a high foot score (>or= 7) does not allow its use in identifying the subgroup of patients who are unlikely to benefit from bypass grafting surgery. It cannot be used as a means of selecting patients for primary amputation.

Wooden foreign bodies: imaging appearance

OBJECTIVE

The purpose of this study was to identify the characteristic imaging features of wooden foreign bodies.

MATERIALS AND METHODS

The imaging studies of 12 patients with surgically confirmed wooden foreign bodies were retrospectively reviewed. The study group consisted of seven females and five males, 10-65 years old (mean age, 36 years). All patients underwent radiography. Nine patients were evaluated with sonography, eight with MR imaging, three with CT, and one with CT arthrography. Gadolinium-enhanced MR imaging was performed in six patients. Three patients presented with a draining sinus and nine with painful swelling. Only three patients presented with a history of penetrating injury.

RESULTS

Lesions were located in the foot (n = 4), hand (n = 3), thigh (n = 2), calf (n = 2), and elbow (n = 1). Radiographs failed to reveal the retained foreign bodies in all patients. With MR imaging, wooden foreign bodies displayed a variable signal intensity that was equal to or less than that of skeletal muscle on both T1- and T2-weighted images. MR imaging showed the surrounding inflammatory response in all patients. CT showed the retained wood as linear cylindric foci of increased attenuation. Wood was highly echogenic and revealed pronounced acoustic shadowing on sonography. Arthrography in one patient showed an associated reactive synovitis.

CONCLUSION

The imaging appearance of wooden foreign bodies is variable; however, imaging can be quite specific, and when taken in the appropriate clinical setting, the imaging should reliably suggest the diagnosis. Sonography is frequently underused but proved most useful for the evaluation of retained wooden foreign bodies.

[Surgical strategies and choice of treatment methods of the sequelae of the main vessels damage in extremities]

The data on diagnosis, surgical tactics and method of treatment of 75 patients with consequences of the extremities main vessels damage were presented. In 18 patients pulsating hematoma have occurred, in 16--the arterial one, in 12--arteriovenous aneurysm, in 29--the disease of ligated vessel. The data on clinical investigations, ultrasonic dopplerography and roentgencontrast angiography were used for the diagnosis. There were operated on 66 patients. Restorational operation on vessels was done in 47 (71.2%), of them ligation of the vessels--in 16 (24.2%), the lumbar sympathectomy--in 3 (4.5%). The immediate positive result of the treatment was noted in 63 (95.5%) of patients. All the patients are alive. Original method of traumatic aneurysm treatment was adduced.

Intravascular ultrasound scanning improves long-term patency of iliac lesions treated with balloon angioplasty and primary stenting

PURPOSE

Underdeployment of an intravascular stent has been identified as a cause of restenosis or occlusion of a treated arterial lesion. Intravascular ultrasound (IVUS) has been shown to initially improve the anatomic and clinical stenting. The purpose of this study was to determine whether the use of IVUS increased long-term patency of this intervention.

METHODS

Between March 1992 and October 1995, 71 limbs (52 patients) with symptomatic aortoiliac occlusive disease underwent balloon angioplasty with primary stenting. IVUS and arteriography were used in 49 limbs (36 patients) to evaluate stent deployment. Arteriography alone was used in 22 limbs (16 patients) to evaluate stent deployment. Patients were captured prospectively in a vascular registry and retrospectively reviewed.

RESULTS

Mean age of patients treated with IVUS was 61.1 plus minus 9.0 years (range, 38-85) versus 70.0 plus minus 10.1 years (range, 57-87) in patients treated without IVUS (P <.01). There was no difference between the groups with respect to preoperative comorbidities, ankle-brachial indices, or number of stents per limb. Mean follow-up for IVUS patients was 62.1 plus minus 7.3 months (range, 15-81) and 57.9 plus minus 8.7 months (range, 8-80) for patients treated without IVUS (P = not significant). In 40% (20/49) of limbs, IVUS demonstrated inadequate stent deployment at the time of the original procedure. Kaplan-Meier 3- and 6-year primary patency estimates were 100% and 100% in the IVUS group and 82% and 69%, respectively, in limbs treated without IVUS (P <.001). There have been no secondary procedures performed in limbs treated with IVUS and a 23% (5/22) secondary intervention rate in the non-IVUS group (P <.05). Overall Kaplan-Meier survival estimates at 3 and 6 years for all patients were 84% and 67%, respectively.

CONCLUSION

Balloon angioplasty and primary stenting of symptomatic aortoiliac occlusive lesions is a durable treatment option. Long-term follow-up of treated patients shows outcomes that are comparable with direct surgical intervention. IVUS significantly improved the long-term patency of iliac arterial lesions treated with balloon angioplasty and stenting by defining the appropriate angioplasty diameter endpoint and adequacy of stent deployment.

The Minnesota Regional Peripheral Arterial Disease Screening Program: toward a definition of community standards of care

The Minnesota Regional Peripheral Arterial Disease Screening Program was designed to define the efficacy of community PAD detection efforts, to assess the disease-specific and health-related morbidity, to assess PAD awareness rates, and to determine the magnitude of atherosclerosis disease risk factors and the intensity of their management. The target population was recruited via mass media efforts directed at individuals over 50 years of age and those with leg pain with ambulation. Screening sessions included assessments of the ankle-brachial index, blood pressure, fasting lipid profile, and use of validated tools to detect symptomatic claudication (by the Modified WHO-Edinburgh Claudication Questionnaire), walking impairment (Walking Impairment Questionnaire - WIQ), quality of life (MOS SF-36), PAD awareness, and the intensity of PAD medical therapeutic interventions. PAD was defined as any ankle-brachial index < or =0.85 or a history of lower extremity revascularization. The program evaluated 347 individuals and identified 92 subjects with PAD and 255 subjects without PAD, yielding a detection rate of 26.5%. Individuals with PAD were older, tended to have higher blood pressures, and had a significant walking impairment and an impaired health-related quality of life compared with the non-PAD subjects. Current rates of tobacco use were low. Lipid-lowering, estrogen replacement, anti-platelet, and antihypertensive medications and exercise therapies were underutilized in the PAD cohort. Peripheral arterial disease awareness was low in these community-identified patients. This Program demonstrated that individuals with PAD can be efficiently identified within the community, but that current standards of medical care are low. These data can assist in the future development of PAD awareness, education, and treatment programs.

Regional blood flow in sea turtles: implications for heat exchange in an aquatic ectotherm

Despite substantial knowledge on thermoregulation in reptiles, the mechanisms involved in heat exchange of sea turtles have not been investigated in detail. We studied blood flow in the front flippers of two green turtles, Chelonia mydas, and four loggerhead turtles, Caretta caretta, using Doppler ultrasound to assess the importance of regional blood flow in temperature regulation. Mean blood flow velocity and heart rate were determined for the water temperature at which the turtles were acclimated (19.3 degrees-22.5 degrees C) and for several experimental water temperatures (17 degrees-32 degrees C) to which the turtles were exposed for a short time. Flipper circulation increased with increasing water temperature, whereas during cooling, flipper circulation was greatly reduced. Heart rate was also positively correlated with water temperature; however, there were large variations between individual heart rate responses. Body temperatures, which were additionally determined for the two green turtles and six loggerhead turtles, increased faster during heating than during cooling. Heating rates were positively correlated with the difference between acclimation and experimental temperature and negatively correlated with body mass. Our data suggest that by varying circulation of the front flippers, turtles are capable of either transporting heat quickly into the body or retaining heat inside the body, depending on the prevailing thermal demands.

Imaging of malignant infantile osteopetrosis before and after bone marrow transplantation

BACKGROUND

Malignant infantile osteopetrosis (MIOP) is a sclerosing bone disease caused by absence or defective function of osteoclasts. Since these are of haemopoietic origin, the disease can be cured by allogeneic stem-cell transplantation, but there are no detailed studies of radiological follow-up of these procedures.

OBJECTIVE

To investigate the radiological findings at presentation and follow-up in children undergoing bone marrow transplantation (BMT) for MIOP.

MATERIALS AND METHODS

Examination of the records and imaging studies of nine paediatric patients undergoing BMT for MIOP during 1988-2000.

RESULTS

Presentation findings included characteristic features such as fractures, subperiosteal new bone formation and rachitic appearances. Five children engrafted successfully, allowing assessment of the nature and speed of resolution of radiological features after transplantation.

CONCLUSIONS

Radiological improvement was apparent within 2 months of successful engraftment with almost complete resolution of abnormalities after 1 year. Studies in two children who are, respectively, 58 and 83 months post-transplant show complete resolution of all bone changes.

Factors influencing blood flow in the equine digit and their effect on uptake of 99m technetium methylene diphosphonate into bone

It was hypothesised that exercise may promote perfusion of the distal part of the limbs and enhance uptake of radiopharmaceutical into bone, but bandaging and lameness would have no effect. Two hundred and two horses undergoing routine nuclear scintigraphic examination for assessment of lameness or poor performance between November 1998 and November 1999 were assigned randomly to one of 4 groups: no bandages and no exercise (NB/NE); bandages and no exercise (B/NE); no bandages and exercise (NB/E); bandages and exercise (B/E). In the bandage groups, the distal forelimbs were bandaged for at least 16 h prior to injection of radiopharmaceutical. In the exercise groups, horses were lunged for 15 min at trot and canter prior to injection. Quantitative values for perfusion of the front feet and uptake of the radiopharmaceutical into the bones of the distal limb were obtained from scintigraphic measurements during the vascular and bone phases of radiopharmaceutical distribution. Perfusion of the front feet was classified as good in 60% of limbs, reduced in 21% and poor in 19%. There was a strong positive relationship between exercise and both perfusion of the front feet and uptake of the radiopharmaceutical into bone. Bandaging had no effect. There was a relationship between environmental temperature and both perfusion and uptake of the radiopharmaceutical into bone. Estimation of foot surface temperature using thermography was helpful in predicting perfusion of the distal limbs. There was no relationship between lameness and uptake of the radiopharmaceutical into bone. It is therefore recommended that, whenever possible, horses are exercised for 15 min prior to injection of radiopharmaceutical if nuclear scintigraphy of the distal parts of the limb is to be performed.

The cost-effectiveness of exclusion arteriography in extremity trauma

The purpose of this study was to apply decision analysis to an established practice in vascular trauma diagnosis. While exclusion arteriography has resulted in an increase in positive surgical explorations, no formal analysis that determined either the cost-effectiveness of exclusion arteriography or the cost-effectiveness ratio has been reported in the literature. We created a decision model that compared exclusion arteriography and surgical exploration, the standard used prior to the development of extremity arteriography. The decision model used predominantly literature derived estimates for the prevalence of arterial injuries and the accuracy, complications, outcomes and costs of both arteriography and exploration. Exclusion arteriography is cost-effective. This finding is robust to changes in the major model variables. Compared to surgical exploration, exclusion arteriography is a superior strategy by dominance (more effective and costs less). Therefore, a cost-effectiveness ratio cannot be calculated. Under the base case assumption of 28% prevalence of arterial injury requiring operation, exclusion arteriography saves about $2000 and adds 0.3 quality adjusted life years (QALY) for each patient. Decision analysis can be successfully applied to problems in vascular trauma diagnosis.

Contrast-enhanced three-dimensional helical CT for soft tissue tumors in the extremities

OBJECTIVE

To evaluate the ability of contrast-enhanced three-dimensional (3D) helical computed tomography (CT) to image soft tissue tumors in the extremities.

DESIGN AND PATIENTS

Forty-five consecutive patients with soft tissue tumors in the extremities were examined (mean age 46.2 years; 24 females, 21 males). Twenty-five patients had benign lesions and 20 had malignant lesions. All the patients underwent contrast-enhanced 3DCT scanning and magnetic resonance (MR) imaging preoperatively. All patients were surgically treated. Spiral CT scanning was performed with intravenous contrast enhancement. 3D reconstruction images were produced after thresholding, using Active-Windows (version 2.0, General Electric, Milwaukee, WI) software. 3DCT findings were compared in a masked fashion with the MR imaging and surgical findings regarding bone and major vessel invasion by the tumors.

RESULTS

Forty-four of 45 tumors were satisfactorily imaged for the interpretation of their size, location and relationship to the skeleton and major vessels. One malignant tumor was judged on 3DCT to invade the major vessel, but the vessel proved to be normal at surgery.

CONCLUSIONS

Contrast-enhanced 3D helical CT can be used for the evaluation of soft tissue tumors in the extremities, for preoperative surgical planning.

Correlation of Tc-99m-red blood cell phleboscintigraphy with clinical severity of chronic venous disease

Equilibrium red blood cell phleboscintigraphy of the lower limbs for the diagnostic management of chronic venous disease has been proposed. The aim of this study was to verify the correlation of the phleboscintigraphic assessment of chronic venous disease with the clinical grading of the severity of the disease, since other diagnostic modalities have been recently demonstrated a poor and only partial correlation. Equilibrium Tc-99m-red blood cell phleboscintigraphy was performed in 27 patients with chronic venous disease. Scintigraphic images of 52 limbs were classified according to a four-class qualitative grading of the severity of the venous disease, and a quantitative scintigraphic index (saphena /femoral ratio) was assigned to each limb. The scintigraphic qualitative grading showed a highly significant correlation with the clinical grading (Rs=0.82, p<0.01), a good interobserver and intraobserver agreement (86.5% and 92.3%, respectively) and more than 90% sensitivity and specificity to identify the categories "minimal or no chronic venous disease" or "more significant disease" (assessed according to the Bayes theorem). Sensitivity and specificity results for the quantitative assessment were not as good. Phleboscintigraphy correlates well with the clinical grading of the severity of chronic venous disease of the lower limbs and may have potential as a valuable diagnostic tool for the noninvasive assessment of chronic venous disease.

Skeletal reconstruction with a free vascularized fibula graft associated to bone allograft after resection of malignant bone tumor of limbs

Over the last twenty years, progress in diagnosis and in adjuvant therapy in the field of malignant bone tumor treatment has allowed for development of limb-saving surgical techniques after oncological excision. In this context, the use of vascularized fibula for transplantation represents an important instrument in the reconstruction of bone, either with or without allografts.Moreover, in pediatric cases, the vascularized transplant of the proximal fibula with its open physis allows for an adequate reconstruction of the bone loss and the possibility of conserving the growth potential of the segment. The purpose of this article is to illustrate the various reconstructive possibilities that the use of the combined graft technique (VFT plus allograft) offers in the treatment of large-scale bone loss. In our department from 1988 to 2000, 142 vascularized fibula transplants were performed in oncological cases. Surgical reconstruction was carried out on the tibia in 70 cases, on the femur in 40, on the humerus in 26 and on the radius in 6. Combined graft intercalary reconstructions were 92. In 22 pediatric cases the fibula was transplanted, including the proximal growing epiphysis in the graft; in two of these cases massive allograft was associated to the VFG. Because of its biological properties, the grafted vascularized fibula allowed for fast bone fusion at the level of the osteotomy. It has also demonstrated a tendency of progressive hypertrophy and osteointegration with the allograft, when used. In 22 pediatric cases, the fibula graft with the proximal epiphysis maintained its ability to grow. Unsuccessful outcomes caused by vascular, mechanical, or septic failure were equal to 8.2 %. The fibula graft in the reconstruction of bone loss secondary to oncological excision is a trustworthy and versatile technique.

A murine osteosarcoma cell line with a potential to develop ossification upon transplantation

An osteosarcoma cell line has been established from a soft tissue tumor that occurred spontaneously in a BALB / c mouse. This cell line showed ossification when transplanted into syngeneic mice. To examine the mechanism of bone formation, the expression of mRNAs for osteoblastic and chondroblastic markers and factors associated with ossification has been investigated. In culture, the cells exhibited a spindle shape in the growth phase, but had a polygonal shape in the stationary phase. Reverse transcription-polymerase chain reaction analysis showed that the cells expressed mRNAs for pro-alpha1(I) chain of type I collagen, alkaline phosphatase, osteopontin, osteocalcin, and core binding factor alpha1, suggesting differentiation into the stage of osteoblasts during the stationary phase. After transplantation, histological examination revealed small foci of pale blue material and basophilic networks that were scattered in the tumor tissues at one week. The former stained positive with alcian blue, suggesting a chondroid matrix. Pro-alpha1(II) chain of type II collagen mRNA was expressed at one week. A large part of tumors at two and three weeks consisted of basophilic networks, which stained positive via von Kossa's method, indicating a calcified woven bone. In situ hybridization analysis showed strong expression of osteopontin and osteocalcin mRNAs in tumor cells surrounding the bone matrix. Bone morphogenetic protein-6 and -7 mRNAs were detected in transplanted tumors, but not in cultured cells. These results suggest that the cell line has the properties of an osteoblastic lineage when cultured in vitro and has an ossifying ability through endochondral bone formation processes when transplanted in vivo.

Dialysis access induced limb ischemia corrected using quantitative duplex ultrasound

Dialysis access induced limb ischemia (DAILI) is a rare complication after the creation of an arteriovenous fistula in infancy but can cause irreversible ischemic limb damage in severe cases. The incidence of DAILI is higher in bridge graft fistulas than in native fistulas. DAILI patients may be managed by surgically reducing the volume flow in the fistula. However, in the pediatric age group, such a reduction of volume flow may result in thrombosis or an inadequate flow for effective dialysis. Several methods have been described to achieve the delicate balance between essential flow in the fistula and adequate limb perfusion pressure. We have developed a new method employing preoperative duplex ultrasonography to predict quantitatively the reduction in volume flow in the fistula that will allow effective dialysis while providing adequate limb perfusion. The preoperative assessment was reproduced on the operating table using intraoperative duplex. A 3-year-old girl thus treated has had resolution of her ischemic symptoms and maintains long-term patency of her dialysis access.

Rate of abnormal osteoarticular radiographic findings in pediatric patients

OBJECTIVE

The objective of our study was to assess the rate of abnormal radiographic findings in the most frequent osteoarticular locations of traumatic injury in a pediatric population.

SUBJECTS AND METHODS

During two periods of 12 weeks each, all patients admitted to the pediatric emergency department for osteoarticular trauma who underwent radiography were prospectively included in this study. A connection was drawn between the rate of abnormal radiographic findings for the seven most frequently radiographed locations and the clinical findings.

RESULTS

Of 3128 locations of trauma in 2470 children, only 22% of the radiographic examinations were considered to reveal abnormal findings. In decreasing order, the hand and fingers, the ankle, the wrist, the knee, the elbow, the foot and toes, and the forearm were the most frequently examined locations. The rate of abnormal findings was 25.7% for the hand and fingers, 9.0% for the ankle, 42.5% for the wrist, 9.5% for the knee, 33.3% for the elbow, 18.3% for the foot, and 43.2% for the forearm. When only the direct sign of fracture was taken into account, these rates decreased for the ankle and knee to 2.6% and 1.9%, respectively. There was always a significant link between the degree of clinical suspicion and the rate of abnormal radiographic findings. However, fewer than 50% of the cases with high clinical suspicion of fracture were radiographically confirmed.

CONCLUSION

It appears necessary, especially in cases of lower limb trauma, to evaluate clinical tests, including the implementation of the Ottawa ankle rules, to reduce the number of unnecessary radiographic examinations. This reduction will improve some parameters of children's quality of life and will significantly decrease the cost of emergency care.