Multi-modality imaging of transient osteoporosis of the hip.

Transient osteoporosis of the hip (TOH), also referred to as bone marrow edema syndrome (BMES) of the femoral head and neck, is an uncommon and therefore underdiagnosed benign skeletal disorder, affecting primarily women, particularly in their last trimester of pregnancy, and middle-aged men. The disease is characterized by self-limiting hip pain and radiographically evident osteopenia, but these radiographic findings can sometimes be delayed. In the early phase, the main diagnostic dilemma lies in differentiating TOH from osteonecrosis of the femoral head (ONFH). Conventional radiographs, Tc-99m bone scans (multiphase, SPECT or SPECT/CT) and MRI scans from 10 male patients with 12 TOH episodes were retrospectively and independently reviewed by two nuclear medicine physicians and a musculoskeletal radiologist. The purpose was to identify a typical imaging pattern, and secondly, to reliably distinguish TOH from ONFH. In the early phase of TOH, conventional radiography of the hip could not sufficiently detect focal osteopenia. But in all 10 patients (mean age 45 years, range, 34-62), bone scans and MRI scans demonstrated a similar pattern of diffuse hyperaemia, bony uptake, and bone marrow edema in the femoral head and neck, extending to and ending with a sharp demarcation at the intertrochanteric region. Additionally, neither SPECT nor SPECT/CT nor MRI revealed any cold area or crescent-shaped subchondral defect in the femoral head, indicating ONFH. In some cases there was a joint effusion in varying degree. In 9 patients, an uneventful recovery was eventually observed. Scintigraphically diffuse hyperaemic and/or homogeneous osseous uptake in femoral head and neck extending to the intertrochanteric region, as well as the recently introduced term transient bone marrow edema syndrome (BMES) of the hip on MRI, are probably both expressions of the same pathophysiological mechanism, and pathognomonic for TOH. Hopefully, recognizing this highly specific imaging pattern will exclude in the future more aggressive skeletal diseases like ONFH, severe arthritis, osteomyelitis or even malignancy.

US-guided injection of the upper and lower extremity joints.

There is a growing interest in the application of ultrasound (US) guidance for diagnostic and therapeutic joint injections. US provides direct visualization of soft tissues and the outer borders of bony structures. With real-time needle guidance the success rate of intra-articular injections improves and iatrogenic damage to anatomic structures can be avoided. An US machine is more readily available, transferrable and more affordable than a fluoroscopy machine or CT scanner and lacks the risk of radiation. These factors make US a valuable alternative to procedures performed either blind or under fluoroscopic or CT guidance. This article focuses on the rationale for injections in the upper and lower extremity joints and describes and illustrates the different US-guided injection techniques.

Unsuspected sonographic findings in patients with posttraumatic shoulder complaints.

PURPOSE: To prospectively assess the frequency of abnormal sonographic findings in patients with posttraumatic shoulder pain and/or disability in whom ultrasound (US) was not considered and to assess the effect of sonographic findings on working diagnosis and therapeutic strategy, to analyze the possible role of US in the diagnostic workup of these patients. METHODS: A survey was performed under general practitioners and orthopedic surgeons. They were requested to refer patients with persistent posttraumatic complaints for an US examination of the shoulder and to fill out a questionnaire concerning working diagnosis and therapy. In 50 patients examinations were performed separately by two radiologists. Findings were confirmed with additional radiographs and/or MRI and/or surgery. Four weeks after the US examination, the survey was repeated to inquire about changes in diagnosis and/or treatment that resulted from US. RESULTS: US showed relevant pathology in 45 (90%) of 50 patients, a proximal humerus fracture in 25 (50%) patients, and a rotator cuff tear in 43 (86%) patients. Twenty-three (92%) fractures were accompanied by a rotator cuff tear, and 23 (54%) rotator cuff tears were accompanied by a fracture. Ten fractures were initially missed radiographically. US findings changed the working diagnosis and therapeutic strategy in 37 (74%) and 26 (52%) patients, respectively. CONCLUSION: In patients with posttraumatic shoulder complaints, US showed a high rate (90%) of relevant pathology. This changed the initial working diagnosis in 74% of the patients and the therapeutic strategy in more than half of the patients. Active referral for US examination may identify these abnormalities in an earlier phase and improve clinical outcome.

Early monitoring of the viability of the buried intrathoracic omental flap: a feasibility study.

PURPOSE: The value of mobile, high-resolution gray-scale and color Doppler ultrasonography (US) in the immediate postoperative, intensive care setting for monitoring the buried flap and vascular pedicle of the laparoscopic or transdiaphragmatic harvested omentum for intrathoracic reconstruction was evaluated. In addition to flow, flap position, size, and findings of flap necrosis, other flap-related complications were investigated. DESCRIPTION: Two patients with deep sternal wound infection after coronary artery bypass grafting suspected with impending flap failure and reoperation in the immediate postreconstructive period were examined with a Philips HDI-5000 US scanner (Philips Medical Systems, Best, The Netherlands) equipped with an L12-5 MHz linear-array transducer at the bedside. The US findings were defined and the therapeutic decisions that were made based on the information gleaned, were compared with computed tomography controls and the eventual clinical outcomes. EVALUATION: Flow and flap viability could easily and repeatedly be demonstrated and recorded with the aid of high-resolution gray-scale and color-Doppler US. Despite the unusual, buried position of the pedicle and omental flap, the information gleaned was sufficient to reach a decision that prevented unnecessary surgery. CONCLUSIONS: Mobile high-resolution gray-scale US, combined with color Doppler US, was confirmed to be accurate and promises to be a valuable noninvasive tool for the immediate postoperative assessment of pedicle and intrathoracic omental flap perfusion and viability. It may also avert unnecessary and difficult surgical revision of an elegant but sensitive flap reconstruction.

Expanding role of 18F-fluoro-D-deoxyglucose PET and PET/CT in spinal infections.

(18)F-fluoro-D -deoxyglucose positron emission tomography ([(18)F]-FDG PET) is successfully employed as a molecular imaging technique in oncology, and has become a promising imaging modality in the field of infection. The non-invasive diagnosis of spinal infections (SI) has been a challenge for physicians for many years. Morphological imaging modalities such as conventional radiography, computed tomography (CT), and magnetic resonance imaging (MRI) are techniques frequently used in patients with SI. However, these methods are sometimes non-specific, and difficulties in differentiating infectious from degenerative end-plate abnormalities or postoperative changes can occur. Moreover, in contrast to CT and MRI, FDG uptake in PET is not hampered by metallic implant-associated artifacts. Conventional radionuclide imaging tests, such as bone scintigraphy, labeled leukocyte, and gallium scanning, suffer from relatively poor spatial resolution and lack sensitivity, specificity, or both. Initial data show that [(18)F]-FDG PET is an emerging imaging technique for diagnosing SI. [(18)F]-FDG PET appears to be especially helpful in those cases in which MRI cannot be performed or is non-diagnostic, and as an adjunct in patients in whom the diagnosis is inconclusive. The article reviews the currently available literature on [(18)F]-FDG PET and PET/CT in the diagnosis of SI.

Glenohumeral joint injection: a comparative study of ultrasound and fluoroscopically guided techniques before MR arthrography.

To assess the variability in accuracy of contrast media introduction, leakage, required time and patient discomfort in four different centres, each using a different image-guided glenohumeral injection technique. Each centre included 25 consecutive patients. The ultrasound-guided anterior (USa) and posterior approach (USp), fluoroscopic-guided anterior (FLa) and posterior (FLp) approach were used. Number of injection attempts, effect of contrast leakage on diagnostic quality, and total room, radiologist and procedure times were measured. Pain was documented with a visual analogue scale (VAS) pain score. Access to the joint was achieved in all patients. A successful first attempt significantly occurred more often with US (94%) than with fluoroscopic guidance (72%). Leakage of contrast medium did not cause interpretative difficulties. With US guidance mean room, procedure and radiologist times were significantly shorter (p < 0.001). The USa approach was rated with the lowest pre- and post-injection VAS scores. The four image-guided injection techniques are successful in injection of contrast material into the glenohumeral joint. US-guided injections and especially the anterior approach are significantly less time consuming, more successful on the first attempt, cause less patient discomfort and obviate the need for radiation and iodine contrast.