Diagnostic value of combined 18F-FDG PET/MRI for staging and restaging in paediatric oncology

Purpose

The present study compares the diagnostic value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and MRI to combined/registered ¹⁸F-FDG PET/MRI for staging and restaging in paediatric oncology.

Methods

Over 8?years and 2?months, 270 ¹⁸F-FDG PET and 270 MRI examinations (mean interval 5?days) were performed in 132 patients with proven (n?=?117) or suspected (n?=?15) malignant disease: solid tumours (n?=?64), systemic malignancy (n?=?53) and benign disease (n?=?15). A total of 259 suspected tumour lesions were analysed retrospectively during primary diagnosis and 554 lesions during follow-up. Image analysis was performed separately on each modality, followed by analysis of combined and registered ¹⁸F-FDG PET/MRI imaging.

Results

A total of 813 lesions were evaluated and confirmed by histopathology (n?=?158) and/or imaging follow-up (n?=?655) after 6?months. In the separate analysis of ¹⁸F-FDG PET and MRI, sensitivity was 86?%/94?% and specificity 85?%/38?%. Combined/registered ¹⁸F-FDG PET/MRI led to a sensitivity of 97?%/97?% and specificity of 81?%/82?%. False-positive results (¹⁸F-FDG PET n?=?69, MRI n?=?281, combined ¹⁸F-FDG PET/MRI n?=?85, registered ¹⁸F-FDG PET/MRI n?=?80) were due to physiological uptake or post-therapeutic changes. False-negative results (¹⁸F-FDG PET n?=?50, MRI n?=?20, combined ¹⁸F-FDG PET/MRI n?=?11, registered ¹⁸F-FDG PET/MRI n?=?11) were based on low uptake or minimal morphological changes. Examination-based evaluation during follow-up showed a sensitivity/specificity of 91?%/81?% for ¹⁸F-FDG PET, 93?%/30?% for MRI and 96?%/72?% for combined ¹⁸F-FDG PET/MRI.

Conclusion

For the detection of single tumour lesions, registered ¹⁸F-FDG PET/MRI proved to be the methodology of choice for adequate tumour staging. In the examination-based evaluation, MRI alone performed better than ¹⁸F-FDG PET and combined/registered imaging during primary diagnosis. At follow-up, however, the examination-based evaluation demonstrated a superiority of ¹⁸F-FDG PET alone.     

Focal cortical dysplasia type IIa and IIb: MRI aspects in 118 cases proven by histopathology

Introduction

This study aims to review the magnetic resonance imaging (MRI) aspects of a large series of patients with focal cortical dysplasia type II (FCD II) and attempt to identify distinctive features in the two histopathological subtypes IIa and IIb.

Methods

We retrospectively reviewed the MRI scans of 118 patients with histological proven FCD IIa (n?=?37) or IIb (n?=?81) who were surgically treated for intractable epilepsy.

Results

MRI was abnormal in 93 patients (79?%) and unremarkable in 25 (21?%). A dysplastic lesion was identified in 90 cases (97?%) and classified as FCD II in 83 and FCD non-II in seven cases. In three cases, the MRI diagnosis was other than FCD. There was a significant association between the presence of cortical thickening (p?=?0.002) and the “transmantle sign” (p?<?0.001) and a correct MRI diagnosis of FCD II. MRI positivity was more frequent in the patients with FCD IIb than in those with FCD IIa (91?% vs. 51?%), and the detection rate of FCD II was also better in the patients with type IIb (88?% vs. 32?%). The transmantle sign was significantly more frequent in the IIb subgroup (p?=?0.003).

Conclusions

The rates of abnormal MRI results and correct MRI diagnoses of FCD II were significantly higher in the IIb subgroup. Although other MRI stigmata may contribute to the diagnosis, the only significant correlation was between the transmantle sign and FCD IIb.     

Response assessment of bevacizumab in patients with recurrent malignant glioma using [18F]Fluoroethyl-l-tyrosine PET in comparison to MRI

Purpose

To investigate prospectively the potential of O-(2-[¹⁸F]fluoroethyl)-l-tyrosine (¹⁸F-FET) PET in comparison to MRI for the assessment of the response of patients with recurrent high-grade glioma (rHGG) to antiangiogenic treatment.

Methods

Ten patients with rHGG were treated biweekly with bevacizumab/irinotecan (BEV/IR). MR images and dynamic ¹⁸F-FET PET scans were obtained at baseline and at follow-up after the start of treatment (median 4.9 weeks). Using MRI treatment response was evaluated according to RANO (Response Assessment in Neuro-Oncology) criteria. For ¹⁸F-FET PET evaluation, a reduction >45?% of the metabolically active tumour volume was considered as a treatment response, with the metabolically active tumour being defined as a tumour-to-brain ratio (TBR) of ??1.6. The results of the treatment assessments were related to progression-free survival (PFS) and overall survival (OS). For further evaluation of PET data, maximum and mean TBR were calculated using region-of-interest analysis at baseline and at follow-up. Additionally, ¹⁸F-FET uptake kinetic studies were performed at baseline and at follow-up in all patients. Time?Cactivity curves were generated and the times to peak (TTP) uptake (in minutes from the beginning of the dynamic acquisition to the maximum uptake) were calculated.

Results

At follow-up, MRI showed a complete response according to RANO criteria in one of the ten patients (10?%), a partial response in five patients (50?%), and stable disease in four patients (40?%). Thus, MRI did not detect tumour progression. In contrast, ¹⁸F-FET PET revealed six metabolic responders (60?%) and four nonresponders (40?%). In the univariate survival analyses, a response detected by ¹⁸F-FET PET predicted a significantly longer PFS (median PFS, 9 vs. 3 months; P?=?0.001) and OS (median OS 23.0?months vs. 3.5 months; P?=?0.001). Furthermore, in four patients (40?%), diagnosis according to RANO criteria and by ¹⁸F-FET PET was discordant. In these patients, PET was able to detect tumour progression earlier than MRI (median time benefit 10.5?weeks; range 6?C12?weeks). At baseline and at follow-up, in nonresponders TTP was significantly shorter than in responders (baseline TTP 10?±?8?min vs. 35?±?9?min; P?=?0.002; follow-up TTP 23?±?9?min vs. 39?±?8?min; P?=?0.02). Additionally, at baseline a kinetic pattern characterized by an early peak of ¹⁸F-FET uptake followed by a constant descent was more frequently observed in the nonresponders (P?=?0.018).

Conclusion

Both standard and kinetic imaging parameters derived from¹⁸F-FET PET seem to predict BEV/IR treatment failure and thus contribute important additional information for clinical management over and above the information obtained by MRI response assessment based on RANO criteria.     

Role of scintigraphy with 99mTc-infliximab in predicting the response of intraarticular infliximab treatment in patients with refractory monoarthritis

Purpose

The rationale for the present study was to evaluate the predictive role of ^99mTc-infliximab scintigraphy in therapy decision-making in patients with refractory monoarthritis and also candidates for intraarticular (IA) infliximab treatment.

Methods

We studied 12 patients (5 with rheumatoid arthritis and 7 with spondyloarthropathy) with active monoarthritis (11 knees and 1 ankle) that had lasted for at least 3?months. Patients were evaluated clinically and ultrasonographically at baseline and 12?weeks after IA administration of infliximab. At the same time-points, ^99mTc-infliximab scintigraphy was performed: planar anterior and posterior images of arthritic joints were acquired at 6 and 20?h after injection and target-to-background (T/B) ratios were calculated.

Results

After treatment, a significant improvement in clinical and ultrasonographic parameters was recorded in six patients. Three patients had a partial response and three did not respond. Regarding scintigraphic evaluation, the T/B ratio analysis showed a significantly higher uptake in affected than in nonaffected joints before therapy (1.78?±?0.46 vs. 1.29?±?0.27, p?=?0.006 at 6?h; 2.05?±?0.50 vs. 1.41?±?0.36 at 20?h, p?=?0.002), and mean uptake at 20?h was also significantly higher than at 6?h (p?=?0.0004). Scintigraphy showed a significant decrease in posttherapy T/B ratios of the affected joints (p?=?0.0001 at 6?h and p?=?0.0001 at 20?h), indicating a reduction in TNF into the affected joints. Most importantly, responders showed a significantly higher percentage increase in pretherapy uptake from 6?h to 20?h in the affected joints than nonresponders (p?=?0.00001).

Conclusion

The results of the present investigation suggest that ^99mTc-infliximab scintigraphy could be a useful tool to predict the clinical response to IA infliximab treatment in patients with refractory monoarthritis.     

Detection and treatment of spinal CSF leaks in idiopathic intracranial hypotension

Introduction

This study aimed to evaluate the diagnostic imaging findings and treatment results of patients with idiopathic intracranial hypotension (IIH) due to cerebrospinal fluid (CSF) leaks.

Methods

Between February 2009 and April 2012, 26 IIH patients (15 men, median age 49?years) presenting with orthostatic headache (n?=?20) and/or with spontaneous subdural effusions or subarachnoid hemorrhage (n?=?19) were enrolled. Twenty-three patients underwent a whole spine CT and MRI myelography, starting 45?min after the intrathecal injection of 9?cc of iomeprol (Imeron 300 M) and 1?cc of gadobutrolum (Gadovist). Three patients only underwent MR myelography after intrathecal gadobutrolum injection. Adjacent to the level(s) of the detected CSF leak(s) along the nerve roots, 20?cc of fresh venous blood with 0.5?cc Gadovist was injected epidurally (blood patch, BP). The distribution of the BP was visualized by MRI the following day. Treatment results were evaluated clinically and by myelography 2?weeks after the application of the BP. Retreatment was offered to patients with persistent symptoms and continued CSF leakage.

Results

CSF leaks were detected at the cervical (n?=?12), thoracic (n?=?25), or lumbar (n?=?21) spine. In 23 patients, more than one spinal segment was affected. One patient refused treatment. BP were applied in one (n?=?9) or several (n?=?16) levels. Clinical and/or radiological improvement was achieved after one (n?=?16), two (n?=?5), three (n?=?3), or five (n?=?1) BPs.

Conclusion

CT and MRI myelography allow the reliable detection of spinal CSF leaks. The targeted and eventually repeated epidural BP procedure is a safe and efficacious treatment.     

MRI of the breast in patients with DCIS to exclude the presence of invasive disease

Objectives

Core biopsy underestimates invasion in more than 20% of patients with preoperatively diagnosed ductal carcinoma in situ (DCIS) without evidence of invasion (pure DCIS). The aim of the current study was to evaluate the efficacy of preoperative magnetic resonance imaging (MRI) to discriminate between patients with DCIS who are at high risk of invasive breast cancer and patients at low risk.

Methods

One hundred and twenty-five patients, preoperatively diagnosed with pure DCIS (128 lesions; 3 bilateral) by core-needle biopsy, were prospectively included. Clinical, mammographic, histological (core biopsy) and MRI features were assessed. All patients underwent breast surgery. Analyses were performed to identify features associated with presence of invasion.

Results

Eighteen lesions (14.1%) showed invasion on final histology. Seventy-three lesions (57%) showed suspicious enhancement on MRI with a type 1 (n?=?12, 16.4%), type 2 (n?=?19, 26.0%) or type 3 curve, respectively (n?=?42, 57.5%). At multivariate analysis, the most predictive features for excluding presence of invasive disease were absence of enhancement or a type 1 curve on MRI (negative predictive value 98.5%; A_Z 0.80, P?=?0.00006).

Conclusion

Contrast medium uptake kinetics at MRI provide high negative predictive value to exclude presence of invasion and may be useful in primary surgical planning in patients with a preoperative diagnosis of pure DCIS.

Key Points

? It is important to determine invasion in breast DCIS. ? MRI contrast medium uptake kinetics can help exclude the presence of invasion. ? However, the positive predictive value for the presence of invasion is limited. ? MRI features were more accurate at predicting invasion than mammographic features alone.     

Obesity increases the prevalence and severity of focal knee abnormalities diagnosed using 3T MRI in middle-aged subjects—data from the Osteoarthritis Initiative

Objective

To study the effect of BMI on the prevalence, severity, and 36-month progression of early degenerative changes in the knee by using 3T MRI in middle-aged subjects without radiographic osteoarthritis (OA).

Materials and methods

We examined baseline and 36-month follow-up MR studies from 137 middle-aged individuals (45-55 years old) with risk factors for knee OA but no radiographic OA from the Osteoarthritis Initiative. Subjects were grouped into three categories: normal BMI (BMI?2, n?=?38), overweight (BMI 25–29.9 kg/m², n?=?37), and obese (BMI ≥ 30 kg/m², n?=?62). Using 3T MRI, cartilage, meniscus, and bone marrow abnormalities were graded using the OA Whole-organ MR Imaging Score (WORMS). The statistical analysis was corrected as necessary for differences in age, sex, and OA risk factors other than BMI.

Results

The overall prevalence of lesions was 64% for meniscus and 79% for cartilage (including low grade lesions). At baseline, the prevalence and severity of knee lesions was positively associated with BMI, with a nearly fourfold increase in meniscal tears and more than twofold increase in high-grade cartilage defects in obese individuals relative to normal-weight subjects. Over the 36-month follow-up period, the number of new or worsening cartilage lesions of any grade was significantly higher in obese subjects (p?=?0.039), while there was no significant difference in meniscal lesion progression.

Conclusion

Obesity was associated with both higher prevalence and severity of early degenerative changes in the knee in middle-aged individuals without radiographic OA and with significantly increased cartilage lesion progression (of any grade) over 36 months.     

Ten Years of Experience with the GORE EXCLUDER? Stent-Graft for the Treatment of Aortic and Iliac Aneurysms: Outcomes from a Single Center Study

Purpose

This study was designed to assess the long-term outcome of selected patients with aortic, aortoiliac, and isolated common iliac aneurysms treated with the GORE EXCLUDER^? stent-graft.

Methods

Between December 1998 and June 2010, 121 nonconsecutive patients underwent insertion of a GORE EXCLUDER^? stent-graft to treat an aortic (n?=?80; 66%), aortoiliac (n?=?25; 21%), or isolated common iliac (n?=?16; 13%) aneurysm. Procedural and follow-up data were collected prospectively. Primary endpoints are overall survival, intervention-free survival, and freedom from aneurysm rupture. Secondary endpoints are device- and procedure-related complications, including all types of endoleaks or endotension, and reintervention.

Results

The mean follow-up is 4.98?years (standard deviation, 3.18; median follow-up, 4.05?years). The estimated percentage overall survival (with 95% confidence interval) after respectively 5 and 10?years of follow-up is 74.5% (65.8; 81.3) and 57.8% (47.7; 66.7). The estimated intervention-free survival after respectively 5 and 10?years is 90% (84.3; 96.1) and 77.7% (67; 88.4). There was no aneurysm rupture during follow-up. Early postoperative complications occurred in 16 patients (13%); none were fatal. Late reinterventions were performed in 18?patients (15%). Finally, throughout the follow-up period, endoleaks were identified: type I (n?=?4; 3%); type II (n?=?39; 32%); type?III (n?=?0; 0%); endotension was seen in 11 patients (9%).

Conclusions

Aneurysm exclusion with use of the GORE EXCLUDER^? stent-graft is durable through a mean follow-up of nearly 5?years. There was no postprocedural aneurysm rupture. Complications occurred throughout the follow-up period, requiring continued clinical and radiological surveillance.     

Diffusion-weighted MR imaging of fetal lung maturation in sheep: effect of prenatal cortisone administration on ADC values

Objective

To assess changes in diffusion properties in the fetal lung after cortisone administration with diffusion-weighted imaging (DWI) in fetal sheep.

Methods

DWI was performed on 11 pregnant sheep with singleton pregnancies on a 1.5-T MRI scanner. Four animals received cortisone injections before baseline imaging. Seven animals served as controls. Apparent diffusion coefficient (ADC) was measured on DWI in the fetal lungs by two independent readers. The Pearson test was used to correlate ADC and gestational age. A t-test was performed to compare differences in ADC values at the baseline and follow-up images within and between groups. Inter-rater reliability was calculated.

Results

In the cortisone group, ADC values increased about 10 % between the baseline and follow-up images (P?=?0.039). Comparing the cortisone and control groups, ADC values of the baseline images did not differ; whereas in the follow-up imaging, ADC values were significantly higher in the cortisone group (P?=?0.024). Lung ADC values did not correlate with gestational age (P?=?0.970). Inter-rater reliability was high (0.970, P?=?0.000).

Conclusion

In this experimental model, MR-DWI can detect cortisone-induced changes in diffusion properties of the fetal lung.

Key Points

? Corticosteroids are frequently administered antenatally to prevent fetal lung immaturity at birth ? DWI can detect changes in the fetal lung after corticosteroid administration ? Changes can be detected as early as 5 days after treatment ? Fetal MRI may offer a non-invasive method of monitoring lung maturation     

Physiologic characterization of inflammatory arthritis in a rabbit model with BOLD and DCE MRI at 1.5 Tesla

Objective

Our aim was to test the feasibility of blood oxygen level dependent magnetic resonance imaging (BOLD MRI) and dynamic contrast-enhanced (DCE) MRI to monitor periarticular hypoxic/inflammatory changes over time in a juvenile rabbit model of arthritis.

Methods

We examined arthritic and contralateral nonarthritic knees of 21 juvenile rabbits at baseline and days 1,14, and 28 after induction of arthritis by unilateral intra-articular injection of carrageenin with BOLD and DCE MRI at 1.5 Tesla (T). Nine noninjected rabbits served as controls. Associations between BOLD and DCE-MRI and corresponding intra-articular oxygen pressure (PO₂) and blood flow [blood perfusion units (BPU)] (polarographic probes, reference standards) or clinical–histological data were measured by correlation coefficients.

Results

Percentage BOLD MRI change obtained in contralateral knees correlated moderately with BPU on day 0 (r?=??0.51, p?=?0.02) and excellently on day 28 (r?=??0.84, p?=?0.03). A moderate correlation was observed between peak enhancement DCE MRI (day 1) and BPU measurements in arthritic knees (r?=?0.49, p?=?0.04). In acute arthritis, BOLD and DCE MRI highly correlated (r?=?0.89, p?=?0.04; r?=?1.0, p?Conclusion The proposed techniques are feasible to perform at 1.5 T, and they hold potential as surrogate measures to monitor hypoxic and inflammatory changes over time in arthritis at higher-strength MRI fields.

Key points

? BOLD and DCE MRI detect interval perisynovial changes in a rabbit knee ? BOLD and DCE MRI act as surrogate markers of physiologic changes in arthritis ? BOLD MRI signal represents oxygen extraction compared with intra-articular PO ₂ ? DCE MRI measurements estimate physiologic periarticular vascular properties ? In rabbit knees with acute arthritis, BOLD/DCE MRI highly correlated with histological scores     

Characterisation of hand small joints arthropathy using high-resolution MRI—Limited discrimination between osteoarthritis and psoriatic arthritis

Objective

To test the hypothesis that microanatomical differences in joint disease localisation could be exploited using high-resolution MRI to better differentiate among rheumatoid arthritis (RA), spondyloarthritis/psoriatic arthritis (SpA/PsA) and osteoarthritis (OA) in clinical practice.

Methods

Sixty-nine patients with suspected inflammatory joint disease of the hand or feet underwent high-resolution MRI using a small loop coil. Images were scored blinded to the clinical status. Various joint changes like periostitis, osteitis, erosions, enthesitis and synovitis were recorded. The image-based diagnosis was compared with the clinical diagnosis.

Results

In 59.4 % of the patients the clinical diagnosis was confirmed on image analysis. This was high for OA (80 %), moderately good for RA (67 %) but only 50 % for SpA/PsA. The major difficulty was to distinguish OA from SpA/PsA where common imaging findings are evident including periostitis (SpA/PsA 45 %, OA 40 % compared with RA 0 %; P?=?0.015). Likewise, osteitis was frequently detected in SpA/PsA (79 %) and OA (80 %) and less frequently in RA (42 %) (P?=?0.014).

Conclusion

Characterisation of inflammatory disorders of small joints merely using high-resolution MRI remains challenging especially in the differentiation between OA and PsA. These findings are likely explained by common microanatomical similarities in disease expression rather than limitations of imaging techniques.

Key Points

? High-resolution MRI is increasingly used to investigate joint disease. ? Osteitis and periostitis occur in psoriatic and osteoarthritis (but not rheumatoid arthritis). ? In severely affected patients the amount of synovitis and erosions is similar.     

Short-term evolution of spinal cord damage in multiple sclerosis: a diffusion tensor MRI study

Introduction

The potential of diffusion tensor imaging (DTI) to detect spinal cord abnormalities in patients with multiple sclerosis has already been demonstrated. The objective of this study was to apply DTI techniques to multiple sclerosis patients with a recently diagnosed spinal cord lesion, in order to demonstrate a correlation between variations of DTI parameters and clinical outcome, and to try to identify DTI parameters predictive of outcome.

Methods

A prospective single-centre study of patients with spinal cord relapse treated by intravenous steroid therapy was made. Patients were assessed clinically and by conventional MRI with DTI sequences at baseline and at 3?months.

Results

Sixteen patients were recruited. At 3?months, 12 patients were clinically improved. All but one patient had lower fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values than normal subjects in either inflammatory lesions or normal-appearing spinal cord. Patients who improved at 3?months presented a significant reduction in the radial diffusivity (p?=?0.05) in lesions during the follow-up period. They also had a significant reduction in the mean ADC (p?=?0.002), axial diffusivity (p?=?0.02), radial diffusivity (p?=?0.02) and a significant increase in FA values (p?=?0.02) in normal-appearing spinal cord. Patients in whom the American Spinal Injury Association sensory score improved at 3?months showed a significantly higher FA (p?=?0.009) and lower radial diffusivity (p?=?0.04) in inflammatory lesion at baseline compared to patients with no improvement.

Conclusion

DTI MRI detects more extensive abnormalities than conventional T2 MRI. A less marked decrease in FA value and more marked decreased in radial diffusivity inside the inflammatory lesion were associated with better outcome.     

Clinical value of magnetic resonance imaging in patients with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome: diagnosis of associated malformations,uterine rudiments and intrauterine endometrium

Objectives

The aim of this study was to evaluate the accuracy of preoperative magnetic resonance imaging (MRI) in the diagnosis of malformations associated with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome and identification of uterine endometrium to optimise the clinical management.

Methods

We retrospectively reviewed 214 consecutive MRKH patients, mean age 19 years, who underwent laparoscopy-assisted neovagina creation. A total of 115 patients (53.7 %) met the inclusion criterion of sufficient preoperative MRI. In 110 of them (95.7 %), MRI findings were correlated with laparoscopy and associated malformations. In 39 cases (35.5 %) uterine rudiments were removed and analysed histopathologically.

Results

Ten per cent (11/110) of the patients showed complete uterine agenesis. The others presented with either unilateral (n?=?16; 14.5 %) or bilateral (n?=?83; 75.5 %) uterine rudiments. MRI detection of uterine rudiments agreed in 78.2 % (86/110) with laparoscopy. In 85.4 % of the removed rudiments, MRI could correctly diagnose the existence of the endometrium. Compared to laparoscopy, MRI could exactly detect ovaries in 97.3 % (107/110). Renal or ureteral malformations were seen in 32 cases (27.8 %). In 83 % of unilateral renal agenesis and unilateral rudiment, the latter was located at the side of the kidney.

Conclusions

MRI is useful for preoperative detection of MRKH-associated malformations and assessment of the endometrium to further optimise MRKH patient treatment.

Key points

? Pelvic MRI is useful for preoperative detection of MRKH-associated malformations. ? MRI can diagnose uterine endometrium in MRKH patients with high precision. ? Preoperative MRI can optimise clinical management of patients with MRKH syndrome.     

The iliotibial band in acute knee trauma: patterns of injury on MR imaging

Objective

To delineate the spectrum of knee injuries associated with sprains and tears of the distal iliotibial band (ITB).

Materials and methods

A retrospective review of 200 random MRI scans undertaken for acute knee trauma was performed. Scans were excluded if there was a history of injury over 4 weeks from the time of the scan, septic arthritis, inflammatory arthropathy, previous knee surgery, or significant artefact. In each scan, the ITB was scored as normal, minor sprain (grade 1), severe sprain (grade 2), and torn (grade 3). The menisci, ligaments, and tendons of each knee were also assessed.

Results

The mean age was 27.4 years (range, 9–69 years) and 71.5 % (n?=?143) of the patients were male. The ITB was injured in 115 cases (57.5 %). The next most common soft tissue structure injured was the anterior cruciate ligament (ACL) in 53.5 % of cases (n?=?107). Grade 1 ITB injury was seen in 90 of these 115 cases (45 %), grade 2 injury in 20 cases, and grade 3 injury in only five cases. There is a significant association between ITB injury and ACL rupture (p?p?Conclusions ITB injury is common in acute knee trauma and is associated with significant internal derangement of the knee, especially cruciate ligament rupture, posterolateral corner injury, and patellar dislocation.     

Epiphyseal stress fractures of finger phalanges in adolescent climbing athletes: a 3.0-Tesla magnetic resonance imaging evaluation

Objectives

To study the value of 3.0-Tesla magnetic resonance imaging for baseline and follow-up assessment of epiphyseal finger phalanx stress fractures in a collective of 7 consecutive adolescent climbing athletes.

Materials and methods

Baseline MRI was performed in 8 fingers of 7 adolescent athletes (mean age 13.8 years, female:male?=?2:5) with clinically suspected stress fracture of the fingers acquired during climbing sports. Follow-up MRI was performed after functional therapy with training interruption for 6 weeks (n?=?6) and 12 weeks (n?=?1). Images were analysed retrospectively and independently by two readers using an MRI grading score from 0 (no pathology) to 4 (bone marrow oedema and clear depiction of a sharp fracture line with surrounding inflammatory soft tissue reaction).

Results

A total of 8 baseline and 7 follow-up MRIs were analysed. In 7 out of 8 fingers a stress fracture line Salter–Harris III and in all fingers a bone marrow oedema were diagnosed at the epiphyseal base of the middle phalanx. The average grading score was 3.37 in the initial MRI and 1.43 in the follow-up MRI indicating fracture healing in all fingers. Kappa value for interobserver variability was 0.86, representing almost perfect interobserver agreement.

Conclusions

3-T MRI is a promising diagnostic technique for baseline assessment of epiphyseal finger phalanx stress fractures and for follow-up evaluation of fracture healing.     

Factors affecting long-term restenosis after carotid stenting for carotid atherosclerotic disease

Introduction

The most significant factors leading to restenosis are yet to be described in the literature. The purpose of our study was to identify the incidence of restenosis in our patients with carotid artery stenting (CAS) for carotid atherosclerotic disease and to identify risk factors that are significantly responsible or related to the restenosis.

Methods

In this retrospective analysis of patients who underwent CAS for atherosclerotic disease between years 2002 and 2006, we studied various demographic, clinical, and medical factors, plaque characteristics, and technical aspects of CAS. All patients were followed up with carotid Doppler ultrasound at baseline (after 2 to 4?weeks of CAS) and then with Doppler ultrasound and clinically for various intervals of time. The restenosis was classified based on carotid Doppler ultrasound results. Clinically, restenosis was classified as symptomatic or asymptomatic. Pearson correlation coefficient was used to assess the statistical correlation of the different factors with the incidence of restenosis.

Results

We had a total of 105 patients, with a total of 204.6 patient-year follow-up (mean, 1.95?years; range, 0?C7.3?years). The overall incidence of restenosis was 26.7?% (n?=?28): mild, 7.6?% (n?=?8); moderate, 10.5?% (asymptomatic, 11; symptomatic, 0); and severe, 8.6?% (asymptomatic, 5; symptomatic, 4). Overall, 14.3?% (n?=?4) patients with restenosis were symptomatic and 7.1?% (n?=?2) underwent retreatment. Post-stenting residual stenosis greater than either 30?% (p?=?0.016) or 50?% (p?=?0.05) were significant for long-term restenosis. Plaques longer than 20?mm were significantly related to restenosis (p?<?0.001).

Conclusion

The most important factor to explain restenosis was the immediate post-CAS residual stenosis and length of the plaque.     

Gadoxetic acid enhanced MRI for differentiation of FNH and HCA: a single centre experience

Objectives

Evaluation of enhancement characteristics of histopathologically confirmed focal nodular hyperplasias (FNHs) and hepatocellular adenomas (HCAs) with gadoxetic acid-enhanced MRI.

Methods

Sixty-eight patients with 115 histopathologically proven lesions (FNHs, n?=?44; HCAs, n?=?71) examined with gadoxetic acid-enhanced MRI were retrospectively enrolled (standard of reference: surgical resection, n?=?53 patients (lesions: FNHs, n?=?37; HCAs, n?=?53); biopsy, n?=?15 (lesions: FNHs, n?=?7; HCAs, n?=?18)). Two radiologists evaluated all MR images regarding morphological features as well as the vascular and hepatocyte-specific enhancement in consensus.

Results

For the hepatobiliary phase, relative enhancement of the lesions and lesion to liver enhancement were significantly lower for HCAs (mean, 48.7 (±48.4) % and 49.4 (±33.9) %) compared to FNHs (159.3 (±92.5) %; and 151.7 (±79) %; accuracy of 89 % and 90 %, respectively; P?<?0.001). Visual strong uptake of FNHs vs. hypointensity of HCAs in the hepatobiliary phase resulted in an accuracy of 92 %. This parameter was superior to all other morphological and dynamic vascular criteria alone and in combination (accuracy, 54–85 %).

Conclusions

For differentiation of FNHs and HCAs by means of MRI, gadoxetic acid uptake in the hepatobiliary phase was found to be superior to all other criteria alone and in combination.

Key Points

? EOB-MRI is well suited to differentiate FNHs and hepatocellular adenomas. ? For this purpose hepatobiliary phase is superior to unenhanced and dynamic imaging. ? Hepatobiliary phase (peripheral) hyper- or isointensity is typical for FNH. ? Hepatobiliary phase hypointensity is typical for hepatocellular adenomas. ? EOB-MRI helps to avoid misinterpretations of benign hepatocellular lesions.     

Frequency and predictors of endoleaks and long-term patency after covered stent placement for the treatment of intracranial aneurysms: a prospective, non-randomised multicentre experience

Objective

We investigated immediate/late endoleaks and long-term patency following stent-graft placement for treatment of intracranial aneurysms located within the distal internal carotid artery (ICA) or vertebral artery (VA).

Methods

Forty-five aneurysms in 41 patients receiving covered stents in three centres were followed. Outcome measures included aneurysm occlusion rate, endoleaks, late in-stent stenosis rate, clinical improvement, neurological deficiencies and death.

Results

Total aneurysm exclusion was achieved in 69.2% (n?=?27), with 30.8% (n?=?12) experiencing immediate residual endoleaks. Angiographic follow-up (mean 43.5?±?14.3 months) revealed that 87.2% (n?=?34) were completely occluded with only 12.8% (n?=?5) showing residual endoleaks. Predictors of immediate endoleaks in our patient group were stent number (P?=?0.023) and stent diameter (P?=?0.022), while predictors of late endoleaks in our patient group were stent diameter (P?=?0.035) and stent angulation (P?=?0.021). Late in-stent stenosis rates were 18.0?±?13.3 and 29.0?±?18.5% compared with the period immediately following implantation at 2- and 6-year follow-ups respectively. Smoking (P?=?0.017) and stent angulation (P?=?0.020) were predictors of late in-stent stenosis.

Conclusion

Treating intracranial aneurysms with Willis stent-grafts has an acceptable immediate and late occlusion rate and long-term stented artery patency rate.

Key Points

? Covered stents can be a treatment option for intracranial aneurysms. ? Technical success for treating distal ICA and VA aneurysms can reach 97.6%. ? However immediate and late endoleaks occur in 30.8 and 12.8% respectively. ? The number, diameter and angulation of stents are possible predictors of endoleaks. ? Smoking and stent angulation seem to predict late in-stent stenosis.     

Monitoring therapeutic effects in experimental stroke by serial USPIO-enhanced MRI

Objectives

This study sought to evaluate whether the therapeutic effects of an anti-inflammatory drug such as minocycline could be monitored by serial ultrasmall superparamagnetic particles of iron oxide (USPIO)-enhanced MRI in experimental stroke.

Methods

Mice received a three-dose minocycline treatment (n?=?12) or vehicle (n?=?12) after permanent middle cerebral artery occlusion. USPIOs were administered 5?h post-surgery. MRI was performed before, 24?h and 48?h post-USPIO administration. MRI endpoints were the extent of signal abnormalities on R2 maps (=1/T2) and quantitative R2 changes over time (?R2). Post-mortem brains were prepared either for immunohistology (n?=?16) or for iron dosage (n?=?8).

Results

As expected, treatment with minocycline significantly reduced infarct size, blood-brain barrier permeability and F4/80 immunostaining for microglia/macrophages. Areas of R2 maps?>?35?ms^-1 also appeared significantly decreased in minocycline-treated mice (ANOVA for repeated measures, P?=?0.017). There was a fair correlation between these areas and the amount of iron in the brain (R²?=?0.69, P?=?0.010), but no significant difference in ?R2 was found between the two groups.

Conclusions

This study showed that the extent of signal abnormalities on R2 maps can be used as a surrogate marker to detect minocycline effects in a murine experimental model of stroke.

Key Points

? Ultrasmall superparamagnetic particles of iron oxide offer new avenues for MRI research ? Treatment of the inflammatory response following ischaemic stroke is currently undergoing evaluation. ? Minocycline treatment significantly reduced areas of signal abnormalities on USPIO-enhanced MRI. ? These areas correlated with the amount of iron in the brain. ? Thus USPIO-enhanced MRI might provide a surrogate marker to monitor treatment     

Treatment of severe osteochondral defects of the knee by combined autologous bone grafting and autologous chondrocyte implantation using fibrin gel

Purpose

Severe symptomatic and unstable osteochondral defects of the knee are difficult to treat. A variety of surgical techniques have been developed. However, the optimal surgical technique is still controversial. We present a novel technique in which autologous bone grafting is combined with gel-type autologous chondrocyte implantation (GACI).

Methods

Isolated severe osteochondral defects of the medial or lateral femoral condyle were treated by a two-step procedure. Firstly, chondrocytes were harvested during arthroscopy and cultured for 6?weeks. Secondly, a full thickness corticospongious autologuos bone graft, harvested from the medial or lateral femur condyle, is impacted in the defect and covered by GACI. The fibrin gel fills up to the exact shape of the chondral lesion and polymerizes within 3?min after application.

Results

From 2009 to 2011, 9 patients, median age 35?years (range 23–47), were treated by the combined autologous bone grafting and GACI technique. Median defect size was 7.1?cm² (range 2.5–12.0), and median depth of the lesion was 0.9?cm (range 0.8–1.2). Median follow-up was 9?months (range 6–12?months). Six patients were available for 12-month follow-up. The mean IKDC score showed a 6-month improvement from 35 (SD?±?16) to 51 (SD?±?18) (n?=?9; p?=?0.01), and a 1-year improvement from 35 (SD?±?16) to 57 (SD?±?20) (n?=?6; p?=?0.03). The mean KOOS improved from 44 (SD?±?16) to 62 (SD?±?19) (n?=?9; p?=?0.07) at 6-month follow-up and from 44 (SD?±?16) to 65 (SD?±?24) (n?=?6; p?=?0.1) at 12-month follow-up. There was one failure that needed conversion to a unicompartmental knee arthroplasty.

Conclusion

Combined autologous bone grafting and GACI may offer an alternative surgical option for severe and unstable osteochondral defects of the knee.

Level of evidence

IV.