Characterizing individual differences in children and adolescents with autism spectrum disorder: a descriptive study

Introduction

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by a higher prevalence in male than in female participants. Recent studies have hypothesized the presence of different phenotypes in male and female participants with ASD. The present study aims to assess possible sex differences in cognitive and adaptive functioning, symptomatology of ASD, and psychopathological comorbidities in a large sample of children and adolescents with ASD.

Methods

The study included a total of 2,146 children and adolescents diagnosed with ASD, comprising 1785 boys (mean age 7.12 ± 3.69 years) and 361 girls (mean age 6.25 ± 3.30 years). The age of the participants ranged from 1.35 to 19.05 years (mean age 9.98 ± 3.64). The study sought to include all children and adolescents diagnosed with Autism or ASD.

Results

Present results showed that girls with ASD had lower IQs than boys but similar adaptive functioning. The severity of symptoms of ASD was greater in boys than in girls, as were scores on psychopathological measures. With increasing age, boys with ASD showed greater impairment in social communication skills than girls and increased psychopathological comorbidities. Older girls showed fewer restricted and repetitive behaviors.

Discussion

Exploring phenotypic differences in children and adolescents with ASD fosters an understanding of subtle diagnostic facets that may go unrecognized, allowing for increasingly individualized and tailored interventions.

The development of episodic future thinking in middle childhood

The ability to imagine future events (episodic future thinking-EFT) emerges in preschoolers and further improves during middle childhood and adolescence. In the present study, we focused on the possible cognitive factors that affect EFT and its development. We assessed the ability to mentally project forward in time of a large cohort of 135 6- to 11-year-old children through a task with minimal narrative demands (the Picture Book Trip task adapted from Atance and Meltzoff in Cogn Dev 20(3):341-361. doi:10.1016/j.cogdev.2005.05.001, 2005) in order to avoid potential linguistic effects on children's performance. The results showed that this task can be used to assess the development of EFT at least until the age of 8. Furthermore, EFT scores correlated with measures of phonological short-term and verbal working memory. These results support the possibility that cognitive factors such as working memory play a key role in EFT.

Brief Report: Self-Based and Mechanical-Based Future Thinking in Children with Autism Spectrum Disorder

This brief report is a partial replication of the study by Jackson and Atance (J Dev Disabil 14:40-45, 2008) assessing nonverbal Self-based and Mechanical-based future thinking (FT) in children with Autism Spectrum Disorder (ASD). In a first step, these tasks were administered to 30 children with ASD. The two Self-based tasks were then modified as a verbal component could not be completely ruled out. Consequently, 77 children with ASD and 77 children with typical development received the modified Self-based FT tasks and the Mechanical-based FT tasks. We partially replicated the previous findings. Participants with ASD had impaired FT in both kinds of tasks and both groups performed better on tasks assessing Mechanical-based FT than Self-based FT. These results suggest that impairments of FT in ASD are not limited to Self-Projection.

Learning by observation in children with autism spectrum disorder

BACKGROUND

Observing another person performing a complex action accelerates the observer's acquisition of the same action and limits the time-consuming process of learning by trial and error. Learning by observation requires specific skills such as attending, imitating and understanding contingencies. Individuals with autism spectrum disorder (ASD) exhibit deficits in these skills.

METHOD

The performance of 20 ASD children was compared with that of a group of typically developing (TD) children matched for chronological age (CA), IQ and gender on tasks of learning of a visuomotor sequence by observation or by trial and error. Acquiring the correct sequence involved three phases: a detection phase (DP), in which participants discovered the correct sequence and learned how to perform the task; an exercise phase (EP), in which they reproduced the sequence until performance was error free; and an automatization phase (AP), in which by repeating the error-free sequence they became accurate and speedy.

RESULTS

In the DP, ASD children were impaired in detecting a sequence by trial and error only when the task was proposed as first, whereas they were as efficient as TD children in detecting a sequence by observation. In the EP, ASD children were as efficient as TD children. In the AP, ASD children were impaired in automatizing the sequence. Although the positive effect of learning by observation was evident, ASD children made a high number of imitative errors, indicating marked tendencies to hyperimitate.

CONCLUSIONS

These findings demonstrate the imitative abilities of ASD children although the presence of imitative errors indicates an impairment in the control of imitative behaviours.

Effect of Subacromial Injections of Hyaluronan on Different Grades of Rotator Cuff Lesion: A Prospective Study

Rotator cuff lesions are quite common and in some cases Hyaluronic Acid (HA) can play a role in pain relief and in restoring functions. The aim of the study was to point out the correct indications for HA injection therapy through a prospective study: firstly defining the safety and efficacy of HA in the different grades of cuff tears, then evaluating the maintenance at 90 days, as secondary endpoint. A prospective, open-label uncontrolled study was developed. One hundred patients diagnosed with different rotator cuff lesions were divided into 4 grade-related groups based on a modified Neer's classification. A cycle of 3 US-guided injections of medium-low weight HA was performed through the anterolateral way, one every two weeks. Follow-up was at 0, 15, 30, 45 and 90 days. VAS, Oxford-Shoulder-Score (OSS) and Constant-Murley were used for evaluations. In grade I and II, at day 45, a significant reduction of VAS and increase of Constant-Murley and OSS resulted. In grade IV VAS slowly decreased in the first 45 days, while OSS and Constant did not improve significantly. In grade III patients had no benefit from a clinical and subjective point of view. At ninety days the beneficial effect was still maintained in grades I, II and IV. Overall, the treatment showed a high tolerability profile. In conclusion, patients affected by bursitis or partial cuff tears benefit from HA, while in cuff arthropathy HA might only delay surgery or represent a palliative. In complete tears HA was not effective in pain relief or functional recovery.

Anemia may influence the outcome of patients undergoing neo-adjuvant treatment of rectal cancer

BACKGROUND

We hypothesized that anemia could represent one of the major factors influencing the outcome of patients undergoing neo-adjuvant treatment of rectal cancer.

PATIENTS AND METHODS

This analysis included all the consecutive patients who underwent neo-adjuvant treatment (chemotherapy and/or radiotherapy) before surgery for rectal cancer in three oncology/radiotherapy departments from June 1996 to December 2003.

RESULTS

Three hundred and seventeen patients were eligible for our analysis. Median age at diagnosis was 64 years (range 26-88 years); male/female ratio was 184/133. Two hundred and eighty-five patients (89.9%) were diagnosed with adenocarcinoma, while 32/317 (10.1%) with mucinous adenocarcinoma. Neo-adjuvant treatments carried out were as follows: radiotherapy alone in 75/317 patients (23.7%), radiotherapy plus chemotherapy in 242/317 patients (76.3%). At univariate and multivariate analysis, only the hemoglobin (Hb) level (group 1: < or=12 g/dl versus group 2: >12 g/dl) resulted in a significant factor for disease-free survival. The role of the Hb level seemed to be confirmed further by the clinical downstaging obtained in approximately 55% of patients in group 2, in comparison with 35% of the patients achieving a significant downstaging in group 1.

CONCLUSION

Our results indicated that anemia could represent an important parameter able to influence the outcome in patients receiving neo-adjuvant treatment of rectal cancer.

Epidermal growth factor receptor (EGFR) status in different stages of resected non-small cell lung cancer (NSCLC): Implications for treatment with EGFR-targeted monoclonal antibodies

20015

Background: Aim of our study was to verify potential changes in EGFR status in different stages of resected NSCLC. This was done in order to find out whether assessing the EGFR status could be considered an effective tool for planning therapy with EGFR-targeted monoclonal antibodies in different setting of patients. Methods: From January 1996 through December 2001, 439 patients underwent radical surgery for NSCLC at the Department of Thoracic Surgery of Università Politecnica delle Marche. EGFR expression was evaluated with an immunohistochemical technique on five micron-thick tissue sections obtained from specimens fixed in 10% (v/v) neutral buffered formalin and paraffin embedded.EGFR expression was detected as membranous and/or cytoplasmic brown staining of neoplastic cells with various intensity. Positivity for EGFR expression was defined as any membrane staining above background level. Both the primary and metastatic neoplasm were considered positive when ≥ 1% of the tumour cells had membranous staining. Results: Table 1 summarizes patients’ characteristics. Samples from 423 patients were available for EGFR analysis. EGFR immunohistochemical expression was found positive as follows: 15.8% in stage IIIB, 12.2% in IIIA, 2.3% in IIB, 5.3% in IIA, 4.8% in IB and 5% in IA. At multivariate analysis, EGFR status resulted indicator of prognosis both when considering all the patients and in the groups of patients with different stages of disease. Conclusions: Globally our findings seem to confirm the role of EGFR as a prognostic indicator in NSCLC. Furthermore the observation that EGFR is more frequently overexpressed in the advanced stages may suggest that EGFR-targeted treatment strategies could be more appropriated in this subgroup of patients.

[Table: see text]

No significant financial relationships to disclose.

Perioperative anemia and blood transfusions as prognostic factors in patients undergoing resection for non-small cell lung cancers

We hypothesised that anemia could represent an important prognostic factor and perioperative blood transfusions do not reduce the risk of relapse. In order to explore this topic, we assessed the correlation of preoperative anemia and blood transfusions with survival in patients with resected non-small cell lung cancer (NSCLC). Patients who underwent radical surgery for NSCLC at the Department of Thoracic Surgery of Università Politecnica delle Marche from January 1996 through December 2001, were included in our study. Four hundred and thirty-nine patients were eligible for our analysis. Survival appeared worse in patients with haemoglobin (Hb) < or =10 g/dl versus Hb >10 g/dl (p=0.012). Stratifying patients in three groups on their Hb level (group 1: Hb < or =10 g/dl; group 2: Hb=10-12 g/dl; group 3: Hb > or =12 g/dl), we observed a worse prognosis in patients with lower Hb levels, too (p=0.0325) and also in the transfused population (p=0.046). At multivariate analysis, only the age of patients, pathological stage and Hb levels resulted indicators of prognosis. Our results suggested that anemia could represent an important prognostic factor in resected NSCLC and correction of anemia in the perioperative setting does not reduce the risk of relapse.

Hepatic portal venous gas in a patient with enterovascular fistula

Hepatic portal venous gas is an uncommon clinical condition that is often characterized by acute onset of abdominal pain and is associated with a high rate of mortality despite clinical and/or surgical treatment. Radiologic diagnosis is important and usually includes abdominal radiography, ultrasound, and computed tomography. We describe the clinical, computed tomographic, and angiographic data of a patient with sigmoid diverticulitis who developed a massive embolism of the intra- and extrahepatic portal systems due to an enterovascular fistula and was treated with fistula embolization and subsequent sigmoidectomy.

Detection of crossing vessels at the ureteropelvic junction with fast MRI

OBJECTIVE

Minimally invasive surgery is an alternative to open surgery in the treatment of ureteropelvic junction obstruction (UPJO) in selected pediatric patients. Anomalous crossing vessels represent a contraindication to endopyelotomy and may also interfere with the videosurgical pyeloplasty. We investigated the usefulness of magnetic resonance imaging (MRI) without contrast in the preoperative evaluation of anomalous crossing vessels in children.

MATERIALS AND METHODS

From January 1999 to December 1999, 14 patients with diagnosis of hydronephrosis were prospectively evaluated with the aim of accurately plan the operative approach. The children underwent MRI study with HASTE sequences, heavily T2 weighted. Diagnosis was made without IV contrast material. No sedation was used.

RESULTS

4 out of the 14 patients studied were diagnosed as having anomalous crossing vessels at the ureteropelvic junction. They underwent open dismembered pyeloplasty and the diagnosis was confirmed at the operation. There was 1 false negative.

CONCLUSIONS

The fast T2 weighted MRI allows a non invasive preoperative assessment of crossing vessels at the UPJO which is of paramount importance in the choice of the appropriate surgical approach. Nevertheless, the high cost and the low sensitivity (80%, 4/5) make this technique still not routinely applicable in the preoperative work-up of children with UPJO.

Tendon involvement in rheumatoid arthritis of the wrist: MRI findings

OBJECTIVE

To evaluate the distribution and extent of wrist tendon alterations in patients with active rheumatoid arthritis (RA) using magnetic resonance imaging (MRI).

DESIGN AND PATIENTS

Forty-three clinically active RA patients with an illness duration of less than 4 years and no clinical evidence of tendons tears were enrolled in the study. There were 10 men and 33 women, with an average age of 52 years (range 33-63 years). MRI of both wrists, with one exception, was performed at 1.0 T using T1- and T2-weighted sequences (slice thickness 3 mm). Twelve healthy subjects (8 women, 4 men; mean age 31 years) were also evaluated as a control group. Two radiologists reviewed each of four schematic anatomical regions (volar, dorsal, ulnar, radial) for the degree of tendon and tendon sheath alterations using two progressive scales.

RESULTS

In the control group all tendons had homogeneous low signal intensity on all sequences. A small amount of fluid was found in six subjects but the diameter was always less than 1 mm. In the patient group minimal fluid (< 2 mm) was found in 35 (41%) wrists, grade 2 fluid (< 2 > 5 mm) in 26 (31%) and grade 3 fluid (> 5 mm) in 24 (28%). Fifty-nine (69%) of the grade 1 changes were in the volar compartment but grade 2 involvement was evenly distributed. Grade 3 changes were most common in the dorsal compartment and combined grade 2 and 3 in the dorsal and ulnar compartments were 32 (38%) and 25 (30%) compared with 16 (18%) and 17 (20%) respectively in the volar and radial compartments. The tendons were normal (grade 0) in 47 (46%) wrists. A maximum tendon signal change (grade 1) was demonstrated in 28 wrists (32%). When associated with other individual tendons grades this grade was demonstrated in the dorsal compartment in 30 (35%) wrists, in the volar compartment in 12 (14%), in the radial compartment in 17 (20%) and in the ulnar compartment in 26 (30%). A partial tear (grade 2) was detected in 7 (8%) wrists, all involving the dorsal and ulnar compartments; five underwent surgical repair and one proved to have a complete rupture of extensor digitorum. Three (3%) had a grade 3 complete tendon tear: all of these were in extensor tendons. Surgical repair was successful in one case but two ruptured again within 3 months.

CONCLUSIONS

Low grades of peritendinous effusion were more common in the volar compartment whereas moderate and high degrees of tendon sheath fluid collection and/or pannus and signs of tendonitis were more frequent in the dorsal and ulnar tendon sheaths.

Regression of multiple hepatic masses in a young patient with thalassaemia

BACKGROUND

We report a young girl with thalassaemia who showed development and regression of multiple hepatic masses.

RESULTS

The tumours, detected 3 years after allogeneic bone-marrow transplantation, showed progressive reduction in size and number following a phlebotomy program to treat iron overload.

CONCLUSION

The detailed CT, MRI and histological findings are described.

[Magnetic resonance arthrography in chronic wrist pain]

PURPOSE

To investigate the clinical role of Magnetic Resonance Arthrography (MRA) of the wrist in subjects with chronic pain.

MATERIAL AND METHODS

Thirty-five patients complaining of wrist pain for more 6 months were submitted to MRI and MRA. All patients received an intra-articular (monocompartment radiocarpal joint) injection of 2-10 mL of a 10 mmol saline solution of Gd-DPTA. Two radiologists independently evaluated the conspicuity of the intrinsic intercarpal ligaments and of the triangular fibrocartilage complex and expressed it on a 3-grade semiquantitative scale. On MRI images, complete visualization of the two structures was graded as 0, partial visualization as 1 and no visualization as 2. On MRA images, no contrast agent passage through the ligament or the complex was graded as 0, minimal passage as 1 and complete passage as 2. Sixteen patients had surgical confirmation (arthroscopy in 10 and open surgery in 6 patients).

RESULTS

On MRI images the scapholunate ligament was completely visualized in 7 patients (21%) and partially or not visualized in 28 patients (89%). MRA images showed an intact ligament in 15 cases (44%) and a partial or total tear in 20 cases (48% and 8% respectively, 56% in all). On MRI images the luno-pyramidal ligament was completely visualized in 6 patients (18%) and partially or not visualized in 29 cases (82%). On MRA images the luno-pyramidal ligament was intact in 21 cases (58%) and had a partial or total tear in 14 cases (27% and 15% respectively, 42% in all). On MRI images the triangular fibrocartilage complex was normal in 27 cases (76%) and it was only partially visualized in 8 cases (24%). On MRA images the triangular fibrocartilage complex was normal in 13 cases (37%) and had a partial injury in 22 cases (63%). There were no severe side-effects to contrast agent injection, nor severe complications. The overall diagnostic accuracy rates of MRI and MRA were 40% and 81% respectively, with sensitivity and specificity of 63% and 39% (MRI) and of 82% and 79% (MRA).

CONCLUSIONS

Compared with MRI, MRA can be considered a useful tool for the visualization of interosseous carpal ligaments and of the triangular fibrocartilage complex. MRA also helps detect injuries in these structures.

Subclinical joint involvement in psoriasis: magnetic resonance imaging and X-ray findings

Previous studies have shown that magnetic resonance imaging is more sensitive in assessing soft tissue and bone involvement in inflammatory arthritis than conventional radiography. Therefore the main objects of this study were to evaluate the frequency of hand involvement in psoriatic patients free from arthritic symptoms, and to compare the results with those of a healthy control population (age- and sex-matched). Twenty-five patients suffering from active nummular and/or plaque psoriasis with no arthritic signs or symptoms were studied together with 12 healthy control subjects. The articular structures of both hands in all patients were screened using both traditional radiological techniques and magnetic resonance imaging. Specifically, we examined: soft tissue swelling, periarticular effusion, joint effusion-synovial pannus, tendon sheath effusion, bone erosion, luxation, sub-luxation, bone cysts and subchondral signal intensity abnormalities. Sixty-eight percent of our psoriatic patients were found to be positive with at least one arthritic sign using magnetic resonance imaging, while with the standard X-ray procedure, only 32% of the same group of patients were found to be positive. Specifically, abnormal signal intensity in the subchondral focal areas were seen in 9 patients using the magnetic resonance imaging technique, while in the control group, no significant abnormalities were detected. A high percentage of psoriatic patients without apparent arthritic signs and symptoms were shown to have hand articular involvement, in particular in the distension of the capsular and periarticular oedema when examined with magnetic resonance imaging. In our experience, the use of magnetic resonance imaging allows a clear and adequate evaluation of the cartilage, bone and soft tissue material, and is diagnostically superior to X-ray in demonstrating clinically silent and radiologically invisible articular lesions. Moreover, the subchondral changes detected by magnetic resonance imaging were unexpected findings which could imply an ischaemic origin.

Dynamic MRI of the breast

OBJECTIVE

To describe the rationale, the technical requirements and the examination technique of dynamic magnetic resonance studies of the breast and to assess the role of this method in the clinical diagnostic protocol.

MATERIAL AND METHODS

We reviewed the relative literature and compared the results with our personal experience.

RESULTS

The earliest reports on the possibility of differentiating carcinoma from benign tissue with magnetic resonance imaging came from Germany, where in 1986 Heywang and coworkers used T1-weighted spin-echo sequences before and after i.v. Gd-DTPA administration with an imaging time of approximately 5 mins and 5 mm slice thickness. With advances in magnetic resonance technology, Heywang Koebrunner adopted a static three-dimensional fast low-angle shot technique permitting < 3 mins' imaging time and providing high resolution with thin slices. This approach may detect even the carcinoma which occasionally does not enhance in the typical rapid, intense way. A review of 400 biopsy-proved lesions showed that all carcinomas enhanced strongly, all but 5% rapidly and 85% focally. Over 70% of benign masses exhibited no major contrast uptake, although some benign tumors and proliferative dysplasias enhanced strongly. At present, Heywang-Koebrunner use rapid three-dimensional gradient-echo sequences (TR/TE 14/7, FA 25 degrees; at 1.0 T) which have the advantages of three-dimensional imaging and permit dynamic studies (< 1 min/sequence). The same sequence is used at our institution. The dynamic technique is advocated by Kaiser who in 1989 reported preliminary sensistivity and specificity values over 95%. The time/signal intensity curves revealed the rapid and strong enhancement of malignancies, the gradual and strong enhancement of the only fibroadenoma studied, and the gradual and mild contrast uptake of benign dysplasia. In 1992, in nearly 1000 dynamic examinations, Kaiser and Reiser reported 98.3% sensitivity, 97.0% specificity, 82.1% predictive value and 97.2% accuracy. The combination of rapid acquisition with techniques that preserve high spatial resolution may improve specificity by allowing the study of lesion morphology as well as of enhancement patterns. A whole-breast imaging technique has been reported which permits acquisition times < 15 s by partial sampling of the central k-space region superimposed on high-resolution three-dimensional images.

CONCLUSIONS

Dynamic magnetic resonance imaging of the breast is currently an important step of the clinical protocol of breast diseases, but there is no established study protocol yet.

Rheumatoid arthritis: follow-up and response to treatment

OBJECTIVE

To assess the role of diagnostic imaging techniques in the identification and follow-up of the anatomical damage induced by the chronic inflammatory process of rheumatoid arthritis (RA) not only to study the natural history of the disease but also and especially to assess the long-term response to disease-modifying anti-rheumatic drugs (DMARD).

MATERIALS AND METHODS

The relative literature data were reviewed and compared with our personal experience with different imaging modalities such as conventional radiography (CR), ultrasound (US) and magnetic resonance imaging (MRI).

RESULTS

Several radiologic techniques have been used over the years to study articular damage in RA: they describe and quantify the articular damage (semi-quantitative analysis) based on a series of parameters and elementary anatomical lesions which are given a rising score. For its sensitivity in detecting early disease signs and the possibility to express anatomical damage progression quantitatively, Sharp's index is considered the best tool for evaluating RA patients. The close correlation between clinical parameters and the radiologic scores obtained regardless of the method applied led to a new concept of anatomical damage related to the 'radiologic progression of the disease' which is a more precise measure of RA severity than the single isolated radiograph. The progression of radiologic damage in rheumatoid arthritis is expressed as the number or proportion of new eroded joints/year: independent of the index adopted and the terms used to express progression, severe radiologic damage occurs in the early disease stage, involving approximately 2% of the joints within about 1 year, and 13% within 2 years, with an estimated average annual progression of 1.3%. Radiologic techniques evaluate the anatomical damage in the course of RA only with reference to the osseous component of the joint and therefore apply to a disease stage that is largely irreversible. MRI and US detect the soft-tissue damage occurring in the earlier phases and are more likely to respond to early treatment. The former technique appears to be useful to detect soft-tissue damage like synovial pannus, intra- and periarticular and peritendinous effusion, capsuloligamentous articular and tendon changes. Its high sensitivity for minimal bone erosions and chondromalacia has been demonstrated. US allows to demonstrate a wide range of soft-tissue changes of the hand and wrist. Joint-cavity widening, loss of cartilage definition, bone erosions, widening of flexor tendon sheath and tendon structure are also well depicted on ultrasound images.

CONCLUSIONS

CR is the central tool in the diagnosis, staging and follow-up of RA patients and in general in the assessment of treatment efficacy; MRI and US are complementary tools.

Limitations of magnetic resonance imaging in measurement of hepatic iron

To evaluate the usefulness of magnetic resonance imaging for the quantitative determination of hepatic iron, we examined 43 patients with thalassemia major and assessed the influence of pathologic changes in the liver on the precision of estimates of the hepatic iron concentration. Tissue signal intensities were measured from magnetic resonance T1-weighted images derived from gradient-echo (GE) pulse sequences and the ratio of the signal intensity of liver to muscle calculated. By excluding patients (n = 9) having a signal intensity ratio (SIR) less than or equal to 0.2, a linear relationship with hepatic iron was found and subsequent analyses were limited to these 34 patients. In 27 patients with hepatic fibrosis, an overall correlation of -0.848 was found between hepatic iron and SIR. By contrast, in the seven patients with no fibrosis, the correlation coefficient (-0.993) was significantly greater (P < .0001). Despite the differences in correlation, the regression line between hepatic iron and SIR for the patients with no fibrosis did not differ significantly with respect to either slope or intercept from that of the patients with fibrosis. Thus, the presence of fibrosis did not seem to affect the pattern of the relationship between hepatic iron and the SIR, but rather to increase the variability of the relationship. Clinically, the presence of fibrosis makes estimates of hepatic iron derived from magnetic resonance imaging so variable as to be of little practical use in the management of transfusional iron overload.

[Acute knee block. Assessment with magnetic resonance, correlated with arthroscopy]

Posttraumatic acute articular blocks of the knee may be caused by "mechanical" factors, such as the interposition of some osteochondral, meniscal or ligamentous fragments between condyles and tibial plateau or by non-mechanical ("functional") factors, such as the pain associated with capsular-ligamentous structure injuries or with intraosseous bruises involving the synovia. From January, 1994, to January, 1996, we examined 751 patients for posttraumatic knee injuries. The patients were submitted to MRI with a dedicated unit and we selected 86 of them who had an acute articular block as the major symptom. The block had a mechanical cause in 36 patients of the selected group (41.8%), as confirmed at arthroscopy, while the other 50 patients (58.2%) had a functional block. Fifteen of the latter patients had only intraosseous bruising, with no ligament or meniscus damage, while the other 35 had isolated or variously associated menisco-ligamentous injuries, as confirmed at arthroscopy. All the patients also had some intraosseous bruises which were clearly depicted at MRI. This study demonstrates that MRI is an extremely valuable tool in assessing the cause of articular blocks, allowing a prompt appropriate choice to be made between therapeutic arthroscopy and weight-free limb immobilization.

MRI in characterization of focal liver lesions: comparison of T2 weighting by conventional spin-echo and turbo spin-echo sequences

Forty-one patients with 61 proved focal liver lesions underwent MRI of the liver at 1.0 T, with the aim of evaluating the usefulness of turbo spin-echo (TSE) sequences in characterizing focal liver lesions, by comparing them with conventional spin-echo (CSE) sequences. Two different TSE protocols were employed. with constant echo time and varying repetition time: TSE-S (3000 msec) and TSE-L (5100 msec). All images were evaluated quantitatively (signal-to-noise ration 'SNR') and qualitatively: because benign lesions were all liquid (12 cysts and 10 hemangiomas), they were well characterized morphologically on the basis of signal intensity. Mean SNR was significantly different between metastases and benign lesions (P < .0001) with all T2 sequences. Among the single T2 sequences tested, logistic regression analysis showed TSE-L to have the best predictive ability of the nature of focal lesions, with a G value of 42.02, compared to 29.87 of TSE-S and 25.55 of CSE second echo (SE II). The combination of TSE-L with TSE-S did not modify these results, whereas the combination of TSE-L with CSE only resulted in slight improvement (G = 46.95). Comparison of the receiver operating characteristic (ROC) curves showed only SE II (area under the ROC curve of .8312) to be significantly inferior to the best single sequence, or TSE-L (area under the ROC curve of .9176; P = .027). All sequences were equivalent in qualitative evaluation with good reproducibility, sensitivity ranging from .94 to 1.0 and specificity ranging from .86 to .93. This study confirms the value of TSE sequences in characterization of focal liver lesions. Time of acquisition is strongly reduced with these sequences, whereas results are fairly similar to those obtained with CSE. TSE sequences could therefore replace CSE for the study of focal liver lesions.

[Magnetic resonance arthrography in chondral disease of the knee]

The clinical usefulness of Magnetic Resonance Imaging (MRI) of the knee in the depiction of meniscal, ligament and tendon lesions is well known. In contrast, the role MRI plays in the diagnosis of chondromalacia remains debated, the gold standard being arthroscopy. A new technique, i.e., MR arthrography (MRA), has been recently proposed which consists of the intraarticular injection of a paramagnetic contrast agent (Gd-DTPA) during MRI. Thirty-one patients with clinically suspected chondromalacia of the knee were examined with MRA. The exams were performed with a 1T superconductive magnet and a dedicated coil. All the patients were examined before (baseline scans) and after paramagnetic contrast agent injection. MRA results were compared with arthrographic findings. Baseline MRI had 25% sensitivity, 77.9% specificity and 83% diagnostic confidence in the diagnosis of chondromalacia; these figures increased to 93%, 97.6% and 91.5% after contrast agent injection. This preliminary experience confirms MRA to be a useful tool in the diagnosis of chondral knee conditions.