BSKs are partially redundant positive regulators of brassinosteroid signaling in Arabidopsis

Arabidopsis thaliana brassinosteroid signaling kinases (BSKs) constitute a receptor-like cytoplasmic kinase sub-family (RLCK-XII) with 12 members. Previous analysis demonstrated a positive role for BSK1 and BSK3 in the initial steps of brassinosteroid (BR) signal transduction. To investigate the function of BSKs in plant growth and BR signaling, we characterized T-DNA insertion lines for eight BSK genes (BSK1-BSK8) and multiple mutant combinations. Simultaneous elimination of three BSK genes caused alterations in growth and the BR response, and the most severe phenotypes were observed in the bsk3,4,7,8 quadruple and bsk3,4,6,7,8 pentuple mutants, which displayed reduced rosette size, leaf curling and enhanced leaf inclination. In addition, upon treatment with 24-epibrassinolide, these mutants showed reduced hypocotyl elongation, enhanced root growth and alteration in the expression of BR-responsive genes. Some mutant combinations also showed antagonistic interactions. In support of a redundant function in BR signaling, multiple BSKs interacted in vivo with the BR receptor BRI1, and served as its phosphorylation substrates in vitro. The BIN2 and BIL2 GSK3-like kinases, which are negative regulators of BR signaling, interacted in vivo with BSKs and phosphorylated them in vitro, probably at different sites to BRI1. This study demonstrates redundant biological functions for BSKs, and suggests the existence of a regulatory link between BSKs and GSK3-like kinases.

Co-ordinated regulation of flowering time, plant architecture and growth by FASCICULATE: the pepper orthologue of SELF PRUNING

Wild peppers (Capsicum spp.) are either annual or perennial in their native habitat and their shoot architecture is dictated by their sympodial growth habit. To study shoot architecture in pepper, sympodial development is described in wild type and in the classical recessive fasciculate (fa) mutation. The basic sympodial unit in wild-type pepper comprises two leaves and a single terminal flower. fasciculate plants are characterized by the formation of floral clusters separated by short internodes and miniature leaves and by early flowering. Developmental analysis of these clusters revealed shorter sympodial units and, often, precocious termination prior to sympodial leaf formation. fa was mapped to pepper chromosome 6, in a region corresponding to the tomato SELF-PRUNING (SP) locus, the homologue of TFL1 of Arabidopsis. Sequence comparison between wild-type and fa plants revealed a duplication of the second exon in the mutants' orthologue of SP, leading to the formation of a premature stop codon. Ectopic expression of FASCICULATE complemented the Arabidopsis tfl1 mutant plants and as expected, stimulated late flowering. In agreement with the major effect of FASCICULATE imposed on sympodial development, the gene transcripts were localized to the centre of sympodial shoots but could not be detected in the primary shoot. The wide range of pleiotropic effects on plant architecture mediated by a single 'flowering' gene, suggests that it is used to co-ordinate many developmental events, and thus may underlie some of the widespread variation in the Solanaceae shoot architecture.

Timing of testicular sperm retrieval procedures and in vitro fertilization-intracytoplasmic sperm injection outcome

OBJECTIVE

To compare the outcome of IVF-intracytoplasmic sperm injection (ICSI) using testicular spermatozoa obtained on the day of ovum pick-up (OPU) or on the day before OPU.

DESIGN

Retrospective study.

SETTING

An IVF clinic in a university hospital.

PATIENT(S)

Forty-seven IVF-ICSI cycles using testicular spermatozoa in 28 couples with the male partner suffering from nonobstructive azoospermia.

INTERVENTION(S)

Sperm retrieval was performed either on the OPU day (23 cycles in 19 patients; group A) or on the day before OPU (24 cycles in 15 patients; group B). Testicular sperm aspiration (TESA) was performed and followed by testicular sperm extraction (TESE) if no spermatozoa could be found.

MAIN OUTCOME MEASURE(S)

The presence of motile spermatozoa at the time of ICSI and fertilization and clinical pregnancy rates.

RESULT(S)

A similar proportion of motile spermatozoa (60.9% vs. 62.5%), fertilization rate (61.7% vs. 58.9%), and clinical pregnancy rate per transfer (34.8% and 29.2%) were obtained for groups A and B, respectively.

CONCLUSION(S)

Testicular sperm retrieval can be performed on the day before OPU without compromising success. Considerable medical and practical advantages may be offered by further advancement of testicular sperm retrieval procedures to 48 hours before OPU. This approach should thus be further evaluated.

Reduction of exercise-induced asthma oxidative stress by lycopene, a natural antioxidant

BACKGROUND

Lycopene has previously been shown to have high antioxidative activity. In view of the controversy regarding the beneficial effect of antioxidants on asthma, the acute effects of lycopene (LYC-O-MATO) on airway hyperreactivity were assessed in patients with exercise-induced asthma (EIA).

METHODS

Twenty patients with EIA participated in our study to verify the antioxidative effects. The test was based on the following sequence: measurement of baseline pulmonary function, 7-min exercise session on a motorized treadmill, 8-min rest and again measurement of pulmonary function, 1-week, oral, randomly administered, double-blind supplementation of placebo or 30 mg/day of lycopene (LYC-O-MATO), measurement of pulmonary function at rest, 7-min exercise session, and 8-min rest and again measurement of pulmonary function. A 4-week washout interval was allowed between each protocol.

RESULTS

All patients given placebo showed significant postexercise reduction of more than 15% in their forced expiratory volume in 1 s (FEV1). After receiving a daily dose of 30 mg of lycopene for 1 week, 11 (55%) patients were significantly protected against EIA. Serum analyses of the patients by high-pressure liquid chromatography detected in the lycopene-supplemented patients an elevated level of lycopene compared to the placebo group, with no change in retinol, tocopherols, or in the other carotenoids.

CONCLUSIONS

Our results indicate that a daily dose of lycopene exerts a protective effect against EIA in some patients, most probably through an in vivo antioxidative effect.

Poor outcome with round spermatid injection in azoospermic patients with maturation arrest

OBJECTIVE

To compare the outcome of intracytoplasmic sperm injection (ICSI) and round spermatid injection (ROSI), both obtained by testicular sperm extraction (TESE), and to compare the results of fresh versus frozen ROSI.

DESIGN

Retrospective study.

SETTING

An IVF unit at a university hospitalPatient(s): Eighteen infertile couples with nonobstructive azoospermia.

INTERVENTION(S)

TESE with ROSI or ICSI of mature spermatozoa into metaphase II oocytes was performed. The resulting embryos were transferred to female partners. The spare round spermatids were frozen.

MAIN OUTCOME MEASURE(S)

Fertilization and cleavage rates, embryo quality, and clinical pregnancy rates.

RESULT(S)

Seventeen ROSI cycles and six ICSI cycles were compared. Fertilization rate following ROSI (44.9%) was significantly lower than with ICSI (69%). A significantly higher rate of cleavage arrest occurred following ROSI (40.8%) as compared to ICSI (8.2%). The morphology of embryos resulting from ROSI was significantly poorer. No pregnancies were achieved following ROSI as compared to a 50% clinical pregnancy rate in the ICSI group. The fertilization and cleavage rates following ROSI with fresh versus frozen-thawed spermatids were comparable.

CONCLUSION(S)

In azoospermic patients with maturation arrest at the stage of round spermatids the efficiency of ROSI appears to be extremely poor. The role of ROSI in the treatment of nonobstructive azoospermia should be reevaluated.

Zygote intrafallopian transfer in patients with tubal factor infertility after repeated failure of implantation with in vitro fertilization-embryo transfer

OBJECTIVE

To evaluate the efficacy of zygote intrafallopian transfer (ZIFT) in terms of implantation and pregnancy rates in patients with tubal factor infertility and repeated implantation failure in IVF-ET cycles.

DESIGN

Retrospective analysis of ZIFT cycles.

SETTING

An IVF unit in a university hospital.

PATIENT(S)

Criteria for patient selection for ZIFT included at least four failures of implantation in IVF-ET cycles in which at least 3 embryos were replaced per transfer and a cause of infertility diagnosed as male, unexplained, or tubal factor with proof of one patient tube.

INTERVENTION(S)

Four to six zygotes were transferred by laparoscopy into the fallopian tube 24-26 hours after oocyte retrieval.

MAIN OUTCOME MEASURE(S)

Implantation and pregnancy rates were determined in 112 ZIFT cycles performed in 81 patients with repeated failure of implantation. Results were further stratified for patients with tubal factor (n = 15) and patients without tubal factor (n = 66).

RESULT(S)

The pregnancy and implantation rates for all ZIFT cycles were 35.1% and 11.1%, respectively. Pregnancy and implantation rates per cycle in patients with tubal factor versus patients without tubal factor were 26.6% versus 37.1% and 9.4% versus 11.4%, respectively.

CONCLUSION(S)

ZIFT can be considered as a mode of treatment for patients with repeated failure of implantation in IVF-ET and with tubal factor with proved patency of one tube.

Estradiol supplementation during the luteal phase may improve the pregnancy rate in patients undergoing in vitro fertilization-embryo transfer cycles

OBJECTIVE

To evaluate the effect of adding E(2) to progestin supplementation during the luteal phase on pregnancy and implantation rates in patients undergoing IVF cycles.

DESIGN

Prospective, randomized study.

SETTING

An IVF unit in a university hospital.

PATIENT(S)

Patients who were undergoing IVF with controlled ovarian hyperstimulation using a GnRH analog and who had E(2)2,500 pg/dL at the time of hCG administration.

INTERVENTION(S)

Serum concentrations of E(2) and progesterone were measured in all patients on days 7, 10, and 12 after ET.

MAIN OUTCOME MEASURE(S)

The E(2) and progesterone profiles of the luteal phase and the pregnancy and implantation rates were documented. Data were analyzed for the entire study population and further stratified according to the GnRH analog protocol used (short or long).

RESULT(S)

Significantly higher E(2) levels were found during the luteal phase in the group that received E(2) supplementation. This effect was more pronounced in the patients who were treated with the long GnRH analog protocol. Significantly higher pregnancy and implantation rates were recorded in the patients who received E(2) supplementation and were treated with the long GnRH analog protocol.

CONCLUSION(S)

For patients who are treated with the long GnRH analog protocol for controlled ovarian hyperstimulation and for whom luteal support with hCG is contraindicated, the addition of E(2) to the progestin support regimen may have a beneficial effect on pregnancy and implantation rates.

Prevention of exercise-induced asthma by a natural isomer mixture of beta-carotene

BACKGROUND

The unicellular alga Dunaliella bardawil was previously shown to contain very high concentrations of beta-carotene composed of equal amounts of the all-trans and 9-cis stereoisomers which differ in their physicochemical features and antioxidative activity. Due to the controversy regarding the beneficial effect of antioxidants on asthma, the acute effects of beta-carotene of Dunaliella was assessed on airway hyperreactivity in patients with exercise-induced asthma (EIA).

METHODS

Thirty-eight patients with EIA participated in our study to verify the antioxidative effect. The test was based on the following sequence: baseline pulmonary function, 7 minutes exercise session on a motorized treadmill, 8 minutes rest, 1-week oral random, double-blind supplementation of placebo or 64 mg/day beta-carotene, pulmonary functions at rest, 7 minutes exercise session, 8 minutes rest and again pulmonary functions.

RESULTS

All patients given placebo showed a significant postexercise reduction of more than 15% in their forced expiratory volume in one second (FEV1). Of the 38 patients who received a daily dose of 64 mg of beta-carotene for 1 week, 20 (53%) were protected against EIA.

CONCLUSIONS

Our results indicate that a daily dose of Dunaliella beta-carotene exerts a protective effect against EIA in some patients most probably through in vivo antioxidative effect.

Incubation with sperm enhances in vitro maturation of the oocyte from the germinal vesicle to the M2 stage

OBJECTIVE

To evaluate the effect of sperm in the culture medium on the rate of oocyte maturation in vitro from the germinal vesicle to the M2 stage.

DESIGN

Prospective randomized controlled study.

SETTING

The IVF Unit, Wolfson Medical Center, Holon, Israel.

PATIENT(S)

All women in whom oocytes were retrieved at the germinal vesicle stage between December 1995 and March 1996.

INTERVENTION(S)

Oocytes retrieved at the germinal vesicle stage were divided prospectively and randomly into four groups of incubation conditions: group 1, intact germinal vesicle with cumulus; group 2, intact germinal vesicle with sperm cells in the culture medium; group 3, stripped germinal vesicle; and group 4, stripped germinal vesicle with sperm cells. Oocytes were observed 24 hours after retrieval, and the stage of maturation was recorded. Oocytes that reached the M2 stage underwent the intracytoplasmic injection procedure, and the fertilization rate in each group was recorded at 48 hours.

MAIN OUTCOME MEASURE(S)

Maturation rate from the germinal vesicle to M2 stage and fertilization rate.

RESULT(S)

Each group contained 20 germinal vesicle oocytes. In groups 1 and 2, 2 (10%) and 9 (45%) oocytes, respectively, reached the M2 stage at 24 hours; at 48 hours, 1 (5%) and 8 (40%) embryos developed, respectively. The results in group 2 were significantly higher than in group 1. In groups 3 and 4, 6 (30%) and 16 (80%) oocytes, respectively, reached the M2 stage at 24 hours; at 48 hours, 5 (25%) and 14 (70%) embryos developed, respectively. Results in group 4 were significantly higher than those in groups 1, 2, and 3.

CONCLUSION(S)

Both methods of oocyte activation (i.e., addition of sperm to the culture medium or removal of the cumulus) enhance oocyte maturation in vitro, but the sperm-incubation method has a more pronounced effect. A combination of both methods leads to an exceptionally high rate of oocyte maturation, followed by a high fertilization rate.

Disappearance of liver cell adenoma: CT and MR imaging

We report the disappearance of liver cell adenoma, documented by computed tomography (CT) and magnetic resonance (MR) imaging. A 42-year-old woman with a diagnosis of hepatic adenoma was followed up by CT and MR imaging after cessation of oral contraceptive use. At the time of diagnosis, the adenoma was 4 cm in diameter and appeared hypervascular on CT. At MR imaging, the lesion was hypointense on T1-weighted sequences, and hyperintense on T2-weighted sequences. The lesion disappeared 4 years after cessation of oral contraceptive use. We conclude that in nonoperated patients CT scans and MR imaging are useful for following the evolution, and documenting the regression, of liver cell adenomas.

Blocking effect of vitamin C in exercise-induced asthma

OBJECTIVE

To determine if vitamin C (ascorbic acid) has a protective effect on the hyperreactive airways of patients with exercise-induced asthma (EIA).

DESIGN

All the patients underwent pulmonary function tests at rest, before and 1 hour after receiving 2 g of oral ascorbic acid. They were then randomly assigned in a double-blind manner to receive 2 g of ascorbic acid or a placebo 1 hour before a 7-minute exercise session on a treadmill. Pulmonary function tests were performed after an 8-minute rest. This procedure was repeated 1 week later, with each patient receiving the alternative medication.

SETTING

A university hospital.

PARTICIPANTS

Twenty patients with asthma (13 males and 7 females), with ages ranging from 7 to 28 years (mean, 13.8 years). All patients who had a decline of at least 15% in their forced expiratory volume in 1 second after a standard exercise test on a motorized treadmill received a diagnosis of EIA. MAIN-OUTCOME MEASURES: All patients were advised to stop using their regular asthma medication or bronchodilator 12 hours before the test. Pulmonary function tests were performed in the same ambient conditions on all patients.

RESULTS

All patients received a diagnosis of EIA. Ascorbic acid administration did not change the results of pulmonary functions at rest after 1 hour. In 9 patients, a protective effect on exercise-induced hyperreactive airways was documented. Four of 5 patients who received ascorbic acid and documented a protective effect on EIA continued to receive ascorbic acid, 0.5 g/d, for 2 more weeks with the same protective effect.

CONCLUSIONS

The efficacy of vitamin C in preventing EIA cannot be predicted. However, vitamin C may have a protective effect on airway hyperreactivity in some patients with EIA.

[Imaging of peripheral cholangiocarcinoma. Comparison with pathological anatomy]

OBJECTIVE

Peripheral cholangiocarcinoma is a rare malignant intrahepatic tumor which originates in the distal bile duct. Our purpose was to identify the imaging characteristics of peripheral cholangiocarcinoma and to establish a correlation with surgical and histopathologic findings.

METHODS AND MATERIALS

The imaging data of 16 patients with proven cholangiocarcinoma were retrospectively reviewed by sonography in 13 cases, computed tomography in 13 cases, magnetic resonance imaging in 6 cases, and angiography in 10 cases and correlated with surgical and histopathologic findings.

RESULTS

In most cases peripheral cholangiocarcinoma appeared as a single, large (> 10 cm), heterogeneous, and non encapsulated mass. On precontrast computed tomography, the lesions were mostly low density. Enhancement was moderate in the bolus phase and increased in the delayed scan. With magnetic resonance imaging, lesion signals were low intensity in T1-weighted images and variable intensity in T2-weighted images. On angiogram, lesions were often hypovascular. Associated features were frequently observed: portal encasement (69%), lobar atrophy or capsular retraction (43%), dilated intrahepatic bile ducts (30%), extension into the hepatic capsule (23%), and inferior vena cava extension (15%). Radiopathologic comparison showed that imaging modalities accurately identified vascular encasement, but underestimated extrahepatic tumor extension.

CONCLUSION

In most cases, peripheral cholangiocarcinoma has a typical appearance which may be helpful in differentiating this disease from other intrahepatic tumors.

Inflammatory pseudotumor of the liver: radiologic-pathologic correlation

OBJECTIVE

To report the imaging appearance of inflammatory pseudotumor of the liver with pathologic correlation in three cases.

MATERIALS AND METHODS

Sonography and CT were performed in all cases. Two lesions were evaluated with MRI. All lesions were resected, and imaging data and histopathology were correlated.

RESULTS

In all three cases ultrasonography revealed a hypoechoic well-circumscribed mass. In one case CT showed a hypodense homogeneous lesion with central calcifications. No enhancement was demonstrated on postcontrast CT. The lesion appeared hypointense relative to the adjacent liver on T1-weighted MRI and isointense on T2-weighted MRI. A perilesional rim was detected in all cases on postcontract CT and/or MRI. This rim correlated with the histopathologic demonstration of a fibrous capsule in all three cases.

CONCLUSION

The following features may be encountered in inflammatory pseudotumor: a homogeneous avascular appearance on CT, isointense signal on T2-weighted MRI, and the presence of a capsule. All these findings correlated well with histopathologic findings.

Hepatic adenoma: MR findings in 51 pathologically proved lesions

PURPOSE

To describe the magnetic resonance (MR) imaging features of hepatic adenoma and correlate these findings with histopathologic findings.

MATERIALS AND METHODS

MR findings of 51 pathologically proved hepatic adenomas in 29 consecutive patients were retrospectively analyzed. T1- and T2-weighted spin-echo (SE) images were obtained in all patients, and contrast material-enhanced MR images were obtained in 16 patients.

RESULTS

At pathologic analysis, a peripheral rim, observed in 16 (31%) hepatic adenomas, corresponded to pseudocapsule, and tumor heterogeneity, observed in 26 (51%) lesions, corresponded to hemorrhagic necrosis and peliosis. Hyperintensity on T1-weighted SE images was observed in 30 (59%) adenomas; 10 (67%) of 15 hepatic adenomas were hyperintense on contrast-enhanced gradient-echo images, and 13 (45%) of 29 were hyperintense on delayed contrast-enhanced T1-weighted SE images.

CONCLUSION

Presence of a peripheral rim, heterogeneity, and hyperintensity are common features of hepatic adenoma.

Association of multiple liver cell adenomas with spontaneous intrahepatic portohepatic shunt

The association of multiple liver cell adenomas containing foci of focal nodular hyperplasia with a spontaneous intrahepatic portohepatic venous shunt is reported in a 13-year-old male patient. At least eight nodules less than 10 cm in diameter were recognized and proved by means of surgical resection or surgical biopsies. These lesions were heterogeneous and hypodense on precontrast computed tomographic (CT) scans, and were slightly enhanced after injection of contrast medium. At magnetic resonance (MR) imaging, the signal intensity of these nodules varied. It was either hyperintense or hypointense on T1-weighted SE images. Sonography and angiography demonstrated a portohepatic venous shunt and hepatic arterialization was observed. These findings emphasize the hypothesis that hepatic arterialization may cause the development of liver cell adenomas. Moreover, it is suggested that liver cell adenoma and focal nodular hyperplasia have a common pathogenesis.

Nontumorous attenuation changes on CT arterial portography

OBJECTIVE

We prospectively studied the frequency and the distribution of nontumorous attenuation changes during CT arterial portography.

MATERIALS AND METHODS

Computed tomography arterial portograms were obtained in 67 consecutive patients. The frequency and distribution of nontumorous attenuation changes (pseudolesions, areas of hypo- or hyperperfusion) were analyzed and related to the size of the tumor, the vascular status assessed by Doppler examination, and the presence of chronic liver disease.

RESULTS

Pseudolesions were detected in 19 patients (28%). They were typical in 13 cases and atypical (round shaped or located in the caudate or right lobe) in 6. Segmental, lobar, or diffuse perfusion defects were seen in 36 patients (54%). In 56% of the cases, they were adjacent to large tumors and related to compression or thrombosis of intrahepatic portal branches as demonstrated by sonographic and Doppler findings. Areas of hyperperfusion were detected in 14 patients (21%). Of these cases, eight (57%) were peritumoral hyperperfusion. In all cases, the mean diameter of the tumors was large and there was compression of adjacent hepatic vein as demonstrated by sonographic and Doppler findings.

CONCLUSION

Nontumorous attenuation changes are common in CT arterial portography. Factors leading to these artifacts include size of the tumor and vascular consequences of the tumor. Sonographic and Doppler studies may play a role in predicting these factors.

Cine MRI of mitral regurgitation in planes angled along the intrinsic cardiac axes

OBJECTIVE

This prospective study was designed to evaluate the mechanism and severity of mitral regurgitation (MRG) by means of cine MRI using planes angled along the intrinsic cardiac axes.

MATERIALS AND METHODS

In 25 patients with MRG, analysis of the direction, extent, and distribution of left atrial signal void area was performed on both two chamber and four chamber cine MRI views. Cine MRI features including qualitative grading, maximal length of regurgitant jet, and ratio of regurgitant jet area to left atrial area were compared with the results of color flow Doppler (CFD) mapping (n = 25), angiography (n = 20), and regurgitant fraction as determined at catheterization (n = 15).

RESULTS

In the four chamber view, cine MRI demonstrated central extension of regurgitant jet (n = 8) in cases with dilatation of valve annulus or retraction of both mitral valve leaflets, anterior extension (n = 8) in cases with prolapse of the posterior leaflet, and posterior extension (n = 7) in cases with prolapse of the anterior leaflet or retraction of the posterior leaflet. In two cases of mild MRG with small signal void area, evaluation of mechanism was not feasible. The results of cine MRI and angiographic qualitative gradings were the same in 19 of the 20 patients and differed by one grade in the other patient. In the 25 patients, maximal length of the regurgitant jet was well correlated with both regurgitant jet area and ratio of the jet area to the left atrial area as determined by CFD mapping (r = 0.91, r = 0.85, p < 0.0001, respectively). In 15 patients the maximal length of regurgitant jet was correctly correlated with regurgitant fraction determined at catheterization (r = 0.76, p < 0.001).

CONCLUSION

Cine MRI by means of planes angled along the intrinsic cardiac axes allows assessment of both the mechanism and the severity of MRG.

Open window thoracostomy, myoplasty, and epiploplasty for treatment of postpneumonectomy empyema: CT evaluation

PURPOSE

To demonstrate the computed tomographic (CT) appearance of the postpneumonectomy space (PPS) after surgical treatment of postpneumonectomy empyema.

MATERIALS AND METHODS

The authors retrospectively reviewed 22 CT scans obtained in 15 patients after open window thoracostomy (OWT) (n = 4), myoplasty (n = 12), and epiploplasty (n = 1).

RESULTS

After uncomplicated OWT, the retracted PPS contained air and/or gauze without residual pleural fluid. After uncomplicated myoplasty, marked retraction of the operated hemithorax was observed. CT allowed localization of transposed muscle flaps and fatty tissue within the PPS. A moderate amount of fluid and air was present during the 1st month after surgery. After uncomplicated epiploplasty, the retracted PPS contained homogeneous tissue with characteristic fatty attenuation. Complications including recurrent empyema, recurrent bronchopleural fistula, aseptic fluid collection, necrosis and fatty transformation of muscle flaps, and tumor recurrence were accurately demonstrated.

CONCLUSION

CT is useful in follow-up after surgical treatment of postpneumonectomy empyema because it permits accurate evaluation of the PPS.

[Radiological exploration of the thorax. Strategy and indications]

The widespread use of computed tomography and the advent of magnetic resonance imagery have considerably modified the methods and strategies of thoracic exploration over the last 10 years. Standard radiography remains the first-line examination for all thoracic diseases, and often is the only imagery required; further explorations are indicated on the basis of the information seen on standard films. Computed tomography has become an essential element in the work-up of all diseases involving a tumoural process in the lung. It is also indicated in bronchiestasis and for the exploration of chronic lung diseases. Further information may be obtained with magnetic resonance imagery. Although this method cannot be used to explore the pulmonary parenchyma, it is particularly adapted in cases involving the pleura, mediastinum (tumours and vessels) and the thoracic wall. Scintigraphy is mainly used to detect pulmonary migrations and to investigate lung function before thoracic surgery. Pulmonary angiography remains the reference imagery for the diagnosis of pulmonary embolism but has lost its other indications. Tomobronchography is exceptionally required. Current strategy in infectious diseases is to always begin with standard radiography, then to complete the work-up with further examinations only when necessary. Correct evaluation of tumoural processes relies heavily on tomography even for very small masses since it provides essential information on localization and extension. Management of primary bronchogenic cancers also requires repeated tomographic studies. Magnetic resonance images are indicated on the basis of the tomography results and are particularly useful in tumours of the apex and extension to the spinal column or mediastinum. For chronic bronchopathy, pulmonary scintigraphy is performed after standard films in the preoperative work-up then is sometimes completed with other techniques. In cases of suspected pulmonary emboli, a normal scintigraphy can eliminate the diagnosis. Inversely, certain teams propose coupling perfusion scintigraphy with ventilation scintigraphy to detect mismatches, particularly distinctive signs of pulmonary emboli. When the diagnosis remains uncertain, pulmonary angiography is the reference imagery technique.

MRI and cine MRI of asymmetric septal hypertrophic cardiomyopathy

OBJECTIVE

This study was designed to determine MR and cine MR characteristics of asymmetric septal hypertrophic cardiomyopathy and to correlate MR and cine MR features with the severity of left ventricular outflow tract obstruction.

MATERIALS AND METHODS

Ten consecutive patients with asymmetric septal hypertrophic cardiomyopathy [resting obstructive (n = 3), latent obstructive (n = 4), nonobstructive hypertrophic (n = 3)] and five healthy volunteers underwent MRI and cine MRI. Oblique two chamber and four chamber views were obtained in all cases.

RESULTS

In the 10 patients, the mean +/- SD end-diastolic myocardial thickness was 22.7 +/- 6.3 mm in the basal septum and 13 +/- 3.9 mm in the posterolateral wall with a ratio of 1.76 +/- 0.30; the corresponding values were 10.6 +/- 1.1, 10.4 +/- 1.1, and 1.02 +/- 0.08 mm, respectively, in five healthy volunteers. The mean systolic thickening of the basal septum was 22 +/- 12%. This value was 49 +/- 4% in the five healthy volunteers. In resting obstructive hypertrophic cardiomyopathy, septal wall thickness was > or = 25 mm with a systolic thickening of 10%. A systolic anterior motion of the mitral valve was demonstrated in four patients with resting subaortic pressure gradients ranging from 28 to 120 mm Hg. A signal void area was demonstrated within the left ventricular outflow tract during systole in the seven patients with obstructive cardiomyopathy. This signal void area reached its maximum during early systole in the most severe obstructions and during midsystole in the less severe obstructions.

CONCLUSION

In patients with asymmetric septal hypertrophic cardiomyopathy, gross correlation was demonstrated between severity of obstruction and several MR and cine MR features including increased end-diastolic thickness of the septal wall, decreased systolic thickening of the septal wall, systolic anterior motion of the mitral valve, and signal void area within the left ventricular outflow tract during systole.

MR imaging in intracystic hemorrhage of simple hepatic cysts

Intracystic hemorrhage of simple hepatic cysts is one of the most frequent complications. Ultrasonography (US) and computed tomography (CT) may show abnormal findings and mimic other diseases. We describe magnetic resonance (MR) imaging in four patients with intracystic hemorrhage confirmed by surgery or percutaneous aspiration. In all cases the lesions were hyperintense on both T1- and T2-weighted sequences. In three of the four cases the signal was heterogeneous on T1-weighted sequences. Two cases of a thickened wall and one case of a fluid-fluid level were also observed. We suggest that MR imaging may be helpful to differentiate intracystic hemorrhage from other cystic lesions by showing high signal on T1- and T2-weighted sequences.

Correlation of MR changes with Doppler US measurements of blood flow in exercising normal muscle

Muscle data from phosphorus-31 magnetic resonance (MR) spectroscopy and hydrogen-1 MR imaging and popliteal artery data from duplex Doppler ultrasound were compared during an exercise test of the anterior compartment of the leg, in nine healthy volunteers. Significant variations (mean +/- standard deviation) were observed at the end of exercise versus rest in intracellular pH (pHi) (6.32 +/- 0.02 vs 7.02 +/- 0.04, P < .001), T2 (38.2 msec +/- 2.3 vs 29.5 msec +/- 1.1, P < .001), and popliteal output (652 mL/min +/- 232 vs 149 mL/min +/- 65, P < .001). These variables showed the following significant correlations at the end of exercise: T2 and pHi (r = -.784, P < .01), T2 and popliteal output (r = .737, P < .03), and pHi and popliteal output (r = -.902, P < .001). However, during recovery, the T2 curve was significantly different from those of pHi and popliteal output. This suggests that even if circulatory conditions play a role in the maximum T2 variation during exercise, they do not directly explain T2 changes. Furthermore, the correlations involving pHi suggest the role of the metabolism of exercising muscle in transcapillary fluid movement.

US-guided percutaneous liver biopsy with plugging of the needle track: a prospective study in 72 high-risk patients

The efficiency, accuracy, and safety of ultrasound-guided liver biopsy with plugging of the needle track were prospectively assessed in 72 patients at high risk for hemorrhage. Seventy-eight biopsy procedures were performed in 72 consecutive patients prospectively classified into four different groups on the basis of coagulation parameters. Sixty-two patients (86%) had severe or moderately severe coagulation disorders. Fifty-four biopsy procedures were performed in 50 patients with diffuse liver disease, and 24 were performed in 24 patients with focal liver lesions. The biopsy track was embolized with gelatin particles and thrombin. Biopsy specimens adequate for histologic diagnosis were obtained in 69 of the 72 patients (96%). In focal lesions, accuracy and sensitivity in the diagnosis of malignancy were 75% and 89%, respectively. Two serious bleeding complications (2.8%) were encountered in two of the patients with major coagulation disorders. Liver biopsy with plugging of the needle track is a practical technique and is a feasible alternative to the transjugular approach. Respective indications for both methods depend on the severity of coagulation disorders and the presence of focal lesions.

Focal nodular hyperplasia of the liver: MR imaging and pathologic correlation in 37 patients

Thirty-seven patients with 48 lesions of focal nodular hyperplasia (FNH) underwent preoperative magnetic resonance (MR) examination and surgical resection. Sixteen lesions were imaged at 0.5 T with T1- and T2-weighted spin-echo sequences; 32 lesions were imaged at 2 T with T1-and T2-weighted spin-echo and gradient-recalled-echo sequences. Contrast material-enhanced MR imaging was performed in 20 lesions. MR imaging failed to depict six tumors that were less than 3 cm in diameter. Typical appearance was present in 18 of the 42 (43%) lesions seen at MR. Atypical lesion features included no scar (n = 15), hypointense scar on T2-weighted images (n = 7), pseudocapsule (n = 6), strong hyperintense lesion on T2-weighted images (n = 3), diffuse hyperintensity on T1-weighted images (n = 3), and heterogeneous lesion (n = 1). Comparison between findings at MR imaging and at histopathologic examination was performed in 38 lesions: There was good correlation between presence and size of the scar on both examinations. In 13 of 20 (65%) of the hyperintense scars on T2-weighted images, edema was prominent, whereas in five of the seven (71%) hypointense scars on T2-weighted images, edema was absent or low.

Facial nerve neuromas: MR imaging. Report of four cases

Four cases of facial nerve neuroma were evaluated by computed tomographic (CT) scan and magnetic resonance imaging (MRI). The extension of the tumor in the petrous bone or the parotid gland was well defined by MRI in all cases. CT scan was useful to demonstrate bone erosions and the relation of the tumor to inner ear structures. In cases of progressive facial palsy, CT and MRI should be combined to detect a facial neuroma and to plan the surgical approach for tumor removal and nerve grafting.