[Differential diagnosis of gallbladder abnormalities : Ultrasound, computed tomography, and magnetic resonance imaging]

CLINICAL ISSUE

Due to the high prevalence of clinically suspected cholecystitis or cholecystolithiasis the gallbladder is one of the organs examined the most by imaging.

STANDARD RADIOLOGICAL METHODS

In most clinical settings ultrasound is the primary imaging method because of its wide availability, speed and superior spatial resolution. In cases of ambiguous findings or potential complications computed tomography (CT) and magnetic resonance imaging (MRI) are used.

METHODICAL INNOVATIONS

When specific problems arise these imaging modalities may be enhanced by special techniques, e. g. contrast-enhanced ultrasound or dual-energy CT, and specific MRI sequences.

PERFORMANCE

Special variants of cholecystitis, such as xanthogranulomatous cholecystitis and adenomyomatosis, may pose a particularly difficult diagnostic problem as they may resemble other diseases. Sequelae of cholecystolithiasis, such as the Mirizzi syndrome and acute bowel obstruction, may complicate the imaging algorithm as the location and the symptoms shift. Cases of neoplastic diseases of gallbladder cancer and other malignancies require a broad spectrum of imaging modalities.

ACHIEVEMENTS

Although the gallbladder can easily be examined with ultrasound, some cases require a more thorough ultrasound examination. In some cases only a combination of multiple imaging modalities yield the diagnosis. Further developments regarding technical issues and the diagnostic algorithm can be expected.

PRACTICAL RECOMMENDATIONS

Ultrasound is the best first imaging modality. In cases of ambiguous findings or clinical complications CT or MRI are recommended.

Postinterventional volume dynamics following endovascular treatment of infrarenal aortic aneurysms

AIM

Endovascular treatment of infrarenal aortic aneurysms requires follow-up to rule out complications that would require renewed intervention. The aim of this study was to define those factors which, in the absence of such complications, could be relevant for the remaining risk.

METHODS

The CT data sets of 55 patients (73.5+/-8 years; M: F ratio 49: 6) were evaluated volumetrically: immediately postinterventional, 6 months, and annually after the procedure. The median observation period was 30+/-19 months.

RESULTS

Risk factors for a further increase in aneurysm volume were: short-term increase in volume >5%, medium-term growth >20%, one-time growth >20%, no decrease in volume, and an initial aneurysm volume >200 mL. Favorable factors were: a one-time decrease in volume >15% and no increase in volume at any follow-up visit. Indifferent factors were: initial decrease in volume, one-time growth <20%, one-time shrinkage <15%, and type II endoleak. Conclusion. Patients require particular attention whose aneurysm volume increased by more than 5% or increased medium-term or increased at once by more than 20%, and who either did not show a decrease in volume at any follow-up or who had a large initial volume. A one-time decrease in volume of more than 15% was positive, as was no increase in volume at any follow-up.

Selective nontemplated adsorption of organic molecules on nanofacets and the role of bonding patterns

A key element of functionalizing nanocrystals with organic molecules is the nontemplated selective adsorption of different molecules on different facets. Here we report scanning-tunneling-microscopy images of perylene-3,4,9,10-tetracarboxylic-dianhydride and 2,5-dimethyl-N,N'-dicyanoquinonediimine on silver, demonstrating selective adsorption on different facets. We also report first-principles calculations that account for the data and show that bonding, which controls selectivity, occurs via the end atoms, while the molecule's midregion arches away from the substrate. The results are also consistent with data that have been interpreted in terms of bonding via the midregion.

Technical and clinical success of infrarenal endovascular abdominal aortic aneurysm repair: A 10-year single-center experience

OBJECTIVE

The aim of our retrospective study was to review our single-center experience with aortic abdominal aneurysm (AAA) repair retrospectively.

MATERIAL AND METHODS

From 1995 to 2005, 70 consecutive patients affected by AAA were treated by endovascular stent-graft repair. Mean follow-up was 23.9 months. Follow-up investigations were performed at 6 and 12 months and yearly thereafter. Five different stent-graft designs were compared to each other. Primary technical success (PTS), assisted primary technical success (APTS), primary clinical success (PCS) and secondary clinical success (SCS) were evaluated.

RESULTS

All over PTS was achieved in 94.3%, APTS in 97.1%, PCS in 61.4%, APCS in 64.3% and SCS in 70%. There were 3 type I endoleaks, 25 type II endoleaks, 4 type III endoleaks, 8 limb problems, 5 conversions to open surgery, 10 aneurysm sac expansions and 14 device migrations. Patients with newer generation devices showed better results than patients with first generation prosthesis. In addition results were better for grafts with suprarenal fixation (versus infrarenal fixation) and grafts with barbs and hooks (versus grafts without barbs and hooks). Patients with bad anatomic preconditions showed a higher complication rate.

CONCLUSION

Contrary to first generation products, new stent-graft designs show acceptable technical and clinical results in endovascular AAA aneurysm repair. However, this therapy still should be reserved only for patients with significant comorbities and suitable anatomic conditions.

[Parasympathicolytic treatment of abnormal neurogenic bladder function: a urodynamic study (author's transl)]

The effect of two parasympatholytic drugs, trospium chloride and hyoscine-N-butylbromide, was studied by urodynamic tests in 20 patients with spastic neurogenic bladder function. After intravenous injection of 0.6 mg trospium chloride or 60 mg hyoscine-N-butyl bromide bladder capacity increased significantly, while the degree of spasm and the response in the ice water test decreased significantly. Maximal sphincter pressure, resting bladder pressure, maximal bladder filling pressure and abdominal pressure remained unchanged.