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Background: The present outcomes of cataract surgery in Africa do not meet the recommendations of the World Health Organization. Superior manual small incision cataract surgery (SICS) is the operation of choice in many developing countries. However, there is good evidence that temporal incisions are more stable and cause less surgically induced astigmatism (SIA)., Methods: In a prospective, non-randomized study in an anterior segment clinic in the southeastern part of Kenya, 405 eyes were operated on using either temporal phacoemulsification (n = 288) or temporal SICS (n = 117) with implantation of a rigid intraocular lens (IOL). The main outcome variables were preexisting corneal astigmatism, SIA, visual outcomes and complication rates., Results: Preoperatively, the mean astigmatism in all eyes was 1.1 diopters (D) ranging from 0 to 6.28 D. Against-the-rule astigmatism (ATR) (mean 1.18 D) was most common with 60.4%. After 8 weeks following surgery the mean SIA was 1.13 D (SD ±0.63 D) at 92° for phacoemulsification and 1.11 D (SD ±0.56 D) at 102° for SICS. Of the eyes 89.6% reached a best corrected visual acuity (BCVA)  ≥ 0.3 and 82.7% reached this visual acuity also uncorrected. The main reasons for not reaching BCVA ≥ 0.3 were ocular comorbidities., Conclusions: In the population studied most patients had preexisting ATR astigmatism and a switch to routine temporal incisions appeared beneficial. The World Health Organization recommends that poor (BCVA below 0.1) or borderline (BCVA below 0.3) outcomes after cataract surgery should not be more than 10-20%. This goal has been achieved in this study with the techniques presented.

Purpose: Comparison of a breath-hold, velocity-encoded, phase-difference magnetic resonance (MR) sequence for intracardiac shunt flow measurement with the invasive shunt size determination by oximetry., Patients and Methods: 10 patients with different cardiac shunts (6 ASD/3 VSD/1 PDA) and four healthy individuals were investigated using a 1.5 Tesla Siemens Vision system. For flow measurements a breath-hold, velocity-encoded, phase-difference magnetic resonance (MR) sequence was used ('through plane', FLASH 2D-sequence, TR/TE 110/5 ms, 'velocity encoding' 250 cm/s). Mean flow (ml/R-R interval) in the ascending aorta, the pulmonary trunk, and the right and left pulmonary arteries was determined. The ratio of the mean flow in the pulmonary circulation (Qp: sum of the mean flows in the right and left pulmonary arteries) and the systemic circulation (Qs: mean flow in the proximal aorta) was compared with the Qp/Qs ratios determined by the invasive oxymetric technique. Oximetry was performed within 24 hours after MR imaging., Results: In the 4 healthy individuals MR flow measurement yielded a Qp/Qs ratio of 0.96 +/- 0.15. In the 10 patients with the various shunt defects, the non-invasive shunt determination by MR gave a Qp/Qs ratio of 2.09 +/- 0.67. The percentage of the calculated shunt sizes was 47.05 +/- 17.45%. In the comparison with the results determined by the invasive oxymetric technique, the MR data showed a strong correlation of r = 0.87., Conclusions: Breath-hold, velocity-encoded, phase-difference MR-technique enables a reliable quantification of cardiac shunts within a short acquisition time.

A coronary artery perforation is a rare complication after percutaneous transluminal coronary angioplasty. The therapy will be determined by the hemodynamic failure of the left or right ventricle. A case of a coronary artery perforation with a shunt from the right coronary artery to the right ventricle after coronary angioplasty is reported. The shunt was detected by coronary angiography and confirmed by magnetic resonance imaging and doppler echocardiography.

The value of macromolecular contrast agents (MMCM) for the characterization of benign and malignant breast tumors will be demonstrated in this review. Animal studies suggest a high potential of MMCM to increase the specificity of MR-mammography. The concept of tumor differentiation is based on the pathological hyperpermeability of microvessels in malignant tumors. MMCM show a leak into the interstitium of carcinomas, whereas they are confined to the intravascular space in benign tumors. Capabilities and limitations of the MMCM-prototype. Albumin-Gd-DTPA, for breast tumor characterization will be summarized and compared to the standard low molecular weight contrast agent Gd-DTPA. Initial experience with new MMCM, such as Dendrimers, Gd-DTPA-Polylysine and MS-325 will be outlined. The potential of "blood-pool"-iron oxides, such as AMI-227 for the evaluation of tumor microvascular permeabilities will be discussed.

Acute pulmonary embolism (PE) is an increasing and underdiagnosed cause of mortality and morbidity in hospitalised patients: pulmonary hypertension based on chronic pulmonary embolism is an uncommon, but severe and surgically curable complication. Since clinical signs might be silent or unspecific, both acute and chronic PE require imaging methods for diagnosis and treatment planning. Chest radiographic findings are usually non-specific. Scintigraphy provides a high sensitivity for PE, but lacks anatomic resolution and sufficient specificity. Pulmonary angiography, albeit accurate, is an invasive procedure associated with low but still not negligible morbidity and mortality. Hence, non-invasive methods offer advantages. Spiral CT, for example, is most reliable in the diagnosis of acute and chronic PE: Such fast CT techniques provide a non-invasive means to detect and differentiate acute emboli and organised thrombi, as well as perfusion abnormalities and other concomitant findings. MRI offers both morphological and functional information on lung perfusion and right heart function, but its image quality still needs improvement to be comparable with CT. Thus, while MRI must still be tested in clinical studies. CT is recommended as a screening method in acute and chronic pulmonary embolism.