(AALs) Acoustically active lipospheres and ultrasound are under development to deliver bioactive molecules to the vascular endothelium. The AALs are similar to both ultrasound contrast agents and drug-delivering liposomes. They can carry bioactive substances using biologically inert shells and deliver those substances when disrupted by ultrasound.
The lipospheres consist of a small gas microbubble surrounded by a thick oil shell and are enclosed by an outermost lipid layer. The gas bubble contained in these vehicles makes them acoustically active, similar to ultrasound contrast agents. Acoustically active lipospheres can be nondestructively deflected using ultrasound radiation force, and fragmented with high intensity ultrasound pulses. Their lipid-oil complex can carry bioactive substances at high concentrations. An optimized sequence of ultrasound pulses can deflect the AALs toward a vessel wall then disrupt them, painting their contents across the vascular endothelium.

See also Filling Gas, and MRX 115.

Any abnormal reaction of a patient to an examination or procedure, like for example side effects of contrast agents or claustrophobia. Claustrophobic attacks as can happen with MRI are unknown with ultrasound examinations. Adverse reactions with ultrasonic contrast agents are very infrequent. In general, adverse reactions increase with the quantity of contrast media and also with the osmolarity of the compound.
Most frequently encountered adverse reactions are: Heat sensation, dizziness, nausea, hypotension due to vasodilatation, which can progress to hypotensive shock and anaphylactic reactions.

Albunex and Infoson, used mainly in cardiac evaluations, are first generation one-pass-only contrast agents and have been replaced by the new-generation contrast media. Albunex and Infoson are the same sonicated human serum albumin microbubbles. Infoson is licensed and manufactured in Europe, while Albunex was produced in the USA.
Albunex, an air-filled microbubble with a denatured albumin shell (modified from air-filled albumin microspheres prepared from sonicated 5% human serum albumin), was the first FDA-approved contrast agent, but is no longer in production.
Cardiac shunts and valve regurgitations are often evaluated with Color Doppler Imaging (CDI), which also improved with injections of Albunex, but this agent is pressure-sensitive and does not recirculate. It is effectively a one-pass-only agent, limiting its clinical efficacy.

See also First generation USCA, Echocardiography and Contrast Enhanced Ultrasound.

California-based research and development company. Alliance Pharmaceutical Corporation. The principal activities of the Company is identifying, designing, and developing novel medical products. The Company is engaged in development of scientific discoveries into medical products and licensing these products to multinational pharmaceutical companies in exchange for fixed payments and royalty or profit sharing payments. The Company has developed three innovative products through initial clinical (human) trials. The products are Oxygent™, Liquivent and Imavist™. The Company's strategy is to identify potential new medical products though its own efforts and scientific collaborations with researchers and clinicians in universities and medical centers. In Dec 2000 the company acquired Molecular Biosystems Inc a developer of intravenous ultrasound contrast agent for the heart.

'September 20, 2001 Alliance Pharmaceutical Corp. announced that it has won a favorable Final Judgment from the United States Patent and Trademark Office's Board of Patent Appeals and Interferences regarding claims in U.S. Patent No. 5,558,854, which is owned by Nycomed Imaging, AS. The Final Judgment determined that claims made in the Nycomed patent with respect to 'microbubbles' that contain perfluorohexane filling gas are invalid and are therefore unpatentable.'
June 04, 2010, the company announced in their quartzerly report: 'We no longer have working capital to fund our operations. Because adequate funds have not been available to us in the past, we have already delayed our Oxygent development efforts and have eliminated our other product development programs.'

Ultrasound Contrast Agents:

By Byk-Gulden (now Altana);
The transpulmonary echo contrast agent under development, BY 963, promises to be an excellent ultrasound contrast agent for the noninvasive assessment of left ventricular function. Intravenous administration of BY 963 phospholipid microbubbles improves the reproducibility of e.g. quantitative analysis.