Marc D. Liang

The use of high-frequency ultrasound for the dissection of small-diameter blood vessels and nerves

The Cavition ultrasonic surgical aspirator has been successfully used in general surgery and neurosurgery. We have explored its use in the dissection of small-diameter blood vessels and nerves (1-2 mm) in a rat model. Our results seem to indicate that this technique may be useful in isolating blood vessels surrounded by fatty tissue without damage to the vessel itself. In this study, however, high-frequency ultrasound did cause significant damage to peripheral nerves.

Magnetic ports in tissue expanders―A caution for MRI

Although a great deal is known about the potential hazards of ferromagnetic materials relative to MRI, little has been written about the safety of tissue panders. Recently a new modification of the existing ports has been made available by incorporating a magnet for ease of identification of the injection site. Despite its low mass, the intrinsic magnetic field presents a contra-indicating factor due to the potential for torque and movement in the presence of the strong magnetic field found in the clinical MR imagers. With any evidence of tissue expander prosthesis obtained in the history, a careful questioning about the possibility of a magnetic port should be carried out.

Evaluation of facial fat distribution using magnetic resonance imaging.

Magnetic resonance imaging (MRI) provides noninvasive images of facial and neck fat for a variety of conditions. It accurately maps the soft tissues pre- and postoperatively, enabling surgeons to precisely and objectively assess results of soft tissue facial contouring and fat transplantation. The risks of MRI are few. It has the potential to provide aesthetic surgeons with a more “scientific” means of comparing various techniques of fat contouring.

Successful Cryopreservation of Microvenous Allografts

Vein grafts are used in approximately 20% of microsurgical cases. Although autogenous veins currently form the major source, they are associated with increased operating time and donor site scars. Cryopreserved allograft veins may serve as an alternative source. To our knowledge, cryopreservation of veins (1 mm or less) has not been reported. In this article we have described the process of cryopreserving rat veins (less than 1 mm in diameter) and their preliminary use as interpositional vein grafts.

Magnetic Resonance Imaging of Facial Lipodystrophy: Pre- and Post-Adipose Injection

* Pittsburgh NMR Institute, Department ofRadiology, University of Pittsburgh, Pittsburgh. Pennsylvania t Department of Plastic Surgery, University of Pittsburgh, Pittsburgh. Pennsylvania A patient with facial lipodystrophy was examined with magnetic resonance imaging (MRI) before, immediately after subcutaneous injection of adipose tissue into the cheeks, and 5 months later. The MRI images clearly show the absence of native facial adipose tissue, the injected adipose tissue, and its gradual reabsorption. MRI proves useful for delineating and demonstrating the dynamics of soft tissue structures.