Field-directed sputter sharpening for tailored probe materials and atomic-scale lithography.

Fabrication of ultrasharp probes is of interest for many applications, including scanning probe microscopy and electron-stimulated patterning of surfaces. These techniques require reproducible ultrasharp metallic tips, yet the efficient and reproducible fabrication of these consumable items has remained an elusive goal. Here we describe a novel biased-probe field-directed sputter sharpening technique applicable to conductive materials, which produces nanometer and sub-nanometer sharp W, Pt-Ir and W-HfB(2) tips able to perform atomic-scale lithography on Si. Compared with traditional probes fabricated by etching or conventional sputter erosion, field-directed sputter sharpened probes have smaller radii and produce lithographic patterns 18-26% sharper with atomic-scale lithographic fidelity.

Regional peripheral vascular supply based on the superficial temporal artery in dogs and cats.

Cutaneous arterial blood supply to the temporal region was evaluated in 8 dogs and 8 cats. Subtraction radiography and angiography of the carotid and superficial temporal arteries were used in 4 dogs and 4 cats to determine arterial blood supply to the temporal region and frontalis muscle. A myocutaneous axial pattern flap based on the superficial temporal artery and frontalis muscle may be indicated for cosmetic reconstruction in dogs and cats following surgical resection of neoplastic lesions or traumatic wounds in the maxillofacial region. The frontalis muscle was identified as the thin subcutaneous continuation of the platysma muscle extending cranially and rostrally. Dissection of the temporal region in 4 dogs and 4 cats revealed the subcutaneous location of the superficial temporal artery as it continues rostrally from the caudal aspect of the zygomatic arch.

Malignant hyperthermia in a patient receiving nitrous oxide.

A patient who had malignant hyperthermia that apparently was triggered by nitrous oxide anesthesia even though he was premedicated with dantrolene sodium was successfully managed on a separate occasion using dantrolene without nitrous oxide.

Nasotracheal intubation by fiberoptic laryngoscope.

We have presented a case in which the fiberoptic laryngoscope was used for nasotracheal intubation, an alternative for the difficult laryngoscopy. We believe regional blocks combined with extensive topical anesthesia aid in the successful use of the fiberoptic laryngoscope for cases of difficult intubation in the practice of oral surgery. We were unable to obtain a complete sensory block with benzocaine or lidocaine spray since the mouth opening was less tha 1 mm. The bilateral superior laryngeal nerve block is a valuable adjunct to the procedure.

Sickle cell hemoglobinopathies: a protocol for management.

Two cases have been presented: one shows complications when a latent form of sickle cell disease was manifested after orthognathic surgery; the other illustrates a protocol for management of patients with abnormal hemoglobins who are candidates for orthognathic surgery. The protocol includes an initial screening test for all black patients who are hospitalized for elective orthognathic surgery. When the screening test is positive, afollow-up hemoglobin electrophoresis is obtained to identify the specific hemoglobinopathy. Transfusions, when indicated, are given to alter the percentages so that the patient has no greater than 40% abnormal hemoglobin. Precautions are taken during anesthesia and after surgery to ensure that the patient is well oxygenated and is not in a hypothermic state. Serial electrophoreses are performed and transfusions, if indicated, are given during the postoperative and healing phases according to the postoperative status.