Faculty Bibliography

For vascular anastomosis, use of topical photosensitizing dye enhances selective delivery of laser energy to target tissue, thus reducing the amount of collateral thermal injury and threshold power required for welding. For fluorescein isothiocyanate (FITC)--stained rabbit aorta in vitro, the threshold for tissue blanching was 15 seconds of 100 mW exposure of cw argon ion laser compared with 15 seconds at 300 mW for unstained tissue. The threshold power density needed for argon laser welding of abdominal aortotomies in rabbits in vivo was 3.8 W/cm2 with FITC and 7.6 W/cm2 without the dye. However, bursting pressures for the two groups (164 mm Hg with FITC, 147 mm Hg without FITC) were not significantly different. Histology revealed decreased collateral thermal damage in FITC-enhanced welds. Use of photosensitizing dyes for tissue welding is feasible and may allow arterial welding with lower power laser systems and cause less thermal trauma by lowering threshold power levels

A scheme for surgery in patients with avulsed roots is represented by a rat model whose left sciatic nerve was grafted upon the right sciatic nerve, the proximal end of the graft being introduced into the spinal cord white matter. Transcranial stimulation, EMG recording, HRP and histological studies proved that the communication between the brain and the denervated muscles may be reestablished via the motoneurons, through the graft, bypassing the motor roots. Behavioral techniques were developed and will be tested in the future. The possibility of using neurotrophic drugs will be considered

The authors' experience in the management of brachial plexus injuries over three periods of evolution is presented. Developments in microsurgery have expanded the strategies in brachial plexus management, and these are discussed in full

The author introduced this muscle for the first time almost a decade ago, and this is the first extensive description of the intricate microanatomy of this complex but unique microneurovascular muscle unit. Advantages and disadvantages and indications and contraindications for its use in facial paralysis are presented in detail from an extensive clinical experience of almost 50 such microneurovascular transfers. Pitfalls that the reconstructive microsurgeon should beware and strengths in using this muscle for facial palsy are highlighted. The detailed operative approach is presented, with promise of undetectable scars and minimal functional loss. The strategies for how to inset this muscle unit in the new recipient site are given, along with the thought processes involved in selecting the actual sites of anchoring the muscle to reproduce a mirror image of the contralateral normal face. Finally, an exemplary clinical case demonstrating the use of the pectoralis minor muscle for both eye and lower face reanimation is presented in detail, demonstrating the dual nerve supply and the resulting independent eye and smile movements with total lack of mass action and/or synkinesis. Restorations of eye blink and of a symmetrical and coordinated smile are the frequent rewards of using this unique muscle for the correction of facial palsy

The fascial layers of the temporal and occipital regions of the scalp were examined in 11 fresh cadavers. In the temporal region, three independently vascularized layers were isolated, all of which could be elevated on a single superficial temporal artery, but separated to remain independently vascularized from specific branches of this parent trunk. In the occipital area, the occipital vessels could be dissected to yield a long pedicle for an independent, fascial territory that could be transposed locally or elevated as a free flap and that will, in all likelihood, carry vascularized occipital bone. Realized and as yet unrealized uses of these ultrathin vascularized tissues remain boundless. Three representative cases are presented

The legal doctrine of informed consent has struck a chord of fear in most dental practitioners today. This, in turn, has caused many orthodontists to assume a defensive attitude in their practices. A better posture might be to use informed consent to their own and their patients' best advantage. This is accomplished by using the doctrine to enhance patients' education and understanding of their orthodontic problems, the benefits of corrective therapy, any risks associated therewith, and viable treatment alternatives. The end result is an open and honest relationship with the patients, which promotes doctor/patient autonomy.

The impending no-reflow (NRF) state was studied in the rat hindlimb to identify possible biochemical mediators producing the no-reflow phenomenon. After 5 hours of ischemia, the venous effluents draining the ischemic limb and the contralateral nonischemic limb were collected for three 30-minute time periods. Thromboxane B2 (TxB2), prostaglandin E2 (PGE2), and 6-ketoprostaglandin F1 alpha, the stable metabolite of prostacyclin (PGI2), were measured by radioimmunoassay. Venous outflow rate, distal skin perfusion assessed by dermofluorometry, and histology of muscle and skin were examined in control limbs, ischemic limbs, and limbs with impending no reflow. The no-reflow state was characterized by a significantly decreased venous outflow (less than 0.01 ml per minute), decreased skin perfusion (index of fluorescence of 15 percent in no-reflow limbs versus 70 percent in reflow limbs), and absence of thrombosis of the vasculature. The no-reflow state also was associated with 2.4 times more thromboxane B2 and 1.5 times more 6-ketoprostaglandin F1 alpha than that observed in ischemic limbs with reflow. The biosynthesis of vasodilating prostaglandin E2 in the no-reflow state, however, was only 40 percent of the prostaglandin E2 measured in limbs with reflow. We propose that the impending no-reflow state may reflect a state of global microcirculatory "agonal" vasoconstriction, most probably due to an overabundant release of the vasoconstrictor thromboxane relative to the vasodilating prostaglandin E2 and prostacyclin. The likelihood of specific biochemical mechanisms producing the no-reflow state suggests that pharmacologic agents may be able to reverse the impending no-reflow state to improve tissue survival.