Stefano Cotrufo

Topographic anatomy of the nerve to masseter: An anatomical and clinical study

BACKGROUND The use of the motor nerve to masseter has proved to be a reliable and sensible solution in facial reanimation as a donor for free muscle transfer. In this paper we describe the topographic anatomy of the nerve to masseter and our original technique for its quick and safe harvesting. METHODS This anatomical study is based on the dissection of the nerve to masseter in 17 embalmed cadaverous sites and is focused on the anatomical relations between the nerve and the surrounding structures. Also buccal and zygomatic branches of the facial nerve were dissected and assessed and the resulting data are compared. RESULTS The nerve to masseter has a predictable track inside the muscle which can be identified topographically within a square area under the zygomatic arch. This area is different between males and females and its accuracy has been tested on six patients at the Canniesburn Unit. CONCLUSIONS The nerve to masseter emerges in a very predictable point from the mandibular notch - immediately below the zygomatic arch - to run within the muscle belly. The approach here described allows safer and faster harvesting of the nerve to masseter with minimal dissection through the muscle.

Vacuum-Assisted Closure for the Treatment of Fournier’s Gangrene

Background: Fournier’s gangrene (FG) is a very aggressive necrotizing fasciitis involving subcutaneous fat and skin of scrotal and perineal regions. Vacuum-assisted closure (VAC) is a well-known method used to treat complex wounds. The authors for the first time enhance a multimodal strategy to treat the FG using VAC, reducing the number of surgical debridements, allowing a one-step surgical reconstruction with locoregional fasciocutaneous flap. Methods: Six patients with the diagnosis of FG were reviewed retrospectively at our institution. All patients were affected by very extensive FG. The FG Severity Index (FGSI) was used to evaluate the prognosis of the case at admission. Following the acute phase (24–48 h), VAC was used to achieve wound cleaning and prepare the area to a single-stage reconstruction with superomedial thigh flap. Hyperbaric oxygen therapy was also used before final reconstruction. Results: The average FGSI was 10.5, ranging from 8 to 12. All patients survived and were completely healed at the mean follow-up time of 9 months (range 3–30 months). Conclusions: VAC therapy is effective to clean and prepare the wounds, cutting off the fasciitis process and reducing the hospital stay and patient discomfort. Multidisciplinary treatment is mandatory during this devastating infection.

A Functional Magnetic Resonance Imaging Paradigm to Identify Distinct Cortical Areas of Facial Function: A Reliable Localizer

Background: Irreversible facial paralysis can be surgically treated by importing both a new neural and a new motor muscle supply. Various donor nerves can be used. If a nerve supply other than the facial nerve is used, the patient has to adapt to generate a smile. If branches of the fifth cranial nerve are used, the patient has to learn to clench teeth and smile. Currently, controversy exists regarding whether a patient develops a spontaneous smile if a nerve other than the facial nerve is used. The authors postulate that brain adaptation in facial palsy patients can occur because of neural plasticity. The authors aimed to determine whether functional magnetic resonance imaging could topographically differentiate activity between the facial nerve– and the trigeminal nerve–related cortical areas. Methods: A new paradigm of study using functional magnetic resonance imaging based on blood oxygen level–dependent signal activation was tested on 15 voluntary healthy subjects to find a sensitive localizer for teeth clenching and smiling. Subjects smiled to stimulate the facial nerve–related cortex, clenched their jaws to stimulate the trigeminal nerve–related cortex, and tapped their finger as a control condition. Results: Smiling and teeth clenching showed distinct and consistent areas of cortical activation. Trigeminal and facial motor cortex areas were found to be distinct areas with minimal overlapping. Conclusions: The authors successfully devised a functional magnetic resonance imaging paradigm effective for activating specific areas corresponding to teeth clenching and smiling. This will allow accurate mapping of cortical plasticity in facial reanimation patients. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, IV.

The vascular anatomy of the rat superficial epigastric flap by vascular corrosion casting and technical refinement for the study of choke vessels in cadaveric flap models

Accurate depiction of cutaneous vascular microanatomy is of relevance to plastic surgical flap research, and to descriptive anatomy. Yet current techniques have not permitted full visualization of the subdermal plexus, or potential angiosomal connections. Nor has endothelial visualization been facilitated. Vascular corrosion casting techniques are promising in that regard, and were applied in an extended lateral thoracoabdominal suprafascial adipocutaneous flap in the rat (based on the superficial epigastric bundle). Technical refinements for application to further study of human cadaveric flap models are presented. The intraflap vascular branching pattern of the superficial epigastric artery is described, with filling of the lateral thoracic, intercostals, and iliolumbar angiosomes found when coagulation of vessels at the periphery was delayed until after clearance. The vascular casting protocol presented is an effective and promising tool for the study of macro- and microvascular anatomy.