The Chimeric Gracilis and Profunda Artery Perforator Flap: Characterizing This Novel Flap Configuration with Angiography and a Cadaveric Model.

BACKGROUND: A chimerically configured gracilis and profunda artery perforator (PAP) flap is highly prevalent based on recent computed tomography (CT)-imaging data. The purpose of this study is to further characterize the vascular anatomy of this novel flap configuration and determine the feasibility of flap dissection. METHODS: To characterize flap arterial anatomy, lower extremity CT angiograms performed from 2011 to 2018 were retrospectively reviewed. To characterize venous anatomy and determine the feasibility of flap harvest, the lower extremities of cadavers were evaluated. RESULTS: A total of 974 lower extremity CT angiograms and 32 cadavers were included for the assessment. Of the 974 CT angiograms, majority (966, 99%) were bilateral studies, yielding a total of 1,940 lower extremities (right-lower-extremity = 970 and left-lower-extremity = 970) for radiographic evaluation. On CT angiography, a chimerically configured gracilis and PAP flap was found in 51% of patients (n = 494/974). By laterality, chimeric anatomy was present in 26% of right lower extremities (n = 254/970) and 25% of left lower extremities (n = 240/970); bilateral chimeric anatomy was found in 12% (n = 112/966) of patients. Average length of the common arterial pedicle feeding both gracilis and PAP flap perforasomes was 31.1 ± 16.5 mm (range = 2.0-95.0 mm) with an average diameter of 2.8 ± 0.7 mm (range = 1.3-8.8 mm).A total of 15 cadavers exhibited chimeric anatomy with intact, conjoined arteries and veins allowing for anatomical tracing from the profunda femoris to the distal branches within the tissues of the medial thigh. Dissection and isolation of the common pedicle and distal vessels was feasible with minimal disruption of adjacent tissues. Chimeric flap venous anatomy was favorable, with vena commitante adjacent to the common pedicle in all specimens. CONCLUSION: Dissection of a chimeric medial thigh flap consisting of both gracilis and PAP flap tissues is feasible in a cadaveric model. The vascular anatomy of this potential flap appears suitable for future utilization in a clinical setting.

A Navajo Patient with Morbihan's Disease: Insight into Oculoplastic Treatment of a Rare Disease.

Morbihan's disease is classically defined as primarily a Caucasian disease of chronic, recurrent erythema and nonpitting edema of the middle and upper thirds of the face. The disease is often difficult to diagnose and challenging to treat. Medical management is the primary treatment modality; however, if there is progression of the disease that causes visual impairment, surgical debulking is often required. We present the first reported case of Morbihan's disease in a Navajo patient in conjunction with a review of the literature on surgical management of this challenging disease.

Robotic Harvest of a Rectus Abdominis Muscle Flap After Abdominoperineal Resection.

INTRODUCTION: As multidisciplinary treatment modalities for rectal cancer continue to evolve, neoadjuvant chemoradiation then surgical resection is a common approach. Robotic-assisted abdominoperineal resection is becoming more prevalent in part because of better visualization and instrument mobility within the pelvis. After abdominoperineal resection, postoperative perineal wound complications remain a significant risk. Pelvic reconstruction lowers this risk, and a pedicled rectus abdominis muscle flap is frequently used to achieve this. Traditional flap harvest requires laparotomy, resulting in violation of both rectus sheaths and a large midline scar. Robotic harvest of the rectus abdominis muscle for pelvic reconstruction after abdominoperineal resection is a novel approach with foreseeable benefits. TECHNIQUE: After completion of abdominoperineal resection, 2 additional trocars are inserted in the lateral abdomen, and the robot is reoriented toward the posterior abdominal wall. The peritoneum and posterior rectus sheath are incised, and dissection is carried superiorly and inferiorly in a sagittal plane to reveal the rectus abdominis muscle. The muscle body is separated from the anterior rectus sheath. Once the inferior epigastric artery is identified, the superior pole of the muscle is transected. Continued lateral dissection ensures flap mobility for placement within the pelvis. After obtaining proper reach, the robot is undocked, and the flap is sutured in place through the perineal defect. RESULTS: After trocar placement and robot repositioning, both the colorectal and plastic surgeons trade places at the console. Robotic flap harvest precludes the need for laparotomy. The anterior rectus sheath remains unviolated and the patient avoids an additional midline scar. The aforementioned benefits of robot-assisted abdominoperineal resection, namely increased visualization and maneuverability, were also found applicable when robotically harvesting this flap. CONCLUSIONS: This technique exemplifies an additional minimally invasive technique for patients pursuing abdominoperineal resection. With knowledge of this novel approach, surgeons can better tailor their operations to benefit the patient.

Work-Related Musculoskeletal Discomfort and Injury in Craniofacial and Maxillofacial Surgeons.

INTRODUCTION: Long, complex surgical procedures with non-ergonomic postures, headlights, loupe magnification, and microscope use may put craniofacial and maxillofacial surgeons at an increased risk of work-related musculoskeletal discomfort (WRMD). Identifying the prevalence and impact of WRMD may guide preventive strategies to prolong well-being, job satisfaction, and career duration. METHODS: A 31-question survey was designed to evaluate WRMD. The survey was sent to American Society of Craniofacial Surgeons and American Society of Maxillofacial Surgeons members. The survey was created and distributed electronically through a private survey research center (Qualtrics Survey Software). RESULTS: There were 95 respondents (23.75% response rate): 75% male, 56% aged 31 to 50 years old, and 73% in academic practice. On a scale of 0 to 10 (0 no pain, 10 worst pain), WRMD for surgery without loupes/microscope had a median of 3, with loupes 4, and with microscope 5. Pain was most common in the neck. Pain within 4 hours of surgery was present in 55% and 38% feared pain would influence future surgical performance. Surgeon discomfort affects posture (72%), stamina (32%), sleep (28%), surgical speed (24%), relationships (18%), and concentration (17%). Medical treatment for discomfort was sought by 22%. Time off work for treatment occurred in 9%. CONCLUSION: The WRMD can affect many aspects of a craniofacial or maxillofacial surgeon's life and has the potential to shorten or end a career. Occupational health and surgical ergonomics should be emphasized during surgical training and in surgical practice.

Work-Related Musculoskeletal Discomfort and Injury in Microsurgeons.

BACKGROUND: Long surgical procedures with loupe magnification and microscopes may put microsurgeons at an increased risk of musculoskeletal discomfort. Identifying the prevalence and impact of work-related musculoskeletal discomfort may guide preventive strategies to prolong well-being, job satisfaction, and career duration. METHODS: An online 29-question survey was designed to evaluate work-related musculoskeletal discomfort. The survey was created and distributed electronically through a private survey research center and was sent to the members of the American Society for Reconstructive Microsurgery. RESULTS: There were 117 respondents (16.7% response rate): 80% were men; 69% were aged 31 to 50 years; and 68% were in academic practice. On a scale of 0 to 10 (0, no pain and 10, worst pain), the median for work-related musculoskeletal discomfort for surgery without loupes or microscope was 2; with loupes, 4; and with a microscope, 5. Pain was most common in the neck. Half of the surgeons reported pain within 4 hours of surgery, and 57% feared that pain would influence future surgical performance. Surgeon discomfort affected posture (72%), stamina (36%), sleep (29%), relationships (25%), concentration (22%), and surgical speed (19%). Tremor caused by the discomfort occurred in 8%. Medical treatment for discomfort was sought by 29%. Time off work for treatment occurred for 8%. CONCLUSION: Work-related musculoskeletal discomfort can affect many aspects of a microsurgeon's life and has the potential to limit a surgeon's ability to operate. Therefore, more emphasis is needed in the surgical community on the important issues of occupational health and surgical ergonomics for microsurgeons.

Tissue Expanders and Proton Beam Radiotherapy: What You Need to Know.

Proton beam radiotherapy (PBR) has gained acceptance for the treatment of breast cancer because of unique beam characteristics that allow superior dose distributions with optimal dose to the target and limited collateral damage to adjacent normal tissue, especially to the heart and lungs. To determine the compatibility of breast tissue expanders (TEs) with PBR, we evaluated the structural and dosimetric properties of 2 ex vivo models: 1 model with internal struts and another model without an internal structure. Although the struts appeared to have minimal impact, we found that the metal TE port alters PBR dynamics, which may increase proton beam range uncertainty. Therefore, submuscular TE placement may be preferable to subcutaneous TE placement to reduce the interaction of the TE and proton beam. This will reduce range uncertainty and allow for more ideal radiation dose distribution.

Effect of rapid human N-acetyltransferase 2 haplotype on DNA damage and mutagenesis induced by 2-amino-3-methylimidazo-[4,5-f]quinoline (IQ) and 2-amino-3,8-dimethylimidazo-[4,5-f]quinoxaline (MeIQx).

Heterocyclic amines such as 2-amino-3-methylimidazo-[4,5-f]quinoline (IQ) and 2-amino-3,8-dimethylimidazo-[4,5-f]quinoxaline (MeIQx) are dietary carcinogens generated when meats are cooked well-done. Bioactivation includes N-hydroxylation catalyzed by cytochrome P4501A2 (CYP1A2) followed by O-acetylation catalyzed by N-acetyltransferase 2 (NAT2). Nucleotide excision repair-deficient Chinese hamster ovary (CHO) cells stably transfected with human CYP1A2 and either NAT2*4 (rapid acetylator) or NAT2*5B (slow acetylator) alleles were treated with IQ or MeIQx to examine the effect of NAT2 genetic polymorphism on IQ- or MeIQx-induced DNA adducts and mutagenesis. MeIQx and IQ both induced decreases in cell survival and significantly (p<0.001) greater number of endogenous hypoxanthine phosphoribosyl transferase (hprt) mutants in the CYP1A2/NAT2*4 than the CYP1A2/NAT2*5B cell line. IQ- and MeIQx-induced hprt mutant cDNAs were sequenced and over 85% of the mutations were single-base substitutions with the remainder exon deletions likely caused by splice-site mutations. For the single-base substitutions, over 85% were at G:C base pairs. Deoxyguanosine (dG)-C8-IQ and dG-C8-MeIQx adducts were significantly (p<0.001) greater in the CYP1A2/NAT2*4 than the CYP1A2/NAT2*5B cell line. DNA adduct levels correlated very highly with hprt mutants for both IQ and MeIQx. These results suggest substantially increased risk for IQ- and MeIQx-induced DNA damage and mutagenesis in rapid NAT2 acetylators.

Alkylation of a dimolybdenum SO bridge, subsequent reactions, and characterization of the thioperoxide bridge.

The SO bridge of the complex, [Mo(2)(NTo)(2)(S(2)P(OEt)(2))(2)(mu-O(2)CMe)(mu-SBn)(mu-SO)], 1, displayed nucleophilicity at O, giving alkylation products [Mo(2)(NTo)(2)(S(2)P(OEt)(2))(2)(mu-O(2)CMe)(mu-SBn)(mu-SOR)](+), 4(+), which contained the thioperoxide bridge. These cations were then subject to nucleophilic attack by two pathways. Debenzylation of the bridge thiolate in 4(+) afforded neutral [Mo(2)(NTo)(2)(S(2)P(OEt)(2))(2)(mu-O(2)CMe)(mu-S)(mu-SOR)], 5; de-esterification of a dithiophosphate ligand in 4(+) gave [Mo(2)(NTo)(2)(S(2)P(O)(OEt))(S(2)P(OEt)(2))(mu-O(2)CMe)(mu-SBn)(mu-SO)], 6, which contained a monoester, dithiophosphate ligand. Complex 1 gave a slow and clean reaction in the crystalline state, further demonstrating its nucleophilicity by attacking a neighboring molecule in its lattice. X-ray crystallography confirmed the thioperoxide linkage and revealed structural similarities of the Mo(2)(mu-SOR) unit to sulfenate esters (RSOR) and related derivatives.