Nasoseptal Flap Necrosis After Endoscopic Skull Base Surgery in the Setting of COVID-19 Pandemic.

BACKGROUND: A novel viral strain known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has created a worldwide pandemic known as coronavirus 2019 (COVID-19). Early reports from China have highlighted the risks associated with performing endoscopic endonasal skull base surgery in patients with SARS-CoV-2. We present a rare complication of nasoseptal flap (NSF) necrosis associated with COVID-19, further emphasizing the challenges of performing these procedures in this era. CASE DESCRIPTION: A 78-year-old man underwent an extended endoscopic endonasal transplanum resection of a pituitary macroadenoma for decompression of the optic chiasm. The resulting skull base defect was repaired using a pedicled NSF. The patient developed meningitis and cerebrospinal fluid (CSF) leak on postoperative day 13, requiring revision repair of the defect. Twelve days later, he developed persistent fever and rhinorrhea. The patient was reexplored endoscopically, and the NSF was noted to be necrotic and devitalized with evident CSF leakage. At that time, the patient tested positive for SARS-CoV-2. Postoperatively, he developed acute respiratory distress syndrome complicated by hypoxic respiratory failure and death. CONCLUSIONS: To our knowledge, this is the first reported case of NSF necrosis in a patient with COVID-19. We postulate that the thrombotic complications of COVID-19 may have contributed to vascular pedicle thrombosis and NSF necrosis. Although the pathophysiology of SARS-CoV-2 and its effect on the nasal tissues is still being elucidated, this case highlights some challenges of performing endoscopic skull base surgery in the era of COVID-19.

A Systematic Review of Zosteriform Rash in Breast Cancer Patients: An Objective Proof of Flap Reinnervation and a Management Algorithm.

BACKGROUND: Zosteriform rash in cancer patients provides objective clues to the process of reinnervation of the reconstructed breast. This rash should also raise suspicion for metastasis, which can be confused with herpes zoster. OBJECTIVES: The aims of this study were to explain the reconstruction flap sensory reinnervation mechanism based on the clinical findings and provide a diagnostic and management algorithm of zosteriform rash in breast cancer patients. METHODS: On November 15, 2017, we conducted a search of published articles in MEDLINE and Cochrane databases. All the articles describing a zosteriform rash in a patient with a history of breast cancer were included in this review. RESULTS: Eleven articles from the literature and 1 case from our practice were selected for inclusion in this systematic review. Five patients had a breast reconstruction with a flap. The flap skin was affected by the rash in 4 of these patients, providing an objective proof of the reinnervation of the reconstructed breast. In 6 patients, the presentation was typical, and the diagnosis of herpes zoster was made without additional diagnostic testing. In 4 cases, the eruption was atypical, and a biopsy was done to confirm the diagnosis of a cancer metastasis. In 2 patients, the rash was multidermatomal, and a polymerase chain reaction was done to confirm the diagnosis of disseminated herpes zoster. CONCLUSIONS: Zoster reactivation in breast reconstructed patients is an objective proof of the reinnervation of the skin flap. Moreover, zosteriform rash in cancer patients should raise suspicion for metastasis, which can be confused with herpes zoster.

Adenovirally delivered enzyme prodrug therapy with herpes simplex virus-thymidine kinase in composite tissue free flaps shows therapeutic efficacy in rat models of glioma.

INTRODUCTION: Free flap gene therapy exploits a novel therapeutic window when viral vectors can be delivered into a flap ex vivo. The authors investigated the therapeutic potential of an adenovirally-delivered thymidine kinase/ganciclovir prodrug system expressed following vector delivery into a free flap. METHODS: The authors demonstrated direct in vitro cytotoxicity by treating a panel of malignant cell lines with the thymidine kinase/ganciclovir system and demonstrated significant cell kill proportional to the multiplicity of infection of adenoviral vector expressing thymidine kinase. Bystander cytotoxicity was demonstrated using conditioned media from producer cells (expressing adenovirally-delivered thymidine kinase and treated with ganciclovir) to demonstrate cytotoxicity in naive tumor cells. The authors investigated the effect of adenoviral vector expressing thymidine kinase/ganciclovir therapy in vivo, using models of microscopic and macroscopic residual disease in a rodent superficial inferior epigastric artery flap model. RESULTS: The authors observed retardation of tumor volume growth in both microscopic (p = 0.0004) and macroscopic (p = 0.0005) residual disease models and prolongation of animal survival. Gene expression studies demonstrated that viral genomic material was found predominantly in flap tissues but declined over time. CONCLUSIONS: The authors describe the utility of virally delivered enzyme/prodrug therapy, using a free flap as a vehicle for delivery. They discuss the merits and limitations of this approach and the unique role of therapeutic free flaps among reconstructive techniques available to the plastic surgeon.

Fulminant herpetic keratouveitis with flap necrosis following laser in situ keratomileusis: Case report and review of literature.

A 25-year-old woman presented with redness, pain, and diminution of vision that occurred 2 weeks after microkeratome-assisted laser in situ keratomileusis (LASIK). On presentation, corneal edema, Descemet membrane folds, keratic precipitates, stromal infiltrates, and flap necrosis were observed. Delayed post-LASIK microbial keratitis was diagnosed. The patient had no history of ocular herpes. Culture and scraping showed no organisms. Immunofluorescence stain was positive for the herpes simplex virus antigen. The patient was started on oral valacyclovir, and progress was monitored through serial clinical photographs and anterior segment optical coherence tomography. Resolution began within 3 days of initiating treatment and was complete in 4 weeks.

Fat grafting as a vehicle for the delivery of recombinant adenoassociated viral vectors to achieve gene modification of muscle flaps.

BACKGROUND: The combination of gene therapy and plastic surgery may have the potential to improve the specificity that is needed to achieve clinically applicable treatment regimens. Our goal was to develop a method for gene modification that would yield sustainable production of gene products but would be less time consuming than existing protocols. METHODS: An adenoassociated virus was used to deliver gene products to pectoralis muscle flaps. Gene modification was accomplished via either direct injection or novel fat grafting techniques. RESULTS: The production of gene product was observable by both in vivo imaging and immunohistochemical staining. Gene products were not detected in tissues that were not in contact with the fat grafts that were incubated with the viral vector, indicating that the transduction stayed local to the flap. CONCLUSIONS: Using novel recombinant adenoassociated virus vectors, we have developed a method for gene delivery that is highly efficient and applicable to muscle flaps.

Cutaneous reinnervation of the rectus abdominis musculocutaneous flap after chest wall reconstruction: development of herpes zoster in the transplanted musculocutaneous flap.

We report a patient in whom herpes zoster developed in the transplanted rectus abdominis musculocutaneous flap 14 months after a chest wall reconstruction for recurrent breast cancer. Based on the distribution of the varicella zoster virus spreading along the sensory nerve fibers, we concluded that the virus spread along the reinnervated sensory nerves from the dorsal ganglia, through the intercostal nerves, and into the flap skin. It is suggested that this finding demonstrates the pathway of reinnervation into the transferred musculocutaneous flap on the chest wall.