How I do it. The pedicled temporoparietal fascia flap for skull base reconstruction after endonasal endoscopic approaches.

BACKGROUND: Endoscopic endonasal approaches (EEA) are an alternative for removing challenging nasopharyngeal or skull base lesions. In some cases, a nasoseptal flap (NSF) is not always available and such complex procedures may lead to carotid arteries exposition and/or dura mater (DM) wide opening. Meticulous carotid coverage and DM reconstruction are crucial for preventing early and delayed complications. METHOD: We propose a step-by-step description of the pedicled temporoparietal fascia flap (TPFF) technique, with a focus on its pitfalls, advantages and limits. CONCLUSION: The TPFF is a reliable flap for skull base reconstruction when other pedicled flaps are not available. KEY POINTS: 1. Reliable flap even for irradiated patients 2. CT angiography with 3D reconstruction as pre-operative imaging 3. Doppler ultrasound probe to draw the artery's trajectory on skin 4. TPFF elevation concomitantly to the endoscopic procedure 5. Hemicoronal incision sufficient to harvest the TPFF 6. Superficial dissection in a plane just beneath the hair follicles 7. Dissection plane deep to the fad pad to preserve the frontal branch of the facial nerve 8. Surgical corridor wide enough to avoid any compression of the pedicle 9. Double visualization to avoid any twist and Doppler control of the STA patency 10. Close follow-up, toilet in clinics.

Extended Endoscopic Endonasal Approach for a Giant Parasellar Epidermoid Cyst.

Epidermoid cysts are rare lesions which typically grow slowly. For this reason, these lesions are usually discovered when they are already very large. The parasellar location is no exception to this rule and may involve the cavernous sinus or the Meckel cave. We present a 34-year-old female patient without past medical history who was admitted in our tertiary referral center for episodes of diplopia in the right lateral gaze and right trigeminal dysesthesias. Brain magnetic resonance imaging (MRI) showed a large right parasellar mass with mixed intensity signal on the T1 and T2 sequences, without contrast enhancement and a typical hypersignal intensity on diffusion-weighted sequences evoking an epidermoid cyst. We discuss the radiologic criteria which differentiate the lesions originating in the cavernous sinus from those of the Meckel cave ( Figs. 1 and 2 ). Parasellar tumors may be approached through classical transcranial approaches such the epidural temporopolar or the subtemporal approach which involve a significant degree of brain retraction. The last decade witnessed the advent of extended endonasal approaches which offer an interesting alternative and avoid the manipulation of the brain. We used the endoscopic transpterygoid approach in our patient and we were able to achieve an excellent clinical and radiological result. We discuss the nuances of the technique and present the surgical steps of the procedure ( Figs. 3 and 4 ). The endoscopic endonasal approach represents an excellent therapeutic option for parasellar lesions. A thorough knowledge of the anatomy and experience with endoscopic techniques are obvious prerequisite. The link to the video can be found at: https://youtu.be/QonSvHrCwOU .

Malleostapedotomy for otosclerosis, our experience of nitinol piston on twelve patients.

OBJECTIVE: Malleostapedotomy allows to completely by-pass the incus in otosclerosis surgery. Recently its use has been rivaled by hydroxyapatite cement for cases of mild and moderate necrosis of the incus. However, it remains gold standard for cases of extensive necrosis, incus dislocation, or epitympanic fixation. Modern heat-crimping pistons make surgery easier and safer. This study focuses on our experience with this technique. METHODS: Retrospective analysis of patient's files and pre- and post-operative audiograms, for cases of surgically treated otosclerosis with malleostapedotomy. RESULTS: Twelve patients underwent malleostapedotomy for otosclerosis between 2011 and 2019. Amongst them there were 10 revision surgeries and 2 primary cases. 75% had incus long-process necrosis, 17% had epitympanic fixation and one had a history of incus transposition. Nine patients (75%) had closure of air-bone gap (ABG) of <10 dB (p < 0.001) and 11 (92%) had a threshold of 20 dB (p < 0.001). Mean pre-operative ABG was 31 dB (15 dB-55 dB), and mean post-operative ABG was 7 dB (0 dB-21 dB; p < 0.001). There was no sensorineural hearing loss nor any other post-operative complication. CONCLUSIONS: Malleostapedotomy is a safe and reliable technique, allowing an ABG closure comparable to conventional incus to vestibule prosthesis. It remains the preferred technique whenever the incus cannot be used.

Olfactory Neuroblastoma.

Olfactory neuroblastoma is a rare tumor. Nasal endoscopy typically identifies a soft mass arising from the olfactory cleft. Computer tomography and magnetic resonance imaging are mandatory for staging (in association with 18F-fluorodeoxyglucose positron emission tomography) in high-grade and/or high-stage tumors. Biopsy must be representative to confirm a diagnosis and for grading purposes. Two complementary classifications are described: one (Kadish) based on clinical-radiological analysis, and the other (Hyams) on histological criteria. Based on Hyams grading, studies have pointed out that grades III-IV entail significantly different behavior and prognosis. A multimodal approach, which may combine surgery, chemotherapy, and radiotherapy, is essential to manage these tumors. Treatment schedules which include surgery seem to be superior to others. Surgery classically consisted of anterior craniofacial resection to obtain good exposure. However, the role of transnasal endoscopic surgery has expanded because of its association with fewer complications, shorter hospital stays, and comparable oncologic results to the open surgical techniques. Unilateral endoscopic craniectomy can be performed for limited lesions to avoid definitive anosmia. Treatment that includes radio- and chemotherapy is recommended for advanced and high-grade tumors. The role of neoadjuvant chemotherapy in advanced-stage lesions is emerging. The main prognostic factors associated with poor patient outcome are Hyams grade III-IV, Kadish C-D, and positive surgical margins. Lifelong follow up is recommended.

Tophaceous gout of the middle ear.

We present a very rare case of tophaceous gout of the middle ear causing conductive hearing loss, with special emphasis on Computed Tomography presentation.

Cartilage Ossiculoplasty from Stapes to Tympanic Membrane in One-Stage Intact Canal Wall Tympanoplasty for Cholesteatoma.

OBJECTIVE: To report hearing results of cartilage interposition ossiculoplasty in one-stage intact canal wall (ICW) tympanoplasty for cholesteatoma with intact stapes. MATERIALS AND METHODS: A retrospective study of pre and postoperative hearing status was conducted at a tertiary referral otologic center in a series of 61 patients having undergone one-stage ICW tympanoplasty for cholesteatoma with intact stapes and cartilage ossiculoplasty during the same procedure. RESULTS: In the preoperative period, the mean air conduction thresholds (AC), air-bone gap (ABG), and speech reception thresholds (SRT) were 35.3, 20.14, and 35.6 dB, respectively. Postoperatively, with a mean follow-up of 29 months, AC, ABG, and SRT were 27.8, 13.34, and 28.8 dB, respectively. Mean hearing gain was 6.8 dB and mean SRT improvement was 6.8 dB. Mean bone conduction thresholds for 1, 2, and 4 kHz remained stable after surgery (17.6 dB preoperatively vs. 18 dB postoperatively). CONCLUSION: Cartilage ossiculoplasty from stapes to tympanic membrane in one-stage ICW tympanoplasty for cholesteatoma is a safe, reliable, easy, and effective procedure, with no additional cost.

Stimulation of the toll-like receptor 3 promotes metabolic reprogramming in head and neck carcinoma cells.

In this study, a possible link between the innate immune recognition receptor TLR3 and metabolic reprogramming in Head and Neck carcinoma (HNC) cells was investigated. The effects of TLR3 stimulation/knock-down were assessed under several culture conditions in 4 HNC cell-lines by cell growth assays, targeted metabolomics, and glycolysis assays based on time-resolved analysis of proton release (Seahorse analyzer). The stimulation of TLR3 by its synthetic agonist Poly(A:U) resulted in a faster growth of HNC cells under low foetal calf serum conditions. Targeted analysis of glucose metabolism pathways demonstrated a tendency towards a shift from tricarboxylic acid cycle (Krebs cycle) to glycolysis and anabolic reactions in cells treated with Poly(A:U). Glycolysis assays confirmed that TLR3 stimulation enhanced the capacity of malignant cells to switch from oxidative phosphorylation to extra-mitochondrial glycolysis. We found evidence that HIF-1α is involved in this process: addition of the TLR3 agonist resulted in a higher cell concentration of the HIF-1α protein, even in normoxia, whereas knocking-down TLR3 resulted in a lower concentration, even in hypoxia. Finally, we assessed TLR3 expression by immunohistochemistry in a series of 7 HNSCC specimens and found that TLR3 was detected at higher levels in tumors displaying a hypoxic staining pattern. Overall, our results demonstrate that TLR3 stimulation induces the Warburg effect in HNC cells in vitro, and suggest that TLR3 may play a role in tumor adaptation to hypoxia.