Pituitary Abscess: A Challenging Preoperative Diagnosis-A Multicenter Study.

Background and Objectives: Pituitary abscess (PA) is a rare occurrence, representing less than 1% of pituitary lesions, and is defined by the presence of an infected purulent collection within the sella turcica. Pas can be classified as either primary, when the underlying pituitary is normal prior to infection, or secondary, when there is associated a pre-existing sellar pathology (i.e., pituitary adenoma, Rathke's cleft cysts, or craniopharyngioma), with or without a recent history of surgery. Preoperative diagnosis, owing to both non-specific symptoms and imaging features, remains challenging. Treatment options include endonasal trans-sphenoidal pus evacuation, as well as culture and tailored antibiotic therapy. Methods: A retrospective multicenter study, conducted on a prospectively built database over a 20-year period, identified a large series of 84 patients harboring primary sellar abscess. The study aimed to identify crucial clinical and imaging features in order to accelerate appropriate management. Results: The most common clinical presentation was a symptom triad consisting of various degrees of asthenia (75%), visual impairment (71%), and headache (50%). Diagnosis was achieved in 95% of cases peri- or postoperatively. Functional recovery was good for visual disturbances and headache. Pituitary function recovery remained very poor (23%), whereas the preoperative diagnosis represented a protective factor. Conclusions: In light of the high prevalence of pituitary dysfunction following the management of PAs, early diagnosis and treatment might represent a crucial issue. Currently, there are no standard investigations to establish a conclusive preoperative diagnosis; however, new, emerging imaging methods, in particular nuclear imaging modalities, represent a very promising tool, whose potential warrants further investigations.

Airway replacement using stented aortic matrices: Long-term follow-up and results of the TRITON-01 study in 35 adult patients.

Over the past 25 years, we have demonstrated the feasibility of airway bioengineering using stented aortic matrices experimentally then in a first-in-human trial (n = 13). The present TRITON-01 study analyzed all the patients who had airway replacement at our center to confirm that this innovative approach can be now used as usual care. For each patient, the following data were prospectively collected: postoperative mortality and morbidity, late airway complications, stent removal and status at last follow-up on November 2, 2021. From October 2009 to October 2021, 35 patients had airway replacement for malignant (n = 29) or benign (n = 6) lesions. The 30-day postoperative mortality and morbidity rates were 2.9% (n = 1/35) and 22.9% (n = 8/35) respectively. At a median follow-up of 29.5 months (range 1-133 months), 27 patients were alive. There have been no deaths directly related to the implanted bioprosthesis. Eighteen patients (52.9%) had stent-related granulomas requiring a bronchoscopic treatment. Ten among 35 patients (28.6%) achieved a stent free survival. The actuarial 2- and 5-year survival rates (Kaplan-Meier estimates) were respectively 88% and 75%. The TRITON-01 study confirmed that airway replacement using stented aortic matrices can be proposed as usual care at our center. Clinicaltrials.gov Identifier: NCT04263129.

Imaging of facial neuritis using T2-weighted gradient-echo fast imaging employing steady-state acquisition after gadolinium injection.

BACKGROUND: MRI is the modality of choice for the imaging of facial neuritis. Previously, gadolinium-enhanced T1-weighted imaging of the petrous bone, then FLAIR sequences were thought to be most informative for acute facial neuritis imaging. The aim of this study is to evaluate the value of contrast-enhanced T2-weighted sequence for the diagnosis of acute facial neuritis and compare it to contrast-enhanced T1-weighted and FLAIR sequences. METHODS: We included 50 patients with an acute unilateral idiopathic peripheral facial neuritis. An MRI (3 T) with three sequences was performed (T1-weighted, T2-weighted and FLAIR), all acquired after intravenous contrast-media injection. RESULTS: The contrast-enhanced T2-weighted sequence appeared to be the most accurate one for the diagnosis of acute facial neuritis (Se 94%, Sp 100%, accuracy 98.2%, p < 0.001), with a pathological facial nerve strongly (grade 2-3) enhancing and a homogenous enhancement along the course of the entire facial nerve. Contrast-enhanced T1-weighted (Se 80%, Sp 100%, accuracy 94.1%) and FLAIR sequences (92%, Sp 88%, accuracy 90%, p < 0.001) showed lower accuracy. On T1-weighted sequence, a strong enhancement (blurred margins) of the canalicular segment was observed in 80% of the cases when it was never observed in normal nerves. CONCLUSION: A strong (= iso to hyperintense to the petrous fat signal) and diffuse (all segments) enhancement of the facial nerve on T2-weighted steady-state free precession sequence is a sensitive and specific sign for the diagnosis of acute idiopathic facial neuritis, and appears superior to T1WI and FLAIR sequences.

3D-printed simulator for nasopharyngeal swab collection for COVID-19.

INTRODUCTION: Testing for COVID-19 is a cornerstone of pandemic control. If conducted inappropriately, nasopharyngeal swab collection can be painful and preanalytical sample collection errors may lead to false negative results. Our objective was to develop a realistic and easily available synthetic simulator for nasopharyngeal swab collection. MATERIALS AND METHODS: The nasopharyngeal swab collection simulator was designed through different development steps: segmentation, computer-aided design (CAD), and 3D printing. The model was 3D printed using PolyJet technology, which allows multi-material printing using hard and soft materials. RESULTS: The simulator splits in the parasagittal plane close to the septum to allow better visualization and understanding of nasal cavity landmarks. The model is able to simulate the softness and texture of different structural elements. The simulator allows the user to conduct realistic nasopharyngeal swab collection. A colored pad on the posterior wall of the nasopharynx provides real-time feedback to the user. The simulator also permits incorrect swab insertion, which is of obvious benefit from a training perspective. Comprehensive 3D files for printing and full instructions for manufacturing the simulator is freely available online via an open access link. CONCLUSION: In the context of the COVID-19 pandemic, we developed a nasopharyngeal swab collection simulator which can be produced by 3D printing via an open access link, which offers complete operating instructions.

Evaluation of a new balloon for fetal endoscopic tracheal occlusion in the nonhuman primate model.

OBJECTIVE: We developed a new balloon called "Smart-TO," which allows noninvasive and easy unplugging, thanks to a magnetic valve actuated by the magnetic fringe field of a magnetic resonance imaging (MRI) scanner. The objective of this feasibility study was to evaluate the operation of this new balloon in a nonhuman primate model. METHODS: Four pregnant rhesus monkeys underwent fetal endoscopic tracheal occlusion using the "Smart-TO" balloon. The pregnant monkeys were simply carried around the perimeter of an MRI scanner a few days later. Study outcomes were feasibility of fetal tracheal occlusion using the "Smart-TO" balloon, persistence of the balloon in the fetal trachea, and deflation of the balloon when subjected to the magnetic fringe field of an MRI. RESULTS: At the time of the unplug procedure, in all cases, the balloon was still in a correct position, and its shape did not change based on their ultrasound appearance. After bringing the pregnant monkeys into the fringe field of the MRI scanner, the balloon deflated in all cases. CONCLUSION: The balloon we developed allows noninvasive, easily triggered, and externally controlled reversal occlusion, based on the nonhuman primate model. Further tests evaluating occlusiveness and potential adverse effects are necessary.

The Endonasal Endoscopic Approach to Pathologies of the Anterior Craniocervical Junction: Analytical Review of Cases Treated at Four European Neurosurgical Centres.

Supported by preliminary anatomical and clinical studies exploring the feasibility and usefulness of approaching many ventral pathologies of the craniocervical junction (CCJ) using the endoscopic endonasal approach, four European centres have joined forces to accumulate and share their growing surgical experience of this advanced technique. By describing the steps that led to the development and continuous refinement of this approach to the CCJ, this article delves deeply into an analysis of the cases operated on since 2010 at these four institutions, and discusses in detail the operative nuances that so far have allowed achievement of successful outcomes with excellent perioperative patient comfort and satisfactory long-term quality of life.

Prospective, randomized, controlled, open-label study to compare efficacy of a mineral-rich solution vs normal saline after complete ethmoidectomy.

PURPOSES: The purpose of this study was to compare the efficacy of a mineral-rich solution vs normal saline solution (0.9% NaCl) following endoscopic complete bilateral ethmoidectomy. METHODS: This was a prospective, multicenter, randomized, controlled, open-label trial in subjects suffering from steroid-resistant sinonasal polyposis. Adults performed 4 nasal irrigations of mineral or saline solutions daily for 28 days. Evaluations included subject-reported RHINO quality of life (QoL) and NOSE scores, tolerability, and satisfaction, the Lund-Kennedy endoscopic score and assessments of crusting, secretions and mucociliary clearance (rhinoscintigraphy). RESULTS: A total of 189 subjects were randomized. Clinically relevant improvements (> 20 points) in RhinoQOL and NOSE scores were measured in both groups without any significant inter-group difference. Among the subjects with impaired RhinoQOL at pre-inclusion, the change in Impact-RhinoQOL score was significantly superior in mineral-rich vs saline solution at day 21 (p = 0.028) and day 28 (p = 0.027). The Lund-Kennedy score continuously improved in both groups earlier with the mineral-rich solution. Crusts were significantly fewer in number and less severe/obstructive in patients receiving mineral-rich vs saline solution at day 7 (p = 0.026) and day 14 (p = 0.016). Furthermore, secretions disappeared significantly more quickly and were less thick/purulent with mineral-rich solution at day 14 (p = 0.002) and day 21 (p = 0.043). Less epistaxis was reported in the mineral vs saline solution (p = 0.008 at day 21). CONCLUSIONS: Our findings indicate that the composition of a nasal irrigation solution influences endoscopic scores and QoL after sinus surgery for patients over 60, those with an initially poor QoL and higher symptom score, and smokers.

Experience with Transcordal Silicone Stents in Adult Laryngotracheal Stenosis: A Bicentric Retrospective Study.

BACKGROUND: Benign stenosis involving laryngeal and upper tracheal structures represents a therapeutic challenge. Open surgery and endoscopic management have to be discussed by a multidisciplinary board in order to evaluate the risk and benefit for each patient. OBJECTIVE: The objective of this retrospective study was to report the experience of two French centers with transcordal silicone stents (TSS) in the endoscopic management of benign laryngotracheal stenosis (BLTS) in adults, with focus on efficacy, safety, and tolerability. METHODS: We performed a retrospective chart review of all cases of BLTS treated with TSS between January 2001 and June 2017 at two tertiary centers in France: the Centre Hospitalier Régional Universitaire de Strasbourg and the Hôpital Nord de Marseille. RESULTS: A total of 17 patients were included. Eleven had a tracheostomy at initial management which consisted of 8 T-tubes and 9 strictly endoluminal stents placements. The main complications were minor aspirations in 5 patients (29%), granulation in 3 patients (18%), migration in 2 patients (12%), and severe dysphonia in 3 patients (18%). After a mean duration of 18.3 months, 11 patients (65%) had had their TSS definitely removed, 13 patients were tracheostomy free (76%), and a TSS remained in place in 4 patients (24%). CONCLUSIONS: Adult BLTS treatment with TSS placement is associated with low morbidity and excellent clinical outcomes, with a large proportion of patients free of airway instrumentation on long-term follow-up.

Multicenter study to assess endoscopic resection of 159 sinonasal adenocarcinomas.

PURPOSE: This study was designed to assess the efficacy and morbidity of the endoscopic endonasal approach for the treatment of sinonasal adenocarcinomas. METHODS: This was a retrospective, multicenter study of nine French tertiary referral centers, including untreated patients. All patients were operated by an endoscopic approach. Tumors were classified according to the UICC 2002. Demographic, therapeutic, histological, morbidity data, and the course of the disease were recorded. Survival rates were obtained using the Kaplan-Meier method. RESULTS: A total of 159 patients were included with a mean age of 69 years. There were 19T1, 62T2 (1M1), 36T3 (1N1), 26T4a, and 16T4b (1N2a-1N2c). The mean duration of hospitalization was 4.4 days. The histologic outcomes showed that the olfactory cleft, the posterior and anterior ethmoid sinus, and the sphenoid, maxillary, and frontal sinuses were invaded in 95, 64, 55, 19, 7, and 3 % of cases, respectively. Histologic margins were positive in 17 % (1T1, 4T2, 3T3, 2T4a, and 8T4b). In total, 130 patients received adjuvant radiotherapy on the primary tumor site (58 Gy), 24 cases were not irradiated, and 5 refused treatment. The mean follow-up was 32.5 ± 24 months. The complication rate was 19 %: 6 epistaxis, 3 meningitis, 6 CSF leaks, 2 dacryocystitis, and 8 septoplasties. The recurrence rate was 17.6 % (28 cases) within 23 ± 21 months. Eleven patients underwent a second surgical procedure. Nine patients died of their disease (3T2, 2T3, 4T4b). The global and disease-specific, recurrence-free survival rate at 3 years was 74 and 84 % respectively. CONCLUSIONS: The endoscopic approach seems to be efficient to remove sinonasal adenocarcinoma with low morbidity.

Endoscopic endonasal approach in the management of skull base chordomas--clinical experience on a large series, technique, outcome, and pitfalls.

Skull base chordomas represent very interesting neoplasms, due to their rarity, biological behavior, and resistance to treatment. Their management is very challenging. Recently, the use of a natural corridor, through the nose and the sphenoid sinus, improved morbidity and mortality allowing also for excellent removal rates. Prospective analysis of 54 patients harboring a skull base chordoma that were managed by extended endonasal endoscopic approach (EEA). Among the 54 patients treated (during a 72 months period), 21 were women and 33 men, undergoing 58 procedures. Twenty-two cases (40%) were recurrent and 32 (60%) newly diagnosed chordomas. Among the 32 newly diagnosed chordomas, a gross total resection was achieved in 28 cases (88%), a near total (>95% of tumor) in 2 cases (6%), a partial (>50% of tumor) in 2 cases (6%). Among the 22 recurrent chordomas, resection was complete in 7 cases (30%), near total in 7 (30%), and partial in 8 (40%). The global gross total resection rate was 65% (35/54 cases). Four patients (11%) recurred and 4 (11%) progressed within a mean follow-up of 34 months (range 12-84 months). Four patients (11%) were re-operated; one patient (1.8%) died due to disease progression, one patient (1.8%) died 2 weeks after surgery due to a massive bleeding from an ICA pseudo aneurysm. CSF leakage occurred in four patients (8%), and meningitis in eight cases (14%). No new permanent neurological deficit occurred. The EEA management of skull base chordomas requires a long and gradual learning curve that once acquired offers the possibility of either similar or better resection rates as compared to traditional approaches while morbidity is improved.

Double jeopardy, glomangiopericytoma and Glanzmann thrombasthenia resulting in recurrent epistaxis: a case report.

Glanzmann thrombasthenia is a rare bleeding disorder induced by inherited defects of the platelet membrane αIIbß3 glycoprotein. Glomangiopericytoma, on the other hand, is a very rare sinonasal tumor demonstrating a perivascular myoid phenotype. We herein report the first described case in the literature of Glanzmann thrombasthenia and glomangiopericytoma. The patient is a 40-year-old man diagnosed with type 1 Glanzmann thrombasthenia who presented with repetitive and profuse posterior epistaxis initially managed with platelet transfusions and recombinant activated factor VII (rFVIIa). Due to the unresolved epistaxis, nasal endoscopy was performed revealing a vascularized tumor. Subsequently, a sphenopalatine artery embolization followed by a surgical excision of the tumor was performed. The pathology report diagnosis of the tumor was glomangiopericytoma. This case sheds the lights on a very rare cause of epistaxis in a patient with Glanzmann thrombasthenia, with a challenging multidisciplinary management. A local cause of epistaxis should always be considered even in case of a diagnosed bleeding disorder, especially when the bleeding is recurrent.

The Prognostic Value of Olfactory Dysfunction in Patients with COVID-19: The COVIDORA Study.

BACKGROUND: Among all studies describing COVID-19 clinical features during the first wave of the pandemic, only a few retrospective studies have assessed the correlation between olfac-tory dysfunction (OD) and the evolution of disease severity. The main aim was to assess whether OD is a predictive factor of COVID-19 severity based on the patient's medical management (outpa-tient care, standard hospital admission, and ICU admission). METHODS: A national, prospective, mul-ticenter cohort study was conducted in 20 public hospitals and a public center for COVID-19 screen-ing. During the first wave of the pandemic, from 6 April to 11 May 2020, all patients tested positive for COVID-19 confirmed by RT-PCR underwent two follow-up ENT consultations within 10 days of symptom onset. The main outcome measures were the evolution of medical management (out-patient care, standard hospital admission, and ICU admission) at diagnosis and along the clinical course of COVID-19 disease. RESULTS: Among 481 patients included, the prevalence of OD was 60.7%, and it affected mostly female patients (74.3%) under 65 years old (92.5%), with fewer comor-bidities than patients with normal olfactory function. Here, 99.3% (290/292) of patients with OD presented with non-severe COVID-19 disease. Patients reporting OD were significantly less hospi-talized than the ones managed as outpatients, in either a standard medical unit or an ICU. Conclu-sions: As regards the clinical course of COVID-19 disease, OD could predict a decreased risk of hospitalization during the first wave of the pandemic.

Biomimetic Bilayered Scaffolds for Tissue Engineering: From Current Design Strategies to Medical Applications.

Tissue damage due to cancer, congenital anomalies, and injuries needs new efficient treatments that allow tissue regeneration. In this context, tissue engineering shows a great potential to restore the native architecture and function of damaged tissues, by combining cells with specific scaffolds. Scaffolds made of natural and/or synthetic polymers and sometimes ceramics play a key role in guiding cell growth and formation of the new tissues. Monolayered scaffolds, which consist of uniform material structure, are reported as not being sufficient to mimic complex biological environment of the tissues. Osteochondral, cutaneous, vascular, and many other tissues all have multilayered structures, therefore multilayered scaffolds seem more advantageous to regenerate these tissues. In this review, recent advances in bilayered scaffolds design applied to regeneration of vascular, bone, cartilage, skin, periodontal, urinary bladder, and tracheal tissues are focused on. After a short introduction on tissue anatomy, composition and fabrication techniques of bilayered scaffolds are explained. Then, experimental results obtained in vitro and in vivo are described, and their limitations are given. Finally, difficulties in scaling up production of bilayer scaffolds and reaching the stage of clinical studies are discussed when multiple scaffold components are used.

Endoscopic endonasal odontoidectomy for basilar invagination in children: Literature review and case report.

BACKGROUND: Basilar invagination (BI) is an uncommon clinical condition of the craniocervical junction (CCJ). Surgical management depends on 2 factors: mobility and reducibility; in cases of irreducible dislocation or persistent compression, odontoidectomy should be considered. CASE DISCUSSION: We present the case of a 13-year-old boy with severe BI, causing cervical myelopathy with progressive gait disorder. The patient underwent cervical traction followed by posterior decompression and occipitocervical fusion. Postoperatively, symptoms initially improved, until new neurological deterioraton set in 4 months later. Follow-up neuroimaging showed compression of the bulbo-medullary junction, with severe brainstem kinking and appearance of a cervical syrinx. Secondary surgery via an endoscopic endonasal approach (EEA) was deemed necessary to relieve the compression. Postoperative course was unremarkable, with steady clinical improvement and a return to independent activities of daily living within 6 months. LITERATURE REVIEW: A systematic literature review indicated that EEA conserves the palate and oropharynx mucosae, thus causing less airway and swallowing complications than the transoral approach. CONCLUSION: In selected cases with persistent anterior compression, odontoidectomy on EEA is a safe, effective and valid alternative for managing CCJ pathology.

Modification of macroporous titanium tracheal implants with biodegradable structures: tracking in vivo integration for determination of optimal in situ epithelialization conditions.

Previously, we showed that macroporous titanium implants, colonized in vivo together with an epithelial graft, are viable options for tracheal replacement in sheep. To decrease the number of operating steps, biomaterial-based replacements for epithelial graft and intramuscular implantation were developed in the present study. Hybrid microporous PLLA/titanium tracheal implants were designed to decrease initial stenosis and provide a surface for epithelialization. They have been implanted in New Zealand white rabbits as tracheal substitutes and compared to intramuscular implantation samples. Moreover, a basement membrane like coating of the implant surface was also designed by Layer-by-Layer (LbL) method with collagen and alginate. The results showed that the commencement of stenosis can be prevented by the microporous PLLA. For determination of the optimum time point of epithelialization after implantation, HPLC analysis of blood samples, C-reactive protein (CRP), and Chromogranin A (CGA) analyses and histology were carried out. Following 3 weeks the implant would be ready for epithelialization with respect to the amount of tissue integration. Calcein-AM labeled epithelial cell seeding showed that after 3 weeks implant surfaces were suitable for their attachment. CRP readings were steady after an initial rise in the first week. Cross-linked collagen/alginate structures show nanofibrillarity and they form uniform films over the implant surfaces without damaging the microporosity of the PLLA body. Human respiratory epithelial cells proliferated and migrated on these surfaces which provided a better alternative to PLLA film surface. In conclusion, collagen/alginate LbL coated hybrid PLLA/titanium implants are viable options for tracheal replacement, together with in situ epithelialization.

Collagen-based fibrillar multilayer films cross-linked by a natural agent.

Surface functionalization plays an important role in the design of biomedical implants, especially when layer forming cells, such as endothelial or epithelial cells, are needed. In this study, we define a novel nanoscale surface coating composed of collagen/alginate polyelectrolyte multilayers and cross-linked for stability with genipin. This buildup follows an exponential growth regime versus the number of deposition cycles with a distinct nanofibrillar structure that is not damaged by the cross-linking step. Stability and cell compatibility of the cross-linked coatings were studied with human umbilical vein endothelial cells. The surface coating can be covered by a monolayer of vascular endothelial cells within 5 days. Genipin cross-linking renders the surface more suitable for cell attachment and proliferation compared to glutaraldehyde (more conventional cross-linker) cross-linked surfaces, where cell clumps in dispersed areas were observed. In summary, it is possible with the defined system to build fibrillar structures with a nanoscale control of film thickness, which would be useful for in vivo applications such as inner lining of lumens for vascular and tracheal implants.

Percutaneous Cryoablation for Recurrent Head and Neck Tumors.

PURPOSE: To report techniques and results of 16 cryoablation procedures in 11 patients treated for recurrent head and neck cancer. METHODS AND MATERIALS: This retrospective study reviewed 11 consecutive patients with head and neck cancer recurrence after primary treatment by surgery and radiotherapy, treated with cryoablation between 2016 and 2020. Efficacy was measured by local control rate evaluated on MRI or/and PET. Tumor characteristics, number of cryoprobes, thermoprotective measures and complications were documented. RESULTS: Sixteen cryoablation procedures were performed in 11 patients with head and neck cancer recurrence after surgery or radiotherapy, deemed ineligible for classic salvage treatment. Among 11 patients, four were treated for an epidermoid carcinoma, four for an adenocarcinoma and three for other types: 1 muco-epidermoid carcinoma, 1 adenoid cystic carcinoma and 1 esthesioneuroblastoma, 10/11 patients had prior surgery, 7/11 patients had prior chemotherapy and 3/11 patients had prior radiotherapy. Median number of cryoprobes was 4, [IQR, 3-6 cryoprobes], thermoprotective measures to protect surrounding organs were required for 10/16 procedures. After cryoablation, local control rate was 45.4% at a mean follow-up of 11.7 months (range 3-34 months). Among the 16 cryoablation procedures, four resulted in complications, two were considered major complications: one septic shock on inhalation pneumopathy during extubation, requiring intensive care; and one dysphonia due to a recurrent nerve injury. CONCLUSION: Cryoablation as a salvage treatment for recurrence of head and neck tumors after surgery and/or radiotherapy is an effective option, especially for patients that cannot benefit from salvage surgery.

A Laboratory Investigation on a Tailored Skin and Muscle Flap Variant for the Retrosigmoid Approach.

Introduction An anatomical study was conducted to test a modified C-shaped flap designed for patients undergoing a keyhole approach and/or minicraniotomy for retrosigmoid approach (KRSA). Materials and Methods Ten heads specimens were used. The surgical technique investigated was based on a 4-cm C-shaped skin incision with medial convexity (placed 8 cm laterally to the external occipital protuberance, with the lower edge terminating 1.5 to 2 cm above the mastoid tip), which followed by careful subperiosteal dissection and completed by reflecting and securing the skin flap layer anteriorly and the muscle flaps superiorly and inferiorly by stitches. Anatomical findings, including depth of surgical corridor till to the cerebellopontine cistern (CPC) as well as the sparing of neurovascular structures, were evaluated in every specimen. Results Twenty surgical approaches to CPC were conducted, resulting in a short working distance to the target (32 mm) without any need for a self-retaining retractor. In every specimen, the integrity of occipital muscles and cutaneous nerves was maintained, and a solid multilayer closure was always achieved. These data suggest that landmarks-based design of this C-shaped incision could be helpful in avoiding damages to the soft tissues encountered during KRSA. Conclusion This modified approach provides a wide surgical corridor to access the CPC while ensuring the minimal invasiveness of the standard S-shaped incision. Compared with the latter, it preserves better the integrity of the surrounding soft tissues and appears less likely to cause any iatrogenic injury to occipital muscles and cutaneous nerves.