The Frontal Sinus and Frontal Recess: Anatomical, Radiological and Surgical Concepts

Abstract Introduction The frontal sinus (FS) is the most complex of the paranasal sinuses due to its location, anatomical variations and multiple clinical presentations. The surgical management of the FS and of the frontal recess (FR) is technically challenging, and a complete understanding of its anatomy, radiology, main diseases and surgical techniques is crucial to achieve therapeutic success. Objectives To review the FS and FR anatomy, radiology, and surgical techniques. Data Synthesis The FS features a variety of anatomical, volumetric and dimensional characteristics. From the endoscopic point of view, the FR is the point of greatest narrowing and, to have access to this region, one must know the anatomical limits and the ethmoid cells that are located around the FR and very often block the sinus drainage. Benign diseases such as chronic rhinosinusitis (CRS), mucocele and osteomas are the main pathologies found in the FS; however, there is a wide variety of malignant tumors that can also affect this region and represent a major technical challenge to the surgeon. With the advances in the endoscopic technique, the vast majority of diseases that affect the FS can be treated according to Wolfgang Draf, who systemized the approaches into four types (I, IIa, IIb, III). Conclusion Both benign and malignant diseases that affect the FS and FR can be successfully managed if one has a thorough understanding of the FS and FR anatomy, an individualized approach of the best surgical technique in each case, and the appropriate tools to operate in this region.

The Frontal Sinus and Frontal Recess: Anatomical, Radiological and Surgical Concepts.

Introduction The frontal sinus (FS) is the most complex of the paranasal sinuses due to its location, anatomical variations and multiple clinical presentations. The surgical management of the FS and of the frontal recess (FR) is technically challenging, and a complete understanding of its anatomy, radiology, main diseases and surgical techniques is crucial to achieve therapeutic success. Objectives To review the FS and FR anatomy, radiology, and surgical techniques. Data Synthesis The FS features a variety of anatomical, volumetric and dimensional characteristics. From the endoscopic point of view, the FR is the point of greatest narrowing and, to have access to this region, one must know the anatomical limits and the ethmoid cells that are located around the FR and very often block the sinus drainage. Benign diseases such as chronic rhinosinusitis (CRS), mucocele and osteomas are the main pathologies found in the FS; however, there is a wide variety of malignant tumors that can also affect this region and represent a major technical challenge to the surgeon. With the advances in the endoscopic technique, the vast majority of diseases that affect the FS can be treated according to Wolfgang Draf, who systemized the approaches into four types (I, IIa, IIb, III). Conclusion Both benign and malignant diseases that affect the FS and FR can be successfully managed if one has a thorough understanding of the FS and FR anatomy, an individualized approach of the best surgical technique in each case, and the appropriate tools to operate in this region.

Endoscopic Endonasal Transplanum Transtuberculum Approach for the Resection of a Large Suprasellar Craniopharyngioma.

Objectives To demonstrate an endoscopic endonasal transplanum transtuberculum approach for the resection of a large suprasellar craniopharyngioma. Design Single-case-based operative video. Setting Tertiary center with dedicated skull base team. Participants A 72-year-old male patient diagnosed with a suprasellar craniopharyngioma. Main Outcomes Measured Surgical resection of the tumor and preservation of the normal surrounding neurovascular structures. Results A 72-year-old male patient presented with a 1-year history of progressive bitemporal visual loss. He also referred symptoms suggestive of hypogonadism. Neurological examination was unremarkable and endocrine workup demonstrated mildly elevated prolactin levels. Magnetic resonance images demonstrated a large solid-cystic suprasellar lesion, consistent with the diagnosis of craniopharyngioma. The lesion was retrochiasmatic, compressed the optic chiasm, and extended into the interpeduncular cistern ( Fig. 1 ). Because of that, the patient underwent an endoscopic endonasal transplanum transtuberculum approach. 1 2 3 The nasal stage consisted of a transnasal transseptal approach, with complete preservation of the patient's left nasal cavity. 4 The cystic component of the tumor was decompressed and its solid part was resected. It was possible to preserve the surrounding normal neurovascular structures ( Fig. 2 ). Skull base reconstruction was performed with a dural substitute, a fascia lata graft, and a right nasoseptal flap ( Video 1 ). The patient did well after surgery and referred complete visual improvement. However, he also presented pan-hypopituitarism on long-term follow-up. Conclusions The endoscopic endonasal route is a good alternative for the resection of suprasellar lesions. It permits tumor resection and preservation of the surrounding neurovascular structures while avoiding external incisions and brain retraction. The link to the video can be found at: https://youtu.be/zmgxQe8w-JQ .

Comparison of three different adenoidectomy techniques in children - has the conventional technique been surpassed?

INTRODUCTION: Pharyngeal tonsil hyperplasia is the most frequent cause of nasal obstruction and chronic mouth breathing during childhood. Adenoidectomy is the procedure of choice for the resolution of these symptoms. It is not yet known, however, whether the conventional technique ("blind curettage") has been surpassed by more modern adenoidectomy techniques (video-assisted, with the aid of instruments). This study aimed to compare the conventional adenoidectomy technique with two other emerging techniques, performed in a reference otorhinolaryngology center. METHODS: This is a prospective and observational study of 33 children submitted to adenoidectomy using 3 different techniques that were followed up for a period of 3 months after surgery. The patients were divided into 3 different groups, according to the adenoidectomy technique: Group A (conventional technique - "blind curettage"); Group B (video-assisted adenoidectomy with microdebrider); Group C (video-assisted adenoidectomy with radiofrequency - Coblation®). The surgical time of each procedure was measured, being considered from the moment of insertion of the mouth gag until complete hemostasis was achieved. The questionnaire for quality of life OSA-18 was applied to all caregivers on the day of the surgery and 30-90 days after the procedure. Postoperative complications were also analyzed. RESULTS: For the entire patient sample, there was an improvement in quality of life after the surgery (p < 0.05). When analyzing the evolution of OSA-18 index, all groups showed statistically significant improvement, for all assessed domains. There were no statistically significant differences between the 3 techniques assessed for quality of life improvement after the surgery (p > 0.05). Regarding the duration of the procedure, the conventional technique showed the shortest surgical time when compared to the others (p < 0.05). No postoperative complications were noted, for any patient. CONCLUSIONS: The adenoidectomy resulted in improvement of quality of life, and there were no major postoperative complications, for all operated children, regardless of the technique used. The conventional technique was faster when compared to the more modern adenoidectomy techniques.

Endoscopic Endonasal Management of Skull Base Chordomas: Surgical Technique, Nuances, and Pitfalls.

Chordoma is a rare primary bone tumor derived from transformed notochord remnants. It has a local aggressive behavior and high recurrence rates. Treatment of skull base chordomas is complex and challenging. Control of the disease relies mainly on surgical excision of the tumor, sometimes followed by high-dose radiation therapy. The main surgical goal is to achieve maximal tumor removal with minimal morbidity. Development of the expanded endoscopic endonasal approach has improved surgical and prognostic results of skull base chordomas. This article highlights important aspects of approach selection, technique, and nuances of surgical management of this tumor.

Topical concentrated epinephrine (1:1000) does not cause acute cardiovascular changes during endoscopic sinus surgery.

BACKGROUND: Topical epinephrine is used in endoscopic sinonasal surgery for local vasoconstriction. Potential for cardiovascular complications remains a concern for some due to the possibility of systemic absorption. Topical vs injected epinephrine was examined in a prospective analysis of perioperative cardiovascular effects, and in an audit of cardiovascular complications during endoscopic sinonasal surgery. METHODS: A prospective cohort study of patients undergoing endoscopic sinonasal surgery was performed. Topical (1:1000) and injected (1:100,000) epinephrine were assessed. Cardiovascular outcomes of heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and electrocardiogram (ECG) changes were examined at baseline and minutely post-topical application (to 10 minutes) and postinjection (to 5 minutes). A retrospective assessment of cardiovascular events associated with a standardized regimen of topical (1:2000) and injected (1:100,000) epinephrine was performed. RESULTS: Nineteen patents were assessed (43.42 ± 15.90 years, 47.4% female) in the prospective analysis. Post-topical epinephrine, no significant changes occurred in any cardiovascular parameter. However, following injected epinephrine, changes in HR (59.53 vs 64.11 bpm, p < 0.001), SBP (96.16 vs 102.95 mmHg, p = 0.015), DBP (56.53 vs 60.74 mmHg, p = 0.019), and MAP (69.74 vs 74.81 mmHg, p = 0.002) occurred. On repeated-measures analysis of variance (ANOVA) all parameters were significantly affected by injection. No ECG abnormalities were seen in either topical or injection phases. The retrospective analysis of 1260 cases identified 2 cases of cardiovascular complications (0.16%), both relating to injected epinephrine. CONCLUSION: Combination topical (1:1000 to 1:2000) and injectable (1:100,000) epinephrine is safe for use in endoscopic sinonasal surgery. Injection resulted in the cardiovascular changes and accounted for the cardiovascular events reported.

Endoscopic Endonasal Approach in Skull Base Chondrosarcoma Associated with Maffucci Syndrome: Case Series and Literature Review.

BACKGROUND: Maffucci syndrome is a nonhereditary disorder in which patients develop multiple enchondromas and cutaneous, visceral, or soft tissue hemangiomas. The potential malignant progression of enchondroma into a secondary chondrosarcoma is a well-known fact. Nevertheless, chondrosarcoma located at the skull base in patients with Maffuci syndrome is a very rare condition, with only 18 cases reported in the literature. CASE DESCRIPTION: We report 2 other cases successfully treated through an expanded endoscopic endonasal approach and discuss the condition based on the literature review. CONCLUSIONS: Skull base chondrosarcoma associated with Maffucci syndrome is a rare condition. The disease cannot be cured, therefore surgical treatment should be performed in symptomatic patients aiming for maximal tumor resection with function preservation. The endoscopic endonasal approach is a safe and reliable alternative for the management of these tumors.

Endoscopic Endonasal Approach to Ventral Posterior Fossa Meningiomas: From Case Selection to Surgical Management.

Clival, petroclival, and foramen magnum meningiomas are challenging lesions to manage independently of the selected surgical approach. The expanded endoscopic endonasal approach (EEA) provided a safe alternative on the armamentarium of skull base approaches. There is a paucity of literature regarding endoscopic management of meningiomas because of certain limiting factors, including rarity of the pathologic condition, technical challenges, expertise of the surgical team, and available resources. The surgical technique, possible complications, and postoperative care are described in detail. This article highlights the important aspects in choosing this surgical approach and managing ventral posterior fossa meningiomas through the EEA.

Endoscopic combined "transseptal/transnasal" approach for pituitary adenoma: reconstruction of skull base using pedicled nasoseptal flap in 91 consecutive cases.

OBJECTIVE: The purpose of this study was to describe the endoscopic combined "transseptal/transnasal" approach with a pedicled nasoseptal flap for pituitary adenoma and skull base reconstruction, especially with respect to cerebrospinal fluid (CSF) fistula. METHOD: Ninety-one consecutive patients with pituitary adenomas were retrospectively reviewed. All patients underwent the endoscopic combined "transseptal/transnasal" approach by the single team including the otorhinolaryngologists and neurosurgeons. Postoperative complications related to the flap were analyzed. RESULTS: Intra- and postoperative CSF fistulae were observed in 36 (40%) and 4 (4.4%) patients, respectively. Among the 4 patients, lumbar drainage and bed rest healed the CSF fistula in 3 patients and reoperation for revision was necessary in one patient. Other flap-related complications included nasal bleeding in 3 patients (3.3%). CONCLUSION: The endoscopic combined "transseptal/transnasal" approach is most suitable for a two-surgeon technique and a pedicled nasoseptal flap is a reliable technique for preventing postoperative CSF fistula in pituitary surgery.

Endoscopic combined “transseptal/transnasal” approach for pituitary adenoma: reconstruction of skull base using pedicled nasoseptal flap in 91 consecutive cases / O acesso endoscópico transeptal/transnasal em cirurgias de resseção de adenoma de hipófise: reconstrução da base do crânio combinado com a criação do flap naso-septal pediculado em 91 pacientes consecutivos

Objective The purpose of this study was to describe the endoscopic combined “transseptal/transnasal” approach with a pedicled nasoseptal flap for pituitary adenoma and skull base reconstruction, especially with respect to cerebrospinal fluid (CSF) fistula.Method Ninety-one consecutive patients with pituitary adenomas were retrospectively reviewed. All patients underwent the endoscopic combined “transseptal/transnasal” approach by the single team including the otorhinolaryngologists and neurosurgeons. Postoperative complications related to the flap were analyzed.Results Intra- and postoperative CSF fistulae were observed in 36 (40%) and 4 (4.4%) patients, respectively. Among the 4 patients, lumbar drainage and bed rest healed the CSF fistula in 3 patients and reoperation for revision was necessary in one patient. Other flap-related complications included nasal bleeding in 3 patients (3.3%).Conclusion The endoscopic combined “transseptal/transnasal” approach is most suitable for a two-surgeon technique and a pedicled nasoseptal flap is a reliable technique for preventing postoperative CSF fistula in pituitary surgery.

Objetivo O objetivo deste estudo foi descrever o acesso endoscópico transeptal/transnasal combinado com a criação do flap naso-septal pediculado para reconstrução da base do crânio em cirurgias de resseção de adenoma de hipófise, especialmente nos casos que ocorrem fístula líquido cefalorraquidiano (FLC).Método Noventa e um pacientes consecutivos portadores de adenoma de hipófise foram retrospectivamente revisados. Complicações pós-operatórias relacionadas ao flap foram analisadas.Resultados Fístulas líquido cefalorraquidiano intra e pós-operatórias foram observadas em 36 (40%) e 4 (4,4%) dos pacientes, respectivamente. Entre os 4 pacientes, drenagem lombar e repouso absoluto foram suficientes para o fechamento da fístula e intervenção cirúrgica foi necessária em apenas um paciente. Outra complicação relacionada ao flap foi o sangramento em 3 (3,3%) dos pacientes.Conclusão O acesso endoscópico transeptal/transnasal combinado é melhor aplicado quando realizado por dois cirurgiões e o flap naso-septal é uma técnica eficaz para prevenção de fístula pós-operatória em cirurgias de hipófise.

A modified combined transseptal/transnasal binostril approach for pituitary lesions in patients with a narrow nasal space: technical note.

We describe a modification of the combined transseptal/transnasal binostril approach using a two-surgeon, four-handed technique (modified Stamm's approach) for pituitary lesions in patients with narrow nasal spaces. This approach comprises of a transseptal route through one nostril and a transnasal route without harvesting a pedicled nasoseptal flap (NSF) through the other. On the transseptal side, the nasal septum was removed using an endoscopic septoplasty technique. On the transnasal side, the mucosa containing the septal branch of the sphenopalatine artery over the face of the sphenoid and nasal septum was preserved for harvesting the NSF if an intraoperative cerebrospinal fluid leak was encountered. This approach was performed in six patients with pituitary lesions, including four non-functioning macroadenomas, one growth hormone-producing macroadenoma, and one Rathke's cleft cyst, all of which were associated with a severe deviation of the nasal septum and/or narrow nasal space. The meticulous and comfortable manipulation of an endoscope and instruments were achieved in all six patients without surgical complications. Our findings, although obtained in a limited number of cases, suggest that the modified Stamm's approach may be useful for selected patients, particularly those with a severe deviation of the nasal septum, without considerable damage to the nasal passages.

Craniopharyngioma.

Craniopharyngiomas are rare epithelial tumors arising along the path of the craniopharyngeal duct; therefore, they occur in the sellar or suprasellar regions. These tumors commonly lead to neurologic, endocrinological, or visual symptoms. Radical surgery is the treatment of choice in craniopharyngiomas. The transnasal/transsphenoidal endoscopic approach offers the possibility of removing the tumor without retracting brain and optic pathways, with good results. The rate of cerebrospinal fluid fistula has improved due to the use of vascularized mucosal flaps for cranial base reconstruction.

Case studies in the surgical management of pediatric nasal airway obstruction.

The authors present two case studies on pediatric nasal obstruction that highlight the consequences of a delayed diagnosis and the complexities of managing obstructed lesions in children.

Novel compact laptop-based image-guidance system: preliminary study.

OBJECTIVES: To describe a novel portable laptop-based image-guidance system and its preliminary navigational results. METHODS: An optic-based, specially developed navigational system and a life-size endoscopic sinus anatomic model were used. The model was submitted to computer tomography (CT), and predefined anatomic landmarks were used to test the image-guidance accuracy according to the real model. RESULTS: All anatomic landmarks were identified by the image-guidance system and all matched with endoscopic or eye views. CONCLUSIONS: This novel compact navigation device was shown to be fast and reliable. A larger series, involving more models, cadavers, and patients, with the evaluation of multiple anatomic points needs to be done before we can reliably determine the overall accuracy of this novel device. However, this new system is promising, and in the future it can be part of the armamentarium of otolaryngologists' personal equipment in order to perform low-cost image-guided surgeries in different places with the same equipment.

Closure of large skull base defects after endoscopic transnasal craniotomy. Clinical article.

OBJECT: The authors describe the utility of and outcomes after endoscopic transnasal craniotomy and skull reconstruction in the management of skull base pathologies. METHODS: The authors conducted a observational study of patients undergoing totally endoscopic, transnasal, transdural surgery. The patients included in the study underwent treatment over a 12-month period at 2 tertiary medical centers. The pathological entity, region of the ventral skull base resected, and size of the dural defect were recorded. Approach-related complications were documented, as well as CSF leaks, infections, bleeding-related complications, and any minor complications. RESULTS: Thirty consecutive patients were assessed during the study period. The patients had a mean age of 45.5 +/- 20.2 years and a mean follow-up period of 182.4 +/- 97.5 days. The dural defects reconstructed were as large as 5.5 cm (mean 2.49 +/- 1.36 cm). One patient (3.3%) had a CSF leak that was managed endoscopically. Two patients had epistaxis that required further care, but there were no complications related to intracranial infections or bleeding. Some minor sinonasal complications occurred. CONCLUSIONS: Skull base endoscopic reconstructive techniques have significantly advanced in the past decade. The use of pedicled mucosal flaps in the reconstruction of large dural defects resulting from an endoscopic transnasal craniotomy permits a robust repair. The CSF leak rate in this study is comparable to that achieved in open approaches. The ability to manage the skull base defects successfully with this approach greatly increases the utility of transnasal endoscopic surgery.

Endoscopic transnasal craniotomy and the resection of craniopharyngioma.

OBJECTIVES/HYPOTHESIS: To describe the utility of a large transnasal craniotomy and its reconstruction in the surgical management of patients with craniopharyngioma. STUDY DESIGN: Observational retrospective cohort study. METHODS: Retrospective review of patients treated in an academic neurosurgery/rhinology practice between 2000 and 2007. Patient characteristics (age, sex, follow-up), tumor factors (size, position extension, previous surgery), type of repair (pedicled mucosal flaps, free mucosal grafts), and outcomes (visual, endocrine, and surgical morbidity) were defined and sought in patients who had an entirely endoscopic resection of extensive craniopharyngioma (defined as requiring removal of the planum sphenoidale in addition to sella exposure in the approach). RESULTS: Seven patients had an entirely endoscopic resection of extensive craniopharyngioma during the study period. Mean age was 23.4 years (standard deviation +/- 16.3). Mean tumor size was 3.2 cm (standard deviation +/- 2.0). The majority of these pathologies had extensive suprasellar disease, and two (28.6%) had ventricular disease. Cerebrospinal fluid leak rate was 29% (2 of 7). These leaks occurred only in reconstructions with free mucosal grafts. There were no cerebrospinal fluid leaks in patients who had vascularized pedicled septal flap repairs. CONCLUSIONS: The endoscopic management of large craniopharyngioma emphasizes recent advancements in endoscopic skull base surgery. The ability to provide exposure through a large (4 cm+) transnasal craniotomy, near-field assessment of neurovascular structures, and the successful reconstruction of a large skull defect have significantly advanced the field in the past decade. The use of a two-surgeon approach and bilateral pedicled septal mucosal flaps have greatly enhanced the reliability of this approach.