Posterior Table Of Frontal Sinus Research Articles

Single surgeon experience with minimally invasive supraorbital craniotomy versus bifrontal craniotomy for anterior skull base meningiomas.

Background: Anterior skull base meningiomas (ASBMs) account for about 10% of meningiomas. Bifrontal craniotomy (BFC) represents the traditional transcranial approach to accessing meningiomas in these locations. Supraorbital craniotomy (SOC) provides a minimally invasive subfrontal corridor in select patients. Here, we present our series of ASBM accessed by SOC and BFC by a single surgeon to review decision-making and compare outcomes in both techniques.Methods: Thirty-three patients were identified with ASBM. Age, tumor characteristics, presenting symptoms, postoperative complications, and outcomes were analyzed.Results: Bifrontal and SOC were performed in 13 and 20 patients, respectively. Mean follow-up time was 98.4 months. Patients undergoing SOC had smaller tumor size, located farther from the posterior table of frontal sinus, had less peritumoral edema, and decreased length of stay compared to patients undergoing BFC. Extent of resection was slightly better with BFC (99.8%) compared to SOC (91.8%), although this difference did not reach statistical significance. Recurrence-free survival and rate of re-do surgeries were not different between two groups. BFC was associated with higher rates of postoperative encephalomalacia.Conclusion: SOC provides an excellent surgical option for ASBMs providing comparable extent of resection, minimal manipulation of brain, and excellent cosmetic outcomes for patients. The patient selection is key to maximize the benefits from this approach.

Fronto-ethmoidal Mucocele with Frontal Sinus Destruction

Fronto ethmoidal mucocele is a benign but expansive pseudo cyst due to mucous secreting nature of fronto-ethmoid sinus. A rare presentation of frontoethmoidal mucocele was reported. Our subject a 61 years old female presented with frontoethmoidal mucocele of unusually large size and two in number which developed over 2 years. Two masses one above left supra-orbital region and next on forehead was noted along with diplopia and non-axial proptosis in left eye due to swelling. Similar findings were found on CT scan and diagnosis was confirmed during surgery. Endoscopic marsupialisation of fronto-ethmoid pyocele with incision & drainage of isolated pyocele in the frontal bone was performed under general anaesthesia. A puncture wound in the posterior table of frontal sinus which might have resulted in CSF rhinorrhoea was dealt at the same setting. Keywords: Fronto-ethmoidal mucocele, diplopia, two mucocele, CSF rhinorrhoea

Frontal Sinusitis and Nasocutaneous Fistula as Complication of Frontal Sinus Posterior Table Fracture

Frontal Sinusitis and Nasocutaneous Fistula as Complication of Frontal Sinus Posterior Table Fracture

Letter to the Editor: In Response to "Minimally Invasive Technique for Repairing CSF Leaks Due to Defects of Posterior Table of Frontal Sinus".

We recently reviewed the article “Minimally Invasive Technique for Repairing CSF Leaks Due to Defects of Posterior Table of Frontal Sinus” by Bhavana et al.1 The authors present a technique of repairing traumatic cerebrospinal fluid (CSF) leaks of the posterior table through a frontal trephine and then use an endoscope to visualize and repair the defect using fat, cartilage, fascia lata, and fibrin glue as an alternative to the conventional approach of obliteration of the frontal sinus. They demonstrated that at a mean follow-up of 1 year, no patients had a CSF leak recurrence, and there was minimal morbidity (neuralgic pain and hypertrophic scar).

Response to the Letter to the Editor regarding "Minimally Invasive Technique for Repairing CSF Leaks Due to Defects of Posterior Table of Frontal Sinus".

Response to the Letter to the Editor regarding "Minimally Invasive Technique for Repairing CSF Leaks Due to Defects of Posterior Table of Frontal Sinus".

Preservation of Functioning Sinus in Frontal Sinus Posterior Table Fractures

Objective: Sinus preservation after posterior table frontal fractures (PTFF) may be preferable to obliteration/cranialization for minimizing risk of mucocele. This study assessed functional outcomes and complications after open reduction and internal fixation (ORIF) with sinus preservation for PTFF. Study Design: Consecutive case series. Patients and Methods: Patients with PTFF undergoing ORIF with sinus preservation from July 2012 to December 2013 were assessed. Fracture type/extent, presence/extent of dural injury, and cerebrospinal fluid (CSF) leak were recorded. Type of frontal sinusotomy, use of frontal stents, and lumbar drain were recorded. Outcomes evaluated were CSF leak closure, incidence of perioperative meningitis and frontal patency. Results: For two patients with intact dura and no CSF leak, displaced fragments were removed without dural repair. For one patient with CSF leak, a 1 cm dural defect was associated with comminuted PTFF; two-layered closure with underlay Duragen sheet and pericranial flap (PF) was performed. Lumbar drainage was not used. In two patients, Draf 2a frontal sinusotomy was performed with silastic stenting for 3 weeks. Frontal sinuses were aerated with widely patent frontal recess in all cases with no postoperative CSF leak, meningitis or cranial prolapse at mean 14.0 ± 5.0 months. Conclusion: Preservation of frontal sinus is an option for selected PTFF cases. Dural graft plus vascularized PF without a rigid layer may be used for frontal sinus CSF leak repair.

Minimally Invasive Technique for Repairing CSF Leaks Due to Defects of Posterior Table of Frontal Sinus.

Objective Cerebrospinal fluid (CSF) leaks from the frontoethmoid and sphenoid region can be easily dealt with endoscopic approaches, but CSF rhinorrhea due to frontal sinus fractures are difficult to treat solely by the nasal endoscopic approach and may require external repair. The technique described targets defects of the posterior table of the frontal sinus where conventional osteoplastic approach of obliteration is usually done. This technique is minimally invasive and involves repair using an endoscope via a frontal trephine. Methods We have treated five cases of traumatic CSF rhinorrhea with this technique, and the mean follow-up is 1 year (range: 10-14 months). The frontal sinus is opened by making a small stab incision (frontal trephine), and the defect site is localized by visualization via endoscope through the trephine. The repair is then performed with fat, bone graft, and fibrin glue. Results Closure of the defect was achieved in a single stage in all the patients, and none of them had a recurrence of leak in the 1-year follow-up period. Conclusion This is a good technique for superiorly and laterally placed posterior table defects of the frontal sinus with minimal morbidity and excellent closure rates.

Modified subtotal‐Lothrop procedure for extended frontal sinus and anterior skull‐base access: a case series

The endoscopic modified Lothrop procedure (EMLP) is well established for resistant frontal sinus disease and anterior skull base (ASB) exposure. However, this technique may be unnecessarily aggressive by removing avoidable sinonasal structures in select cases. Previously, in a cadaveric study, we proposed a modification of the EMLP, termed the modified subtotal-Lothrop procedure (MSLP), to access the ASB and to address complex frontal sinus disease, for which access to the bilateral frontal sinus posterior table is required. This study provides a step-by-step description of this technique, and presents our experience in 5 patients who underwent this approach. A retrospective analysis was performed at a tertiary referral center on all patients undergoing endoscopic ASB resection and complex frontal sinus surgeries between May 2011 and May 2013. Of 8 patients identified who underwent an MSLP, 5 had at least 1-year follow-up. All patients underwent successful ASB exposure via the MSLP without complications and preservation of one frontal sinus recess. Adequate access to the bilateral posterior frontal sinus table was achieved in all cases. A patent frontal sinus drainage pathway could be assessed endoscopically after a mean follow-up of 18.6 (range, 12-27) months. The MSLP is a feasible approach for exposure of the ASB and accessing complex frontal sinus pathology. This modification provides adequate ASB exposure and surgical maneuverability similar to the EMLP, while preserving one frontal sinus recess. This modification was successful in providing adequate exposure and maneuverability as well as maintaining frontal sinus patency in this small cohort.

Frontal Meningoencephalocele: Changing Trends

ABSTRACT Frontal sinus defects involving the posterior table has always been challenging for the otolaryngologists. It traditionally involved open approaches like osteoplastic approach for the repair of defects or fractures involving the posterior table of frontal sinus. Better instrumentation, technique, and experience have increased the feasibility of endoscopic repair of frontal sinus skull-base defects. With the increased possibilities of endoscopic approach and instrumentation for the frontal sinus, an endoscopic repair of a posterior table defect with a meningoencephalocele in a long standing post-traumatic case has been described. How to cite this article Gupta AK, Patro SK, Nabh V. Frontal Meningoencephalocele: Changing Trends. Clin Rhinol An Int J 2014;7(3):125-129.

Chapter 1: Sinonasal anatomy and function.

An understanding of paranasal sinus anatomy based on important fixed landmarks rather than variable anatomy is critical to ensure safe and complete surgery. The concept of the paranasal surgical box defines the anatomic limits of dissection. The boundaries of the surgical box include the middle turbinate medially, orbital wall laterally, and skull base superiorly. The "vertical component" of the surgical box defines the boundaries of the frontal recess and includes the middle turbinate and intersinus septum medially, medial orbital wall and orbital roof laterally, nasofrontal beak anteriorly, and skull base and posterior table of frontal sinus posteriorly. The paranasal sinuses are divided into anterior, posterior, and sphenoidal functional cavities based on their distinct drainage pathways into the nose. The ultimate goal of surgery is to create a functional sinus cavity. Application of the paranasal surgical box and its vertical component enables the surgeon to view the limits of dissection with a single position of the endoscope. This will ensure complete dissection of the functional sinonasal compartments and effectively avoid leaving behind disconnected cells from the surgical cavity, mucocele formation, mucous recirculation, overcome obstructive phenomenon and enable maximal delivery of topical therapy in the post-operative setting. This article reviews the structure and function of the nasal cartilages and turbinates. It also describes the concept of the paranasal surgical box, key anatomical landmarks and limits of dissection. Normal anatomy and common variants of normal anatomy are discussed.

Modified Subtotal Lothrop Procedure for Extended Frontal Sinus and Anterior Skull Base Access: A Cadaveric Feasibility Study with Clinical Correlates

Objective The endoscopic modified Lothrop procedure (EMLP) is an established approach for recalcitrant frontal sinus disease and anterior skull base exposure. However, in select cases, this technique may involve unnecessary resection of sinonasal structures. In this study, we propose a modification of the EMLP, termed the modified subtotal-Lothrop procedure (MSLP), to access the anterior skull base and complex frontal sinus disease for which access to the bilateral frontal sinus posterior table is required. Methods A cadaveric dissection with photo documentation was performed at an academic medical center on four cadaver heads using standard endoscopic techniques to demonstrate the MSLP and its feasibility. Results The endoscopic MSLP allowed ample access for instrumentation in each of the dissections using a 30- or 70-degree endoscope. Adequate bilateral access to the posterior table of the frontal sinus was gained in all cases without the need for dissection of the contralateral frontal sinus recess (FSR). Conclusion The MSLP appears to be a feasible technique for exposure of the anterior skull base and accessing complex frontal sinus pathology. This modification provides similar anterior skull base exposure and surgical maneuverability as the EMLP while limiting surgical dissection to one FSR, thereby preserving as much of the natural mucociliary drainage pathways as possible.

Transnasal Endoscopic Repair of Posterior Table Fractures

Conventional treatment of frontal sinus posterior table fractures has included osteoplastic flap or cranialization procedures despite considerable advances in endoscopic technique and experience. The objective of the current study was to evaluate outcomes of frontal sinus fractures involving the posterior table managed using endoscopic approaches. Prospective cohort. Tertiary care, academic university hospital. Prospective evaluation of patients with posterior table fractures was performed. Data were collected regarding demographics, etiology, technique, operative site, length involving the posterior table, size of the skull base defect, complications, and clinical follow-up. Thirteen patients (average age 37 years) with posterior table fractures were treated using endoscopic techniques from 2008 to 2012. Mean follow-up time was 68 weeks (range, 2-206 weeks). Patients were primarily managed using Draf IIb frontal sinusotomies with 1 individual requiring a concomitant trephine. A Draf III procedure was performed in 1 patient. Average fracture defect (length vs width) was 13 × 4.5 mm, and average length involving the posterior table was 9.7 mm (1-30 mm). Skull base defects were covered with a septal flap and/or free tissue grafts. Although 1 individual required a revision frontal sinusotomy and follow-up was short in several patients, all sinuses remained patent on last clinical examination. Management of frontal sinus posterior table fractures using minimally invasive endoscopic techniques provides excellent outcomes in selected cases. Fractures of up to 30 mm in length were adequately managed in this series and indicate this approach can be a viable alternative in the treatment of these fractures.

Rotation Flaps after Draf Procedures: A Cadaver Study

Objective: To describe the anatomy and application of local mucosal flaps to reduce cicatricial scarring of the frontal recess after Draf IIB and Draf III procedures. Method: Description and illustration of the surgical technique of 2 local mucosal flaps after Draf IIB and III procedures in a cadaveric model. Results: Two distinct local rotation flaps can be successfully used after Draf IIB and Draf III procedures. 1) Prior to superior middle turbinectomy, a medially based mucosal flap is elevated from the medial aspect of the middle turbinate to the nasal septum. This flap is then placed on the posteromedial raw bone of the frontal recess after the Draf IIB. 2) Bilateral posteriorly based flaps are elevated off of the anterosuperior septum prior to the septectomy in a Draf III procedure. After the drillout is performed, the mucosal flaps are rotated to cover the frontal sinus posterior table. Conclusion: Use of local mucosal flaps to provide primary healing after Draf IIB and Draf III procedures is technically feasible and may decrease the risk of restenosis after frontal sinus surgery.

Endoscopic Management of Frontal Sinus Fractures

Objective: Conventional treatment of frontal sinus posterior table fractures has included osteoplastic flap or cranialization procedures despite considerable advances in endoscopic technique and experience. The objective of the current study was to evaluate outcomes of frontal sinus fractures involving the posterior table managed using endoscopic approaches. Method: Retrospective evaluation of patients with posterior table fractures was performed at the University of Alabama at Birmingham from January 2008 through December 2011. Data were collected regarding demographics, etiology, technique, operative site, length involving the posterior table, size of the skull base defect, complications, and clinical follow up Results: Eleven patients (age 39 ± 5 years) with posterior table fractures were treated using endoscopic techniques from 2008-2011. Mean follow-up time was 44 ± 15 weeks (range 2-164). Patients were primarily managed using Draf IIb frontal sinusotomies with 1 individual requiring a concomitant trephine. A Draf III procedure was performed in 1 patient. Average fracture defect (length vs width) was 13.5 3.6 mm and the average length involving the posterior table was 9.6 mm (1-30 mm). Skull base defects were covered with a septal flap and/or Surgisus tissue grafts. One patient referred after failed cranialization was endoscopically obliterated. Although 1 individual required a revision frontal sinusotomy, all sinuses remain patent on last follow-up. Conclusion: Management of frontal sinus posterior table fractures using minimally invasive endoscopic techniques provides excellent outcomes in selected cases. Posterior table fractures of up to 30 mm in length were adequately managed in this series and indicate this approach should become an active part of the treatment algorithm.

Anatomical and technical correlates in endoscopic anterior skull base surgery: A cadaveric analysis

Objective The objectives of this study were to 1) evaluate anatomical relationships and 2) develop technical correlates for endoscopic anterior skull base (ASB) surgery. Study Design Cadaver study. Setting Minimally invasive surgery laboratory. Subjects and Methods Ten adult fresh-frozen cadaver heads were dissected from December 2006 to December 2007. The endoscopic trans-cribriform, trans-ethmoid approach to the anterior cranial base was refined over these consecutive dissections. Endoscopic orientation along the ventral axis was assessed with 0°, 30°, and 70° rigid telescopes. Anatomical dimensions of the ASB window were measured in the anteroposterior (posterior table of frontal sinus to planum sphenoidale) and transverse (orbit-to-orbit) dimensions at the anterior ethmoid artery (AEA) and posterior ethmoid artery (PEA). Results Endoscopic cadaveric dissections confirmed technical feasibility of ASB surgery and greatly enhanced understanding of ASB anatomical concepts. The 30° rigid endoscope provided the most optimal view from the frontal sinus to the planum sphenoidale with the least distortion, relative to 0° and 70° scopes. Careful identification of the AEA and PEA was requisite for proper orientation at the ASB. The posterior one third of the ASB was thickest and always required drilling for resection. The mean boundaries of the ASB window were 33.7 mm (anterior to posterior) and 23.5 and 19.1 mm at the AEA and PEA (orbit to orbit), respectively. Conclusion This prospective cadaveric study outlined key correlates for endoscopic ASB surgery. It serves to highlight the requisite technical steps and anatomical dimensions when the trans-nasal endoscopic route is employed for ASB pathology.

Endoscopic repair of skull base defects presenting with pneumocephalus.

Persistent pneumocephalus often indicates the presence of a skull base (SB) defect associated with one of the paranasal sinuses. Such defects require treatment to avoid sequelae. The study objective was to evaluate success in endoscopic closure of SB defects associated with pneumocephalus. Retrospective medical record review. Tertiary care academic rhinology practice. A 5-year retrospective review of patients presenting with pneumocephalus. Presenting symptoms, etiology of SB defects, radiologic findings, operative techniques, and follow-up were evaluated. Success of endoscopic SB defect repair in the setting of pneumocephalus was assessed. Factors potentially contributing to failure were evaluated in appropriate cases. Eleven patients with pneumocephalus from 14 SB defects underwent 17 endoscopic repairs. In 11 surgical procedures, active cerebrospinal fluid (CSF) leaks were identified, but in the remaining 6, pneumocephalus was present without CSF leak. Radiologic location of pneumocephalus ranged from extra-axial to diffuse within the brain parenchyma. SB defects were identified using fine-cut computed tomographic (CT) scans, CT cisternograms, and intrathecal fluorescein. Defects were located in the sphenoid, sella, ethmoid roof, and frontal sinus posterior table. Eight of 11 patients (72%) were managed with endoscopic repair alone. Factors potentially affecting failure included malignancy, previous radiation, intracranial infection, malnutrition, and Cushing disease. Endoscopic SB defect repair for pneumocephalus is largely successful. Localization of SB defects in these cases is often assisted by CT cisternography and intrathecal fluorescein.