Anatomic misconceptions regarding the agger nasi cell: A preliminary analysis utilizing endoscopic anatomic dissection and three-dimensional computed tomography.

The agger nasi cell is a key anatomic landmark in endoscopic frontal sinus surgery. However, discord amongst authors regarding anatomic definition and prevalence raises questions of its suitability as a surgical landmark. The purpose of this investigation is to evaluate the agger nasi cell using radiographic imaging correlated with endoscopic anatomic dissection to consider the cell's role as a surgical landmark and to explore if three-dimensional computed tomography (3D-CT) technology can provide enhanced insight into this anatomy. CT scans of 11 cadaveric sinonasal complexes were studied using triplanar CT or 3D-CT scanning with stereoscopic 3D imaging. Endoscopic dissections were performed and video recorded. Attention was given to identify agger nasi pneumatization and its origin. Pneumatization of the agger nasi region was noted in 4/11 cases (36.4%) (in two cases the pneumatization arose from the frontal recess, in two from a true agger nasi cell). The agger nasi region appeared as solid unpneumatized bone in 4/11 cases (36.4%). In 3/11 cases (27.3%) limited pneumatization was noted, bordering on but not pneumatizing the agger nasi proper. It may be confusing for otolaryngologic surgeons in training to rely on the "agger nasi cell" as a surgical landmark due to misconceptions regarding the anatomy, prevalence and anatomic definitions. Using standard CT scans to teach anatomy may have shortcomings as compared to the gold standard of surgical dissection. However, new 3D-CT holds promise to more accurately reflect small microanatomic features and provide an improved road map of a patient's anatomy in surgery.

Anosmia following middle nasal concha resection: An anatomic and developmental review with clinical correlation.

Losing the sense of smell can be associated with a significant decrease in quality of life. Fortunately, this occurs infrequently with modern paranasal sinus surgery that has stressed minimally invasive, tissue-sparing principles. However, over time, more extensive surgical applications have emerged that incorporate increased tissue removal. Post-operative period sequelae can occur, including anosmia. Understanding the potential implications of expanded tissue removal, such as middle nasal concha (turbinate) resection, is clinically important and is facilitated by an understanding of anatomy. Our understanding of anatomic nuances is enhanced through an appreciation of embryonic and fetal development. We herein review the developmental anatomy of the middle nasal concha of the ethmoid sinus and olfactory nerve area as it relates to middle nasal concha removal during endoscopic sinus surgery. We present images from our analysis of 12 embryonic and fetal specimens that highlight the important relationship between the middle nasal concha and olfactory nerves. We also review the clinical issues surrounding turbinate preservation versus resection and present a clinical correlation to underscore the uncommon but significant complication of anosmia following sinus surgery with middle nasal concha resection. We highlight knowledge gaps, discuss case selection and review surgical technique modifications for middle nasal concha surgery to reduce the chance of this complication in the future.

The Ponticulus Ethmoidalis: A Newly Appreciated Anatomic Landmark in Endoscopic Sinus Surgery.

INTRODUCTION: Ethmoid sinus anatomy is so variable it has been referred to as a "labyrinth." Accordingly, this provides a challenge for surgeons performing ethmoidectomy. Identifying consistent anatomic features or landmarks within the ethmoid sinus can aid surgeons performing sinus surgery. The goal of this investigation was to determine if subtle anatomic features are consistently present within the retrobullar recess and could potentially serve as a reliable landmark for surgeons performing ethmoid surgery. MATERIALS AND METHODS: Ethmoid sinus anatomy was studied in 60 sinonasal complexes through several methods including gross anatomic dissection, endoscopic dissection and 3-D CT stereoscopic imaging. RESULTS: Review of gross sagittal sinonasal specimens revealed that the retrobullar recess was present in all specimens and a tissue bridge was noted emanating from the basal lamella deep within the retrobullar recess in 23/24 gross sagittal specimens; in 1/24 specimens it was quite small or difficult to appreciate. In the radiographic analysis, the tissue bridge was noted in 17/18, in 1/18 it was not appreciated. In the endoscopic dissections it was noted in 17/18, in 1/18 it was small or not appreciated. CONCLUSION: The small tissue bridge, or ponticulus within the retrobulbar recess was seen in nearly all ethmoid sinuses studied leading us to venture that could be used in surgery to orient surgical dissection through the basal lamella into the posterior ethmoid region.

The Anterior Ethmoidal "Genu": A Newly Appreciated Anatomic Landmark for Endoscopic Sinus Surgery.

Human sinonasal anatomy varies widely between patients, challenging surgeons operating in the sinuses. Ethmoid sinus anatomy is so variable it has been referred to as a labyrinth. Accordingly, reliable, consistent anatomic landmarks aid surgeons operating in this region. The goal of this investigation was to explore our observations and hypothesis that the ethmoidal bulla and the uncinate process are not entirely separate structures but rather attach, and the attachment could potentially provide a landmark for surgeons performing ethmoid and frontal recess surgery. Ethmoid sinus anatomy was studied in 57 sinonasal complexes through a variety of methods including gross anatomic dissection, endoscopic dissection and 3D CT stereoscopic imaging. The uncinate process and ethmoidal bulla were noted to fuse at the superior aspect of the hiatus semilunaris in 57/57 cases, forming a genu-like feature in the anterior ethmoid. This consistent anatomic feature related closely to the frontal sinus drainage pathway, which drained medial to it in 44/57 (77%) cases. The anterior ethmoidal "genu" appears to be an excellent anatomic feature that surgeons can use during ethmoid and frontal recess surgery. High resolution 3D stereoscopic CT scan is capable of demonstrating sinonasal anatomy in a detailed fashion previously only achieved by cadaveric dissection. This technology can potentially allow for a virtual dissection of a patient's anatomy prior to surgery and could improve minimally invasive procedures and reduce complications. Clin. Anat. 32:534-540, 2019. © 2019 Wiley Periodicals, Inc.

Maxillary sinus angiomyolipoma: A case report and overview.

Otolaryngologists are called upon to evaluate and treat sinonasal masses discovered incidentally on imaging studies. Although common conditions such as sinonasal polyps and mucus retention cysts predominate, it is prudent practice to formulate a differential diagnosis to identify unusual conditions. We present a case of a maxillary sinus mass in a 78-year-old man that was discovered incidentally on brain imaging and subsequently identified on biopsy as an angiomyolipoma (AML). AMLs are benign hamartomatous tumors that rarely occur in extrarenal locations. Only a few cases have been reported in the nasal cavity. We believe our case represents the first reported instance of AML arising within a maxillary sinus. Identification of intratumoral fat within the mass on imaging studies may suggest the diagnosis of AML preoperatively. Close interdisciplinary collaboration among the otorhinolaryngology, radiology, and pathology services is beneficial for patient management. We report this case to raise awareness that AML can arise in this previously unreported location. Moreover, we wish to emphasize that AML should be considered in the differential diagnosis when imaging studies demonstrate a well-defined, heterogeneous, fat-containing solitary mass in the nasal cavity or maxillary sinus.

Fibroblasts isolated from human middle turbinate mucosa cause neural progenitor cells to differentiate into glial lineage cells.

Transplantation of olfactory ensheathing cells (OECs) is a potential therapy for repair of spinal cord injury (SCI). Autologous transplantation of OECs has been reported in clinical trials. However, it is still controversial whether purified OECs or olfactory mucosa containing OECs, fibroblasts and other cells should be used for transplantation. OECs and fibroblasts were isolated from olfactory mucosa of the middle turbinate from seven patients. The percentage of OECs with p75(NTR+) and GFAP(+) ranged from 9.2% to 73.2%. Fibroblasts were purified and co-cultured with normal human neural progenitors (NHNPs). Based on immunocytochemical labeling, NHNPs were induced into glial lineage cells when they were co-cultured with the mucosal fibroblasts. These results demonstrate that OECs can be isolated from the mucosa of the middle turbinate bone as well as from the dorsal nasal septum and superior turbinates, which are the typical sites for harvesting OECs. Transplantation of olfactory mucosa containing fibroblasts into the central nervous system (CNS) needs to be further investigated before translation to clinical application.

The frontal intersinus septum takedown procedure: revisiting a technique for surgically refractory unilateral frontal sinus disease.

OBJECTIVES/HYPOTHESIS: Unilateral frontal sinus obstruction presents a surgical challenge when outflow tract osteoneogenesis or dense scarring is present. Frontal sinus obliteration is often employed as a last resort, but this procedure has potential long-term complications. In some cases, endoscopic modified Lothrop or unilateral drillout procedures may be effective options; however, restenosis rates are often high. Here we report our experience using frontal intersinus septum takedown (FISST) to address unilateral obstruction while preserving the opposite frontal outflow tract. STUDY DESIGN: A retrospective review was performed of 12 patients with unilateral frontal sinus opacification due to irreversible frontal recess obstruction who underwent FISST. Surgical outcomes were assessed based on symptoms and computed tomography (CT) resolution of frontal sinus disease. RESULTS: All 12 patients undergoing FISST had significant improvement in their symptoms. Ten postoperative CT scans were available for review, all showing continued patency of the interfrontal connection, and nine out of 10 with resolution of radiographic frontal sinus disease. Eleven of the procedures were performed via trephination, and one was achieved endoscopically. CONCLUSIONS: In patients with one obstructed frontal sinus and a functional contralateral sinus, removal of the intersinus septum allows for adequate sinus drainage and significant clinical improvement. The success of FISST may be surprising given knowledge of mucociliary clearance patterns, but may be effective because of the naturally dependent position of the frontal sinus ostium.

Piezoelectric surgical device in endoscopic sinus surgery: an initial clinical experience.

Revision endoscopic sinus surgery presents special challenges, such as the need to remove thick osteoneogenic bone close to the orbit or skull base. Currently available drills and microdebriders have shortcomings for this task, including risk to the underlying periorbita or dura. Recently, piezoelectric ultrasound technology has been used to remove bone while preserving adjacent soft tissue structures. This technology has been effective in several areas of the body, and it logically follows that it may have beneficial rhinologic applications. The purpose of this medical communication is to report an initial clinical experience with piezoelectric technology in revision sinus surgery. The piezoelectric surgical device was used during revision endoscopic sinus surgery in 14 patients in the author's practice from June 2006 to January 2009. All patients had an underlying bone component to their sinus condition, such as osteoneogenesis adjacent to the orbit or skull base. The piezoelectric surgical device performed successfully in removing osteoneogenic bone, and no complications were noted from its use. Piezoelectric surgical technology generates low-frequency ultrasound that dissects bone and appears to offer an option to mechanical drill instrumentation when used during endoscopic sinus surgery to address thick osteoneogenic bone. The clinical experience reported herein shows initial feasibility of the technology in selected cases of sinus surgery. On the basis of the favorable observations from this clinical experience, further exploration and discussion would appear to be valuable.

Physiologic alterations in the murine model after nasal fungal antigenic exposure.

OBJECTIVE: To determine whether a recently developed murine model of fungus-induced sinonasal inflammation demonstrated alterations in ciliary activity and expression of inflammatory cytokines. STUDY DESIGN: A prospective randomized controlled study of rhinosinusitis after fungal antigenic sensitization was performed with intraperitoneal aspergillus antigen injection followed by intranasal antigen challenge for 4 weeks. Saline solution was used in a parallel fashion for control animals. SUBJECTS AND METHODS: Six mice were used to validate the model. Additional 15 mice were used for ciliary beat frequency (CBF) analysis and cytokine expression with multiplex technology. Mean values for degree of inflammation, secretory hyperplasia, CBF, and cytokine expression were compared. RESULTS: Histologic analyses demonstrated dense chronic inflammation in aspergillus-challenged animals versus sparse inflammatory cells in controls. Significant differences in mean of aspergillus-challenged versus control animals were observed in degree of inflammation (P < 0.01), secretory hyperplasia (P < 0.01), CBF (P < 0.00002), IL-1alpha (P < 0.0002), IL-1beta (P < 0.0003), IL-4 (P < 0.02), TNF-alpha (P < 0.02), and RANTES (P < 0.01). CONCLUSION: Alteration in baseline CBF accompanied by increased expression of specific inflammatory cytokines was observed in aspergillus-challenged mice.

Spontaneous CSF leaks: a paradigm for definitive repair and management of intracranial hypertension.

OBJECTIVE: To report our outcomes with the repair of spontaneous cerebrospinal fluid (CSF) leaks and to demonstrate how management of underlying intracranial hypertension improves outcomes. STUDY DESIGN: Retrospective review of spontaneous CSF leaks treated at the University of Pennsylvania Health System from 1996 to 2006. Data collected included demographics, nature of presentation, body mass index (BMI), site of skull base defect, surgical approach, intracranial pressure, and clinical follow-up. RESULTS: Fifty-six patients underwent repair of spontaneous CSF leaks. Eighty-two percent (46 of 56) were obese (average BMI 36.2 kg/m(2)). Nine patients had multiple CSF leaks. Fifty-four patients (96%) had associated encephaloceles. Fifty-three CSF leaks (95%) were successfully repaired at first attempt (34 months of follow-up). Intracranial pressures averaged 27 cm H(2)O. Patients were treated with acetazolamide or, in severe cases, with a ventriculoperitoneal shunt. CONCLUSIONS: Spontaneous CSF leaks have the highest recurrence rate of any etiology. With treatment of underlying intracranial hypertension coupled with endoscopic repair, the success rate (95%) approaches that of other etiologies of CSF leaks.

Clinical outcomes of endoscopic and endoscopic-assisted resection of inverted papillomas: a 15-year experience.

BACKGROUND: The endoscopic resection of sinonasal inverted papillomas (IPs) has been well described. However, the majority of published reports in the literature are small case series with limited clinical follow-up. The aim of this retrospective study was to review the experience with the endoscopic and endoscopic-assisted resection of IPs at a major academic tertiary care facility and assess long-term outcomes. METHODS: A retrospective review of endoscopic and endoscopic-assisted resections of IP was performed. Charts were reviewed for standard demographic data, operative technique, adjuvant approaches, complications, and postoperative follow-up times. RESULTS: One hundred fourteen patients (average age, 56 years) underwent endoscopic or endoscopic-assisted resection for IPs with a mean disease-free follow-up of 40 months (7-135 months). Seventeen patients developed disease after endoscopic or endoscopic-assisted resection for a recurrence rate of 15%. Average time to recurrence was 23 months. Combined approaches were used when indicated in 34% (39/114) of patients, including adjuvant osteoplastic flap, midface degloving, trephine, or Caldwell-Luc approaches. Four patients (4%) had cerebrospinal fluid leaks that were successfully repaired endoscopically. CONCLUSION: In this large series of endoscopically resected IPs with extensive clinical follow-up, recurrences occurred an average of 23 months after the procedure. This emphasizes the importance of long-term endoscopic follow-up to detect recurrences in all patients. Endoscopic or endoscopic-assisted resection of IPs is a valid technique in this series with recurrence rates comparable with open approaches.

Radiographic signs of elevated intracranial pressure in idiopathic cerebrospinal fluid leaks: a possible presentation of idiopathic intracranial hypertension.

BACKGROUND: Traditionally, idiopathic cerebrospinal fluid (CSF) leaks have been associated with normal intracranial pressure (ICP). We speculate that at least one subset of these leaks may be associated with elevated ICP, more specifically, idiopathic intracranial hypertension (IIH). We sought to identify radiographic manifestations suggestive of elevated ICP in 14 patients with idiopathic CSF leaks who clinically and epidemiologically resembled patients with IIH. METHODS: We retrospectively reviewed high-resolution CT, MRI, and/or CT cisternography in 14 patients with elevated ICP and idiopathic CSF leaks for radiographic manifestations suggesting increased ICP. RESULTS: Arachnoid pits were seen in 79% of patients, empty sella was seen in 50% of patients, meningo(encephalo)celes were seen in 50% of patients, and dural ectasia was seen in 35% of patients, respectively. Optic nerve findings were not shown as commonly seen as described in the literature. CONCLUSION: We show a subset of patients with idiopathic CSF leaks who display radiographic signs consistent with increased ICP who may represent an alternative presentation of IIH.

Safety and outcomes of balloon catheter sinusotomy: a multicenter 24-week analysis in 115 patients.

OBJECTIVE: The aim of this study was to further evaluate the safety and effectiveness of balloon catheter devices to dilate obstructed sinus ostia/perform sinusotomy. METHODS: Through a prospective, multicenter evaluation, safety was assessed by rate of adverse events, patency was determined by endoscopic examination, and sinus symptoms were determined by the Sino-Nasal Outcome Test (SNOT 20). RESULTS: At the conclusion of the 24-week analysis, endoscopy determined that the sinusotomy was patent in 80.5% (247 of 307) sinuses and nonpatent in 1.6% (5 of 307), and could not determine ostial patency status in 17.9% (55 of 307). Of the ostia visualized on endoscopy, 98% were patent (247 of 252), while 2% (5 of 252) were considered nonpatent. SNOT 20 scores showed consistent symptomatic improvement over baseline. Revision treatment was required in 3 sinuses (3 of 307 sinuses, 0.98%) in 3 patients (3 of 109 patients, 2.75%). CONCLUSION: Balloon catheter technology appears safe and effective in relieving ostial obstruction. Patients were pleased and indicated that they experienced symptomatic improvement.

Gene expression analysis in sinonasal polyposis before and after oral corticosteroids: a preliminary investigation.

OBJECTIVE: To characterize gene expression in sinonasal polyps and to gain insight into change in expression after oral corticosteroid treatment. STUDY DESIGN AND METHODS: Nasal polyps were obtained before and after oral corticosteroid treatment and gene expression was analyzed with a focused gene array technique. RESULTS: Pretreated sinonasal polyps demonstrated high gene expression for chemokine and leukotriene receptor genes (CCR2, CCR5, CX3CL1, and LTB4R) in all patients. After treatment, the global effects of corticosteroids were evident on gene expression. CONCLUSIONS: Gene array techniques hold promise as a research method in sinonasal polyposis. The potential benefits, as well as the potential challenges, in using these research methods will be discussed.

Spontaneous cerebrospinal fluid leaks: a variant of benign intracranial hypertension.

OBJECTIVES: Previous reports indicate that elevated intracranial pressure (ICP) may cause spontaneous cerebrospinal fluid (CSF) leaks. In this study we examined the clinical diagnosis of benign intracranial hypertension (BIH) in this population using the modified Dandy criteria. METHODS: We performed a retrospective review of clinical data and measurements of ICPs after surgical repair. RESULTS: Sixteen patients with spontaneous CSF leaks were surgically treated from 1996 to 2002. In 11 patients with CSF pressure measurements, strict adherence to the modified Dandy criteria definitively confirmed a diagnosis of BIH in 8 patients (72%) and a likely diagnosis in the 3 remaining patients. The mean ICP was 31.1 cm H20 (range, 17.3 to 52 cm H2O), and 81% of the patients were obese middle-aged women. Clinically, all patients had signs and/or symptoms of elevated ICP, such as headache (91%), pulsatile tinnitus (45%), hypertension (45%), balance problems (27%), and visual complaints (18%). Surgical repair was 100% successful in leak cessation over a mean follow-up of 14.1 months. CONCLUSIONS: Most patients with spontaneous CSF leaks fulfill the modified Dandy criteria; thus, this disorder appears to be a variant of BIH. Further investigation is needed to determine the exact cause of elevated CSF pressures in this group and whether medical or surgical treatments to correct the intracranial hypertension are warranted.

Catheter-based dilation of the sinus ostia: initial safety and feasibility analysis in a cadaver model.

BACKGROUND: Over the past 20 years, many patients have benefited from endoscopic sinus surgery and its ability to relieve sinus obstruction. However, problems still occur with surgery, thereby leaving room for innovation. Recently, catheter-based technology has provided new options for treating cardiac, vascular, and urologic diseases. We speculated that catheter technology also might offer new treatment options for sinusitis patients. The purpose of this investigation was to explore the feasibility and safety of catheter-based technology to relieve sinus ostial obstruction. METHODS: Anatomic models and human cadaver specimens were used initially to design and iterate catheters to open sinus ostial drainage pathways. Thereafter, the safety of balloon-catheter dilation was evaluated in six human cadaver heads. CT scan obtained before and after catheter ostial dilation was analyzed for evidence of catheter-induced trauma. Dilated ostia also were examined by endoscopy and gross anatomic dissection for unwanted catheter-induced trauma. RESULTS: Catheters successfully dilated 31 of 31 ostia, including 9 maxillary, 11 sphenoid, and 11 frontal ostia/recesses. CT scan, endoscopy, and gross anatomic dissection revealed that such dilation did not cause trauma to surrounding structures such as the orbit or skull base. Mucosal trauma imparted by catheter dilation appeared to be less than that normally seen with standard endoscopic instruments. CONCLUSION: This initial study suggests that catheter technology can be used to dilate sinus ostia safely. Mucosal preservation and ease of use make catheters an attractive minimally invasive treatment strategy. Additional testing in patients is indicated to gain additional safety information and to explore the usefulness of catheter-based technology.

Endoscopic management of cerebrospinal fluid rhinorrhea.

Cerebrospinal fluid rhinorrhea and meningoencephaloceles extending into the nasal cavity from the anterior, middle, and posterior cranial fossae often are managed by otolaryngologists. A thorough understanding of the underlying pathophysiology, management principles, and treatment options is essential to achieve optimal outcomes. Surgical and medical management is highly individualized and depends on many factors, including etiology, anatomic site, and underlying intracranial pressure. This article highlights the history, physiology, pathophysiology, diagnosis, surgical techniques, and postoperative care relevant to nasal cerebrospinal fluid leaks and encephaloceles.