Mark A. Zacharek

Sagittal and coronal dimensions of the ethmoid roof : A radioanatomic study

Background Understanding the anatomy of the ethmoid roof is critical to safe surgical outcomes. Normative data regarding the height and slope of this region have been somewhat limited, derived primarily from cadaveric coronal computed tomography (CT) studies. With triplanar imaging programs, precise multidimensional measurements of the ethmoid roof are now possible. We present a radioanatomic study to characterize normative sagittal and coronal dimensions of the ethmoid roof. Methods Bilateral measurements were taken in 100 consecutive sinus CT scans using ThinClient 3D software. In the sagittal plane, the height of the ethmoid roof was measured in quadrants at five equidistant points between the frontal beak and sphenoid face, referencing the nasal floor. In the coronal plane, the ethmoid roof was measured at three points at the level of the anterior ethmoid artery and at two points at the junction of the posterior ethmoid and sphenoid sinuses. Results When examined sagittally, the right side showed significantly lower skull base heights in the anterior ethmoid compared with the left side (59.0 mm versus 59.8 mm, p = 0.017; 53.7 mm versus 54.5 mm, p = 0.0004). Coronal measurements of the anterior ethmoid roof showed similar significant differences. The anterior ethmoid roof had greater asymmetries of height compared with the posterior ethmoid roof, which was fairly constant. Conclusion This study provides numerical correlates to accepted concepts regarding the shape and slope of the ethmoid roof. Differences in height of the skull base between right and left sides, especially in the anterior ethmoid sinus, may be an important surgical consideration. The posterior ethmoid roof appears to be relatively constant and should serve as a reliable surgical landmark.

Three-dimensional volumetric measurements and analysis of the maxillary sinus.

Background Multiple chronic rhinosinusitis (CRS) staging systems have been developed in an attempt to correlate symptoms with radiological imaging results. Currently, no perfect system exists. We sought to analyze the maxillary sinus (MS) using three-dimensional volumetric measurements and advanced high-resolution CT imaging. Methods We reviewed MS CT scans from 50 control subjects and 50 subjects with documented CRS involving at least one MS. The following measurements were recorded: (1) volume of MS free air, (2) MS mucosal thickening, and (3) MS lateral wall bony thickness. Average Hounsfield unit (HU) values for mucosal thickening among CRS subjects were also recorded. Values are expressed as mean ± SD and median. Values from the CRS patients were compared with healthy controls using Students t-tests. Results Among controls (n = 50), volumes (mL) of right and left MS were 24.1 ± 9.7 and 24.7 ± 9.0, respectively. Among CRS patients (n = 50), the portion of mucosal disease to total sinus volume was 51.8% (right) and 50.7% (left). Mean bony thickness (mm) in controls was 0.98 ± 0.2 (right) and 1.0 ± 0.3 (left). CRS patients had significantly greater bony thickness 1.9 ± 0.8 (right) and 2.0 ± 0.9 (left; p = 0.0001). HU for diseased MS were 30.1 ± 18.7 (right) and 35.7 ± 22.1 (left). Conclusion Three-dimensional volumetric analysis combined with HU calculations and bony thickness measurements represents a new and unique way to evaluate CT scans in patients with CRS. Additional studies correlating symptoms with imaging findings as well as analysis of all paranasal sinuses is the next step toward a novel staging system.

Wound Healing in the Paranasal Sinuses after Coblation, Part II: Evaluation for Endoscopic Sinus Surgery using a Sheep Model:

Background A previous study on wound healing with a rabbit model showed thermal injury to sinus mucosa with complete respiratory re-epithelialization by postoperative day (POD) 29. This study was designed to further understand the pattern of injury using the bipolar radiofrequency plasma process used by the Coblator and evaluate postprocedure healing. Methods Based on experience with our rabbit model, three sheep underwent endoscopic sinus surgery. Coblation was applied to inferior turbinate mucosa in three areas for 2, 4, or 6 seconds. After resection of the contralateral middle turbinate and ethmoidectomy, Coblation was applied to the lateral wall or lamina papyracea for 2 seconds. The ethmoid and turbinate specimens were resected en bloc during necropsy immediately for the first sheep and on POD 14 for the others. Results Coblation resulted in immediate loss of surface respiratory epithelium and thermal-type injury to the underlying seromucinous glands. On POD 14, the Coblation site showed re-epithelialization with respiratory epithelium. The underlying seromucinous glands were replaced by mild fibrosis. A small, well-defined zone of injury was shown. Longer use did not result in a deeper injury. Rather, the depth of injury was dependent on the type of submucosal tissue present. Underlying bone was associated with reactive, regenerative changes. No histological changes were shown in the orbit. Conclusion The effects of Coblation on sheep mucosa show a similar injury and healing pattern to that shown on rabbit mucosa. Based on this work and the previous rabbit study, the Coblator may be an additional tool for use in endoscopic sinus surgery.

Human Papillomavirus Infection and Biomarkers in Sinonasal Inverted Papillomas: Clinical Significance and Molecular Mechanisms

The role of human papillomavirus (HPV) in sinonasal inverted papillomas (IPs) is controversial. Determining the prevalence of HPV infection and its impact on the molecular biology of these tumors is critical to characterizing its role in the pathogenesis of IPs.

Wound healing in the rabbit paranasal sinuses after Coblation: evaluation for use in endoscopic sinus surgery.

Background Bipolar radiofrequency can be used surgically to excise and cauterize tissue simultaneously. It has potential for use in endoscopic sinus surgery (ESS). This study was performed to determine the extent and pattern of injury in the paranasal sinuses with bipolar radiofrequency and evaluate wound healing. Methods Eight rabbits underwent Coblation of maxillary sinus mucosa with biopsy immediately, on postoperative day (POD) 3, 7, 14, or 29. Maxillary mucosa was exposed through the nasal dorsum, and a Coblator PROciseXP wand used on a power setting of 7 for 2 seconds. Three of the rabbits also had Coblation of ethmoid mucosa over the lamina papyracea, after extending the maxillary ostomy, with biopsy immediately. Results Coblation resulted in immediate loss of surface respiratory epithelium and thermal-type injury to the underlying seromucinous glands. On POD 3, the site showed reepithelialization with squamous metaplastic epithelium. The seromucinous glands underwent coagulative necrosis. At POD 7, there was partial replacement of overlying epithelium by respiratory epithelium. The underlying seromucinous glands were lost and replaced by fibroblastic proliferation, with less fibrosis than the mechanically created ostomy site. The underlying bone had reactive, regenerative changes. On PODs 14 and 29, there was further regeneration of respiratory epithelium. Fibrosis was mild. Coblation resulted in gross violation of the bony wall in one maxillary sinus. There were no histological changes in the orbit. Conclusion Rabbit paranasal sinus mucosa heals appropriately after Coblation injury.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

Epidermal growth factor receptor, p16, cyclin D1, and p53 staining patterns for inverted papilloma

The aim of this study was better characterize the staining patterns of inverted papilloma (IP) with and without carcinoma by performing immunohistochemistry for p16, epidermal growth factor receptor (EGFR), p53, and cyclin D1 antibodies in a large patient cohort.

Sinonasal Inverted Papilloma: Prognostic Factors with Emphasis on Resection Margins

Objective We review our institutions experience with the treatment of inverted papilloma (IP) with emphasis on the implications of surgical margins for disease control. Design Retrospective chart review of patients with IP treated at the University of Michigan from 1996 to 2011. Setting Tertiary care center. Participants Patients undergoing surgical resection with curative intent for IP. Main Outcome Measures Overall survival, disease-specific survival, and locoregional control were used as main outcome measures. Results We studied 129 patients including 19 with carcinoma arising from IP. Disease-free rates at 2, 3, and 5 years were 79.7%, 77.9%, and 61%, respectively. Overall, 10 of 18 recurrences were detected > 2 years from follow-up, with recurrences detected up to 8 years from surgery. For benign disease, obtaining tissue margins outside of the primary specimen for margin control did not affect disease control rates. Conclusion IP is a disease that requires significant follow-up periods beyond 2 years. For IP without carcinogenesis, acquiring margins outside of the tumor specimen did not appear to affect disease control rates in this study. No clear predictors of malignancy were seen in this study, which highlights the need for further research to predict this phenomenon.

An approach to the diagnosis and management of acute bacterial rhinosinusitis

The management of patients presenting with nasal congestion, rhinorrhea and facial pressure poses a challenge due to the nonspecific nature of these symptoms. A systematic approach to diagnosing acute bacterial rhinosinusitis is essential prior to offering therapies. This review offers an overview of current definitions, diagnostic algorithms and medical therapies available for the management of acute bacterial rhinosinusitis. Antimicrobial use for acute bacterial rhinosinusitis is substantial and carries a major impact on regional resistance patterns.