Pallanch, John F.

AbstractObjectiveDescribe a reliable anatomical landmark that can be used to locate the maxillary sinus natural ostium (MSNO) during endoscopic surgery, even if the uncinate process is preserved.DesignDescriptive anatomical.SettingAn anatomical and radiological study was performed to evaluate the consistency of the landmark, denominated "M" line.Subjects and MethodsDissections were performed in 57 cadaver heads (114 sides). In addition, 73 computerised tomography (CT) scans (146 sides) of patients with chronic inflammatory sinonasal disease were analysed using a three‐dimensional (3D) reconstruction computer program.ResultsThe "M" line crossed the MSNO in 112 dissected sides (98.2%) and 140 sides at CT 3D reconstruction (95.9%).ConclusionThe "M" line is a reliable anatomical landmark for predicting MSNO location. As such, it could improve and facilitate endoscopic sinus surgery, using traditional, minimally invasive or uncinate preserving techniques.

ObjectiveTo determine whether using image guidance technology with 3‐dimensional image segmentation increases the endoscopic surgeon's accuracy, efficiency, and confidence in identifying the anterior ethmoidal artery.MethodsThis is a cross‐sectional study of attending physicians and residents at an academic medical center. Because identification of the anterior ethmoidal artery during image‐guided surgery can be challenging, we studied the effect of anterior ethmoidal artery image segmentation (ie, partitioning and coloring) on surgeon test performance. A computerized test was administered to 16 surgeons who were asked to identify the anterior ethmoidal artery on multiplanar computed tomographic images and to answer multiple‐choice questions. Half the questions showed segmented images of the anterior ethmoidal artery, and half showed images without segmentation. Efficiency and accuracy of identification and subjective surgeon confidence were determined for each question. Descriptive statistics were used to compare test performance for identification of the anterior ethmoidal artery on images with or without segmentation.ResultsPercentage of correct answers (P <. 001), efficiency (P <. 001), and confidence (P <. 001) in identification of the anterior ethmoidal artery were significantly better with segmented computed tomographic images.DiscussionWe demonstrated that use of segmented images improves surgeons’ accuracy, confidence, and efficiency for identification of the anterior ethmoidal artery.Implications for PracticeWe describe how segmentation can allow surgeons to improve the surgical course by increasing their accuracy, confidence, and efficiency in identifying the anterior ethmoidal artery.

In this retrospective study we used active, anterior mask rhinomanometric methods to measure nasal resistance before and after surgery for nasal obstruction. The study group comprised 60 patients with nasal obstruction who had 63 preoperative and postoperative rhinomanograms and the control group contained 14 asymptomatic patients who underwent rhinomanometric studies before transnasal, transsphenoidal pituitary surgery. Before surgery the study group had significantly higher total and combined unilateral nasal resistances than either the control group before surgery (p < 0.05 and p < 0.01, respectively) or the study group after surgery (p < 0.0001 for both comparisons). Surgery normalized the nasal resistances of the study group in relation to the control group. A total nasal resistance greater than 1 cm H2O/L/sec or a unilateral resistance greater than 3.5 cm H2O/L/sec suggests clinically significant nasal obstruction. Airway narrowing and obstructive symptoms correlated with airway resistance in the preoperative patient, but symptoms did not correlate well with postoperative resistance.

Eighty normal adults without nasal symptoms were studied to determine normal nasal resistance values and the variation of nasal resistance in normal adults. A microprocessor‐based system for collection and analysis of transnasal pressure and flow was used to obtain nasal resistance values. Unilateral and total transnasal pressure and flow values were determined before and after decongestion of the nose with 1% phenylephrine spray. The distribution of the 80 resistance values was found to be skewed to the right. Log transformation of the resistance values was the best method to normalize their distribution. The mean and variation of normal nasal resistance are reported at flows of 0.1 and 0.2 L/sec, at pressures of 0.5 and 1 cm H2O, and at radii of 1, 2, and 3 on the pressure‐flow curve.

ObjectiveTo define relationships between the frontal sinus opening, ostia of other frontal recess cells, and endoscopic landmarks and to develop a clinically useful framework to guide frontal sinus surgery.Study DesignRetrospective review.SettingTertiary care academic referral center.MethodsAdult patients with computed tomography (CT) without sinonasal pathology were included. Virtual endoscopy (using OsiriX) and corresponding CT reconstructions were used to identify all visible ostia in the frontal recess and characterize their positions in spaces between the uncinate/agger nasi (U), bulla ethmoidalis (EB), and middle turbinate (MT).ResultsTwo hundred sides in 100 patients (median age 51 years, 62% female) were analyzed. The “center” of each map was defined as the intersection of spaces between U, EB, and MT. The frontal sinus opening was in the “center” in 53% of frontal recesses, lateral to this position in 29%, and anterior in 11%. When the frontal sinus opening was at the “center,” anterior ostia drained frontal Kuhn T cells in 51% and intersinus septal cells in 23%. The skull base attachment of the apical strut of the uncinate process demarcated medial and lateral within the space between U and EB, with the opening to the frontal sinus medial in 68% and lateral in 31%. Left‐right asymmetry in frontal sinus openings was noted in 46% of patients.ConclusionCombining preoperative imaging and knowledge of these anatomic relationships may facilitate more efficient frontal outflow tract identification and instrumentation. This represents the first and largest description of ostial configurations relative to endoscopic structural landmarks.Level of Evidence:4

Background Since 1972, patients with large nasal perforations, who were symptomatic, and who were not candidates for surgery, had the option of custom prosthetic closure at Mayo Clinic. Although septal prostheses have helped many patients, 27% of pre-1982 patients chose not to keep the prosthesis in place. Two-dimensional computed tomography (CT) sizing resulted in more of the patients choosing to retain the prosthesis. The introduction of three-dimensional (3-D) printing to the sizing process offered the potential of further improved retention by refinement in prosthesis fit. Objective To describe the fabrication of nasal septal prostheses by using 3-D printing for sizing and to compare the retention rate of 3-D-sized prostheses with those that used previous sizing methods. Methods Twenty-one consecutive patients who had placement of septal prostheses sized by using 3-D printed templates were studied. CT image data were used to print 3-D templates of the exact shape of the patient's septal perforation, and medical-grade silastic prostheses were fabricated to fit. In four cases, the 3-D printed template allowed preoperative surgical simulation. Metrics collected included prosthesis retention; symptoms, including intranasal crusting and epistaxis; and previous prosthetic closure failures. Results Twenty of the twenty-one patients had improvement in symptoms. The mean diameter of the perforations was 2.4 cm; the mean closure time by the end of the study period was 2.2 years. All but two patients chose to keep their prosthesis in place, for a retention rate of 90%. Seven patients with successful closure had failed previously with prior prosthesis sized without the current 3-D printing methodology. This 90% retention rate exceeded the previous rates before the introduction of 3-D sizing. Conclusion Sizing done by 3-D printing for prosthetic closure of nasal septal perforations resulted in a higher retention rate in helping patients with these most-challenging nasal septal perforations.

One hundred seventy‐one patients had closure of symptomatic nasal septal perforations by insertion of a Silastic nasal septal prosthesis between June 1972 and August 1981. Follow‐up revealed that successful closure of the defect was accomplished in 73% of cases, with reduction in crusting and epistaxis and improvement in nasal respiration in many cases. Prefabricated prostheses have been effective in treating smaller perforations. The treatment of four patients with unusually large septal perforations by custom‐carved prostheses sized using computerized axial tomographic scanning is described.

Background Nasal congestion and/or obstruction represents a prevalent and extensively studied problem. No published research exists that describes the impact of nasal hair (vibrissae) on nasal obstruction. Objective To assess the impact of nasal vibrissae on subjective and objective measurements of nasal obstruction. Methods In this prospective study, 30 healthy participants without nasal symptoms were assessed for baseline vibrissae density and were treated with a topical decongestant. The subjects were then asked to subjectively assess nasal breathing by using four questions from the Nasal Obstruction Symptom Evaluation instrument before undergoing rhinomanometry. Nasal vibrissae were then trimmed, and the participants repeated the subjective and objective assessments. Pre- and postintervention outcomes, including symptom scores, nasal airflow, and resistance, were compared by using statistical analysis. Results Statistically significant improvement was noted in subjects’ nasal airway specific symptom scores and in objective measurements of their nasal airway. Patients with moderate or many vibrissae at baseline were noted to have greater likelihood of improvement in subjective and objective obstruction assessments than patients rated with few. Conclusion In these 30 subjects, statistically significant improvement occurred in both subjective and objective assessments of nasal obstruction, particularly in patients with greater density of vibrissae. These findings support further study of the potential benefit of the reduction of vibrissae density in some patients with nasal obstruction.

BackgroundCommonly used computed tomography (CT) staging systems for chronic rhinosinusitis (CRS) focus on the sinuses and do not quantify disease in the olfactory cleft. The goal of the current study was to determine whether precise measurements of olfactory cleft opacification better correlate with olfaction in patients with CRS.MethodsOlfaction was assessed using the 40‐item Smell Identification Test (SIT‐40) before and after sinus surgery in adult patients. Olfactory cleft opacification was quantified precisely using three‐dimensional (3D), computerized volumetric analysis, as well as via semiquantitative Likert scale estimations at predetermined anatomic sites. Sinus opacification was also quantified using the Lund‐Mackay staging system.ResultsThe overall cohort (n = 199) included 89 (44.7%) patients with CRS with nasal polyposis (CRSwNP) and 110 (55.3%) with CRS without nasal polyposis (CRSsNP). The olfactory cleft opacified volume correlated with objective olfaction as determined by the SIT‐40 (Spearman's rank correlation coefficient [Rs] = −0.461; p < 0.001). The correlation was significantly stronger in the CRSwNP subgroup (Rs = −0.573; p < 0.001), whereas no appreciable correlation was found in the CRSsNP group (Rs = −0.141; p = 0.141). Correlations between sinus‐specific Lund‐Mackay CT scoring and SIT‐40 scores were weaker in the CRSwNP (Rs = −0.377; p < 0.001) subgroup but stronger in the CRSsNP (Rs = −0.225; p = 0.018) group when compared to olfactory cleft correlations. Greater intraclass correlations (ICCs) were found between quantitative volumetric measures of olfactory cleft opacification (ICC = 0.844; p < 0.001) as compared with semiquantitative Likert grading (ICC = 0.627; p < 0.001).ConclusionQuantitative measures of olfactory cleft opacification correlate with objective olfaction, with the strongest correlations seen in patients with nasal polyps.

ObjectivesA truly objective method of measuring disease severity in chronic rhinosinusitis (CRS) has only recently existed. We evaluated computed tomography (CT) scans of CRS patients using this novel objective 3D computerized system and compared results with a novel 2D computerized analysis of a single coronal slice through the osteomeatal complex (OMC) and subjective methods including Lund‐Mackay and Zinreich's modified Lund‐Mackay.Study DesignProspective multicenter study.SettingTwo academic tertiary referral centers.Subjects and MethodsForty‐six adults with a diagnosis of CRS underwent CT examination and received an intramuscular triamcinolone injection, dosage weight dependent, followed by CT scan 4 to 5 weeks later. Recruitment lasted 21 months. Scans were evaluated with all 4 scoring methods over 5 months.ResultsThe Lin's concordance class correlation (CCC) of the OMC method revealed the best correlation to the 3D volumetric computerized values (0.915), followed by the Zinreich (0.904) and Lund‐Mackay methods (0.824). Posttreatment results demonstrated that both the OMC (0.824) and Zinreich's (0.778) methods had strong agreement with the 3D volumetric methods and were very sensitive to change, whereas the Lund‐Mackay (0.545) had only moderate agreement.ConclusionComputerized CT analysis provides the most comprehensive, objective, and reproducible method of measuring disease severity and is very sensitive to change induced by treatment intervention. A 2D coronal image through the OMC provides a valid, user‐friendly method of assessing CRS and is representative of CRS severity in all sinuses. Zinreich's subjective method correlated well overall, but the Lund‐Mackay method lagged behind in disease representation and sensitivity to change.