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Computed Tomography Anatomy of the Optic Canal
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Otolaryngology-Head and Neck Surgery, Vol 139, No 2S1, August 2008
Classification System for Results in Eustachian Tube Surgery Carlos Yanez, MD (presenter); Nallely Mora, MD OBJECTIVE: To present a new classification system for reporting results and severity of disease state preoperatively of Eustachian tube (ET) obstructive (ETOD) and non-obstructive dysfunction (ETNOD) based in numerical scores, and to report the results obtained in 40 patients intervened by the author following this criteria. METHODS: A retrospective review of 25 patients was carried out. 20 patients presented obstructive and 5 patients presented non-obstructive (patulous) Eustachian tube dysfunction. These patients were diagnosed and treated between May 2002 and Dec 2007. Patients with ETNOD received laser endoscopic tuboplasty (LEPT) and in patients with ETOD, a cartilage grafting reconstruction of the antero-lateral wall of the ET (ETR) was carried out endonasally. RESULTS: Scores from patients were tabulated accordingly. 18 patients (90%) were symptom free, 1 patient (5%) had partial recurrence of symptoms and 1 patient (5%) had a full recurrence of symptoms at the end of the study in the obstructive dysfunction patients. 3 patients ( 60%) were symptom free, 2 patients (40%) had partial recurrence of symptoms after Eustachian tube reconstruction. Endoscopy, computed tomography, and audiologic results revealed the efficacy or failure of the interventions. CONCLUSIONS: 1) This suggested system could serve as a starting point for Eustachian tube surgeons to develop criteria. It could be adopted if eventually accepted in the field. 2) Results obtained indicate that LEPT is effective in relieving symptoms in selected patients. 3) EPTR for patulous disease may be not effective in some cases. New experiences are further needed. Computed Tomography Anatomy of the Optic Canal Catherine K Hart, MD (presenter); Lee A Zimmer, MD, PhD OBJECTIVE: (1) Analyze the radiographic anatomy of the optic canal in relationship to the sphenoid sinus. (2) Understand the role variation in optic canal anatomy may have in the variability of outcomes in optic nerve decompression. METHODS: Fine cut computed tomography images of the sinuses were obtained with an IRB waiver. Optic canal dimensions were measured on sinus computed tomography images of 96 patients. 191 optic canals were analyzed (111 females, 80 males). Student T-test calculations were performed for statistical analysis on computer software. RESULTS: The average medial canal wall length was 1.48 centimeters (range 0.7-2.3). The length in males was 1.61 centimeters (1.1-2.3) as compared to 1.39 centimeters (0.7-2.0) in females (p⫽8.0-7). The average degree of exposure of the
optic canal exposed to the sphenoid sinus was 101.3 degrees (56-176). The degree of exposure was 105.6 in males versus 98.2 in females (p⫽.01). The potential area of canal exposed to the sphenoid sinus was 0.66 centimeters squared or 28% of the total surface area. The potential area exposed to the sphenoid sinus in males was 0.76cm2 (28%) and 0.58 centimeters squared (27%) in females. CONCLUSIONS: A wide range in medial canal wall length and exposure of the bony optic canal to the sphenoid sinus exists on CT images. The variation in medial canal wall length and in optic canal exposure to the sphenoid sinus may contribute to the variability in success rates of endoscopic optic nerve decompression for optic neuropathy. Does Olfaction Improve After Endoscopic Sinus Surgery? Jamie R. Litvack, MD (presenter); Jess Collin Mace, MPH; Timothy L Smith, MD, MPH OBJECTIVE: No large, prospective, multi-institutional cohort studies have objectively examined the impact of surgery on olfaction with long-term follow-up. The aim of this study was to objectively examine the impact of endoscopic sinus surgery (ESS) on olfactory dysfunction (hyposmia) would benefit from ESS, whereas patients with severe olfactory dysfunction (anosmia) would not. METHODS: In this prospective, multi-institutional cohort study, 111 patients presenting for ESS for treatment of CRS were examined pre-operatively and at 6 and 12 months postoperatively. Demographic, co-morbidity and Smell Identification Test (SIT) data were collected at each time point. Univariate and multivariate analyses were performed. RESULTS: The prevalence of gender-adjusted olfactory dysfunction prior to surgery was 67.5%: 50.4% of patients were hyposmic and 17.1% were anosmic. Surprisingly, hyposmic patients did not significantly improve after surgery (baseline, 6 month, 12 month mean SIT scores: 28.8, 30.0, 29.5). In contrast, patients with anosmia significantly improved after ESS (baseline, 6 month, 12 month mean SIT scores: 9.3, 21.3, 21.7; p⫽0.001); furthermore, improvement was sustained at 12-month follow-up (p⫽0.001). Multivariate linear regression analysis showed that baseline olfactory category and nasal polyposis were significantly associated with improvement in postoperative olfactory function (p⫽0.035, p⫽0.002), whereas age, gender, and disease-severity as measured by CT and endoscopy scores were not. CONCLUSIONS: Contrary to our hypothesis, patients with severe olfactory dysfunction significantly improved after ESS and sustained improvement over time, whereas patients with mild olfactory dysfunction did not.
Otolaryngology-Head and Neck Surgery, Vol 139, No 2S1, August 2008
Classification System for Results in Eustachian Tube Surgery Carlos Yanez, MD (presenter); Nallely Mora, MD OBJECTIVE: To present a new classification system for reporting results and severity of disease state preoperatively of Eustachian tube (ET) obstructive (ETOD) and non-obstructive dysfunction (ETNOD) based in numerical scores, and to report the results obtained in 40 patients intervened by the author following this criteria. METHODS: A retrospective review of 25 patients was carried out. 20 patients presented obstructive and 5 patients presented non-obstructive (patulous) Eustachian tube dysfunction. These patients were diagnosed and treated between May 2002 and Dec 2007. Patients with ETNOD received laser endoscopic tuboplasty (LEPT) and in patients with ETOD, a cartilage grafting reconstruction of the antero-lateral wall of the ET (ETR) was carried out endonasally. RESULTS: Scores from patients were tabulated accordingly. 18 patients (90%) were symptom free, 1 patient (5%) had partial recurrence of symptoms and 1 patient (5%) had a full recurrence of symptoms at the end of the study in the obstructive dysfunction patients. 3 patients ( 60%) were symptom free, 2 patients (40%) had partial recurrence of symptoms after Eustachian tube reconstruction. Endoscopy, computed tomography, and audiologic results revealed the efficacy or failure of the interventions. CONCLUSIONS: 1) This suggested system could serve as a starting point for Eustachian tube surgeons to develop criteria. It could be adopted if eventually accepted in the field. 2) Results obtained indicate that LEPT is effective in relieving symptoms in selected patients. 3) EPTR for patulous disease may be not effective in some cases. New experiences are further needed. Computed Tomography Anatomy of the Optic Canal Catherine K Hart, MD (presenter); Lee A Zimmer, MD, PhD OBJECTIVE: (1) Analyze the radiographic anatomy of the optic canal in relationship to the sphenoid sinus. (2) Understand the role variation in optic canal anatomy may have in the variability of outcomes in optic nerve decompression. METHODS: Fine cut computed tomography images of the sinuses were obtained with an IRB waiver. Optic canal dimensions were measured on sinus computed tomography images of 96 patients. 191 optic canals were analyzed (111 females, 80 males). Student T-test calculations were performed for statistical analysis on computer software. RESULTS: The average medial canal wall length was 1.48 centimeters (range 0.7-2.3). The length in males was 1.61 centimeters (1.1-2.3) as compared to 1.39 centimeters (0.7-2.0) in females (p⫽8.0-7). The average degree of exposure of the
optic canal exposed to the sphenoid sinus was 101.3 degrees (56-176). The degree of exposure was 105.6 in males versus 98.2 in females (p⫽.01). The potential area of canal exposed to the sphenoid sinus was 0.66 centimeters squared or 28% of the total surface area. The potential area exposed to the sphenoid sinus in males was 0.76cm2 (28%) and 0.58 centimeters squared (27%) in females. CONCLUSIONS: A wide range in medial canal wall length and exposure of the bony optic canal to the sphenoid sinus exists on CT images. The variation in medial canal wall length and in optic canal exposure to the sphenoid sinus may contribute to the variability in success rates of endoscopic optic nerve decompression for optic neuropathy. Does Olfaction Improve After Endoscopic Sinus Surgery? Jamie R. Litvack, MD (presenter); Jess Collin Mace, MPH; Timothy L Smith, MD, MPH OBJECTIVE: No large, prospective, multi-institutional cohort studies have objectively examined the impact of surgery on olfaction with long-term follow-up. The aim of this study was to objectively examine the impact of endoscopic sinus surgery (ESS) on olfactory dysfunction (hyposmia) would benefit from ESS, whereas patients with severe olfactory dysfunction (anosmia) would not. METHODS: In this prospective, multi-institutional cohort study, 111 patients presenting for ESS for treatment of CRS were examined pre-operatively and at 6 and 12 months postoperatively. Demographic, co-morbidity and Smell Identification Test (SIT) data were collected at each time point. Univariate and multivariate analyses were performed. RESULTS: The prevalence of gender-adjusted olfactory dysfunction prior to surgery was 67.5%: 50.4% of patients were hyposmic and 17.1% were anosmic. Surprisingly, hyposmic patients did not significantly improve after surgery (baseline, 6 month, 12 month mean SIT scores: 28.8, 30.0, 29.5). In contrast, patients with anosmia significantly improved after ESS (baseline, 6 month, 12 month mean SIT scores: 9.3, 21.3, 21.7; p⫽0.001); furthermore, improvement was sustained at 12-month follow-up (p⫽0.001). Multivariate linear regression analysis showed that baseline olfactory category and nasal polyposis were significantly associated with improvement in postoperative olfactory function (p⫽0.035, p⫽0.002), whereas age, gender, and disease-severity as measured by CT and endoscopy scores were not. CONCLUSIONS: Contrary to our hypothesis, patients with severe olfactory dysfunction significantly improved after ESS and sustained improvement over time, whereas patients with mild olfactory dysfunction did not.