Objectives: Ideal mucosal incision followed by adequate osteotomy is the key to successful endonasal endoscopic dacryocystorhinostomy. Hence anatomical correlation of intranasal lateral nasal wall landmarks to lacrimal sac and duct was done with secondary computed tomography (CT) correlation. Methods: A descriptive study of 10 adult cadaver head sections fixed with 10% formaldehyde solution was done in the anatomy and radiology departments of a tertiary hospital from 2010 to 2011. Following CT scan, these were sagittally sectioned to 10 right and left specimens. Measurement of anatomical landmarks in CT and dissection were taken by metric ruler and digital calipers respectively. With application of paired t test, mean was calculated. Results: Maxillary line was clearly identified in 75% of cadavers, the majority overlapping the lacrimal sac. In all cadavers superior end of lacrimal sac was above the axilla, distance between them being 8.88 mm. Length of lacrimal sac was 11.72 mm. These showed positive correlation with CT scan. Distance between anterior edge of lacrimal sac and axilla was 10.58 mm. Genu was at or posterior to nasolacrimal duct in the majority, the length of duct being 10.27 mm. This showed positive correlation with CT. Conclusions: Important endonasal landmarks are of middle turbinate—axilla and genu (bony), and maxillary line (mucosal). Mucosal Incision, 9 to 10 mm above axilla, anterior to maxillary line and genu, 10 to 11mm long to just above level of genu, is sufficient to expose lacrimal sac up to its inferior limit. Preoperative CT scan can be reserved for revision or post-traumatic nasolacrimal sac pathology.

<p class="abstract"><strong>Background:</strong> The aim of this study was to assess the accuracy of preoperative contrast enhanced computed tomography (CECT) of neck with or without magnetic resonance imaging (MRI) in determining cartilage erosion in patients with laryngeal and hypo pharyngeal cancers and correlate this with the final histopathology report (HPE).</p><p class="abstract"><strong>Methods:</strong> Forty patients diagnosed clinically with stage 3 laryngeal and hypo pharyngeal cancer were subjected to flexible laryngoscopy and CECT of neck. Patients with doubtful cartilage erosion on CECT were subjected to additional MRI. Radiologic findings including cartilage sclerosis, invasion and penetration on CECT and MRI were then correlated with HPE in patients who underwent total laryngectomy.  </p><p class="abstract"><strong>Results:</strong> CECT scan showed cartilage invasion in 30 cases. There were ten patients with doubtful cartilage erosion on the CECT scan who were then subjected to additional limited MRI which was compared with CECT scan and operative findings. Thyroid cartilage erosion was confirmed on MRI in five of the ten cases where CECT scan findings were equivocal. CECT scan failed to predict cricoid and arytenoid cartilage invasion in five cases and six cases respectively. Though MRI was a problem-solving tool, it had one false positive result.</p><p class="abstract"><strong>Conclusions:</strong> CECT scan helped to identify cartilage erosion in 91.3% of cases which immensely contributed to the staging and treatment planning of laryngeal and hypo pharyngeal cancers. When findings on CECT are equivocal, the addition of MRI improves the accuracy of detecting cartilage involvement.</p>

<p class="abstract"><strong>Background:</strong> The aim of this study is to assess the thyroid gland involvement in the preoperative contrast enhanced computed tomography (CECT) of neck with histopathology (HPE) in determining the indications for ipsilateral thyroidectomy in patients undergoing total laryngectomy in laryngeal and hypopharyngeal cancers.</p><p class="abstract"><strong>Methods:</strong> Forty patients diagnosed clinically with stage 3 laryngeal and hypopharyngeal cancer were subjected to CECT of neck. Patients with cartilage erosion and extra laryngeal spread on CECT (T3, T4a) were routinely taken for total laryngectomy, partial pharyngectomy and hemi thyroidectomy. Specimens were sent for histopathological analysis and which was compared with preoperative CECT scan.  </p><p class="abstract"><strong>Results:</strong> Of the forty cases, only four patients had thyroid gland involvement in CECT scan and 2 of the 40 had thyroid gland involvement in histopathology. Of the four patients where the CT scan which showed infiltration of the thyroid gland, none had thyroid gland involvement in histopathology. In two patients where thyroid gland was involved in histopathology, CT scan failed to pick up the thyroid gland involvement. Those two patients with histologically proven thyroid gland involvement identify as transglottic malignancy with cartilage erosion and extra laryngeal spread.</p><p class="abstract"><strong>Conclusions:</strong> Our study concludes that an ipsilateral hemi-thyroidectomy is probably still indicated in transglottic cancer with cartilage invasion and/or extra laryngeal spread.</p>