A Study on Morphometry and Related Surgical Importance of Naso Lacrimal Duct

Introduction: The Nasolacrimal duct is the terminal part of the nasolacrimal apparatus or tear apparatus. The anatomy of lateral nasal wall is Important for planning the surgeries on lacrimal duct through intranasal approach. Objective: The current study was designed to review the anatomy of nasolacrimal duct in relation to the lateral nasal wall. Material and method: Thirty sagittal sections (14 right and 16 left side) of head and neck of formalin fixed adult cadavers of known sex, gender, ethnicity present in department of anatomy GMCH, Chandigarh were studied. The following parameters were made using a digital calliper and rounded off to the nearest millimetres. 1.Length of nasolacrimal duct (NLD Length) 2. Nearest distance from the nasolacrimal duct to maxillary sinus ostium (NLD - MSO) 3. Nearest distance from the NLD to the anterior nasal spine. (NLD- ANS)4. Nearest distance of the intranasal orifice of the NLD to the nasal floor (NLD- NF) 5. Nearest distance of the intranasal orifice of the NLD to the nasal roof. (NSD- NR) 6. Nearest distance of the intranasal orifice of the NLD to the anterior attachment of the Inferior concha. (NSD- AIT). Observations: In our study the average length of the NLD was 19.8±1.57mm. The intranasal orifice of the NLD was observed to be located on an average of 24.5±2.6mm from the anterior nasal spine, ranging from 5.5-2. 9mm.The average distance from the nasal roof was found to be 32.2±1.67mm and 16.08±1.71mm from nasal floor. In addition, the average distance from the anterior attachment of inferior nasal concha was found to be 14.82±2.37mm. In our study the NLD was an average of 4.08±0.67mm anterior to MSO at the level of the anterior attachment of the MT. On Comparing right and left side The NLD Was found to be slightly longer 22.7 in comparison of 22.2 mm on left side. The distance of NLD From MSO was also found to be larger on left side. The distances of NLD-ANS, NLD NR, NLD -AIT and NLD- NF were also longer on left side. Conclusion: We found that most of the parameters were closer to a study done by Ertugel while the NLD-NF distance was more in our specimen. Running title: nasolacrimal duct: morphometry, surgical importance

Anatomy of the maxillary sinus ostium: a cadaveric study

Background: Recognition of the maxillary sinus position is tedious as it is small and not easily seen. A detailedknowledge of the anatomical variations of maxillary sinus opening is required for endoscopic surgeons toperform safe surgeries. The aim of the present study is to determine the anatomical location of the maxillaryostium in a cadaveric specimen. The position of the accessory maxillary sinus, if present is also noted to furtherbenefit the surgeons.Materials and Methods: Thirty bisected halves of the formalin fixed adult head and neck specimens were obtainedfrom the Department of Anatomy. The anterior part of the skull was divided in the midline and then the nasalseptum was removed taking care not to damage the osteomeatal components. Probes were used in identifyingthe location of maxillary sinus ostium. Various other parameters like vertical diameter, transverse diameter,distance between ostium and anatomical landmarks such as inferior concha and hard palate were measured.Results: In accordance to the parameters considered in the current study, the following results were observed.The maxillary sinus ostium was present in the posterior 1/3rd of the Hiatus semilunaris in 53% of the cadavers.The most common shape of maxillary sinus ostium was oval. The mean vertical and transverse diameters ofostium were 2mm and 2.6mm respectively. The perpendicular distance of the ostium from the lower border ofinferior concha was 14.6 mm and from the upper border of the hard palate was 17.5 mm.Conclusion: The knowledge about the variations in location of the maxillary sinus Ostium and the distances ofthe ostium from the major anatomical landmarks will help the maxillofacial surgeons and otolaryngeologists toperform the surgical procedures safely.

Anatomy of accessory maxillary sinus ostium with clinical application.

Background: The “osteomeatal complex” of the middle meatus is a group of anatomical structures that includes; principle maxillary sinus ostium and accessory maxillary sinus ostium. Its beauty lies in its complexity. This osteomeatal complex contributes to the final common drainage pathway of maxillary, anterior ethmoidal and frontal sinuses. Principle maxillary sinus ostium (PMO) is universally present in all population while if extra opening is present in addition to principle maxillary sinus ostium then this is called accessory maxillary sinus ostium. The principle maxillary sinus ostium is opened in the Hiatus semilunaris and it is located on the highest part of medial wall of maxillary sinus as compared to accessory maxillary sinus ostium. Accessory maxillary sinus ostium located in the anterior nasal fontanelle (ANF), posterior nasal fontanelle (PNF), and hiatus semilunaris. Aims & Objective: The endoscopic sinus surgeons must have a detailed knowledge of inconsistent situation of principle maxillary sinus ostium (PMO) and accessory maxillary sinus ostium as there are important structures like orbit superiorly and nasolacrimal duct medially lying adjacent to medial wall of maxillary sinus where above said openings are situated. Materials and Methods: This study was carried out in the department of Anatomy of government medical college, Surat and Surat municipal institute of medical education and research (SMIMER) where 54 cadaveric heads were cut in midsagital section into 108 half heads and then incidence, location and side of accessory maxillary ostium was studied. Results: Among 108 half heads, accessory maxillary ostium was found in 20 (18.5%) half heads. Out of these 20 half heads, in 12 (60%) half heads accessory maxillary sinus ostium is present on right side while in remaining 8 (40%) half heads, it is on the left side. Similarly out of these 20 half heads, 16 (80%) half heads shows unilateral accessory maxillary sinus ostium either on right side or on left side while 4 (20%) half heads shows bilateral accessory maxillary sinus ostium. Out of these 20 half heads, 7 (35%) half heads shows double AMO (which includes 4 (20%) in ANF on the left side, 2(10%) in PNF on the right side and 1 (5%) in HS on the right side) while 13 (65%) were single in number (which includes 9 (45%) in ANF on both left and right side, 4 (20%) in PNF). All double accessory maxillary sinus ostia situated in the ANF and HS were placed in horizontal plane whereas accessory maxillary ostium which was situated in the PNF was placed vertically. Accessory maxillary sinus ostium was varies in size and shape. These accessory maxillary sinus ostia were 0.5 to 5 millimeters in size and round or oval in shape. Similarly out of these 20 (18.5%) half heads in which Accessory maxillary sinus ostia were present 70% Accessory maxillary sinus ostia were found in the anterior nasal fontanelle (ANF), 25% in posterior nasal fontanelle (PNF), and 5% in hiatus semilunaris (HS). Most of the accessory maxillary sinus ostia (65%) were single in number at the various places while double accessory maxillary sinus ostia were also found 20% in the ANF, 10% in the PNF 5% in the HS. Conclusion: Clinically the presence of accessory maxillary sinus ostium is extremely beneficial for surgical intervention of the functional endoscopic sinus surgery which is designed to remove the blockage of maxillary sinus ostium and to restore normal sinus ventilation and mucociliary function.

Surgical Anatomy around the Maxillary Sinus Ostium in Cadavers

OBJECTIVES: The goal of this study is to observe the anatomy around the maxillary sinus ostium and gain an understanding that will help prevent serious complications during middle meatal antrostomies. MATERIALS AND METHODS: Dissection of the maxillary sinuses was carried out in 64 embalmed frozen cadavers, 105 maxillary sinuses. Using a digital ruler, forceps and a malleable probe, we measured the important anatomical relationships around the maxillary sinus ostium and uncinate process, the accessory ostium, and the nasolacrimal duct. RESULTS: 1) The mean width of the uncinate process was 4.9 mm in the mid portion ; 2) A natural ostium of the canal type was observed in 76% of cases ; 3) An accessory ostium was found in 18% of cases and the mean size was 3.17x2.41 mm ; and 4) The mean shortest distance between the nasolacrimal duct and the natural ostium was 4.8 mm. CONCLUSION: Surgeons must keep surgical anatomy in mind to prevent complications when performing endoscopic sinus surgery.