The association of superior attachment of uncinate process with pneumatization of middle turbinate: a computed tomographic analysis

The Upper Attachment of the Uncinate Process and Anterior Ethmoidal Artery

OBJECTIVE

Variations in the upper attachment of the uncinate process (UP) are important because they can affect frontal sinus drainage and change the morphology. Functional endoscopic sinus surgery (FESS) is the primary technique used to treat chronic medically refractory rhinosinusitis. Uncinectomy is the basis of FESS technique to obtain the best possible result from surgery. The anterior ethmoidal artery (AEA) enters the nasal cavity through the orbital medial wall (lamina papyracea) may also be affected by the upper attachment of the UP. The aim of this study was to investigate a possible link between UP variations and the course of the AEA.

MATERIALS AND METHODS

This retrospective, computed tomography (CT)-based, anatomic study was conducted on 200 healthy adults (100 females and 100 males) by screening bilateral paranasal sinus images. The upper attachment of the UP was classified in 6 types (1-6) based on the Liu classification. The AEA was divided into 4 types (A-D) based on location: anterior to the frontal sinus (A), between the frontal sinus and the middle nasal turbinate (B), and anterior to the posterior ethmoidal cells (C and D). All the CT images were evaluated simultaneously by 2 anatomists and 1 radiologist.

RESULTS

Of the total cases (200 right and 200 left side), 48.8% were type 1 UP attachment, 11.0% type 2, 12% type 3, 9% type 4, 18% type 5, and 1.2% type 6. The AEAs were classified as 12.2% type A, 71.8% type B, 15.2% type C, and 0.8% type D.

CONCLUSION

The course of the AEA through the nasal cavity was observed to shift anteriorly from the ethmoidal bulla to the frontal sinus in patients with UP attached to the lamina papyracea and middle turbinate. Remarkably, the AEA always coursed anterior from the middle nasal turbinate line.

Relationship between the Superior Attachment of the Uncinate Process and Pneumatization of the Middle Turbinate—A Radiological Study

Objective: the superior attachment of the uncinate process (SAUP) is highly variable. Lateral types of SAUP are associated with frontal rhinosinusitis. SAUP in the middle turbinate is more common when the middle turbinate is aerated. We aim to refine these findings by studying the relationship between the SAUP type and the different subtypes of pneumatization of the middle turbinate. Methods: 200 CT sinonasal scans were analyzed by an otolaryngologist and a radiologist. All CT scans were analyzed to study the type of the middle turbinate concha bullosa and lamellar cell and the type of SAUP. Results: 379 sides were analyzed. The prevalence of the various types of SAUP were: Type I: 43.80%, Type II: 22.16%, Type III: 16.36%, Type IV: 3.69%, Type V: 9.76%, and Type VI: 4.22%. When studying the pneumatization of the middle turbinate and the SAUP types, we only found a statistically significant association between the lateral attachment of the uncinate process and the presence of a lamellar cell (p = 0.029). Conclusion: lateral types of SAUP are more likely in the presence of a lamellar cell. This finding, therefore, renders checking for lateral SAUP types in the presence of a lamellar cell even more relevant than when studying the pre-surgical CT scan. In those cases, it is advisable to perform a careful and complete uncinectomy.

Anatomic Variations of Ethmoid Roof and Risk of Skull Base Injury in Endoscopic Sinus Surgery: Statistical Correlations

BACKGROUND

Recent developments in endoscopic sinus surgery (ESS) have increased the need to investigate the complex anatomic variations in the ethmoid roof and skull base, to inform the surgeon about the risk of damaging these crucial areas during ESS.

OBJECTIVE

To offer a detailed description of sinus anatomy focusing on the key surgical landmarks in ESS and frontal recess surgery to standardize a systematic approach during the preoperative sinuses imaging evaluation.Methodology: A total of 220 computed tomography (CT) scans were reviewed to obtain six sets of measurements: the depth of the cribriform plate (CP); the length of the lateral lamella of the cribriform plate (LLCP); the angle formed by the LLCP and the continuation of the horizontal plane passing through the CP; the position of the anterior ethmoidal artery (AEA) at the skull base; the extent of frontal sinus pneumatization (FSP); the type of superior attachment of the uncinate process (SAUP).

RESULTS

The length of the LLCP was statistically significantly correlated with the different Keros classification types, the angle formed by the LLCP with the continuation of the horizontal plane passing through the CP, and with the AEA position at the skull base. The depth of the olfactory fossa was correlated with FSP.

CONCLUSIONS

According to the Keros and Gera classifications, the data obtained from these evaluations allow the assessment of anatomic-radiological risk profiles and can help identify those patients who are high risk for ethmoid roof injury.

Endoscopic frontal recess anatomy directed by the drainage pathways using the connecting plates as landmarks

PURPOSE

To investigate the anatomical features of frontal recess (FR) drainage, and the classification of FR cells and frontal sinus (FS).

METHODS

Fifty sides from 30 adult cadaver heads were examined. FR cells and FS along the drainage pathways were dissected under 0° and 70° endoscopic views using unique connecting structures between the uncinate process and the ethmoid bulla as landmarks.

RESULTS

Connecting plates between the uncinate process and the ethmoid bulla were discovered and termed medial suprainfundibular plate (MSIP), which were observed on each cadaver head, and lateral suprainfundibular plate (LSIP) on 92% (46/50) sides. Separated by MSIP, two drainage pathways were identified and named medial pathways of the FR (MPFR) medial to the MSIP and the lateral pathways of the FR (LPFR) in the lateral side. Different drainage pathways of the FS were confirmed, in which drained into the MPFR in 37 and into the LPFR in 13 of the cadaver sides.

CONCLUSIONS

MSIP is the critical landmark for the recognition of MPFR, LPFR, and the classification of FR cells. The FR resection along LPFR and MPFR facilitated excellent exposure of FS.

Is there a relationship between middle concha bullosa and ethmoid roof asymmetry?

INTRODUCTION

The middle turbinate and ethmoid roof are intranasal structures and may have many anatomical variations. These structures, which serve as anatomical markers during functional sinus surgery, are important for preventing complications and performing a proper surgery. Knowledge of anatomical variations will increase surgical success and reduce complications.

OBJECTIVE

We aimed to investigate the presence of asymmetry in the ethmoidal roof and anatomical variation in patients with and without concha bullosa.

METHODS

In this study, the files of patients who underwent paranasal computed tomography between 2012 and 2018 were analyzed retrospectively. The patients were divided into two groups, as patients with and without concha bullosa. Differences between the two groups in terms of age, gender, septum deviation, ethmoid artery dehiscence, ethmoid roof asymmetry were examined.

RESULTS

The 369 patients included in our study were divided into two groups; those with concha bullosa and those without concha bullosa. The mean age of the patients with concha bullosa was 36.1 ± 13.4 (min-max: 12-74) and the mean age of patients without concha bullosa was 37.5 ± 14.3 (min-max: 10-81). The ethmoid roof depths were compared between the two groups and a significant difference was observed (p < 0.001). The ethmoid roof depth was higher in the group with concha bullosa (p < 0.001).

CONCLUSION

The results of our study indicate that the ethmoidal roof tends to be higher in patients with middle concha bullosa.