Relationship between sphenoid sinus volume and protrusion of internal carotid artery and optic nerve: a 3D segmentation study on maxillofacial CT-scans

Anatomical variation in the sphenoidal sinuses in patients with chronic rhinosinusitis: A CT scan study

Computerized tomography (CT) of the skull base region has become an indispensable tool for endoscopic sinonasal surgery.

Objectives

Fundamental knowledge of the sinus anatomy is crucial for preoperative surgical planning. The aim of this research was to evaluate associations between the anatomical variations sphenoidal sinuses and chronic rhinosinusitis (CRS) by using CT.

Methods

A descriptive study was performed on patients with CRS, who were referred to the department of radiodiagnosis and imaging for CT scanning. Parameters were compared between the study and control groups.

Results

Among the anatomical variations, the presence of bilateral accessory septa within the sphenoidal sinus, and dehiscence and protrusion of the internal carotid artery and optic nerve (ON), were high in men and women in the case group compared with the control group. Among the anatomical variations in the sinonasal region of the male participants, a significant association (p < 0.05) was observed with ON protrusion and ON dehiscence. ON protrusion (OR = 2.168) in men was associated with elevated risk of CRS in the study population.

Conclusion

Knowledge of the anatomical variations in the sphenoid sinuses enables better understanding of the limits of surgical dissection during the treatment of sphenoid sinus surgeries.

Sphenoid Sinus Pneumatization Types and Correlation with Adjacent Neurovascular Structures Using Cone-Beam Computed Tomography

Aims: This study aimed to assess the sphenoid sinus pneumatization types and their correlation with adjacent neurovascular structures using cone-beam computed tomography (CBCT). Materials and methods: This cross-sectional study was conducted on 97 CBCT scans of patients over 18 years of age that were retrieved from the archives of the Oral & Maxillofacial Radiology Department of School of Dentistry. Type of sphenoid sinus pneumatization based on its relationship with sella turcica (conchal, presellar, sellar, and postsellar), the correlation of internal carotid artery (ICA) and optic nerve (ON) with the sinus cavity in the axial and coronal planes (smooth or prolonged type), and presence of Onodi cells and their correlation with the sphenoid sinus (lateral, superior, and superolateral) were all evaluated on CBCT sections. Data were analyzed by the Chi-square and Fisher's exact tests (alpha = 0.05). Results: Postsellar type was the most common sphenoid sinus pneumatization type (82.5%). The Smooth type was the most common form of correlation of ON and ICA with the sphenoid sinus. Onodi cells were noted in 28.9% of the cases; among which, the lateral type had the highest prevalence. Conclusion: Considering the high prevalence of sphenoid sinus pneumatization, Onodi cells, and ON and ICA protrusion in our study population, CBCT should be requested prior to trans-sphenoidal surgical procedures to prevent perioperative and postoperative complications.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-03796-0.

Artificial Intelligence in Lung Cancer Screening: The Future Is Now

Lung cancer has one of the worst morbidity and fatality rates of any malignant tumour. Most lung cancers are discovered in the middle and late stages of the disease, when treatment choices are limited, and patients' survival rate is low. The aim of lung cancer screening is the identification of lung malignancies in the early stage of the disease, when more options for effective treatments are available, to improve the patients' outcomes. The desire to improve the efficacy and efficiency of clinical care continues to drive multiple innovations into practice for better patient management, and in this context, artificial intelligence (AI) plays a key role. AI may have a role in each process of the lung cancer screening workflow. First, in the acquisition of low-dose computed tomography for screening programs, AI-based reconstruction allows a further dose reduction, while still maintaining an optimal image quality. AI can help the personalization of screening programs through risk stratification based on the collection and analysis of a huge amount of imaging and clinical data. A computer-aided detection (CAD) system provides automatic detection of potential lung nodules with high sensitivity, working as a concurrent or second reader and reducing the time needed for image interpretation. Once a nodule has been detected, it should be characterized as benign or malignant. Two AI-based approaches are available to perform this task: the first one is represented by automatic segmentation with a consequent assessment of the lesion size, volume, and densitometric features; the second consists of segmentation first, followed by radiomic features extraction to characterize the whole abnormalities providing the so-called "virtual biopsy". This narrative review aims to provide an overview of all possible AI applications in lung cancer screening.

Application of expanding bilateral sphenoid sinus plasty in the treatment of sphenoid sinus diseases

Expanding bilateral sphenoid sinus plasty is an essential technique for the treatment of sphenoid sinus diseases, such as refractory sphenoid sinusitis, sphenoid sinus cyst, fungal sphenoid sinusitis, sphenoid sinus carcinoma and sphenoid sinus chordoma. The present study evaluated the potential application of expanding bilateral sphenoid sinus plasty in the treatment of sphenoid sinus diseases. A retrospective medical record review of 42 patients treated with the expanding bilateral sphenoid sinus plasty from December 2012 to December 2018 was performed in a tertiary-care university hospital. A follow-up of the surgical effects and complications was performed. Of the 42 patients, the symptoms were relieved after operation in all except preoperative hyposmia in 2 and impaired vision in one with no obvious improvement. No complications such as nasal bleeding, olfactory hypofunction and perforation of nasal septum occurred. Follow-up data revealed good mucosal epithelization in all patients within a mean time of 8.6 weeks. Endoscopic sinus reexamination demonstrated that the sphenoid sinus orifice was well opened, and no cases of sphenoid sinus orifice closure were observed. Expanding bilateral sphenoid sinus plasty, with advantages of clearly exposed surgical field, full opening of the sinus cavity, high surgical safety, short epithelialization time and intuitionistic postoperative follow-up, demonstrated great promise for greater use in the treatment of sphenoid sinus diseases in the future.

Assessment of Anatomical Uniqueness of Maxillary Sinuses through 3D-3D Superimposition: An Additional Help to Personal Identification

Paranasal sinuses represent one of the most individualizing structures of the human body and some of them have been already analyzed for possible applications to personal identification, such as the frontal and sphenoid sinuses. This study explores the application of 3D-3D superimposition to maxillary sinuses in personal identification. One hundred head CT-scans of adult subjects (equally divided among males and females) were extracted from a hospital database. Maxillary sinuses were segmented twice from each subject through ITK-SNAP software and the correspondent 3D models were automatically superimposed to obtain 100 matches (when they belonged to the same person) and 100 mismatches (when they were extracted from different individuals), both from the right and left side. Average RMS (root mean square) point-to-point distance was then calculated for all the superimpositions; differences according to sex, side, and group (matches and mismatches) were assessed through three-way ANOVA test (p < 0.017). On average, RMS values were lower in matches (0.26 ± 0.19 mm in males, 0.24 ± 0.18 mm in females) than in mismatches (2.44 ± 0.87 mm in males, 2.20 ± 0.73 mm in females) with a significant difference (p < 0.001). No significant differences were found according to sex or side (p > 0.017). The study verified the potential of maxillary sinuses as reliable anatomical structures for personal identification in the forensic context.

Anatomical configurations of the optic canal in the sphenoid sinus in a Hispanic population: computed tomography based study

OBJECTIVE

The prevalence of the optic canal anatomical variants across the sphenoid sinus varies widely among different ethnic groups. This study aimed to analyse the anatomical variants of the optic canal and their relationship to sphenoid sinus pneumatisation in a Hispanic population.

METHOD

A review of 320 sphenoid sinuses by high-resolution computed tomography was performed. DeLano's classification of the optic canal, presence of dehiscence, septa insertion, sphenoid sinus pneumatisation and presence of Onodi cells were established.

RESULTS

Dehiscence of the optic canal was observed in 4.7 per cent (n = 15) of the analysed sinuses. Type 4 and 3 optic canals were significantly more frequent among postsellar sphenoid sinuses than other patterns of sphenoid sinus pneumatisation (p = 0.002 and p = 0.018). A type 4 optic canal has a higher tendency to present inserted septum than other optic canal types (p = 0.014).

CONCLUSION

This study described the optic canal variants in a Hispanic population, which complements existing literature addressing other ethnicities.

Development of the sphenoid sinus from newborn to age 18: A computed tomography imaging analysis

OBJECTIVES

The sphenoid sinus (SS) is an important anatomical formation in terms of its location and relationship with important neurovascular structures. It is essential to evaluate the pneumatization and dimensions of the SS with Computed Tomography (CT) in the preoperative period of transsphenoidal interventions to be performed on tumors located in this region. The aim of this study was to evaluate the correlation of the volume and dimensions of the SS measured with CT with age in the period from birth to 18 years of age.

METHODS

In this retrospective study, a total of 360 brain, paranasal sinus, temporal bone and maxillofacial CT scans of individuals from birth to 18 years of age were evaluated. The cohort was divided into 18 groups with 20 (10 female, 10 male) patients in each age group. The height, width, length and volume values of the SS were measured on CT and their correlations with age and the differences between genders were evaluated statistically.

RESULTS

It has been determined that the increases in the size and volume of the SS accelerate especially between 1 and 2 years of age and begins to reach adult dimensions after 12 years of age. Height and length of the sphenoid sinus showed a high correlation coefficient (r = 0.717 and r = 0.731 respectively) with age, while its width and volume showed a moderate correlation coefficient (r = 0.662 and 0.543 respectively). There was no statistically significant difference between the genders in terms of SS height, width, length and volume.

CONCLUSIONS

SS dimensions and volume showed a logaritmic growth pattern from birth to 18 years. The results of this study may help to better understand the normal development of SS in children and may serve as a reference for more comprehensive CT studies. In addition, it can help surgeons to evaluate the developmental characteristics of SS in surgical interventions for SS in children.

Artificial Intelligence in Lung Cancer Imaging: Unfolding the Future

Lung cancer is one of the malignancies with higher morbidity and mortality. Imaging plays an essential role in each phase of lung cancer management, from detection to assessment of response to treatment. The development of imaging-based artificial intelligence (AI) models has the potential to play a key role in early detection and customized treatment planning. Computer-aided detection of lung nodules in screening programs has revolutionized the early detection of the disease. Moreover, the possibility to use AI approaches to identify patients at risk of developing lung cancer during their life can help a more targeted screening program. The combination of imaging features and clinical and laboratory data through AI models is giving promising results in the prediction of patients’ outcomes, response to specific therapies, and risk for toxic reaction development. In this review, we provide an overview of the main imaging AI-based tools in lung cancer imaging, including automated lesion detection, characterization, segmentation, prediction of outcome, and treatment response to provide radiologists and clinicians with the foundation for these applications in a clinical scenario.

Relationships of sphenoid sinus pneumatization with internal carotid artery characteristics

Objective

We explored the clinical significances of the relationships among sphenoid sinus aeration, intersphenoid sinus septum (ISS), and internal carotid artery (ICA).

Methods

We retrospectively reviewed the preoperative paranasal sinus computed tomography scans and the medical charts of 490 patients who were treated by the endoscopic endonasal transsphenoidal approach. We analyzed sphenoid sinus pneumatization, number of ISS, and positional relationships between the ICA and ISS (including ICA prominence and the thickness of surrounding bone).

Results

ISS were often present in the ICAs of patients with presellar pneumatization (36.2%; p = 0.042). Sphenoid sinus pneumatization status significantly differed according to number of ISS (p < 0.001), ICA prominence (p < 0.001), ISS insertion into the ICA (p = 0.042), and distance from ISS to ICA (p = 0.004). When sphenoid sinus aeration was poor, the ICA was not prominent, and the ISS were attached to or lay close to the paraclival ICA.

Conclusions

Patients with presellar pneumatization exhibited less prominent ICAs, and more ISS attached to or near the paraclival ICA, than did other patients. Therefore, particular caution is required when using the endoscopic endonasal transsphenoidal approach to treat patients with poor sphenoid sinus aeration.

Human identification performed with skull's sphenoid sinus based on deep learning

Human identification plays a significant role in the investigations of disasters and criminal cases. Human identification could be achieved quickly and efficiently via 3D sphenoid sinus models by customized convolutional neural networks. In this retrospective study, a deep learning neural network was proposed to achieve human identification of 1475 noncontrast thin-slice CT scans. A total of 732 patients were retrieved and studied (82% for model training and 18% for testing). By establishing an individual recognition framework, the anonymous sphenoid sinus model was matched and cross-tested, and the performance of the framework also was evaluated on the test set using the recognition rate, ROC curve and identification speed. Finally, manual matching was performed based on the framework results in the test set. Out of a total of 732 subjects (mean age 46.45 years ± 14.92 (SD); 349 women), 600 subjects were trained, and 132 subjects were tested. The present automatic human identification has achieved Rank 1 and Rank 5 accuracy values of 93.94% and 99.24%, respectively, in the test set. In addition, all the identifications were completed within 55 s, which manifested the inference speed of the test set. We used the comparison results of the MVSS-Net to exclude sphenoid sinus models with low similarity and carried out traditional visual comparisons of the CT anatomical aspects of the sphenoid sinus of 132 individuals with an accuracy of 100%. The customized deep learning framework achieves reliable and fast human identification based on a 3D sphenoid sinus and can assist forensic radiologists in human identification accuracy.

Correlation Between Anatomic Variations of Sphenoid Sinuses and Pituitary Adenoma

BACKGROUND

Many persons have studied relationship between anatomic variations (AVs) of sphenoid sinuses (SS) and paranasal disease, but no research has been done to reveal the correlation between AVs of SS and sellar region lesions.

OBJECTIVE

To compare AVs of SS between sellar region lesions and healthy persons and analyze factors affecting the volume of SS and explore the correlation between AVs of SS and pituitary adenomas (PAs).

METHODS

Clinical data of 53 PAs as experiment group and 30 healthy persons as control team was reviewed. Computed tomography images of SS performed at Tianjin Huanhu Hospital were studied. The AVs of SS including degree of pneumatization, type of intersinus septum (IS), and volume of SS were evaluated by ITK-SNAP software.

RESULTS

Age, gender, degree of pneumatization, and type of IS had no significant difference between groups, while the volume of SS in experiment group was smaller than that in control group (P < 0.05). The volume of SS was associated with age, sex, degree of pneumatization, type of IS in control group, and degree of pneumatization, type of IS in experiment group. In experiment group, patients with postoperative pathological examination ki67 ≥ 3% had bigger volume and higher recurrent rate (P < 0.05).

CONCLUSION

Visualizing different orientations and 3D model of SS is conducive to the success of trans-sphenoid surgery. Pituitary adenomas can deform the SS leading to smaller volume. The volume of SS can be a factor used to predict the outcome of PAs.

Ruptured infectious ICA pseudoaneurysm into the sphenoid sinus after maxillofacial infection, successfully treated by selective embolization

Background

Intracranial infectious aneurysms are cerebral aneurysms caused by pathogen-induced inflammation undermining the arterial wall. We present a rare case of inflammatory pseudoaneurysm of cavernous internal carotid artery (ICA).

Case Description

A 51-year-old female with a recent diagnosis of acute lymphoblastic leukemia developed maxillofacial infection with Pseudomonas and Acinetobacter after chemotherapy onset. Initial plain computed tomography (CT) revealed bony dehiscence of the left ICA canal, as well as bilateral protrusion of the vessel within the sphenoid sinus. Following infection spread into the left sphenoid sinus, she presented with episodes of intermittent epistaxis, without any profound vascular abnormalities on postcontrast CT. CT angiography that was performed 15 days later, due to refractory epistaxis, illustrated a large narrow necked irregular shape pseudoaneurysm of the left paraophthalmic ICA, extending into the ipsilateral sphenoid sinus. The aneurysm was completely occluded by selective embolization without parent or adjacent vessel sacrifice, documented on both intraoperative and follow-up angiogram, with no recurrence of epistaxis.

Conclusion

Conclusively, ruptured internal carotid infectious aneurysms are rare but potentially fatal causes of epistaxis when extended into the sphenoid sinus. Selective coiling is feasible and can provide definitive treatment of these lesions.

Segmentation procedures for the assessment of paranasal sinuses volumes

BACKGROUND

The paranasal sinuses are complex anatomical structures, characterised by highly variable shape, morphology and size. With the introduction of multidetector scanners and the development of many post-processing possibilities, computed tomography became the gold standard technique to image the paranasal sinuses. Segmentation allows the extraction of metrical and shape data of these anatomical components that can be applied for diagnostic, education, surgical planning and simulation, and to plan minimally invasive interventions in otorhinolaryngology and neurosurgery.

DISCUSSION

Our aim was to provide a review of the existing literature on segmentation, its types and application, and the data obtained from this procedure. The literature search was conducted on PubMed (including Medline), ScienceDirect and Google Scholar databases, using the keywords as follows: 'paranasal sinuses', 'frontal sinus', 'maxillary sinus', 'sphenoid sinus', 'ethmoid sinus', in all possible combinations with the keywords 'segmentation' and 'volumetric analysis'. Inclusion criteria were: articles written in English, on living human subjects, on the adult population and focused on paranasal sinuses analysis.

CONCLUSION

This article provides an overview of the types and main application of segmentation procedures on paranasal sinuses, and the results provided by the studies on this topic.

Prevalence of accessory septations of sphenoid sinus in pediatric population: Applications to endoscopic sinus surgery

Sphenoid sinus accessory septations and their possible insertion on internal carotid artery (ICA) may represent a risk for endoscopic sinus surgical procedures. However, scarce data on this variant for children are available so far. This retrospective study included 220 maxillofacial CT-scans equally divided among males (13.4 ± 2.1 years) and females (13.9 ± 2.2 years). On each CT-scan, prevalence of accessory septations, number of septations in sphenoid sinuses, and their possible insertion onto ICA bone walls were recorded. Significant differences in protrusion and insertion of septations onto the ICA bone walls according to sex were assessed through Chi-square test (p < .05). Possible correlations between the prevalence of accessory septations, ICA insertion, and number of accessory septations and age were assessed by means of Pearson's regression (p < .05). On average, 66% of males and 71% of females had at least one accessory septation, without significant differences according to sex or age (p > .05): septal insertion on ICA was found in 13% of subjects, without any significant difference for sex or age (p > .05). The number of septations was significantly increased with age (p < .05). The present study showed that the prevalence of accessory septations and insertion onto the ICA are independent of age and these results are similar to those reported in adults. Results will be useful for the management of endoscopic sinus surgery.

Intraoperative Sphenoid Sinus Volume Measurement as an Alternative Technique to Intraoperative Computer Tomography

Isolated sphenoid sinus disease (ISSD) is where there is a group of pathologies characterized by inflammation in one or both sphenoid sinuses. Although computer tomography (CT)-based 3D reconstruction remains the gold standard among noninvasive approaches to ISSD diagnostics, no standardized techniques for direct intraoperative measurements of the sphenoid sinus volume in ISSD patients have been documented. We suggest a novel technique for the intraoperative measurement of the sphenoid sinus volume. Our technique is based on filling the sinus with 0.01% methylene blue solution after an endoscopic endonasal sphenoidotomy. The proposed technique was applied to 40 ISSD patients during surgery. Obtained intraoperative measurements were compared to noninvasive measurements from 3D reconstructions based on preoperative CT scans. Our results demonstrated that the obtained measurements did not exhibit significant differences exceeding 0.4 cm³, with CT-scan-based measurements in 39 out of 40 cases (p < 10⁻⁶, Wilcoxon sign-rank nonparametric test), thus confirming the accuracy of the proposed technique. Disagreements between direct intraoperative and CT-based measurements in a single case have been attributed to the presence of remaining pathological masses in the sinus, which was further confirmed during the secondary check of the operated sinus. Accordingly, we suggest that the agreement between the CT-based and intraoperative volume measurements can be used as an indicator of the successful elimination of all pathological masses from the sinus without having to perform an adequate exposure of the entire sphenoid sinus to reduce intraoperative bleeding. The proposed technique is accurate and does not require the involvement of specialized intraoperative CT scanners and avoids additional radiation exposure for the patient during an additional postoperation CT scan to confirm the success of the surgery.

Sphenoid sinuses: pneumatisation and anatomical variants-what the radiologist needs to know and report to avoid intraoperative complications

PURPOSE

Sphenoid sinuses are pneumatised structures, placed in the body of the sphenoid bone, with highly variable morphology. The strict relationships with vascular and nervous structures determine the importance of their anatomical variants in otorhinolaryngology and neurosurgery; a precise understanding of the complex anatomy and anatomic variations of these structures is pivotal for radiological diagnosis of paranasal sinuses pathology and for surgical planning, to avoid potential complications. Our aim is to describe the anatomical variants of sphenoid sinuses, and to help general radiologists and specialists in endoscopic surgery in becoming familiar with these sensitive anatomical structures.

METHODS

A literature search of PubMed and Embase (Elsevier) databases was performed using the keywords "sphenoid sinus" and "anatomy, "sphenoid sinus" and "anatomic variants", "sphenoid sinus", and "anatomic variations".

RESULTS

We described the anatomical variants of the sphenoid sinuses anatomy, according to their size, shape, degree of pneumatisation, protrusion of anatomical structures into their lumen, superimposition of ethmoid cells (Onodi cells), and presence of accessory septations CONCLUSION: The information provided by this study may help in the identification and description of the anatomical variations of the sphenoid sinuses and their relationship to neurovascular structures.

Postoperative complications after bimaxillary orthognathic surgery: A retrospective study with focus on postoperative ventilation strategies and posterior airway space (PAS)

PURPOSE

The aim of this study was to evaluate the impact of extubation time on postoperative complications in patients undergoing bimaxillary orthognathic surgery. We therefore retrospectively compared the effect of early extubating (EE) in the operating room versus delayed extubating (LE) on the intensive care unit (ICU) regarding postoperative complications and length of ICU/hospital stay (LOICUS/LOHS). Furthermore, we analyzed the influence of the PAS change on postoperative complications.

METHODS

The clinical data of 117 patients were retrospective analyzed regarding postoperative complications using Clavian-Dindo Classification. Volumetric calculations of the pre- and postoperative PAS were conducted using ITK-SNAP software. The Fisher's exact test was performed to evaluate the significance of differences between categorical variables. Continuous variables were analyzed using the Mann-Whitney U-Test or the Kruskal-Wallis one-way analysis of variance. Regression analysis was used estimating predictors for postoperative complications.

RESULTS

EE led to significant shortening of LOICUS (p < 0.001) and LOHS (p = 0.023). In total, we recorded 38 complications (minor n = 30; major n = 8) within the hospital stay. Complication rates were without significant differences with respect to the postoperative ventilation strategy. Large changes in PAS volume led to an increase in the major complication rates (p = 0.031). Increase or decrease of PAS was independent from postoperative complication rates (p = 1.000). Higher body mass index (p = 0.04) and a higher ASA PS score (p = 0.016) were associated with increased major complication rates.

CONCLUSION

Early extubation after surgery is a safe procedure and is associated with a reduced LOICUS and LOHS. Complications seem to occur more frequently in marked changes of the PAS and should be considered in perioperative risk stratification.

Relationship between sphenoid sinus volume and accessory septations: A 3D assessment of risky anatomical variants for endoscopic surgery

Sphenoid sinus accessory septations involve serious complications during their removal for the injury of the internal carotid artery (ICA) and the optic nerve (ON). The relationships of this anatomical variant with sphenoid size still remain unclear. In the present study, 260 patients (equally divided among sexes, aged between 18 and 92 years) were retrospectively assessed. Number of accessory septations and their relationship with ICA and ON were recorded. The 3D model of sphenoid sinuses was extracted. Pearson's coefficient was calculated to assess correlations between the volume of sphenoid sinuses and the number of septations (P < 0.05). Sex-related differences in prevalence of septations inserted onto ICA or ON were assessed through chi-square test (P < 0.05). Differences in volume between patients with and without ICA or ON septal insertions were assessed through Mann-Whitney test (P < 0.05). In most of the cases, two septations were found (24.6%), whereas only 21.9% of patients did not show any septum. ICA and ON septal insertions were found in 20.8% and 7.7% of cases, respectively. Number of septations significantly increased with sinus volume, independently from sex (P < 0.001). Moreover, volume was significantly higher in patients with ICA septal insertion (P < 0.001), whereas no difference was found between subjects with and without ON septal insertion (P > 0.05). The present study first proved that septations and probability of ICA insertion are related with sphenoid volume. On the other side, ON insertion does not depend upon sphenoid sinuses size. Anat Rec, 303:1300-1304, 2020. © 2019 American Association for Anatomy.