The Prevalence of Persistent Petrosquamosal Sinus and Other Temporal Bone Anatomical Variations on High-Resolution Temporal Bone Computed Tomography

Influence of pneumatization on morphology of temporal bone-related vasculatures and their morphometric relationship with ear regions: a computed tomography study

Anatomical variations in the location and position of temporal bone-related vasculature are routinely encountered in clinical practice, contributing to clinical syndromes and complexities in ear-related and neurological surgeries. Pneumatization of the temporal bone (TB) is one of several factors that have been hypothesized to influence the variabilities and variations of these vessels. This study aimed to investigate the association between the degree of pneumatization and the morphologies of some TB-related vessels, as well as their morphometrical relationship with ear regions. Observational retrospective chart review of 496 TBs computed tomographic scans were examined. Different degrees of pneumatization were observed, with hyper-pneumatization being the most common and hypo-pneumatization being the least. Various anatomical variants of the sigmoid sinus (SS), jugular bulb (JB), and internal carotid artery (ICA) were observed. Distances of SS and JB to ear regions were observed to have significant differences (p < 0.05) in laterality. These distances increased relative to increased air cells, showing a significant association (p < 0.05). A significant association (p < 0.001) was also observed between the degree of pneumatization and variants of JB and ICA. High JB, JB dehiscence, and ICA dehiscence were significantly associated with increased pneumatization, while flat JB was significantly associated with decreasing pneumatization. However, no significant association (p = 0.070, p = 0.645) was observed between the degree of pneumatization and morphologies of SS. This study concludes that the degree of pneumatization influences only the jugular bulb variants and ICA dehiscence, as well as the distances of SS and JB to ear regions.

"Leave me alone": anatomical structures and variations seen on computed tomography of the temporal bone

The anatomical structure of the temporal bone is quite complex. There are a great number of anatomical variations that are often confused with temporal bone pathologies, especially fractures. It is important that radiologists and surgeons be able to recognize such variations.

Prevalence of High Jugular Bulb across Different Stages of Adulthood in A Chinese Population

Pulsatile tinnitus, ear fullness, vertigo, hearing disorders, and vestibular dysfunction have been found to be related to high jugular bulb. Anatomical variation in this region also affects surgical planning and approaches. Therefore, knowledge on the detailed anatomy of the high jugular bulb is critical for middle ear and lateral skull base surgery. Prevalence of high jugular bulb is uncertain as data are usually derived from temporal bone specimens and patient reports from hospitals. Therefore, a community-based epidemiological study is necessary to understand the significance of high jugular bulb anatomy. Here, we report a cross-sectional study to characterize the prevalence of high jugular bulb and jugular bulb size using a 3.0 T magnetic resonance imaging. Furthermore, we studied the relationship between the prevalence of high jugular bulb and age-related changes. We enrolled 4539 permanent residents (9078 ears) from two communities in the Shanghai region who underwent magnetic resonance imaging between 2007 and 2011. We divided participants into four subgroups according to age: 35-44 (early middle age), 45-54 (middle age), 55-64 (late middle age), and 65-75 (late adulthood) years. We found that the overall prevalence of high jugular bulb was 14.5% in a Chinese population. There was a higher prevalence of high jugular bulb on the right side and especially in women (both p < 0.001). The occurrence of high jugular bulb was higher in the early middle age group and gradually decreased with age, but was still present in the late adulthood group (p = 0.039). These findings provide useful information on the prevalence of high jugular bulb in a Chinese population and the distribution in age groups, suggesting that high jugular bulb should be considered, even in those without ear disorders. This work serves as a foundation for further research on the relationship between jugular bulb changes and disease symptoms.

Evaluation of the Mastoid Emissary Canals with Computerized Tomography in Patients with Chronic Otitis Media

Background  The mastoid emissary veins (MEVs) pass through the mastoid emissary canal-mastoid foramen (MEC-MF) in the mastoid region of the skull. MEVs can give rise to complications during surgical procedures. The purpose of our study was to investigate the morphological and morphometric characteristics of MECs of patients with clinical chronic otitis media (COM) using high-resolution computed tomography (HRCT). Methods  Patients diagnosed with COM and undergoing temporal HRCT were identified by retrospectively scanning our hospital's automation system. Patients undergoing temporal HRCT for reasons other than COM, infection or tinnitus were identified for the control group by scanning the PACS archive. Sixty-two mastoid regions were examined in 38 unilateral and 12 bilateral COM patients, and 100 mastoid regions in the 50 patients in the control group. The presence of an accessory MEC-MF and MEC-MF diameters was evaluated in both groups. Results  Main MEC diameters on the side of the ear with COM were 1.6 mm, and total accessory and main MEC diameters were 1.8 mm, both values being significantly higher than in the control group. Presence of accessory MEC on the side of the ear with COM was determined at 61.8%, significantly higher than in the control group. Conclusion  Preoperative awareness of cranial venous drainage abnormalities is important to reduce surgical complications. Our study shows that MECs may be wider in diameter in patients with COM. MECs in COM patients must be identified before surgery to the mastoid region.

Prevalence of Petrosquamosal Sinus and Its Clinical Significance: Radiologic Study and Meta-analysis

OBJECTIVE

The petrosquamosal sinus (PSS) is clinically important as it represents a potential hemorrhagic hazard during neurosurgical procedures. This double-approach radiologic study and meta-analysis aimed to assess the imaging characteristics of the PSS on computed tomography (CT) and systematically analyze its prevalence to improve imaging accuracy and assist in neurosurgical management.

METHODS

The retrospective radiologic study included CT scans of 388 patients aged 18 years or older. All patients with any visible intracranial pathologies or history of head trauma were excluded. To identify articles eligible for inclusion in our meta-analysis, an extensive search was conducted through PubMed, Embase, ScienceDirect, Web of Science, and CNKI. Data extracted included investigative method, prevalence of the PSS among subjects, ethnicity, gender, side, laterality, and mean diameter. The extracted data were pooled into a meta-analysis with a random-effects model.

RESULTS

The radiologic study showed that the PSS was visualized in 25.5% of the sides examined, that it was slightly more common among females (27.5%) than males (23.8%) and on the left (21.7%) than the right (29.4%). Its mean diameter was 1.14 ± 0.58 mm. The meta-analysis revealed that the overall prevalence of the PSS in the population is 11.1%, that it is more common in females (27.4%) than males (17.6%), and that a unilateral PSS is more common (78.2%) than a bilateral one (21.8%).

CONCLUSIONS

As a PSS is present in about one tenth of the population, it is important to consider the possibility that it is present when undertaking neurosurgical procedures and to assess preoperative CT scans to avoid complications.