Indications of cone beam CT in head and neck imaging in children

Quantitative assessment of cleft volume and evaluation of cleft's impact on adjacent anatomical structures using CBCT imaging

OBJECTIVES

To determine pre-operative cleft volume and evaluate cleft´s impact on surrounding anatomical structures in children and adolescents with orofacial clefts using cone bean computed tomography (CBCT) imaging.

METHODS

The present retrospective study retrieved CBCT examinations of 68 patients from a previous study. The examinations had been exposed either before (n = 53) or after (n = 15) alveolar bone grafting. Pre-operative volume of cleft was determined, and type and location were evaluated. Morphological changes on the adjacent anatomical structures, including the incisive foramen, the nasal septum and floor, and the inferior turbinate, were assessed.

RESULTS

Mean bilateral cleft volume was 0.76 cm3, while mean unilateral cleft volume was 1.08 cm3; the difference was significant (p < 0.001). Variation in cleft volume, however, was large. The incisive foramen was not visible in the majority of cases with bilateral clefts (71%); the difference was significant (p = 0.001). In cases with unilateral clefts, the nasal septum in 87% was curved towards the cleft or graft side. Also, the mean size of the widest part of the inferior turbinate was 8.8 mm on the cleft or graft side and 10.4 mm on the non-cleft side. The difference was significant (p < 0.001).

CONCLUSIONS

When required, CBCT is a feasible method for quantitatively illustrating alveolar clefts and their impact on the morphological development of surrounding structures. Variation in cleft volume was large.

Indications and use of cone beam computed tomography in children and young individuals in a university-based dental hospital

BACKGROUND

The aim of this study was to evaluate the indications of cone beam computed tomography (CBCT) in children and young individuals in a university-based dental hospital and their association with age, gender and field of view.

METHODS

7131 CBCT scans, taken during 3-year period, were reviewed and a total of 649 pediatric patients (0-18 years) with complete request forms were included. Data related to gender, age, referring department, CBCT indications, field of view (FOV), region of interest (ROI), need for re-exposure and patients received more than one CBCT examination were recorded.

RESULTS

The mean age was 13.57 ± 3.52 years and "malocclusion and dentofacial anomaly" (28.7%) was the most common clinical indication. Facial trauma, dental trauma and supernumerary tooth in males; "malocclusion and dentofacial anomaly" and implant planning in females were recorded more frequently compared to other gender. Maxilla was the most frequently monitored ROI (35.1%) for patients. Small (≤ 10 cm) FOV was preferred in 58.1% of all patients. Large FOV was selected in the majority of patients who underwent CBCT scan for "malocclusion and dentofacial anomaly" (89.6%). The repeated scans constituted 2.3% of patients and 105 patients (16.2%) underwent multiple CBCT scans on different dates for mainly orthodontic follow-up.

CONCLUSIONS

The justification of CBCT scans was not fully compatible with current guidelines and mainly larger FOV was preferred. The number of CBCT examination in children and young individuals tends to increase.

TRIAL REGISTRATION NUMBER

Not applicable.

Evaluation of use of cone beam computed tomography in paediatric patients: A cross-sectional study

BACKGROUND

Cone beam computed tomography (CBCT) is widely used in paediatric dentistry. Appropriate use of CBCT is important because children are more vulnerable to ionizing radiation than adults.

AIM

To investigate the use of CBCT in children by describing reasons for requesting it and its distribution according to age, oral region, and department.

DESIGN

Cone beam computed tomography scans of patients (age < 19 years) who presented to our dental clinic were investigated retrospectively according to sex, age (6-12 [Group 1] and 13-18 [Group 2] years based on dentition), referring department, imaging area (anterior/posterior, mandible/maxilla), and indication. Indications were grouped under five headings according to 2011 SEDENTEXCT guidelines: dental anomalies, impacted teeth, endodontics, bone pathosis, and others.

RESULTS

Overall, 334 CBCT scans at different times and for different reasons in 319 patients were evaluated. In recent years, CBCT requests increased in both age groups. Eighty-five CBCT scans (25.44%) of 78 patients (24.45%) with a mean age of 10.37 ± 1.60 years were examined in Group 1, whereas 249 CBCT scans (%74.55) of 241 patients (75.54%) with a mean age of 15.66 ± 1.70 years were examined in Group 2. The most frequent indication was the assessment of impacted teeth (46.1%). The anterior maxilla was the most frequently monitored region (41.6%). The oral and maxillofacial radiology department was the department that made the most CBCT requests in all the years considered (53.6%).

CONCLUSIONS

The most common indications were the assessment of dentigerous cysts and impacted teeth. There was an increase in the number of referrals to paediatric dentistry.

Comparison of CT and adjusted MRI for evaluating paranasal sinuses surgical key landmarks

Background: Sinus CT is the imaging technique of choice for planning endoscopic sinus surgery (ESS). Although MRI has a better soft tissue demonstration, it is not commonly used for ESS due to suboptimal bone demonstration. We hypothesised that adjustment of certain MRI parameters, would allow better demonstration of bones and enable the surgeon to adequately identify surgical landmarks. Methodology: Twenty patients identified as candidates for ESS underwent CT and adjusted MRI exams of the paranasal sinuses (40 in total). rhinologist and a neuroradiologist independently compared and graded 46 bony structures (23 on each side) in each patient's CT and MRI. Overall, 920 anatomical structures were graded by each observer (1840 structures in total). Statistical analysis included overall and per variable grading distribution for each observer, and overall agreement. Results: MRI images were equal, or superior to CT for assessing paranasal anatomy in 66.8% and 86.4% of structures evaluated by the rhinologist and neuroradiologist, respectively. Overall agreement between observers (77%) was moderate. Conclusion: The rhinologist prefers CT demonstration of bony structures, while the neuroradiologist prefers MRI. Still, with the MRI protocol used in this study, according to both, most bony structures are well demonstrated by MRI.

In vitro measurements of radiation exposure with different modalities (computed tomography, cone beam computed tomography) for imaging the petrous bone with a pediatric anthropomorphic phantom

BACKGROUND

Various imaging modalities, such as multi-detector computed tomography (CT) and cone beam CT are commonly used in infants for the diagnosis of hearing loss and surgical planning of implantation hearing aid devices, with differing results.

OBJECTIVE

We compared three different imaging modalities available in our institution, including a high-class CT scanner, a mid-class CT scanner and an angiography system with a cone beam CT option, for image quality and radiation exposure in a phantom study.

MATERIALS AND METHODS

While scanning an anthropomorphic phantom imitating a 1-year-old child with vendor-provided routine protocols, organ doses, surface doses and effective doses were determined for these three modalities with thermoluminescent dosimeters. The image quality was evaluated using the signal difference to noise ratio (SDNR) and the spatial resolution of a line-pair insert in the phantom head. The dose efficiency, defined as the ratio of SDNR and effective dose, was also compared.

RESULTS

The organ and surface doses were lowest with the high-class CT protocol, but the image quality was the worst. Image quality was best with the cone beam CT protocol, which, however, had the highest radiation exposure in this study, whereas the mid-class CT was in between.

CONCLUSION

Based on our results, high-end CT should be used for surgical planning because it has the lowest dose, while the image quality is still sufficient for this purpose. However, if highest image quality is needed and required, e.g., by ENT surgeons, the other modalities should be considered.

Facial pain: sinus or not?

Facial pain remains a diagnostic and therapeutic challenge for both clinicians and patients. In clinical practice, patients suffering from facial pain generally undergo multiple repeated consultations with different specialists and receive various treatments, including surgery. Many patients, as well as their primary care physicians, mistakenly attribute their pain as being due to rhinosinusitis when this is not the case. It is important to exclude non-sinus-related causes of facial pain before considering sinus surgery to avoid inappropriate treatment. Unfortunately, a significant proportion of patients have persistent facial pain after endoscopic sinus surgery (ESS) due to erroneous considerations on aetiology of facial pain by physicians. It should be taken into account that neurological and sinus diseases may share overlapping symptoms, but they frequently co-exist as comorbidities. The aim of this review was to clarify the diagnostic criteria of facial pain in order to improve discrimination between sinogenic and non-sinogenic facial pain and provide some clinical and diagnostic criteria that may help clinicians in addressing differential diagnosis.