The relationship between the uptake of alveolar bone inflammation and of cervical lymph nodes on fluoro-2-deoxy-D-glucose positron emission tomography.

OBJECTIVES: To elucidate the relationships between the maximum standardized uptake value (SUVmax) of alveolar bone and those of lymph nodes (LNs) around the neck on 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography (PET). METHODS: The SUVmax values of alveolar bone and of level IA, level IB, and level IIA LNs of 174 patients, including those with and without active odontogenic inflammation, on PET/CT performed for a health check were retrospectively evaluated. The upper and lower jaws were divided into four blocks (right maxilla, left maxilla, right mandible, and left mandible). The SUVmax values of each block and of the LNs were calculated. The differences in the SUVmax of each LN level between patients with and without odontogenic inflammation, and the relationship between the SUVmax values of alveolar bone and of the LNs were analysed statistically. RESULTS: Significant differences in SUVmax values of bilateral level IB and IIA LNs were found between patients with and without odontogenic inflammation (Mann-Whitney U test: right level IB, P = .008; left level IB, P = .006; right level IIA, P < .001; left level IIA, P = .002), but not in bilateral level IA LNs (Mann-Whitney U test: right level IA, P = .432; left level IA, P = .549). The inflammatory site with the highest SUVmax in level IB LNs was the ipsilateral mandible (multivariate analysis: right, beta = 0.398, P < .001; left, beta = 0.472, P < .001), and the highest SUVmax in level IIA LNs was the ipsilateral maxilla (multivariate analysis: right, beta = 0.223, P = .002; left, beta = 0.391, P < .001). CONCLUSIONS: The SUVmax values of level IB and IIA LNs were associated with a tendency towards a higher SUVmax value of alveolar bone on 18F-FDG-PET.

Correlation between the presence of tonsilloliths and the bone defects by periodontitis on imaging analysis: a pilot study.

BACKGROUND: Very recently, a significant relationship between tonsilloliths and dental plaque-related pathologies was reported using digital panoramic radiographs. Their dynamics over time suggest that tonsilloliths may be in a permanently active phase that functions to remove foreign matter. The aim of the study was to evaluate the relationship between the occurrence of tonsilloliths and the extent of periodontitis. METHODS: A total of 608 patients who underwent both CT and panoramic radiographs were included in the study. Both of two imaging were retrospectively and independently assessed with respect to the presence of tonsilloliths detected on CT and panoramic radiographs, and bone defects caused by periodontitis detected on panoramic radiographs. The type of retrospective study is case-control. Then, the differences between age groups were evaluated with respect to the degree of bone resorption and its correlation with the presence of tonsilloliths. The relationships between categorical variables were assessed using Pearson's correlation coefficient or Spearman's correlation coefficient. RESULTS: There was a significant relationship between tonsilloliths on CT and the extent of the bone defect on panoramic radiographs (Spearman's correlation coefficient, r = 0.648, p = 0.043). In addition, there was a significant difference in the extent of the bone defect caused by periodontitis between subjects with and without tonsilloliths in the 60 to 69-year-old group (Mann-Whitney U test, p = 0.025), 70 to 79-year-old group (Mann-Whitney U test, p = 0.002), and 80 to 89-year-old group (Mann-Whitney U test, p = 0.022), but not in other age groups (Mann-Whitney U test: under 9-year-old group, p = 1.000; 10 to 19-year-old group, p = 1.000; 20 to 29-year-old group, p = 0.854; 30 to 39-year-old group, p = 0.191, 40 to 49-year-old group, p = 0.749; 50 to 59-year-old group, p = 0.627; ≥90-year-old group, p = 1.000). CONCLUSIONS: The presence of tonsilloliths was related to the extent of periodontitis because the structures were responding dynamically.

Association Between the Use of Midazolam During Cardiac Anesthesia and the Incidence of Postoperative Delirium: A Retrospective Cohort Study Using a Nationwide Database.

OBJECTIVE: To evaluate the association between the intraoperative administration of midazolam and the incidence of postoperative delirium in patients undergoing cardiac surgery. DESIGN: Retrospective observational cohort study. SETTING: The Japanese Diagnosis Procedure Combination database. PARTICIPANTS: Patients aged 65 years and older who underwent cardiovascular surgery (excluding transcatheter surgeries, multiple surgeries per admission, and preoperative delirium) between April 1, 2015, and October 31, 2019. MEASUREMENTS AND MAIN RESULTS: Patients who received midazolam (midazolam group) were compared with those who did not receive midazolam (no midazolam group). The primary outcome was the incidence of postoperative delirium. The secondary outcomes were the incidence of postoperative nausea and vomiting, mortality, and duration of intensive care unit stay and hospitalization. Propensity scores were estimated using logistic regression based on the covariates. The outcomes were compared using stabilized inverse probability of treatment-weighting analyses. Among the 16,185 patients analyzed, 10,633 (65.7%) received midazolam. No significant differences were observed in the incidences of postoperative delirium (odds ratio [OR] 0.95; 95% CI 0.87-1.03; p = 0.21) and hospital mortality (OR 0.92; 95% CI 0.76-1.11; p = 0.39) between the groups; however, the midazolam group had slightly longer durations of intensive care unit stay (3.5 [3.5-3.6] v 3.3 [3.3-3.4] days, p < 0.001) and hospitalization (31.5 [31.1-31.9] v 29.4 [28.8-29.9] days, p < 0.001), and slightly lower incidences of postoperative nausea and vomiting (OR 0.92; 95% CI 0.85-0.99; p = 0.03). The sensitivity analyses supported these results. CONCLUSIONS: Intraoperative administration of midazolam may not induce postoperative delirium in patients undergoing cardiac surgery.

Comparison of total intravenous with inhalational anesthesia in terms of postoperative delirium and complications in older patients: a nationwide population-based study.

PURPOSE: Postoperative delirium incidences are increasing in older adults. A Cochrane Review found no significant difference in the incidence of postoperative delirium between total intravenous anesthesia (TIVA) and inhalational anesthesia (IA). This study evaluated the differences in postoperative delirium and morbidity between patients who underwent either TIVA or IA. METHODS: A nationwide Japanese inpatient database was used to retrospectively compare differences in postoperative delirium and composite morbidity between patients older than 65 years, who underwent general anesthesia (TIVA or IA). The primary outcome was postoperative delirium. The secondary outcomes were: morbidity incidence, length of hospital stay, and mortality. A 1:3 propensity score analysis of patients who underwent all surgical procedures was conducted according to covariates, to calculate odds ratios and their 95% confidence intervals (CIs). Sensitivity analyses were conducted using an instrumental variable analysis of the proportion of TIVA by hospital scale, stabilized inverse probability of treatment weighting analyses, limiting the definitions of postoperative delirium, and subgroup analysis. RESULTS: Of 738,600 patients, 149,540 received TIVA and 589,060 received IA. After 1:3 propensity score matching, the adjusted odds ratios for postoperative delirium and composite morbidity were 0.93 (95% CI 0.91-0.95) and 0.94 (95% CI 0.90-0.97), respectively, for TIVA concerning IA. There were no differences in the length of the intensive care unit and hospital stay, or hospital mortality. The findings were consistent with the sensitivity analyses. CONCLUSIONS: This study demonstrated that TIVA was related to a slightly decreased postoperative delirium and incidence of morbidity compared to IA.

The usefulness of Smart Pilot View for fast recovery from desflurane general anesthesia.

INTRODUCTION: Smart Pilot View (SPV) (Dräger Medical) provide information about the estimated drug effect of anesthetic drugs. We conducted a prospective randomized trial to evaluated the recovery time in SPV-guided general anesthesia compared with usual practice in patients with desflurane general anesthesia. METHOD: Thirty-four American Society of Anesthesiologist's physical status I-II patients scheduled for elective surgery under general anesthesia were enrolled in the study. The patients were allocated to one of the following two groups: the Smart Pilot View group (group SPV) or the control group (group C). General anesthesia was induced by propofol and maintained by desflurane end-tidal concentration of 4.2%. During the procedure, desflurane concentration was adjusted to maintain BIS values between 40 and 60 and above MAC 90. In group SPV, desflurane concentration and infusion rate of remifentanil were decreased to achieve MAC 90 about 10 min before the end of the procedure. In group C, the desflurane concentration and infusion rate of remifentanil were maintained unchanged until the end of the procedure. RESULTS: Fifteen patients were enrolled in group C, and seventeen of these were enrolled in group SPV. The time taken for the opening of the patient's eyes was 292 ± 53 s in group C and 218 ± 44 s in group SPV. The time taken for recovery of orientation was 451 ± 100 s in group C and 316 ± 57 s in group SPV. Both times were significantly faster in the group SPV. CONCLUSION: Smart Pilot View guided anesthesia enabled faster recovery from desflurane general anesthesia.

Changes in tonsillolith characteristics detected in a follow-up CT study.

BACKGROUND: Tonsilloliths are related clinically to halitosis and tonsillar abscess. However, the dynamics of tonsilloliths over time are unknown. The aim of the study was to evaluate change in the characteristics of tonsilloliths in a time-dependent fashion by follow-up computed tomography (CT). METHODS: Tonsilloliths were analyzed in 326 CT scan pair sets of initial and at least two follow-up CT examinations of patients with whole palatine tonsils and various diseases of the oral and maxillofacial regions. RESULTS: Over the follow-up period, 12.1% of tonsilloliths disappeared. Approximately 26.1% of tonsilloliths changed in size during follow-up, mostly increasing in size. In tonsilloliths that showed enlargement, the mean (± standard deviation) growth rate was 0.61 ± 0.41 mm per year. Approximately 37.3% of tonsilloliths changed position during the follow-up period; of these, movement was toward the respiratory tract in 92% at a mean rate of - 1.38 ± 1.59 mm per year. The calcification levels of almost all tonsilloliths showed dynamic change: HU number increased in 84.3% and decreased in 12.7% of tonsilloliths over the follow-up period. The mean rate of HU increase was 63.8 ± 96.3 HU/year, and the mean rate of HU decrease was - 38.4 ± 66.8 HU/year. CONCLUSIONS: The calcification levels of all tonsilloliths showed dynamic fluctuation, and a tendency for excretion of tonsilloliths from the body. Their dynamics over time suggest that tonsilloliths may be in a permanently active phase which functions to remove foreign matter.

Comparison of Lumbar Kinematics with a History of Low Back Pain During Baseball Hitting.

The purpose of this study was to examine the influence of a history of low back pain (LBP) on pelvic and lumbar kinematics during baseball hitting. Twenty collegiate male baseball players (age, 21±1 years; height, 172.8±4.7 cm; weight, 72.7±6.2 kg; baseball experience, 13±1 years) performed 5 bat swings. Participants were categorized into the LBP group (n=10) or control group (n=10) based on having experienced lumbar spine pain due to bat swing that lasted more than 24 h within the last 12 months. Three-dimensional kinematic data of the pelvis and lumbar spine during bat swing were measured. Two-way ANOVAs were used to compare pelvic and lumbar kinematics throughout the bat swing between groups, and independent t-tests were used to compare the other outcomes between groups. There was a significant main effect between groups in lumbar flexion angle throughout the bat swing (p=0.047). The mean lumbar flexion angle of the LBP group throughout the bat swing was less than that of the control group. Additionally, the peak angular velocity of lumbar flexion of the LBP group was significantly faster than that of control group (p=0.047). These results can be helpful for longitudinal studies that identify the risk factors of LBP due to bat swing.

Perseus A500 enables faster recovery from desflurane general anesthesia.

PURPOSE: The Dräger Perseus A500 (Perseus) anesthetic workstation has been designed with a lower internal volume. We evaluated the recovery time following general anesthesia using the Perseus workstation compared with that using the conventional Dräger Fabius Plus workstation. METHODS: Following approval by our institutional research ethics committee, 50 patients receiving elective surgery under general anesthesia were enrolled in the study. Written informed consent was obtained from each patient. The patients were divided into the Perseus group and a control group. The Perseus anesthesia workstation was used for the Perseus group, and the Fabius Plus was used for the control group. General anesthesia was maintained with a 4.2% end-tidal concentration of desflurane, remifentanil, fentanyl, and regional anesthesia. After the surgical procedure, the administration of desflurane was discontinued. The inspiratory and expiratory desflurane concentration, time taken for patients to open their eyes, and the time taken to extubate the trachea after discontinuation of anesthetics were recorded. RESULTS: The inspiratory and expiratory desflurane concentration after the administration of desflurane was discontinued was lower in the Perseus group. Moreover, the time taken for patients to open their eyes was statistically significantly quicker in the Perseus group when compared with the control group: 284 ± 60 vs 325 ± 43 s, respectively. The time taken for extubation was also statistically significantly quicker in the Perseus group when compared with the control group: 350 ± 67 vs 388 ± 62 s, respectively. CONCLUSIONS: We demonstrate in this study that Perseus enables the faster wash-out of anesthetics and faster recovery of patients after general anesthesia.

Lumbar lordosis angle and trunk and lower-limb electromyographic activity comparison in hip neutral position and external rotation during back squats.

[Purpose] To compare the lumbar lordosis angle and electromyographic activities of the trunk and lower-limb muscles in the hip neutral position and external rotation during back squats. [Subjects and Methods] Ten healthy males without severe low back pain or lower-limb injury participated in this study. The lumbar lordosis angle and electromyographic activities were measured using three-dimensional motion-capture systems and surface electrodes during four back squats: parallel back squats in the hip neutral position and external rotation and full back squats in the hip neutral position and external rotation. A paired t-test was used to compare parallel and full back squats measurements in the hip neutral position and external rotation, respectively. [Results] During parallel back squats, the average lumbar lordosis angle was significantly larger in hip external rotation than in the hip neutral position. During full back squats, lumbar erector spinae and multifidus activities were significantly lower in hip external rotation than in the hip neutral position, whereas gluteus maximus activity was significantly higher in hip external rotation than in the hip neutral position. [Conclusion] The back squat in hip external rotation induced improvement of lumbar kyphosis, an increasing of the gluteus maximus activity and a decrease of both lumbar erector spinae and multifidus activities.

Piriformis electromyography activity during prone and side-lying hip joint movement.

[Purpose] To measure electromyographic activity of the piriformis using fine-wire electrodes during 7 hip movements. [Subjects and Methods] Eleven healthy men, without severe low back pain or lower limb injury, participated in this study. Fine-wire electrodes were inserted into the piriformis and surface electrodes were attached to the muscles in the hip region and the trunk muscles on the dominant arm side. Electromyographic signal amplitude was measured during 7 hip movements: side-lying external rotation in hip neutral position, side-lying abduction in hip neutral position, side-lying abduction in hip external rotation, side-lying abduction in hip internal rotation, prone extension in hip neutral position, prone extension in hip external rotation, and prone extension in hip internal rotation. Repeated-measures one-way analysis of variance was used to examine electromyographic activity in each of the 7 hip movements. [Results] Piriformis electromyographic activity was highest during prone hip extension in external rotation. Both the superior and inferior portions of the gluteus maximus were also highly activated during prone hip extension in external rotation. [Conclusion] Prone hip extension in external rotation induced high electromyographic activity in the piriformis and superior and inferior gluteus maximus muscles.

Dissection of the posterior wall by guide-wire during internal jugular vein catheterization.

We report a case of posterior wall hematoma formation in the internal jugular vein after the puncture of central vein. An 82-year-old woman was scheduled for laparotomy for an abdominal incisional hernia. After induction of general anesthesia, we performed central venous catheterization via the right internal jugular vein under ultrasound guidance in the short-axis view and out-of plane technique. The ultrasound view after insertion of a guide-wire revealed a hematoma-like space on the posterior wall of the vein. We removed and reinserted the guide-wire. This time, insertion of the wire and catheter was uneventful. Seven days after the surgery, no hematoma-like space was found in the vein. The malposition of the guide-wire was detected before dilation, which enabled us to avoid complications in this case. We should note that the confirmation of guide-wire placement in the vein is important during ultrasound-guided central venous catheterization.

Identification and adjustment of experimental occlusal interference using functional magnetic resonance imaging.

BACKGROUND: The purpose of this study was to use functional magnetic resonance imaging (fMRI) to quantify changes in brain activity during experimental occlusal interference. METHODS: Fourteen healthy volunteers performed a rhythmical tapping occlusion task with experimental occlusal interference of the right molar tooth at 0 mm (no occlusion), 0.5 mm, and 0.75 mm. The blood-oxygen-level dependent (BOLD) signal was quantified using statistical parametric mapping and compared between rest periods and task periods. RESULTS: In tapping tasks with experimental occlusal interference of 0.75 mm or 0.5 mm, there was clear activation of the contralateral teeth-related primary sensory cortex and Brodmann's area 46. At 0 and 30 minutes after removal of the experimental occlusal interference, the activation clearly appeared in the bilateral teeth-related primary sensory cortices and Brodmann's area 46. At 60 minutes after the removal of the experimental occlusal interference, the activation of Brodmann's area 46 had disappeared, and only the bilateral teeth-related primary sensory cortices were active. CONCLUSIONS: The present results suggest that adjustments for experimental occlusal interference can be objectively evaluated using fMRI. We expect that this method of evaluating adjustments in occlusal interference, combined with fMRI and the tapping task, could be applied clinically in the future.

Development and validation of a machine learning model to predict postoperative delirium using a nationwide database: A retrospective, observational study.

STUDY OBJECTIVE: Postoperative delirium is a neuropsychological syndrome that typically occurs in surgical patients. Its onset can lead to prolonged hospitalization as well as increased morbidity and mortality. Therefore, it is important to promptly identify its signs. This study aimed to develop and validate a machine learning predictive model for postoperative delirium using extensive population data. DESIGN: Retrospective observational study. SETTING: Japanese Diagnosis Procedure Combination inpatient data. Data were used for internal (2016.4-2018.12) and temporal validation (2019.01-2019.10). PATIENTS: Patients aged ≥65 years who underwent general anesthesia for surgical procedure. MEASUREMENTS: The primary outcome was postoperative delirium, which was defined as a condition requiring newly prescribed antipsychotic drugs or assignment of the corresponding insurance claim code after the date of surgery. We trained and tuned the optimal machine-learning model through 10-fold cross-validation using the selected optimal area under the receiver operating characteristic curve (AUC) value. In the temporal validation, we measured the performance of our model. MAIN RESULTS: The analysis included 557,990 patients. The light-gradient boosting machine models showed a higher AUC value (0.826 [95% confidence interval (CI): 0.822-0.829]) than the other models. Regarding performance, the model had a recall value of 0.124 (95% CI: 0.119-0.129) and precision value of 0.659 (95% CI: 0.641-0.677]). This performance was sustained in the temporal validation (AUC, 0.815 [95% CI: 0.811-0.818]). At a sensitivity of 0.80, the model achieved a specificity of 0.672 (95% CI: 0.670-0.674]), a negative predictive value of 0.975 (95% CI: 0.974-0.975), and a positive predictive value of 0.176 (95% CI: 0.176-0.179). CONCLUSIONS: Using extensive Diagnostic Procedure Combination data, we successfully created and validated a machine learning model for predicting postoperative delirium. This model may facilitate prediction of postoperative delirium.

The potential positive effect of periodontal treatment on brain function activity using functional magnetic resonance imaging analysis.

Background/purpose: There are reports on the relationship between periodontal treatment and the whole body. The purpose of the present study was to investigate the effect of periodontal initial treatment on brain function activity by improving periodontal tissue and the occlusal status of subjects with periodontitis. Materials and methods: The subjects were 13 patients with periodontitis. Following the patient's informed written consent, the periodontal initial treatment provided to the patient included tooth brushing instruction, scaling and root planning, however, occlusal adjustment was not performed at this stage. Periodontal examination, occlusal force examination and fMRI results were also evaluated at the initial and the reevaluation examinations. Results: After the periodontal initial treatment had been performed, periodontal tissue had significantly improved. In addition, cerebral blood flow in the insula and primary motor cortex was also improved, as confirmed by fMRI. Conclusion: This result suggests that the periodontal ligament has recovered and the periodontal ligament neuron have been further subjected to clenching in the insula.

Imaging characteristics of gubernaculum tracts in patients with cleidocranial dysplasia: a computed tomography study.

OBJECTIVES: To elucidate the imaging characteristics of the gubernaculum tract (GT) in patients with cleidocranial dysplasia (CCD) as visualized with computed tomography (CT). STUDY DESIGN: This was a retrospective analysis of the presence and shape of GTs of unerupted permanent teeth and supernumerary teeth on CT in 9 patients with CCD. RESULTS: The overall GT detection rate for unerupted permanent teeth was 83.5% (81/97), with no significant difference between permanent teeth without and with adjacent supernumerary teeth (P = .414). The overall GT detection rate for unerupted supernumerary teeth was 83.1% (49/59). Of the 156 total unerupted teeth analyzed, 83.3% (130/156) were judged to have GTs. No significant difference in detection rate of GTs was found between permanent and supernumerary teeth (P > 0.999). A composite morphology consisted of a single GT for a permanent unerupted tooth with 1 or 2 supernumerary teeth in which the dental follicles of the permanent and supernumerary teeth were confluent. In total, 44 groups consisted of 1 permanent and 1 or 2 supernumerary teeth; 79.5% (35/44) had GTs. CONCLUSIONS: A specific composite structure of GTs and dental follicles may signify that 2 or 3 teeth are derived from a single dental lamina in patients with CCD. In such cases, tooth eruption may fail due to the presence of only 1 GT for multiple teeth.

Comparison of the distribution of the Bartholin and/or Rivinus salivary ducts assessed with magnetic resonance-sialography in patients with ranula and in healthy subjects.

Background: The distribution and drainage of the sublingual gland ducts have various patterns that might be related to sublingual gland-related diseases, including ranula. This study aimed to elucidate the characteristics of the distribution of Bartholin and/or Rivinus ducts in patients with ranula using magnetic resonance (MR) sialography. Methods: In this retrospective cross-sectional study, the distributions and drainage patterns of sublingual gland ducts on MR sialography were classified in 74 subjects without sublingual gland-related disease as confirmed by both medical history and clinical examination and 15 patients with ranula, respectively. All patients had visited Kyushu Dental University Hospital from July 2015 to June 2022 to undergo MR imaging. Data on the distributions and drainage patterns of the sublingual gland ducts, including the characteristics of the Bartholin and/or Rivinus ducts, were then statistically compared between subjects without sublingual gland-related disease and patients with ranula. The images were assessed by an experienced oral and maxillofacial radiology specialist certified by the Japanese Society for Oral and Maxillofacial Radiology. The distributions (five groups) and drainage patterns (three patterns) of the sublingual gland ducts on MR sialography were classified in reference to previous studies, with some modifications in all subjects without sublingual gland-related disease and patients with ranula. Results: A significant difference in the distribution of the ducts (P<0.001), with a low number of patients exposing an undetected canal or Rivinius duct, was found in the group of patients with ranula (P<0.05). Regarding drainage patterns, no patient with ranula presented a Rivinius duct only. A significant difference in the drainage patterns of the sublingual gland ducts on MR sialography was observed between subjects without sublingual gland-related disease and patients with ranula (P=0.001). Conclusions: The present results suggest that the distribution of the sublingual gland ducts, mainly, the Bartholin duct, may be related to ranula formation. These findings also demonstrate that MR sialography contributes well to preoperative evaluation and is effective for assessing the complex excretory distribution of the sublingual gland ducts.

Imaging Characteristics of Embedded Tooth-Associated Cemento-Osseous Dysplasia by Retrospective Study.

BACKGROUND: Since there are many differential diagnoses for cemento-osseous dysplasia (COD), it is very difficult for dentists to avoid misdiagnosis. In particular, if COD is related to an embedded tooth, differential diagnosis is difficult. However, there have been no reports on the characteristics of the imaging findings of COD associated with embedded teeth. The aim of the present study was to investigate the occurrence and imaging characteristics of cemento-osseous dysplasia (COD) associated with embedded teeth, in order to appropriately diagnose COD with embedded teeth. METHODS: The radiographs with or without histological findings of 225 patients with COD were retrospectively analyzed. A retrospective search through the picture archiving and communication system (PACS) of the Division of Oral and Maxillofacial Radiology of Kyushu Dental University Hospital was performed to identify patients with COD between 2011 and 2022. RESULTS: Fifteen COD-associated embedded mandibular third molars were identified in 13 patients. All 13 patients were asymptomatic. On imaging, COD associated with embedded mandibular third molars appeared as masses that included calcifications around the apex of the tooth. On panoramic tomography, COD showed inconspicuous internal calcification similar to that of odontogenic cysts or simple bone cysts, especially in patients with COD only around the mandibular third molar region. Those with prominent calcification resembled cemento-ossifying fibroma, calcifying epithelial odontogenic tumor, calcifying odontogenic cyst, adenomatoid odontogenic tumor, and so on, as categories of masses that include calcifications on panoramic tomography and computed tomography. CONCLUSIONS: The current investigation is the first to report and analyze the imaging characteristics of COD associated with embedded teeth. It is important to consider the differences between COD and other cystic lesions on panoramic tomography, and the differences between COD and masses that include calcifications on CT.

Increased levels of interleukin-6 in synovial lavage fluid from patients with mandibular condyle fractures: correlation with magnetic resonance evidence of joint effusion.

PURPOSE: The aim of the present study was to investigate the relation between magnetic resonance (MR) evidence of joint effusion and concentrations of proinflammatory cytokines, including interleukin (IL)-1ß and IL-6, in washed-out synovial fluid samples obtained from patients with mandibular condyle fractures. PATIENTS AND METHODS: Twenty-five joints in 23 patients with mandibular condyle fractures were examined. Computed tomography was used to determine the position of the fracture and MR examination was performed in all cases. Twenty-five joints underwent temporomandibular joint (TMJ) irrigation before surgical treatment for the fractures. The detection rates and concentrations of the tested cytokines were determined, and their relations to evidence of joint effusion and positions of the condylar fractures were analyzed. RESULTS: Six TMJ fractures were found in the head, 10 in the upper neck, 4 in the lower neck, and 5 in the subcondyle. MR evidence of joint effusion was observed in 17 of 25 TMJs (68.0%). The detection rate and concentration of IL-6 were significantly higher in patients with MR evidence of joint effusion and those with high condylar fractures. Moreover, there was a correlation between joint effusion grade and IL-6 concentration. CONCLUSIONS: The present findings showed a correlation between MR evidence of joint effusion and concentration of IL-6 in washed-out synovial fluid samples collected from patients with mandibular condyle fractures. These results may provide support for arthrocentesis as a reasonable treatment modality for high condylar fractures.

Prevalence and imaging characteristics of detectable tonsilloliths on 482 pairs of consecutive CT and panoramic radiographs.

BACKGROUND: Recent studies suggest that tonsilloliths are clinically related to halitosis and tonsillar abscess. Based on our empirical knowledge, tonsilloliths are relatively commonly encountered in daily clinical practice. It has been reported that the detection rate of tonsilloliths was under 24% in previous reports, although experience suggests otherwise. The purpose of the study was to evaluate the prevalence and characteristics of tonsilloliths using computed tomography (CT). In addition, the possible causes of low detection rates on panoramic radiographs were evaluated based on comparisons between CT images and panoramic radiographs in order to elucidate the limitations of visualizing the area around the palatine tonsils on panoramic radiographs. METHODS: 482 pairs of CT images and panoramic radiographs were retrospectively assessed with respect to the presence and characteristics of tonsilloliths. In addition, the causes in cases of disagreement between the two modalities were analyzed. RESULTS: The detection rate of tonsilloliths was 46.1% using CT scans, unlike previous reports. The characteristics of tonsillolith were dot-like figures with about 300-500 Hounsfield units within the palatine tonsil under the soft palate. The most common length of tonsilloliths was about 3 or 4 mm. As the subjects aged, the detection rate increased gradually. A significant difference in the tonsillolith detection rate was found between the over and under 40-year-old groups (p < 0.0001). However, the detection rate of tonsilloliths was only 7.3% on panoramic radiographs. A significant correlation was observed between the detection rate of tonsilloliths on panoramic radiographs and CT number (Spearman r = 0.429), size, (Spearman r = 0.318), and number of tonsilloliths (Spearman r = 0.333). CONCLUSION: The present results suggest that tonsilloliths are relatively more common than previously suggested. However, panoramic radiographs detect only a small percentage of palatine tonsilloliths. The low detection rates on panoramic radiographs might be related to the degree of calcification, size, and number of tonsilloliths.