Maki Ohtani

Immunohistochemical localization of inducible nitric oxide synthase in synovial tissue of human temporomandibular joints with internal derangement

The expression and distribution of inducible nitric oxide synthase (iNOS) was examined in 12 samples of human temporomandibular joint (TMJ) with internal derangement (ID) and four control specimens. In the diseased joints, strong or definite iNOS reactivity was expressed in synovial lining and endothelial cells; weaker activity was present in synovial fibroblasts. In contrast, although there was weak expression of iNOS in synovial fibroblasts and endothelial cells in the two control specimens, there was no iNOS staining in the synovial lining cell layers. This original report that iNOS is expressed in the synovial tissue of the temporomandibular joint indicates that nitric oxide is produced locally at least in the synovial lining in these joints when affected by internal derangement.

Two adult cases of congenital atresia of the left coronary ostium—comparison of a sudden death case with a long-term survival case

We present two extremely rare autopsy cases with atresia of the left coronary ostium. Case 1 was a 34-year-old man who died of sudden cardiac causes with localized acute subendocardial infarction and Case 2 was an 82-year-old woman who died from non-cardiac causes. In both cases, a string-like small left main trunk that was located in its normal position was found; however, the orifice of the left coronary artery was absent in both cases. The collateral artery (CA), whose caliber was smaller than that of the proximal left descending artery (LAD), arose from the right coronary sinus and was anastomosed with the distal LAD. However, it was only in Case 1 that the CA showed an acute angle of take-off from the aorta, subsequently coursing between the root of the aorta and the pulmonary trunk, with possible mechanical compression by these two arteries. These two cases suggest that atresia of the left coronary ostium is developmentally and anatomically different from single coronary artery or left coronary artery arising from the opposite sinus of valsalva. Atresia of the left coronary ostium is considered to be an important differential diagnosis as a cause of sudden death, not only in the pediatric population but also in adults. The caliber and/or other anatomical features of the CA may predominantly dictate the clinical course of patients with atresia of the left coronary ostium.

Magnetic Resonance Evidence of Joint Effusion of the Temporomandibular Joint After Fractures of the Mandibular Condyle: A Preliminary Report

Abstract To investigate the clinical significance of magnetic resonance (MR) evidence of joint effusion of the temporomandibular joint after mandibular condylar fractures, magnetic resonance imaging (MRI) was performed on 18 joints in 15 patients with either unilateral or bilateral mandibular condylar fractures using a 1.5 Tesla MRI scanner (Signa, General Electric, Milwaukee, WI). MR evidence of joint effusion was evaluated and compared with the types and the positions of the fractures. MR evidence of joint effusion was observed in 11 of 18 TMJs, which was 61% of the condylar fractures. It appeared more frequently after fractures with dislocation than those without dislocation (p<0.05). In addition, MR evidence of effusion appeared more frequently in TMJs after high condylar fractures (head to upper neck) than low condylar fractures (lower neck to subcondylar) (p<0.05). These findings indicate that MR evidence of joint effusion may serve as a marker for the detection of severe intra-articular damage to the TMJ after mandibular condyle fractures.

Spinal hyperostosis as an important sign indicating spine injuries on postmortem computed tomography

Although spine injuries are not always detectable on postmortem computed tomography (PMCT), spinal hyperostosis, an important risk factor for spine injury, is relatively easily detectable on PMCT. We therefore examined the utility of the detection of spinal hyperostosis on PMCT as an indicator of spine injury. Full-body PMCT images of 88 autopsy cases with a bruise on the face or forehead but no identifiable skull fracture were reviewed prior to autopsy for the identification and classification of spinal hyperostosis. Spine injuries were observed in 56.0% of cases with spinal hyperostosis and 1.6% of cases without spinal hyperostosis. Among the cases with spinal hyperostosis, spine injuries were observed in 66.7% of cases at stage 2 or 3 and in 88.9% of cases at stage 3. Spine injuries were diagnosed on PMCT in 33.3% of cases prior to autopsy. A significant association was found between spinal hyperostosis and presence of spine injury that cannot be detected on PMCT, indicating that the identification of spinal hyperostosis on PMCT may assist in detecting spine injuries. This finding suggests that investigation of the presence of spine injury based on the identification of spinal hyperostosis on PMCT may assist in determining the correct cause of death by autopsy.

Characterization of bruises using ultrasonography for potential application in diagnosis of child abuse

To protect children from abuse, it is important to identify victims at an early date, but diagnosis is often difficult. We used ultrasonography for objective examination of bruises arising from subcutaneous hemorrhages, and determined whether we could precisely measure the depth and thickness of a subcutaneous hemorrhage. We compared macroscopic findings, microscopic findings and ultrasonographic images of 10 bruises in forensic autopsy cases. In addition, we measured chronologic changes in subcutaneous hemorrhages using ultrasonography of 16 bruises in healthy volunteer children. Mild or moderate subcutaneous hemorrhages spreading along the fibrous partition in subcutaneous fatty tissue were observed by histological examination. There was a thickened fibrous partition or an isoechoic or hyperechoic area in the ultrasonographic images. A good correlation between the thickness of the subcutaneous hemorrhages by macroscopic examination and by ultrasonographic imaging was found in postmortem cases. We were also able to confirm objectively that the thickness of the subcutaneous hemorrhage of healthy children decreased with time. It is possible to measure the depth from the skin surface to the subcutaneous hemorrhage, and the thickness of the subcutaneous hemorrhage accurately using ultrasonography. Thus, the age of a bruise can be estimated more precisely using information on the subcutaneous hemorrhage from ultrasonography in addition to established evaluations by the naked eye and by spectrophotometry.

Detection of carbon monoxide poisoning that occurred before a house fire in three cases

In our institutes, we perform a quantitative evaluation of volatile hydrocarbons in post-mortem blood in all fatal fire-related cases using headspace gas chromatography mass spectrometry. We previously reported that benzene concentrations in the blood were positively correlated with carbon monoxide-hemoglobin (CO-Hb) concentrations in fire-related deaths. Here, we present 3 cases in which benzene concentrations in the blood were not correlated with CO-Hb concentrations. A high CO-Hb concentration without a hydrocarbon component, such as benzene, indicates that the deceased inhaled carbon monoxide that was not related to the smoke from the fire. Comparing volatile hydrocarbons with CO-Hb concentrations can provide more information about the circumstances surrounding fire-related deaths. We are currently convinced that this is the best method to detect if carbon monoxide poisoning occurred before a house fire started.

Survey of dental diseases in forensic autopsy cases.

Forensic odontology plays an important role in the age estimation of a corpse. However, some cases exhibit a large margin of error when using conventional morphological methods. The final purpose of this study was to survey dental diseases to find the factors that result in errors in age estimation. First, we surveyed dental status related to dental caries in forensic autopsy cases to examine their characteristics. We investigated 335 forensic autopsy cases with accurate age and gender information available from autopsy and police reports. We assessed the number of teeth with caries, including the number of present teeth, missing teeth, sound teeth, treated teeth, untreated teeth, and the total number of carious teeth (DMF teeth: decayed, missing, and filled teeth).Then, each mean number of teeth from autopsy cases was compared with that from the results of a control survey of dental disease performed by Akita Prefecture. The autopsy cases, mainly in their 50s, showed a significantly higher incidence of DMF teeth, missing teeth, and untreated teeth. They also showed lower incidence of treated teeth. The more severe carious status in the autopsy cases suggested that they did not regularly visit dental clinics while they were alive. We will continue to analyze their past physical disease histories, the causes of death, and their antemortem lifestyles to find the factors that lead to incorrect age estimation.

Visualization of old bruises in children: Use of violet light to record long-term bruises

When a child consultation center evaluates abused children, evidence of the abuse must be documented. Children who have suffered physical abuse often have bruises, which cannot be confirmed by visualization when the bruise has healed. In forensics, a method to confirm an old bruise by ultraviolet radiation is possible. However, long-term ultraviolet exposure can be harmful. In this study, we observed 15 bruises on healthy volunteer children using four kinds of light sources, including ultraviolet radiation, over time. The violet light source enabled observation of a bruise for a longer time than ultraviolet radiation. Although other studies have shown that violet light is superior for enhancing bruises, this is the first report to evaluate data concerning the ability to identify bruises over time in living children. These results might help to identify evidence of past violence suffered by children.

Three cases of suprachoroidal hemorrhage associated with chest compression or asphyxiation and detected using postmortem computed tomography

We report 3 cases of suprachoroidal hemorrhage (SCH) found to be triggered by increased intrathoracic pressure and detected using postmortem computed tomography (PMCT). Case 1 was a man aged in his 50s who was found dead at a landslide site. The autopsy showed clogging of the upper respiratory tract with soil debris from the landslide. The cause of death was determined to be asphyxia. PMCT showed SCH in both eyes, which was believed to be caused by chest compression or choking on the soil debris from the landslide. Case 2 was a woman aged in her 60s who was found dead in the sea. The autopsy revealed injuries primarily to her chest. We concluded that the cause of death was drowning. PMCT showed SCH in her right eye that was believed to be caused by chest compression. Case 3 was a woman aged in her 80s who was buried in a snowdrift and potentially died from hypothermia. PMCT showed SCH in both eyes, which was considered to be from an increase in intrathoracic pressure that might have been caused by the burial in the snow. Histological findings showed serous retinal detachment associated with retinal pigment epithelium damage due to SCH, which indicated that she was alive for several hours after the onset of SCH. The increase in intrathoracic pressure caused by dyspnea or chest compression was considered responsible for the onset of SCH in all of the present cases. PMCT might assist with the differential diagnosis of traumatic asphyxiation by SCH.

Four cases of orbital hyperdensity identified by postmortem computed tomography.

Postmortem computed tomography (PMCT) has become a common examination method in the field of forensic medicine. Head computed tomography provides information of the orbit and eyes, and forensic pathologists may come across abnormal intraocular findings of cadavers upon PMCT. Here, we present four cases in which we identified orbital hyperdensity by PMCT. The first case showed calcified senile scleral plaques (CSSP), whereas the second case showed foreign bodies in the palpebral fissure, which resembled CSSP upon PMCT. The third case showed signs of silicone oil injection in the eye, while the fourth case showed bilateral phthisis bulbi. In the first case, the presence of CSSP was found to be helpful for age estimation, whereas the findings of cases 3 and 4 aided in the personal identification of the subjects. As demonstrated by these cases, intraocular PMCT findings may provide highly useful information, and correct interpretation of the intraocular PMCT findings by forensic pathologists is hence crucial.