We previously reported that near-infrared hyperspectral imaging enabled the localization of atherosclerotic plaques from outside the vessels, but not the optical characteristics of each histological component. Therefore, the near-infrared spectrum of each component was collected from the sliced section of the human carotid plaque obtained with endarterectomy and the optical characteristics were confirmed in several wavelengths. Based on this information, we assessed the diagnostic accuracy for ex vivo chemogram in each plaque component created with near-infrared spectroscopy (NIRS), using multiple wavelengths. The chemogram projected on the actual image of plaque was created based on light intensity and transmittance change at three wavelengths. The wavelengths that were mainly were 1440, 1620, 1730, and 1930 nm. We evaluated the accuracy of histological diagnosis in chemogram compared with pathological findings, analyzing interobserver agreement with κ-statistics. The chemograms that we created depicted the components of fibrous tissue, smooth muscle, lipid tissue, intraplaque hemorrhage, and calcification. Diagnostic odds ratio in each component was as follows: 259.6 in fibrous tissue, 144 in smooth muscle, 1123.5 in lipid tissue, 29.3 in intraplaque hemorrhage, and 136.3 in calcification. The κ-statistics revealed that four components, excluding intraplaque hemorrhage, had substantial or almost perfect agreement. Thus, this study demonstrated the feasibility of using chemogram focused on specific component during the histological assessment of atherosclerotic plaques, highlighting its potential diagnostic ability. Chemograms of various target components can be created by combining multiple wavelengths. This technology may prove to be useful in improving the histological assessment of plaque using NIRS.

Cranioplasty following decompressive craniectomy is highly associated with complications. Methods for avoiding these complications have been well-documented; however, approaching reconstruction through the previous incision, especially if it was on or very near the bone defect, can sometimes lead to wound dehiscence and infection, with exposure of the artificial bone. For such complicated cases, we propose a multi-staged preparation that includes creating a delayed skin flap for the actual skull reconstruction. Flap was elevated in three stages, with 4 week intervals between each stage to allow for adequate blood supply. Cranioplasty using custom-made implants was then performed. Four patients (age range, 10–25 years) were prepared for skull reconstruction using this technique. During follow-up period for 12 months, no complications, including infections, exposure of the artificial bone, or flap necrosis, were observed. Despite the multiple stages required, we consider that our technique makes a significant contribution to the literature because it suggests a technique for cranioplasty following decompressive craniectomy that may avoid many of the complications following such cranioplasty using current methods.

Tumefactive multiple sclerosis (tumefactive MS) is an atypical variant of MS characterized by a large isolated demyelinating lesion. Because tumefactive MS mimics high grade astrocytoma clinically and radiologically, it is difficult to distinguish between the two using only traditional diagnostic modalities, such as routine magnetic resonance imaging. [¹¹C] methionine positron emission tomography (MET PET) has been known as a useful diagnostic tool for glioma. However, it has not been established as a diagnostic tool for tumefactive MS yet. Therefore, the objective of this study was to evaluate the performance of MET PET in differentiating tumefactive MS from high grade astrocytoma. We studied patients with tumefactive MS [six patients (three men, three women), 7 lesions] and 77 patients with astrocytoma (World Health Organization grade II: 13 patients, grade III: 28 patients, and grade IV: 36 patients), and we compared MET uptake of tumefactive demyelinating lesions and astrocytoma. For MET PET analysis, Lesion/Normal region ratios (L/N ratios) were calculated and compared between tumefactive demyelinating lesions and astrocytoma. On MET PET, the L mean/N ratio of tumefactive MS was 1.18 ± 0.50, which was significantly lower than that of high-grade glioma (astrocytoma grade III: 1.95 ± 0.62, P = 0.006; grade IV: 2.35 ± 0.54, P <0.0001). The L maximum (L max)/N ratio of tumefactive demyelinating lesion was also significantly lower than that of high grade astrocytoma (tumefactive MS: 1.89 ± 0.55; astrocytoma grade III: 3.37 ± 1.36, P = 0.0232; astrocytoma grade IV: 4.35 ± 1.30, P <0.0001). In conclusion, MET PET can help differentiate tumefactive MS from high grade astrocytoma.

Secure reconstruction in transsphenoidal surgery (TSS) is important for the prevention of the major and serious complication of postoperative cerebrospinal fluid (CSF) leak. Although abdominal fat can be safely and effectively used as a reconstruction tissue, harvesting it from the abdominal wall is traumatic and invasive, resulting in cosmetic problems. In this report, we present a method of harvesting abdominal fat using a minimally invasive liposuction technique to avoid cosmetic issues. Since 2016, we have been using fat harvested from the abdominal wall by suctioning with a dedicated syringe for reconstruction after TSS in selected cases. The liquefied fat obtained by the liposuction technique was wrapped with an oxycellulose sheet and changed its form to what we termed “fatty candy”. In this form, the fat maintained its configuration and could be handled almost as easily as a conventional fat graft. In our experienced series, there was no case with wound complication nor postoperative or late-onset CSF leak during a postoperative follow-up of at least 3 months. The fat harvested by this simple and minimally invasive liposuction technique can be expected to provide an autologous graft that is adequate not only for prevention of cosmetic problems but also for prevention of postoperative CSF leak.

Post-traumatic striatocapsular infarction is extremely rare and has been described only within the vascular territory of the perforating arteries originating from the middle cerebral artery (MCA). We recently encountered a patient presenting with unilateral multifocal striatocapsular hemorrhagic infarctions following mild head injury. This 25-year-old female was admitted to our trauma center after a motorcycle accident. Initial brain computed tomography and magnetic resonance (MR) imaging showed multifocal acute hemorrhagic infarctions with a clustering in the right caudate head, anterior limb of internal capsule, and globus pallidus. MR angiography and digital subtraction angiography showed suspicious luminal irregularities of the lenticulostriate arteries of the right MCA. Vessel wall MR images (VWI) did neither indicate intramural hematoma nor wall enhancement in the right MCA, suggesting dissection. However, VWI showed the passages of each lenticulostriate artery supplying each infarction site. Therefore, based on both conventional images and VWI, we postulate that this patient’s post-traumatic multifocal striatocapsular hemorrhagic infarctions were caused by damage to multiple lenticulostriate arteries.