Background:Most reports of cadaveric specimen preparation for neurosurgical dissection describe methods using fresh cadavers. Our cultural limitations prevent us from obtaining fresh cadaveric heads.Objective:To study and report on an alternative method of preparation of head specimens for neurosurgical dissection using defrosted cadavers.Materials and Methods:Twenty-four head specimens were procured through the Department of Anatomy, received by donation three to seven days after funeral activity. The specimens were sectioned through the neck, and preserved by refrigeration at a temperature of -10°C for a period of one week to three months prior to preparation. The process began with defrosting the frozen head specimens for 48 hours in a refrigerator, in which the temperature was controlled within the range of -2° to -8°C. The great vessels were identified and cannulated. These were then irrigated with tap water until clear, following which colored silicone was injected. The specimens were preserved in 95% ethyl alcohol, and were assessed for quality one week after the preparation process. They were then re-assessed at monthly intervals for 12 months.Results:When compared with specimens prepared from fresh cadavers, our method provided similar quality specimens for dissection. The scalp and muscles of all specimens remained soft. The vasculature was good, and the colored silicone made identification easy. The brain tissues were soft and easily retracted, and still in good condition for dissection after a long preparation period (12 months).Conclusion:The head specimens prepared with this method were of good quality for dissection, and were comparable in quality to those prepared from fresh cadavers as in published methods. We were thus able to provide a suitable substitute to fresh head specimens in situations where access to fresh cadavers is unavailable.

Fetus in fetu (FIF) is an extremely rare anomaly featuring a monozygotic, diamniotic, parasitic twin, enclosed within its host twin. It is characterized by the presence of vertebrae and well-developed organs in a fetiform mass. Only 18 cases of intracranial FIF have been published. Of them, only five cases were prenatally detected. This study prenatally demonstrated triplet FIFs at 31 weeks within amniotic-like sac in the fetal skull, consisting of multiple well-defined organs. The FIF attached to the host twin via body stalk containing a single main feeding artery and vein, representing umbilical vessels. Surgical removal was performed at the age of two months. Pathological examination showed the triplet FIF, consisting of numerous well-developed organs (musculocutaneous-skeletal, nervous, respiratory, gastrointestinal systems etc.), with soft tissue/skin coverings, but no vertebral body was seen. Molecular genetic analysis revealed identical genetic mapping among the three FIFs and the host. This case provides strong evidence against Willis's hypothesis but supports Spencer's theory of abnormal twinning.

No abstract

No abstract

Objective Consistency of meningiomas is one of the most important factors affecting the completeness of removal and major risks of meningioma surgery. This study used preoperative magnetic resonance imaging (MRI) sequences in single and in combination to predict meningioma consistency. Methods The prospective study included 287 intracranial meningiomas operated on by five attending neurosurgeons at Chiang Mai University Hospital from July 2012 through June 2020. The intraoperative consistency was categorized in four grades according to the method of surgical removal and intensity of ultrasonic aspirator, then correlated with preoperative tumor signal intensity pattern on MRI including T1-weighted image, T2-weighted image (T2WI), fluid-attenuated inversion recovery (FLAIR), and diffusion-weighted image (DWI), which were described as hypointensity, isointensity, and hyperintensity signals which were blindly interpreted by one neuroradiologist. Results Among 287 patients, 29 were male and 258 female. The ages ranged from 22 to 83 years. A total of 189 tumors were situated in the supratentorial space and 98 were in the middle fossa and infratentorial locations. Note that 125 tumors were found to be of soft consistency (grades 1, 2) and 162 tumors of hard consistency (grades 3, 4). Hyperintensity signals on T2WI, FLAIR, and DWI were significantly associated with soft consistency of meningiomas (relative risk [RR] 2.02, 95% confidence interval [CI] 1.35–3.03, p = 0.001, RR 2.19, 95% CI 1.43–3.35, p < 0.001, and RR 1.47, 95% CI 1.02–2.11, p = 0.037, respectively). Further, chance to be soft consistency significantly increased when two and three hyperintensity signals were combined (RR 2.75, 95% CI 1.62–4.65, p ≤ 0.001, RR 2.79, 95% CI 1.58–4.93, p < 0.001, respectively). Hypointensity signals on T2WI, FLAIR, and DWI were significantly associated with hard consistency of meningiomas (RR 1.82, 95% CI 1.18–2.81, p = 0.007, RR 1.80, 95% CI 1.15–2.83, p = 0.010, RR 1.67, 95% CI 1.07–2.59, p = 0.023, respectively) and chance to be hard consistency significantly increased when three hypointensity signals were combined (RR 1.82, 95% CI 1.11–2.97, p = 0.017). Conclusion T2WI, FLAIR, and DWI hyperintensity signals of the meningiomas was solely significantly associated with soft consistency and predictive value significantly increased when two and three hyperintensity signals were combined. Each of hypointensity signals on T2WI, FLAIR, and DWI was significantly associated with hard consistency of tumors and tendency to be hard consistency significantly increased when hypointensity was found in all three sequences.