OBJECTIVE: We hypothesized that the risk of infections after primary cranioplasty in adult patients who underwent craniectomies for non-infection-related indications are no different when performed early or delayed. We tested this hypothesis in a prospective, multicenter, cohort study.
METHODS: Data were collected prospectively from 5 neurosurgical centers in the United Kingdom, Malaysia, Singapore, and Bangladesh. Only patients older than 16 years from the time of the non-infection-related craniectomy were included. The recruitment period was over 17 months, and postoperative follow-up was at least 6 months. Patient baseline characteristics, rate of infections, and incidence of hydrocephalus were collected.
RESULTS: Seventy patients were included in this study. There were 25 patients in the early cranioplasty cohort (cranioplasty performed before 12 weeks) and 45 patients in the late cranioplasty cohort (cranioplasty performed after 12 weeks). The follow-up period ranged between 16 and 34 months (mean, 23 months). Baseline characteristics were largely similar but differed only in prophylactic antibiotics received (P = 0.28), and primary surgeon performing cranioplasty (P = 0.15). There were no infections in the early cranioplasty cohort, whereas 3 infections were recorded in the late cohort. This did not reach statistical significance (P = 0.55).
CONCLUSIONS: Early cranioplasty in non-infection-related craniectomy is relatively safe. There does not appear to be an added advantage to delaying cranioplasties more than 12 weeks after the initial craniectomy in terms of infection reduction. There was no significant difference in infection rates or risk of hydrocephalus between the early and late cohorts.
METHODS: Miri General Hospital is a remote center in Sarawak, Malaysia, serving a population with difficult access to neurosurgical services. Two neurosurgeons were stationed here on a rotational basis every fortnight during the pandemic to handle neurosurgical cases. Patients were triaged depending on their urgent needs for surgery or transfer to a neurosurgical center and managed accordingly. All patients were screened for potential risk of contracting COVID-19 prior to the surgery. Based on this, the level of personal protective equipment required for the health care workers involved was determined.
RESULTS: During the initial 6 weeks of the Movement Control Order in Malaysia, there were 50 urgent neurosurgical consultations. Twenty patients (40%) required emergency surgery or intervention. There were 9 vascular (45%), 5 trauma (25%), 4 tumor (20%), and 2 hydrocephalus cases (10%). Eighteen patients were operated at Miri General Hospital, among whom 17 (94.4%) survived. Ninety percent of anticipated transfers were avoided. None of the medical staff acquired COVID-19.
CONCLUSIONS: This framework allowed timely intervention for neurosurgical emergencies (within a safe limit), minimized transfer, and enabled uninterrupted neurosurgical services at a remote center with difficult access to neurosurgical care during a pandemic.
METHOD: DPSC from murine incisors were isolated through either the outgrowth (DPSC-OG) or the enzymatic digestion (DPSC-ED) method. Cells at passage 4 were used in this study. The cells were characterized through morphology and expression of cell surface markers. The cells' doubling time when cultured using different seeding densities was calculated and analyzed using one-way ANOVA and Tukey's multiple comparison post-test. The ability of cells to differentiate to chondrocyte and osteoblast was evaluated through staining and analysis on the matrices secreted.
RESULTS: Gene expression analysis showed that DPSC-OG and DPSC-ED expressed dental pulp mesenchymal stem cell markers, but not hematopoietic stem cell markers. The least number of cells that could have been used to culture DPSC-OG and DPSC-ED with the shortest doubling time was 5 × 10(2) cells/cm(2) (11.49 ± 2.16 h) and 1 × 10(2) cells/cm(2) (10.55 h ± 0.50), respectively. Chondrocytes differentiated from DPSC-ED produced 2 times more proteoglycan and at a faster rate than DPSC-OG. FTIR revealed that DPSC-ED differentiated into osteoblast also secreted matrix, which more resembled a calvaria.
DISCUSSION: Isolation approaches might have influenced the cell populations obtained. This, in turn, resulted in cells with different proliferation and differentiation capability. While both DPSC-OG and DPSC-ED expressed mesenchymal stem cell markers, the percentage of cells carrying each marker might have differed between the two methods. Regardless, enzymatic digestion clearly yielded cells with better characteristics than outgrowth.