Microcervical Foraminotomy for Cervical Juxtafacet Cysts: Case Series and Literature Review.

BACKGROUND: Juxtafacet cysts are located near or contiguous with the facet joints, and their occurrence is rare in the cervical spine. We report 4 cases of cervical juxtafacet cysts operated by microcervical foraminotomy (MCF) or a combination of MCF and laminoplasty. We simultaneously review previously reported cases in terms of location, clinical findings, and surgical technique. METHODS: Among the patients who underwent spine surgery at our hospital from 2015 to 2019, 4 had cervical juxtafacet cysts. The images and clinical records of the patients were retrospectively assessed. Relevant previous English literature was searched and reviewed using PubMed. RESULTS: In our series, all 4 patients presented with unilateral upper extremity muscle weakness preoperatively. Two patients underwent MCF, and the other 2 underwent a combination of MCF and laminoplasty with resection of the cyst. All showed improvement in muscle strength. In previously reported cases, the rate of muscle weakness was high. A review of previous cases showed that 75 of 139 patients had cysts at C7-T1. The most common surgical techniques consisted of a hemilaminectomy or laminectomy with the addition of posterior fusion in 28 patients. The number of male patients was twice that of female patients; however, the male-to-female ratio was almost the same in patients with cysts in C7-T1. On pathological diagnosis, there were 3 times more synovial cysts than ganglion cysts. The percentage of synovial cysts was higher in patients with radiculopathy, and the percentage of ganglion cysts was higher in patients with myelopathy. CONCLUSIONS: Cervical juxtafacet cysts tend to occur in C7-T1 and cause muscle weakness. Surgical therapy is strongly recommended due to good postoperative improvement. CLINICAL RELEVANCE: The results of this study suggest that microcervical foraminotomy for cervical juxtafacet cysts can provide favorable symptomatic improvement.

Prognostic factors for spontaneous spinal epidural hematoma: a multicenter case-control study.

BACKGROUND: To determine the optimal treatment for spontaneous spinal epidural hematoma (SSEH). The aim of this study was to identify factors associated with SSEH. METHODS: In 62 patients with SSEH, several patient-related parameters were analyzed as candidate factors associated with Frankel grade before treatment or at the last follow-up. These parameters were compared between patients with and without surgery. In addition, multivariate ordinal logistic regression analysis was used to identify factors significantly associated with Frankel's grade before treatment or at the last follow-up. RESULTS: There were significant differences in age, location of the hematoma, and Frankel grade before treatment and at the last follow-up between surgical and nonsurgical cases in all patients, but there were no significant differences in any of these parameters when comparing patients with pre-treatment Frankel grade C. The location of the hematoma was significantly associated with the severity of paralysis before treatment. In surgical cases, the time from onset to surgery and the location of the hematoma was significantly associated with the prognosis. When the time from onset to surgery was evaluated using the criteria of 12, 24, and 48 h, 24 and 48 h had a significant impact on the prognosis. In the analysis of nonsurgical cases, only the vertical size of the hematoma was significantly associated with prognosis. CONCLUSION: The time from onset to surgery and the location of the hematoma were prognostic factors in surgical cases, while the vertical size of the hematoma was a prognostic factor in nonsurgical cases.

An off-line automated preconcentration system with ethylenediaminetriacetate chelating resin for the determination of trace metals in seawater by high-resolution inductively coupled plasma mass spectrometry.

A novel automated off-line preconcentration system for trace metals (Al, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in seawater was developed by improving a commercially available solid-phase extraction system SPE-100 (Hiranuma Sangyo). The utilized chelating resin was NOBIAS Chelate-PA1 (Hitachi High-Technologies) with ethylenediaminetriacetic acid and iminodiacetic acid functional groups. Parts of the 8-way valve made of alumina and zirconia in the original SPE-100 system were replaced with parts made of polychlorotrifluoroethylene in order to reduce contamination of trace metals. The eluent pass was altered for the back flush elution of trace metals. We optimized the cleaning procedures for the chelating resin column and flow lines of the preconcentration system, and developed a preconcentration procedure, which required less labor and led to a superior performance compared to manual preconcentration (Sohrin et al.). The nine trace metals were simultaneously and quantitatively preconcentrated from ∼120 g of seawater, eluted with ∼15 g of 1M HNO3, and determined by HR-ICP-MS using the calibration curve method. The single-step preconcentration removed more than 99.998% of Na, K, Mg, Ca, and Sr from seawater. The procedural blanks and detection limits were lower than the lowest concentrations in seawater for Mn, Ni, Cu, and Pb, while they were as low as the lowest concentrations in seawater for Al, Fe, Co, Zn, and Cd. The accuracy and precision of this method were confirmed by the analysis of reference seawater samples (CASS-5, NASS-5, GEOTRACES GS, and GD) and seawater samples for vertical distribution in the western North Pacific Ocean.