Imaging of trochlear nerve schwannomas: a case series and systematic review of the literature.

Purpose Trochlear nerve schwannomas are rare tumors. So far, only 121 cases have been published. We present four new cases, discuss the imaging characteristics and summarize all previously published cases through a systematic review.Methods Four cases, all treated in AZ Sint-Jan Hospital Brugge-Oostende (Belgium), were collected, including their demographic, clinical and radiological data. All MR imaging was performed with the three-dimensional fluid-attenuated inversion recovery (3D-FLAIR), turbo spin echo T1 high-resolution (TSE T1 HR), three-dimensional balanced fast-field echo (3D b-FFE) and three-dimensional T1 black blood (3D T1 black blood) sequence. We compared our findings with the present literature through a systematic literature review in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines.Results Screening with routine unenhanced 3D-FLAIR imaging could identify all schwannomas as hyperintense lesions on the course of the trochlear nerve. The use of 3D T1 black blood sequences was superior in depicting the lesions, while high-resolution 3D b-FFE images enabled us to visualize the anatomic boundaries of the lesions in detail. Most trochlear schwannomas are located in the ambient cistern, at or just below the free edge of the tentorium.Conclusion The majority of trochlear nerve schwannomas are located cisternal and display variable enhancement on contrast administration. 3D-FLAIR imaging is superior in detecting these lesions. Comparison with data collected from previous cases demonstrates the importance of early diagnosis and treatment. Generally, patients with trochlear nerve schwannomas have a good prognosis.

Spontaneous involution of a large pineal cyst: Case report and narrative review.

OBJECTIVE: To illustrate the possibility of spontaneous involution of a pineal cyst, justifying an initial observation strategy in patients without evident mass effect. BACKGROUND: Pineal cysts are frequent radiological findings, with a reported overall prevalence from 0.6% to 40%. Historically, surgery has been reserved for patients with symptoms attributable to a mass effect of the cyst. Despite the high prevalence of pineal cysts, the clinical approach to patients with non-specific symptoms remains controversial. METHODS: We report on the spontaneous involution of a large pineal cyst in a 26-year-old female who presented in our outpatient clinic with transient symptoms of headache and nausea. PubMed and Web of Science databases were scrutinized using a predefined search strategy in accordance with the Population, Intervention, Comparison and Outcome (PICO) set-up using "pineal cyst" and "surgery" as search terms. Only peer-reviewed publications were considered eligible. Titles and abstracts of 1513 manuscripts were screened for relevance. After excluding 1420 publications evaluating non-relevant pathology, the eligibility of the remaining 93 full-text records was further assessed and included if they reported patients with pineal cysts presenting with intractable symptoms without hydrocephalus or Parinaud syndrome, and if they documented on their symptomatology and clinical management. CONCLUSION: Recent case series and reviews report favorable results of surgery in patients with pineal cysts but also a potentially high complication rate. However, the evidence offered by these reports is limited and a placebo effect cannot be ruled out. Therefore, surgery cannot be unequivocally advocated in these patients. Instead, an initial surveillance strategy is advocated. We concur with a previously propounded surveillance strategy of a single follow-up magnetic resonance imaging at 12 months. This case report demonstrates the importance of an initial observation strategy since pineal cysts may also show a spontaneous involution.

Patient-reported outcomes after primary rotating hinge total knee arthroplasty: a multi-centre clinical cohort study.

PURPOSE: Rotating hinge prostheses for total knee arthroplasty (TKA) are mostly used in revision setting; however, evidence on the use of these constrained devices in primary setting is scarce and inconsistent. Therefore, we aimed to evaluate the functional outcomes after third-generation rotating hinge implants in primary TKA with a minimal follow-up of two years in a large dual-centre observational retrospective clinical trial. METHODS: The hospital databases of two centres were searched for primary rotating hinge arthroplasty from January 2007 to January 2015. A minimum follow-up of at least two years was assured. Patients meeting the inclusion criteria were asked to fill out two self-reported functional scores, the Oxford Knee Score (OKS) and Forgotten Joint Score (FJS), to measure the functional status of the knee. RESULTS: In total, 267 primary rotating hinge knee arthroplasties in 242 patients were performed in two centres. The three major indications were axial malalignment (valgus/varus > 15°), 87/267 (33%), persistent ligamentous instability (28%) and neuromuscular disorders (12%). 184 patients with 202 primary rotating hinge knee arthroplasties could be included that provided data of the self-reported outcome measures (OKS and FJS). A mean OKS score of 37.71 (± 9.23) and a mean FJS score of 63.65 (± 31.01) could be obtained. CONCLUSION: This large clinical study suggests that constrained devices provide the best results when treating bone-on-bone tricompartimental osteoarthritis of the knee with severe axial deviation (valgus/varus > 15°) and/or persistent ligamentous instability.