Magnetic resonance imaging diagnosis of subependymal giant cell astrocytomas in follow-up of children with tuberous sclerosis complex: should we always use contrast enhancement?

BACKGROUND: Subependymal giant cell astrocytomas (SEGAs) arise in 10-26% of tuberous sclerosis complex (TSC) patients. SEGAs cause obstructive hydrocephalus and increase morbi-mortality. It is recommended that TSC patients be followed with contrast enhanced magnetic resonance imaging (CE-MRI), but repetitive use of gadolinium-based contrast-agents (GBCAs) may cause organ deposits. OBJECTIVE: To compare the diagnostic performances of non-CE- and CE-MRI to differentiate SEGAs from subependymal nodules in TSC patients during follow-up. MATERIALS AND METHODS: Thirty-five TSC patients (median age: 2.4 years) were enrolled in this retrospective single-center study from September 2007 to January 2019. Inclusion criteria were a certain diagnosis of TSC and at least three follow-up brain MRIs with GBCA injection. Two consecutive MRI scans per patient were selected and anonymized. Three radiologists performed a blinded review of non-enhanced and enhanced MRI sequences during different sessions. The diagnostic performances were compared (sensitivity, specificity, positive/negative predictive values, accuracy, inter/intra-observer agreements). RESULTS: The accuracies for detecting SEGAs were good and similar between the non-enhanced and enhanced MRI sequences. The sensitivity and specificity of non-CE-MRI to diagnose SEGA ranged from 75% to 100% and from 94% to 100%, respectively. The differences in numbers of false-positive and false-negative patients between non-CE- and CE-MRI never exceeded one case. Nodules size >10 mm, location near the Monro foramen, hydrocephalus and modifications between two consecutive MRI scans were significantly associated with the diagnosis of SEGA for the three readers (all P-values <0.05). Inter- and intra-observer agreements were also excellent for non-enhanced and enhanced MRI sequences (kappa=0.85-1 and 0.81-0.93, respectively). CONCLUSION: The performances of non-enhanced and enhanced MRI sequences are comparable for detecting SEGAs, questioning the need for systematic GBCA injections for TSC patients.

Percutaneous cryoablation of symptomatic localized venous malformations: preliminary short-term results.

Short-term outcomes after percutaneous image-guided cryoablation of symptomatic venous malformations in four consecutive patients (mean age, 42.5 y) are reported. Two patients had local recurrences after previous treatment. Mean preoperative pain was estimated on a visual analog scale at 5 (range, 3-7). Cryoablation was performed in a single session under general anesthesia. Postoperative pain and superficial edema disappeared within 2 weeks. No pain was subsequently reported, and magnetic resonance imaging demonstrated a significant volume decrease at 3 months (75%; P = .01) and at 6 months (95%; P = .01). Percutaneous cryoablation shows promising local control in patients with symptomatic venous malformations.

Salvage CT-guided transgluteal cryoablation for locally recurrent prostate cancer: initial experiences.

Technical feasibility of a computed tomography (CT)-guided transgluteal approach for salvage cryoablation of inoperable locally recurrent prostate cancer was evaluated retrospectively. Five procedures were performed under general anesthesia in five patients previously treated with radiation therapy. Median age was 64 years, and average pretreatment prostate-specific antigen (PSA) level was 2.77 ng/dL (range, 0.56-4.23 ng/dL). Each cryoablation procedure was completed in one session. No complications were reported. Mean 3-month and 6-month PSA levels were 0.35 ng/dL (range, 0.16-0.54 ng/dL) and 0.51 ng/dL (range, 0.09-0.94 ng/dL), respectively, representing mean decreases of 84% (range, 71%-92%) and 81% (range, 78%-84%), respectively. Salvage CT-guided transgluteal cryoablation of the prostate therefore appears technically feasible.

Intracranial empyema complicating sinusitis in childhood: Epidemiology, imaging findings and outcome.

BACKGROUND: To describe clinical presentations of intracranial sinusitis complications in childhood, their pitfalls and imaging findings. MATERIEL AND METHODS: This retrospective IRB-approved single-center study included infants diagnosed with sinusitis and empyema and/or other intracranial complications who underwent imaging between September 2008 and September 2019. Three radiologists individually reviewed clinical charts and imaging findings, including sinusitis complications and at-risk anatomical variations. RESULTS: 21 children (76% males and 24% females, mean age 13±3.1 years) with imaging pansinusitis were included. Headache (95%) and fever (90%) were the main clinical nonspecific signs. Ten (48%) children presented an extradural empyema, nine (43%) children had a subdural empyema and two (10%) children had both. Frontal location sinusitis was the most common (76%). In MRI, all empyema presented as a hypo intensity on pre-contrast T1-WI, a hyperintensity on T2-WI, a reduced apparent diffusion coefficient (ADC) on diffusion weighted imaging (DWI) and a peripheral contrast enhancement on post-contrast T1-WI. CT or MRI revealed intracranial complications such as a collection size increase (52%), a midline shift (62%), intraparenchymal abscesses (24%), a cerebral venous thrombosis (29%), an intracranial pressure increase (29%), cerebral ischemia (43%) and Pott's Puffy Tumor (10%). Imaging highlighted sinus anatomical abnormalities in 52% of cases. All children were treated with sinus drainage and/or neurosurgery. Long-term follow-up was favorable in 14 cases (67%). CONCLUSION: Complications of sinusitis are life threatening in the studied population. Empyema and cerebral complications may be misleading. Brain contrast-enhanced CT covering sinuses and orbits, is mainly the first examination done but MRI is mandatory.