Validation of the standardization framework SSTR-RADS 1.0 for neuroendocrine tumors using the novel SSTR­targeting peptide [18F]SiTATE.

OBJECTIVES: Somatostatin receptor positron emission tomography/computed tomography (SSTR-PET/CT) using [68Ga]-labeled tracers is a widely used imaging modality for neuroendocrine tumors (NET). Recently, [18F]SiTATE, a SiFAlin tagged [Tyr3]-octreotate (TATE) PET tracer, has shown great potential due to favorable clinical characteristics. We aimed to evaluate the reproducibility of Somatostatin Receptor-Reporting and Data System 1.0 (SSTR-RADS 1.0) for structured interpretation and treatment planning of NET using [18F]SiTATE. METHODS: Four readers assessed [18F]SiTATE-PET/CT of 95 patients according to the SSTR-RADS 1.0 criteria at two different time points. Each reader evaluated up to five target lesions per scan. The overall scan score and the decision on peptide receptor radionuclide therapy (PRRT) were considered. Inter- and intra-reader agreement was determined using the intraclass correlation coefficient (ICC). RESULTS: The ICC analysis on the inter-reader agreement using SSTR-RADS 1.0 for identical target lesions (ICC ≥ 85%), overall scan score (ICC ≥ 90%), and the decision to recommend PRRT (ICC ≥ 85%) showed excellent agreement. However, significant differences were observed in recommending PRRT among experienced readers (ER) (p = 0.020) and inexperienced readers (IR) (p = 0.004). Compartment-based analysis demonstrated good to excellent inter-reader agreement for most organs (ICC ≥ 74%), except for lymph nodes (ICC ≥ 53%). CONCLUSION: SSTR-RADS 1.0 represents a highly reproducible and consistent framework system for stratifying SSTR-targeted PET/CT scans, even using the novel SSTR-ligand [18F]SiTATE. Some inter-reader variability was observed regarding the evaluation of uptake intensity prior to PRRT as well as compartment scoring of lymph nodes, indicating that those categories require special attention during further clinical validation and might be refined in a future SSTR-RADS version 1.1. CLINICAL RELEVANCE STATEMENT: SSTR-RADS 1.0 is a consistent framework for categorizing somatostatin receptor-targeted PET/CT scans when using [18F]SiTATE. The framework serves as a valuable tool for facilitating and improving the management of patients with NET. KEY POINTS: SSTR-RADS 1.0 is a valuable tool for managing patients with NET. SSTR-RADS 1.0 categorizes patients with showing strong agreement across diverse reader expertise. As an alternative to [68Ga]-labeled PET/CT in neuroendocrine tumor imaging, SSTR-RADS 1.0 reliably classifies [18F]SiTATE-PET/CT.

Quantitative evaluation of metamorphopsia with M-CHARTS™ and evaluation of retinal morphologic changes by optical coherence tomography before and after pars plana vitrectomy in patients with idiopathic epiretinal membrane.

PURPOSE: We aimed to quantitatively evaluate metamorphopsia pre- and postoperatively in patients with idiopathic epiretinal membrane(iERM) using M-CHARTS™ and to evaluate the relationship between morphological changes in retinal layers on optical coherence tomography (OCT) and metamorphopsia scores. MATERIALS AND METHODS: This prospective study included 42 patients followed in Akdeniz University Hospital Ophthalmology Clinic diagnosed with iERM by fundus examination and OCT between 2020-2022. Detailed ophthalmologic findings, visual acuities, metamorphopsia scores, and OCT parameters of all patients were recorded. The relationship between pre- and postoperative visual acuity, metamorphopsia scores and OCT parameters was investigated. Changes in OCT parameters were compared by evaluating patients with stable or increasing metamorphopsia scores as one group (group1) and patients with decreasing metamorphopsia scores as the other group (group 2). RESULTS: In "group 2", preoperative Ganglion Cell Layer+Inner Plexiform Layer (Central) (GCL+IPL (C)) was significantly (P: 0.028) higher than in "group 1". CONCLUSION: A statistically significant preoperative thickness difference in the OCT parameters of the GCL+IPL (C) layer was associated with the quantitative metamorphopsia complaints of the patients. The thickness of the preoperative GCL+IPL (C) layer can be considered an important indicator of symptoms of metamorphopsia determining functional success after surgery.

Propensity Score Analysis of Flow Diverters Placed in Scaffolding Stents.

BACKGROUND AND PURPOSE: Flow-diverter deployment within a stent remains controversial, but flow-diverter deployment within a scaffolding stent has been performed occasionally. To date, an analysis of this scaffolding technique has not been reported. We aimed to evaluate whether the scaffolding technique adversely affects the outcomes of flow diversion. MATERIALS AND METHODS: Patients who had undergone intracranial aneurysm treatment using a Silk flow diverter with (scaffolding group) or without (bare flow-diverter group) a scaffolding stent were identified retrospectively and compared. Propensity score matching was used to match the aneurysms in both groups for variables with a significant difference between groups. Aneurysm occlusion rates and clinical outcomes were compared. RESULTS: There were 84 patients (105 aneurysms) in the bare flow-diverter group and 21 patients (22 aneurysms) in the scaffolding group (using 20 LEO stents and 1 Enterprise stent). The aneurysms in the scaffolding group were larger (mean, 13.1 [SD, 10.7] versus 7 [SD, 4.5] mm, P = .001) and more likely to be fusiform (40.9% versus 5.7%, P < .001) than in the bare flow-diverter group. After 2:1 propensity score matching, 24 aneurysms in the bare flow-diverter group and 15 in the scaffolding group were matched. Aneurysm occlusion rates did not significantly differ between groups at 1-3 months (41.2 versus 33.3%, P > .99), 3-6 months (55.5 versus 75.0%, P = .44), 7-12 months (65.0 versus 90.0%, P = .21), or beyond 1 year (73.6 versus 91.6%, P = .36). There was no difference in complication rates between the groups (P > .99). CONCLUSIONS: Placement of a scaffolding stent before flow diversion does not adversely affect aneurysm occlusion or complication rates.

Placement of a Stent within a Flow Diverter Improves Aneurysm Occlusion Rates.

BACKGROUND AND PURPOSE: Placement of a stent within a flow diverter has been described previously but its consequences have not been analyzed. We evaluated the clinical and angiographic results of stent placement within a flow diverter during the same treatment session. MATERIALS AND METHODS: All patients treated with a Surpass flow diverter were retrospectively evaluated. Patients with previously deployed stents and procedures in which scaffolding stents, a second flow diverter, or intrasaccular devices were used were excluded. Patient and aneurysm characteristics and clinical and imaging follow-up results were compared between stented and nonstented Surpass flow-diverter groups and stent assisted coiling. RESULTS: Thirty-five patients (41 aneurysms) were treated with a Surpass flow diverter only (monotherapy group), and in 33 patients (35 aneurysms), a stent was placed within the Surpass flow diverter (stented group). Stents were placed inside the Surpass flow diverter for a variety of reasons at the operator's discretion. No statistical difference was noted between the 2 groups in age, body weight, sex, history of thromboembolic events, smoking, platelet inhibition levels, hypertension, hyperlipidemia, diabetes mellitus, malignancy, and aneurysm location. Aneurysms in the stented group were larger than those in the monotherapy group (14.8 versus 9.1 mm, P < .001). The rate of clinically significant adverse events and complete aneurysm occlusion rates at 0-3 and 3-6 months (73.3% versus 61.3%, P = .31, and 84.8% versus 70.2%, P = .14) were similar. At 9-12 months, a significantly higher proportion of aneurysms in the stented group achieved complete occlusion (93.9% versus 73.2%, P = .019). There was a trend toward a higher obliteration rate on final follow-up in the stented group (93.9% versus 82.9%, P = .14). CONCLUSIONS: Placement of a stent within a flow diverter increases the rate of aneurysm occlusion. We propose that these results are from improved flow-diverter apposition due to the higher radial force of intracranial stents.

Neurothekeoma in the middle cranial fossa as a rare location: Case report and literature review.

Neurothekeoma is a benign cutaneous nerve sheath tumor usually located in the head and neck region. To date, only a few cases of intracranial location have been reported in the literature. We report an extremely rare case of intracranial neurothekeoma located in the brain parenchyma of the middle cranial fossa. A 55-year-old female patient was operated on at our clinic for a right temporal cystic mass lesion with heterogenic contrast enhancement. Histologically, the tumor had a multinodular hypercellular appearance with a myxoid matrix, peripheral fibrosis, and sclerosis. It was characterized by spindle and epithelioid mononuclear cells, immunochemically positive with diffuse S-100, vimentin, GFAP, PGP 9.5, and NSE, as characteristics of cellular neurothekeomas. After a total surgical resection, there was no need for further adjuvant chemotherapy or radiotherapy. Because there were still unclear aspects regarding the origin, pathogenesis and management of the intracranial neurothekeomas, we decided to contribute to the literature with this case report.