Craniopharyngioma

Craniopharyngiomas are rare malformational tumours of low histological malignancy arising along the craniopharyngeal duct. The two histological subtypes, adamantinomatous craniopharyngioma (ACP) and papillary craniopharyngioma (PCP), differ in genesis and age distribution. ACPs are diagnosed with a bimodal peak of incidence (5-15 years and 45-60 years), whereas PCPs are restricted to adults mainly in the fifth and sixth decades of life. ACPs are driven by somatic mutations in CTNNB1 (encoding β-catenin) that affect β-catenin stability and are predominantly cystic in appearance. PCPs frequently harbour somatic BRAFV600E mutations and are typically solid tumours. Clinical manifestations due to increased intracranial pressure, visual impairment and endocrine deficiencies should prompt imaging investigations, preferentially MRI. Treatment comprises neurosurgery and radiotherapy; intracystic chemotherapy is used in monocystic ACP. Although long-term survival is high, quality of life and neuropsychological function are frequently impaired due to the close anatomical proximity to the optic chiasm, hypothalamus and pituitary gland. Indeed, hypothalamic involvement and treatment-related hypothalamic lesions frequently result in hypothalamic obesity, physical fatigue and psychosocial deficits. Given the rarity of these tumours, efforts to optimize infrastructure and international collaboration should be research priorities

Electron spin coherence in metallofullerenes: Y, Sc and La@C82

Endohedral fullerenes encapsulating a spin-active atom or ion within a carbon cage offer a route to self-assembled arrays such as spin chains. In the case of metallofullerenes the charge transfer between the atom and the fullerene cage has been thought to limit the electron spin phase coherence time (T2) to the order of a few microseconds. We study electron spin relaxation in several species of metallofullerene as a function of temperature and solvent environment, yielding a maximum T2 in deuterated o-terphenyl greater than 200 microseconds for Y, Sc and La@C82. The mechanisms governing relaxation (T1, T2) arise from metal-cage vibrational modes, spin-orbit coupling and the nuclear spin environment. The T2 times are over 2 orders of magnitude longer than previously reported and consequently make metallofullerenes of interest in areas such as spin-labelling, spintronics and quantum computing.Comment: 5 pages, 4 figure

Fully automatic algorithm for detecting and tracking anatomical shoulder landmarks on fluoroscopy images with artificial intelligence.

OBJECTIVE Patients with rotator cuff tears present often with glenohumeral joint instability. Assessing anatomic angles and shoulder kinematics from fluoroscopy requires labelling of specific landmarks in each image. This study aimed to develop an artificial intelligence model for automatic landmark detection from fluoroscopic images for motion tracking of the scapula and humeral head. MATERIALS AND METHODS Fluoroscopic images were acquired for both shoulders of 25 participants (N = 12 patients with unilateral rotator cuff tear, 6 men, mean (standard deviation) age: 63.7 ± 9.7 years; 13 asymptomatic subjects, 7 men, 58.2 ± 8.9 years) during a 30° arm abduction and adduction movement in the scapular plane with and without handheld weights of 2 and 4 kg. A 3D full-resolution convolutional neural network (nnU-Net) was trained to automatically locate five landmarks (glenohumeral joint centre, humeral shaft, inferior and superior edges of the glenoid and most lateral point of the acromion) and a calibration sphere. RESULTS The nnU-Net was trained with ground-truth data from 6021 fluoroscopic images of 40 shoulders and tested with 1925 fluoroscopic images of 10 shoulders. The automatic landmark detection algorithm achieved an accuracy above inter-rater variability and slightly below intra-rater variability. All landmarks and the calibration sphere were located within 1.5 mm, except the humeral landmark within 9.6 mm, but differences in abduction angles were within 1°. CONCLUSION The proposed algorithm detects the desired landmarks on fluoroscopic images with sufficient accuracy and can therefore be applied to automatically assess shoulder motion, scapular rotation or glenohumeral translation in the scapular plane. CLINICAL RELEVANCE STATEMENT This nnU-net algorithm facilitates efficient and objective identification and tracking of anatomical landmarks on fluoroscopic images necessary for measuring clinically relevant anatomical configuration (e.g. critical shoulder angle) and enables investigation of dynamic glenohumeral joint stability in pathological shoulders. KEY POINTS • Anatomical configuration and glenohumeral joint stability are often a concern after rotator cuff tears. • Artificial intelligence applied to fluoroscopic images helps to identify and track anatomical landmarks during dynamic movements. • The developed automatic landmark detection algorithm optimised the labelling procedures and is suitable for clinical application

Posterior hypothalamus-sparing surgery improves outcome after childhood craniopharyngioma

Objective: Quality of life (QoL) is frequently impaired in childhood-onset craniopharyngioma (CP) by hypothalamic syndrome. The debate, whether pretreatment hypothalamic involvement (HI) has apriori prognostic impact or surgical hypothalamic lesions (HL) determine outcome, is controversial. Design: Survival and outcome of CPs recruited between 2007 and 2014 in KRANIOPHARYNGEOM 2007 were analyzed with regard to reference-confirmed presurgical HI and surgical HL. Methods: Radiological findings, BMI and QoL were assessed at diagnosis and during follow-up. QoL was assessed using Pediatric Quality of Life (PEDQOL) questionnaire. Results: One hundred sixty-nine CPs were included presenting with no HI (n = 11), anterior (n = 49) and anterior + posterior (a + p) HI (n = 109) prior to surgery. The latter 109 were analyzed for postoperative HL (no lesion: n = 23, anterior HL: n = 29, a + pHL: n = 57). Progression-free survival (PFS) was higher after complete resection. The highest PFS was observed in CP with a + pHL, especially when compared between non-irradiated subgroups (P = 0.006). Overall survival (OS) rates were 1.0 in all subgroups. CP with a + pHL developed higher BMI (P ≤ 0.001) during follow-up compared between subgroups. 55/109 pts with a + pHI completed PEDQOL at diagnosis (48/109 at 3 years follow-up). QoL was worse for a + pHL patients in terms of physical, social and emotional functionality when compared with the anterior HL and no HL subgroup. BMI development and QoL during follow-up were similar for patients with anterior HL and without HL. Conclusions: Posterior hypothalamus-sparing surgical strategies are associated with higher QoL, decreased development of obesity and lower PFS in CP