Automated MRI perfusion-diffusion mismatch estimation may be significantly different in individual patients when using different software packages.

OBJECTIVE: To compare two established software applications in terms of apparent diffusion coefficient (ADC) lesion volumes, volume of critically hypoperfused brain tissue, and calculated volumes of perfusion-diffusion mismatch in brain MRI of patients with acute ischemic stroke. METHODS: Brain MRI examinations of 81 patients with acute stroke due to large vessel occlusion of the anterior circulation were analyzed. The volume of hypoperfused brain tissue, ADC volume, and the volume of perfusion-diffusion mismatch were calculated automatically with two different software packages. The calculated parameters were compared quantitatively using formal statistics. RESULTS: Significant difference was found for the volume of hypoperfused tissue (median 91.0 ml vs. 102.2 ml; p < 0.05) and the ADC volume (median 30.0 ml vs. 23.9 ml; p < 0.05) between different software packages. The volume of the perfusion-diffusion mismatch differed significantly (median 47.0 ml vs. 67.2 ml; p < 0.05). Evaluation of the results on a single-subject basis revealed a mean absolute difference of 20.5 ml for hypoperfused tissue, 10.8 ml for ADC volumes, and 27.6 ml for mismatch volumes, respectively. Application of the DEFUSE 3 threshold of 70 ml infarction core would have resulted in dissenting treatment decisions in 6/81 (7.4%) patients. CONCLUSION: Volume segmentation in different software products may lead to significantly different results in the individual patient and may thus seriously influence the decision for or against mechanical thrombectomy. KEY POINTS: • Automated calculation of MRI perfusion-diffusion mismatch helps clinicians to apply inclusion and exclusion criteria derived from randomized trials. • Infarct volume segmentation plays a crucial role and lead to significantly different result for different computer programs. • Perfusion-diffusion mismatch estimation from different computer programs may influence the decision for or against mechanical thrombectomy.

Large, segmental, circular vascular malformation of the small intestine (in a female toddler with hematochezia): unusual presentation in a child.

BACKGROUND: Failure to thrive and hematochezia in children may be alarm signs warranting endoscopy. In contrast, vascular malformations of the small intestine are uncommon in this age group. We report on a female toddler in whom various imaging techniques revealed an unusually large segmental vascular malformation of the ileum as the cause of the child's main clinical symptoms. CASE PRESENTATION: A 19 months old girl presented with severe anemia (Hb 3 mmol/l), failure to thrive and chronic diarrhea. Diagnostics for intestinal blood loss and pathogens were negative. The child had duodenoscopy, also for histological diagnosis of celiac disease, with negative results. A dietary protocol was suggestive for inadequate iron intake and she was supplemented. After symptomless four-months the child presented again, now with mild abdominal pain and, for the first time, hematochezia. An orienting abdominal ultrasound (US) study showed a suspicious tumorous bowel condition. A subsequent detailed abdominal US supplemented by a saline enema during investigation (i.e., "hydrocolon", to improve outlining of the formation's localization) revealed a large circumferential cystiform vascular mass of the ileum causing segmental ileal obstruction.Complementing preoperative abdominal hydro-MRI, planned based on the findings of the US study, confirmed the suspected vascular malformation of the ileum and exquisitely outlined the extent, location and anatomy.The patient was successfully operated laparoscopically, the affected ileum segment with the mass was completely removed as proven by histology, and the child recovered well. CONCLUSIONS: The huge segmental vascular malformation of the distal ileum described here is an extreme rarity in young children. Although the reported child's presenting symptoms malabsorption and malnutrition could have been responsible for its severe anemia, this was obviously caused by blood losses from the ileal vascular malformation. It was due to incipient abdominal pain rather than hematochezia that abdominal US was performed and proved crucial for correctly diagnosing this rare malformation. Even in this extensive case detailed imaging work-up including adapted MRI added all information necessary for minimal invasive laparoscopic en bloc resection.

Cardiac movement identified on prehospital echocardiography predicts outcome in cardiac arrest patients.

INTRODUCTION: The prognostic value of emergency echocardiography (EE) in the management of cardiac arrest patients has previously been studied in an in-hospital setting. These studies mainly included patients who underwent cardiopulmonary resuscitation (CPR) by emergency medicine technicians at the scene and who arrived at the emergency department (ED) still in a state of cardiac arrest. In most European countries, cardiac arrest patients are normally treated by physician-staffed emergency medical services (EMS) teams on scene. Transportation to the ED while undergoing CPR is uncommon. OBJECTIVE: To evaluate the ability of EE to predict outcome in cardiac arrest patients when it is performed by ultrasound-inexperienced emergency physicians on scene. METHODS: We performed a prospective, observational study of nonconsecutive, nontrauma, adult cardiac arrest patients who were treated by physician-staffed urban EMS teams on scene. Participating emergency physicians (EPs) received a two-hour course in EE during CPR. After initial procedures were accomplished, EE was performed during a rhythm and pulse check. A single subxiphoid, four-chamber view was required for study enrollment. We defined sonographic evidence of cardiac kinetic activity as any detected motion of the myocardium, ranging from visible ventricular fibrillation to coordinated ventricular contractions. The CPR had to be continued for at least 15 minutes after the initial echocardiography. No clinical decisions were made based on the results of EE. RESULTS: Forty-two patients were enrolled in the study. The heart could be visualized successfully in all patients. Five (11.9%) patients survived to hospital admission. Of the 32 patients who had cardiac standstill on initial EE, only one (3.1%) survived to hospital admission, whereas four out of 10 (40%) patients with cardiac movement on initial EE survived to hospital admission (p = 0.008). Neither asystole on initial electrocardiogram nor peak capnography value, age, bystander CPR, or downtime was a significant predictor of survival. Only cardiac movement was associated with survival, and cardiac standstill at any time during CPR resulted in a positive predictive value of 97.1% for death at the scene. CONCLUSION: Our results support the idea of focused echocardiography as an additional criterion in the evaluation of outcome in CPR patients and demonstrate its feasibility in the prehospital setting.

Computed Tomography Angiography (CTA) in Selected Scenarios with Risk of Possible False-Positive or False-Negative Conclusions in Diagnosing Brain Death.

It is widely accepted that brain death (BD) is a diagnosis based on clinical examination. However, false-positive and false-negative evaluation results may be serious limitations. Ancillary tests are used when there is uncertainty about the reliability of the neurologic examination. Computed tomography angiography (CTA) is an ancillary test that tends to have the lowest false-positive rates. However, there are various influencing factors that can have an unfavorable effect on the validity of the examination method. There are inconsistent protocols regarding the evaluation criteria such as scoring systems. Among the most widely used different scoring systems the 4-point CTA-scoring system has been accepted as the most reliable method. Appropriate timing and/or Doppler pre-testing could reduce the number of possible premature examinations and increase the sensitivity of CTA in diagnosing cerebral circulatory arrest (CCA). In some cases of inconclusive CTA, the whole brain computed tomography perfusion (CTP) could be a crucial adjunct. Due to the increasing significance of CTA/CTP in determining BD, the methodology (including benefits and limitations) should also be conveyed via innovative electronic training tools, such as the BRAINDEXweb teaching tool based on an expert system.

Relationship between stroke etiology and collateral status in anterior circulation large vessel occlusion.

BACKGROUND AND PURPOSE: Clinical outcome after mechanical thrombectomy (MT) for large vessel occlusion (LVO) stroke is influenced by the intracerebral collateral status. We tested the hypothesis that patients with preexisting ipsilateral extracranial carotid artery stenosis (CAS) would have a better collateral status compared to non-CAS patients. Additionally, we evaluated MT-related adverse events and outcome for both groups. METHODS: Over a 7-year period, we identified all consecutive anterior circulation MT patients (excluding extracranial carotid artery occlusion and dissection). Patients were grouped into those with CAS ≥ 50% according to the NASCET criteria and those without significant carotid stenosis (non-CAS). Collateral status was rated on pre-treatment CT- or MR-angiography according to the Tan Score. Furthermore, we assessed postinterventional infarct size, adverse events and functional outcome at 90 days. RESULTS: We studied 281 LVO stroke patients, comprising 46 (16.4%) with underlying CAS ≥ 50%. Compared to non-CAS stroke patients (n = 235), patients with CAS-related stroke more often had favorable collaterals (76.1% vs. 46.0%). Recanalization rates were comparable between both groups. LVO stroke patients with underlying CAS more frequently had adverse events after MT (19.6% vs. 6.4%). Preexisting CAS was an independent predictor for favorable collateral status in multivariable models (Odds ratio: 3.3, p = 0.002), but post-interventional infarct size and functional 90-day outcome were not different between CAS and non-CAS patients. CONCLUSIONS: Preexisting CAS ≥ 50% was associated with better collateral status in LVO stroke patients. However, functional 90-day outcome was independent from CAS, which could be related to a higher rate of adverse events.

Downgrading of a G3 Neuroendocrine Tumor to a G2 Tumor: Can First-Line Cytotoxic Chemotherapy Change the Tumor Biology?

The antiproliferative treatment options for neuroendocrine tumors (NET)/neuroendocrine carcinomas of the gastrointestinal tract critically depend on the proliferation rate, evaluated by immunohistochemical staining for Ki-67. According to their grading, tumors are treated with somatostatin analogs, mTOR inhibitors, or cytotoxic substances. This case illustrates downgrading of a primarily highly proliferative NET achieved by a variation of cytotoxic chemotherapy regimens, followed by a combination therapy using everolimus together with lanreotide. The latter medication might lead to a good clinical response as far as tumor growth is concerned.

Congenital hearing loss explained in adulthood. Computed tomography of the temporal bone in hemifacial microsomia. A case report.

We present a case of complex hemifacial microsomia (HFM) which was diagnosed at the age of 46 years. Imaging findings of a complex deformity of the temporal bone are presented and connected to a broad range of clinical symptoms. Computed tomography (CT) imaging indications are discussed briefly.