Intra-arterial chemotherapy for retinoblastoma: the dosimetric impact.

PURPOSE: Purposes are (1) to measure main radiation parameters and (2) to propose a method to estimate the absorbed doses of internal organs starting from DAP values. Measuring the exposition of internal organs by repeated irradiations on an anthropomorphic phantom with the same settings used in vivo, we could establish correlations between (1) DAP and the dose recorded by a dosimeter placed along the X-ray beam entrance pathway; (2) the dose recorded by the same dosimeter and the absorbed dose in internal organs. METHODS: Forty-four consecutive patients (16 males, 28 females) (mean age 35.4 months) treated at our institution with IAC (216 procedures: 196 via the ICA and 20 into branches of the ECA) were included in this prospective study. IAC was divided into 5 phases. Fluoroscopic time, DAP, and ESD were measured. RESULTS: The mean DAP was 595 ± 445 cGy cm2 and the mean fluoroscopic time was 540 ± 403 s. ESD was on average 9.59 mGy (range 0.8-165 mGy). The absorbed dose was lower than 12.1 mGy in the left retina (the more exposed organ) in 75% of single treatments and lower than 25 mGy in 95% of treatments. In the cases of 3 and 6 sessions, the left retina of 75% of patients absorbed respectively less than 36.3 and 72.7 mGy, whereas the left retina of 95% of patients received less than 75.2 and 150.4 mGy. Other organs were less exposed. CONCLUSION: This paper describes a method of absorbed dose estimation providing ranges used clinically in a single practice and the basis for further prospective studies.

Single-center experience using the 3MAX or 4MAX reperfusion catheter for the treatment of acute ischemic stroke with distal arterial occlusions in patients not eligible for intravenous fibrinolysis.

BACKGROUND: In acute stroke, distal cerebrovascular occlusions can be linked to severe clinical symptoms, and treatment by mechanical thrombectomy may have an important clinical impact. When intravenous fibrinolytic therapy is firmly contraindicated, it remains the only treatment option. METHODS: A total of 42 patients with isolated distal arterial occlusions and absolute contraindication for intravenous fibrinolytic therapy were retrospectively included. Mechanical thrombectomy was performed using Penumbra 4MAX or 3MAX aspiration catheters. When aspiration alone did not result in successful revascularization, a stent retriever was added. RESULTS: Direct thromboaspiration was the first treatment option in all patients. 16.7% of cases required the additional use of a stent retriever. A TICI score ≥ 2b reperfusion at the end of the procedure was obtained in 76.2% and a Rankin Score of 2 or less at 90 days in 45.7%. Two hemorrhagic complications were observed. CONCLUSIONS: Direct thromboaspiration appears a safe technique in acute isolated distal arterial occlusions. In a cohort of patients with absolute contraindication for intravenous fibrinolytic therapy, a significant percentage achieved good revascularization.

Transorbital anastomotic pathways between the external and internal carotid systems in children affected by intraocular retinoblastoma.

PURPOSE: It is well known that many anastomoses can join the external carotid system and the ophthalmic artery. However, their frequency has never been reported. Since they can be relevant for interventional radiologists operating in the orbit, we decided to illustrate and determine the frequency of the anastomoses that can be found in children. METHODS: A retrospective study of 443 angiographic procedures (via ophthalmic artery and/or external carotid artery) carried out on 97 children affected by intraocular retinoblastoma was made to investigate the arterial anatomy of 106 orbits. RESULTS: Anastomoses were observed in 44.33 % of orbits. However, their true frequency is likely much higher as the rate of visualization increased up to 91.11 % of orbits when the angiographic study was extended to the external carotid artery. In order of frequency we detected the following anastomoses: lacrimal artery-middle meningeal artery, lacrimal artery-anterior deep temporal artery, ophthalmic artery-middle meningeal artery, ophthalmic artery-facial artery, supraorbital artery-superficial temporal artery, supratrochlear artery-superficial temporal artery, supraorbital artery-middle meningeal artery, dorsal nasal artery-infraorbital artery, supraorbital artery-zygomaticoorbital artery, lacrimal artery-zygomaticoorbital artery. CONCLUSION: When properly searched, anastomoses between the ophthalmic artery and the external carotid artery are almost constant in children. Depending on the clinical scenario, they can represent dangers or valuable alternative routes for collateral circulations and intraarterial chemotherapy.

Identification of Intraorbital Arteries in Pediatric Age by High Resolution Superselective Angiography.

PURPOSE: Angiography is a powerful tool to identify intraorbital arteries. However, the incidence by which these vessels can be identified is unknown. Our purpose was to determine such incidence and which angiographic approach is best for the identification of each artery. METHODS: A retrospective study of 353 angiographic procedures (via ophthalmic artery and/or external carotid artery) carried out on 79 children affected by intraocular retinoblastoma was made to investigate the arterial anatomy in 87 orbits. For each intraorbital artery two parameters were calculated: the angiographic incidence, as the percentage of times a given artery was identified, and the visibility index, as the ratio between the angiographic incidence and the true anatomic incidence. RESULTS: All collaterals of the ophthalmic artery could be spotted. Most of them were identified with a high angiographic incidence; some of them were less easily identified because too thin or because frequently shielded. The visibility index paralleled the angiographic incidence of most arteries. However, the lacrimal and meningolacrimal arteries had a higher visibility index suggesting that their identification was more frequent than the angiographic incidence alone could suggest. Statistical analysis demonstrated that the lacrimal artery and some muscular branches had higher chances to be identified if the angiography of the ophthalmic artery was accompanied by the study of the external carotid system. CONCLUSION: This work provides an objective measure of how powerful angiography is to identify intraorbital arteries as well as useful references for professionals who need to operate in the orbit.

Pseudo-intraventricular hemorrhage from a deep calcarine fissure.

Evidence of areas of increased attenuation density within lateral ventricles at computed tomography (CT) of the brain is a finding of acute or subacute intraventricular hemorrhage. The purpose of this case report is to describe a 14-year-old female who presented with an episode of complicated migraine. Brain CT showed an area of high attenuation density (35 Hounsfield Units) in the trigone and occipital horn of the right lateral ventricle, mimicking a blood-fluid level from subacute intraventricular hemorrhage. Magnetic resonance imaging (MRI) of the brain showed that this resulted from gray matter lining a deep calcarine fissure. A deep calcarine fissure may mimic intraventricular hemorrhage at CT. Correct CT and MRI interpretation allows to avoid invasive diagnostic tests including lumbar puncture or intra-arterial catheter angiography.

Subcortical low-intensity and restricted diffusion after first seizure in a child.

Our purpose was to increase the knowledge about subcortical low-intensity images on long repetition time by describing brain magnetic resonance images of a young boy after his first spontaneous seizure. Evident in the epileptogenic area were transient images of reversible subcortical low intensity on long-repetition time, T2*-weighted, and b = 0 s/mm2 diffusion, isointense signal on b = 1000 s/mm2 diffusion, and restricted diffusion. Most likely, mechanism was axonal flow disruption with iron accumulation and free radicals production induced during seizure.

Pyogenic abscess from Providencia stuartii mimicking necrotic tumour at perfusion-weighted imaging.

The purpose of this case report is to increase the knowledge about magnetic resonance spectrum of pyogenic abscesses of the brain. A 74-year-old woman presented with a left frontal lobe cystic mass, developed in the site of post-traumatic contusions after surgical evacuation of a subdural hematoma. MR imaging showed an ipsilateral mass lesion with a thin, regular rim of T1 high-intensity signal, T2 low-intensity signal, and gadolinium-enhancement. Diffusion-weighted imaging with measure of apparent diffusion coefficient value showed inhomogenous diffusion restriction in the lesion core. Perfusion-weighted imaging (PWI) demonstrated high relative cerebral blood volume (rCBV) in both the lesion wall and perilesional area, with a maximal rCBV ratio (rCBV of the lesion/rCBV of the normal contralateral white matter) of 5.65 and 0.58, respectively. As a result, surgery and pathology showed a pyogenic abscess. Cultures grew were Providencia stuartii species. In conclusion, a pyogenic brain abscess from P. stuartii may show high rCBV at PWI, thus mimicking a necrotic tumour.

Arterial Spin Labeling Magnetic Resonance Imaging to Diagnose Contrast-Induced Vasospasm After Intracranial Stent Embolization.

BACKGROUND: Contrast-induced encephalopathy (CIE) is a rare and misdiagnosed complication of intravascular injection of contrast, responsible for arterial vasospasm and neurologic effects. Conventional radiologic findings are not in themselves specific for cerebral vasospasm diagnosis. We present a case in which arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) was useful in early diagnosis of CIE. CASE DESCRIPTION: A 56-year-old woman was admitted for elective flow-diverter embolization of a recanalized left supra-ophthalmic internal carotid artery aneurysm; at 4 hours postprocedure, she acutely developed sensitive aphasia and right arm paresis. Although no-contrast computed tomography and MRI with fluid-attenuated inversion recovery and diffusion-weighted imaging sequences did not demonstrate acute ischemic/hemorrhagic cerebral foci or cortical edema, ASL showed decreased cerebral blood flow (CBF) in the insular-temporal-parietal anterior lobe, suspected for hypoperfusion due to vasospasm, which was not confirmed by subsequent emergent digital subtraction angiography. At 16 hours, because of worsening symptoms, patient underwent an additional MRI, which showed slight insular cortical edema on fluid-attenuated inversion recovery and corresponding slight restricted diffusion-weighted imaging with a severe reduction in CBF value; at this time, emergent digital subtraction angiography demonstrated distal arterial vasospasm of left middle cerebral artery, and vasospasm therapy was started. Within 48 hours of symptom onset, the patient gradually improved to a complete neurologic recovery, with normalization of CBF values in the concerning cerebral region. CONCLUSIONS: CIE should always be considered in patients with focal neurologic deficits after iodinate contrast exposure. ASL perfusion MRI with CBF maps could be a promising tool for prompt, early confirmation of underlying vasospasm, as cortical edema and distal vasospasm could not be detected on conventional radiologic imaging.

Increased Arterial Stiffness is Associated with Poor Collaterals in Acute Ischemic Stroke from Large Vessel Occlusion.

BACKGROUND: Cerebral collateral circulation is a network of arterial anastomotic channels capable of providing supplementary perfusion to brain regions in response to ischemic insults. Arterial stiffness could negatively affect collateral circulation development, by means of its effects on the structural intracerebral vasculature. OBJECTIVE: The aim of our study is to investigate a possible link between arterial stiffness and presence of collateral circulation in patients with acute ischemic stroke. METHODS: 113 patients (age: 74±12 years) with acute anterior ischemic stroke underwent neuroimaging examination and 24-hour blood pressure monitoring. Arterial Stiffness Index (ASI) and Pulse Pressure (PP) were assumed as surrogate measures of arterial stiffness. Collateral circulation was evaluated by means of the collateral grading system that was scored on a scale of 0-3. RESULTS: According to TOAST classification, etiology of ischemic stroke was the following: Large-Artery Atherosclerosis (LAA)(n:41), Cardioembolism (CE)(n:60), Undetermined Etiology (UE)(n:12). Logistic regression analysis showed that good predictors of poor collaterals were ASI (OR 2.78 for 0.1, 95% CI:1.19-6.50, p=0.01) and PP (OR 1.81 for 10 mmHg, 95% CI:1.01-3.22, p=0.04) in stroke from LAA. CONCLUSION: Our results suggest that, in patients with ischemic stroke from LAA, arterial stiffness may contribute to the impairment of collateral circulation and, therefore, it could reduce the beneficial effects of acute treatments.

Cerebral circulation time is prolonged and not correlated with EDSS in multiple sclerosis patients: a study using digital subtracted angiography.

Literature has suggested that changes in brain flow circulation occur in patients with multiple sclerosis. In this study, digital subtraction angiography (DSA) was used to measure the absolute CCT value in MS patients and to correlate its value to age at disease onset and duration, and to expand disability status scale (EDSS). DSA assessment was performed on eighty MS patients and on a control group of forty-four age-matched patients. CCT in MS and control groups was calculated by analyzing the angiographic images. Lesion and brain volumes were calculated in a representative group of MS patients. Statistical correlations among CCT and disease duration, age at disease onset, lesion load, brain volumes and EDSS were considered. A significant difference between CCT in MS patients (mean = 4.9s; sd = 1.27 s) and control group (mean = 2.8s; sd = 0.51 s) was demonstrated. No significant statistical correlation was found between CCT and the other parameters in all MS patients. Significantly increased CCT value in MS patients suggests the presence of microvascular dysfunctions, which do not depend on clinical and MRI findings. Hemodynamic changes may not be exclusively the result of a late chronic inflammatory process.

MRI helps depict clinically undetectable risk factors in advanced stage retinoblastomas.

This study compared high-resolution MRI with histology in advanced stage retinoblastomas in which ophthalmoscopy and ultrasonography did not give an exhaustive depiction of the tumour and/or its extension. MRI of orbits and head in 28 retinoblastoma patients (28 eyes) treated with primary enucleation were evaluated. Iris neoangiogenesis, infiltrations of optic nerve, choroid, anterior segment and sclera suspected at MR and histology were compared. Abnormal anterior segment enhancement (AASE) was also correlated with histologically proven infiltrations. Brain images were also evaluated. Significant values were obtained for: prelaminar optic nerve (ON) sensitivity (0.88), positive predictive value (PPV) (0.75) and negative predictive value (NPV) (0.71); post-laminar ON sensitivity (0.50), specificity (0.83), PPV (0.50) and NPV (0.83); overall choroid sensitivity (0.82), and massive choroid NPV (0.69); scleral specificity (1), and NPV (1). AASE correlated with iris neoangiogenesis in 14 out of 19 eyes, and showed significant values for: overall ON PPV (0.65), prelaminar ON sensitivity (0.65), and PPV (0.61), post-laminar ON NPV (0.64); overall choroid sensitivity (0.77), PPV (0.59) and NPV (0.73); scleral NPV (0.83); anterior segment sensitivity (1), and NPV (1). Odds ratios (OR) and accuracy were significant in scleral and prelaminar optic nerve infiltration. Brain examination was unremarkable in all cases. High-resolution MRI may add important findings to clinical evaluation of advanced stage retinoblastomas.

Wake-up (or wake-up for) stroke: a treatable stroke.

A 74-year-old man was admitted to the Emergency Room of our institution with worsening dysarthria, left-side weakness and hypoesthesia (NIHSS score: 5) since his awakening at 7:30 a.m. The evening before, he had gone to sleep at 10:30 p.m. Brain computed tomography (CT) and cervicocranial CT angiography showed low density attenuation of the right caudate nucleus head and lenticular nucleus and sub-total occlusion of ipsilateral middle cerebral artery (MCA) pre-bi/trifurcation M1 segment. Brain CT perfusion showed an ischemic core in the right striatal region, surrounded by a wide region of ischemic penumbra. Although the onset of symptoms, defined as "time last-seen well", was 14 hours before presentation, the following worsening of neurological conditions (NIHSS score: 12) and the evidence of cerebral blood flow / cerebral blood volume mismatch at CT perfusion led us to propose neuroendovascular treatment on the basis of an off-label use. Neuroendovascular treatment by Penumbra system was achieved and the right MCA was only partially recanalized. The patient was discharged with NIHSS score of 12. At six months, modified Rankin scale score was 3. To the best of our knowledge, this is the first Italian case report describing a patient who underwent successful neuroendovascular treatment for a "wake-up stroke" without clinical worsening nor major complications and an acceptable clinical outcome. This was possible thanks to an extension of the therapeutic window guided by CT perfusion.

[Combined radiologic-urologic procedure for the placement of ureteral stent in a case of bilateral iatrogenic ureteral lesion]. / Procedura combinata radiologica-urologica per il posizionamento di stent ureterali in un caso di lesione iatrogena di entrambi gli ureteri.

INTRODUCTION: Iatrogenic ureteral lesions are well-known complications of abdominal and pelvic surgery. A combined radiologic-urologic approach might be necessary to repair these lesions. MATERIALS AND METHODS: A 69-year-old woman underwent bilateral hysteroannessectomy for endometrial cancer. She then became anuric. A CT scan showed multiple urinomas caused by bilateral ureteral lesions. The continuity of the two urinary tracts was restored using ureteral stents in a combined urologic and radiologic procedure. RESULTS: The patient improved clinically and the renal function returned within normal limits. CONCLUSIONS: The combined antegrade-retrograde approach is an effective technique to solve iatrogenic ureteral lesions.

JAG tearing technique with radiofrequency guide wire for aortic fenestration in thoracic endovascular aneurysm repair.

An innovative approach, the JAG tearing technique, was performed during thoracic endovascular aneurysm repair in a patient with previous surgical replacement of the ascending aorta with a residual uncomplicated type B aortic dissection who developed an aneurysm of the descending thoracic aorta with its lumen divided in two parts by an intimal flap. The proximal landing zone was suitable to place a thoracic stent graft. The distal landing zone was created by cutting the intimal flap in the distal third of the descending thoracic aorta with a radiofrequency guide wire and intravascular ultrasound catheter.

Single-center experience and 1-year follow-up results of "sandwich technique" in the management of common iliac artery aneurysms during EVAR.

PURPOSE: Abdominal aortic aneurysm (AAA) accompanied by common iliac artery (CIA) aneurysms requires a more demanding procedure owing to the difficulties in obtaining an adequate distal landing zone for the stent-graft limb(s), a potential site of endoleak. The "sandwich technique" is a procedure to increase EVAR feasibility in the setting of adverse or challenging CIA anatomy. Its main advantages include no restrictions in terms of CIA diameter or length or internal iliac artery (IIA) diameter, no need to wait for a specific stent-graft. Our purpose is to describe our single-center experience and one year follow-up results of this new procedure. MATERIALS AND METHODS: From April 2009 to June 2010, the sandwich technique was performed in our institution in 7 patients treated for AAA and unilateral CIA aneurysms (n. 5) or bilateral CIA aneurysms (n. 2). Inclusion criteria were the presence of unilateral or bilateral CIA aneurysm (independently from its diameter), IIA artery measuring up to 9 mm in its maximum diameter, not dilatation of IIA and EIA. RESULTS: The mean follow-up length was 15 months (range: 14-20 months). All stent-implanted iliac branches remained patent on 1 year follow-up and IIA flow was preserved. None of the patients had symptoms of pelvic ischemia. CT scan follow-up showed aneurysm shrinkage in five patients, without any sign of endoleaks in all cases. CONCLUSIONS: In selected cases, the "sandwich technique" showed good outcomes confirming to be a safe and easy to perform way to overcome anatomical constraints and expanding the limits of EVAR.