Akin Levent

How Can New Imaging Modalities Help in the Practice of Radiology

The purpose of this article was to provide an up-to-date review on the spectrum of new imaging applications in the practice of radiology. New imaging techniques have been developed with the objective of obtaining structural and functional analyses of different body systems. Recently, new imaging modalities have aroused the interest of many researchers who are studying the applicability of these modalities in the evaluation of different organs and diseases. In this review article, we present the efficiency and utilization of current imaging modalities in daily radiological practice.

Extra-articular contrast material leaks into locations unrelated to the injection path in shoulder MR arthrography

AbstractObjectivesTo evaluate the localisation, frequency and amount of extravasation in patients with extra-articular contrast material leak into locations unrelated to the injection path in shoulder magnetic resonance (MR) arthrography and associated shoulder disorders.MethodsThe sites of extravasation were determined on the shoulder MR arthrography of 40 patients. The extravasations were measured on three vertical planes of the MR arthrography. Sufficient joint distension was assessed according to the transverse diameters of the axillary recess on coronal MR images.ResultsExtravasation of the contrast material occurred through the subscapular recess, the synovium of the biceps, and the axillary recess. In four cases, extravasations were observed in more than one anatomic location. The most common site of extravasation was along the subscapularis muscle. Superior labrum anterior-posterior (SLAP) lesions were found to be most frequently associated with extravasations. The amount of extravasation was significantly higher in patients with adhesive capsulitis compared with the patients with a different diagnosis (p = 0.022).ConclusionsThe extravasations adjacent to the axillary recess do not always indicate glenohumeral ligament pathology. Massive subscapular extravasations were most frequently associated with adhesive capsulitis and SLAP lesions, and might be considered in the MR arthrography report.Key Points• Contrast material extravasation may reduce the diagnostic value of shoulder MR arthrography. • The extravasations may occur into locations unrelated to the injection path. • The extravasations adjacent to axillary recess can be misleading for HAGL lesion. • Massive subscapular extravasations were frequently associated with adhesive capsulitis and SLAP lesions.

Diagnostic efficiency of multidetector computed tomography with multiplanar reformatted imaging and virtual cystoscopy in the assessment of bladder tumors after transurethral resection.

Purpose: In the assessment of recurrent bladder tumors, diagnostic efficiency of virtual cystoscopy carried out by multidetector computed tomography (MDCT) was investigated and compared with the criterion standard of conventional cystoscopy. Materials and Methods: Twenty-seven patients between 39 and 83 years who had undergone transurethral resection because of bladder tumors were assessed using virtual and conventional cystoscopy. Virtual cystoscopy was performed using a 16-MDCT (Aquilion, Toshiba Medical Systems, Tokyo, Japan) in the supine and prone positions. After axial scanning, the 2-dimensional axial images were assessed, followed by coronal and sagittal multiplanar reconstruction of the images. In addition, virtual cystoscopy and cystographic investigations were performed using software in which volume-rendering technical algorithms shaded the surface display. In the images obtained, the existence and localization of lesions, morphological features, environment invasions, involvement of lymph nodes, and, if any, metastases of abdomen were assessed. Results: For bladder pathologies, the sensitivity and specificity of CT cystography coupled with virtual cystoscopy were 91% and 92%, respectively. The percentage of correct diagnoses using CT cystography was 92%. In addition to bladder pathologies, we investigated liver metastases, kidney cysts, fluid in abdomen, and lymphadenopathies. Conclusions: Using MDCT with virtual cystoscopy to assess primary bladder tumors and, in particular, to determine tumor recurrence after transurethral resection is a minimally invasive method that can be used in the long-term follow-up care of patients.

Contrast-Enhanced and Time-of-Flight MR Angiographic Assessment of Endovascular Coiled Intracranial Aneurysms at 1.5 T.

This study evaluated contrast-enhanced magnetic resonance angiography (CE-MRA) and three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) through comparisons with digital subtraction angiography (DSA) for the follow-up of intracranial aneurysms treated with detachable coils. Sixty-seven patients with 79 aneurysms underwent 3D-TOF-MRA, CE-MRA, and catheter angiography one year after coiling. Two independent observers classified recanalization status on images as neck or body remnant or no recanalization. For 3D-TOF-MRA and CE-MRA, the intermodality agreement, interobserver agreement, and correlation with angiography were assessed. Sixty-seven patients with 79 coiled aneurysms agreed to participate in the study. Three aneurysms could not be detected on 3D-TOF-MRA, so they were excluded from this study. Interobserver agreement was very good for 3D-TOF-MRA and CE-MRA (kappa (κ): 0.87, 0.94, respectively). Correlation of TOF-MRA with angiography was good (κ: 0.76). Correlation of CE-MRA with angiography was excellent (κ: 0.91). The sensitivity and specificity of TOF-MRA were 92% and 98%, respectively. The sensitivity and specificity of CE-MRA were 96% and 98%, respectively. After selective embolization of intracranial aneurysms, CE-MRA is useful and comparable to DSA in the assessment of aneurysmal recanalization. Agreement with the gold standard is stronger with CE-MRA than with 3D-TOF-MRA.

Leptomeningeal Dissemination of Intraventricular Rhabdoid Meningioma: Imaging Findings.

A 20-year-old male patient was admitted to our clinic with a 1-year history of headache. The patients systemic-neurological examination and laboratory findings were normal. Computed tomography and magnetic resonance imaging were performed. Imaging findings showed calcified intraventricular mass and subependymal and gyral nodular lesions. There was a slight increase in ventricular volume. Surgical treatment was performed. Pathological specimens revealed the diagnosis of rhabdoid meningioma. Leptomeningeal dissemination refers to diffuse seeding of the leptomeninges by tumor metastases. To our knowledge, leptomeningeal dissemination of intraventricular rhabdoid meningioma is very rare in the literature. We aimed to discuss imaging findings and differential diagnosis of leptomeningeal dissemination of rhabdoid meningioma.

Cerebral dural arteriovenous fistula that causes intermittent headache.

A 45-year-old man underwent multislice computed tomography for complaint of intermittent diffuse headaches of 3 years in duration. A computed tomography-angiography axial slice image revealed dilated intraosseous diploic veins, or extatic dural arterial branches (Fig. 1A). A computed tomography 3-dimensional image showed feeding vessels (the internal maxillary, middle meningeal, superficial temporal, or occipital arteries) on the calvarium (Fig. 1B). Catheter angiogram was carried out and showed connections between meningeal arteries and dural sinuses, which resulted in the diagnosis of dural arteriovenous fistula (Fig. 2). In this case surgical management was performed and the patient remained well after the procedure. Dural arteriovenous fistulas (DAVFs) are a rare but potentially treatable neurological condition resulting from abnormal connections between meningeal arteries and dural sinuses. Dural arteriovenous fistulas account for approximately 10–15% of all intracranial vascular malformations and occur most commonly along the transverse and sigmoid sinuses. Cognard defined 5 types of DAVFs based exclusively upon the pattern of venous outflow: type I, located in the main sinus,with antegrade flow;type II, in the main sinus, with reflux into the sinus (II a), cortical veins (II b), or both (II a + b); type III, with direct cortical venous drainage without venous ectasia; type IV, with direct cortical venous drainage with venous ectasia; and type V, with spinal venous drainage. Dural arteriovenous fistulas can be clinically grouped into benign (asymptomatic, bruit, headache, tinnitus or ocular symptoms), and aggressive (hemorrhage or dementia). Blood flow return to the brain is called “cortical venous reflux.” Dural arteriovenous fistula draining retrograde into cortical veins exhibits a much higher incidence of hemorrhage or venous infarction. Increased pressure within the dural venous sinuses may result hemorrhage or nonhemorrhagic neurologic deficits. Intracranial hemorrhage has been reported in up to 35–42% of DAVFs and is thought to be caused by the rupture of congested cortical veins (secondary to retrograde venous drainage). This hemorrhage may be intraparenchymal or within the subarachnoid/subdural space. Treatment varies depending on the type and location of the fistula. Some fistulas can be embolized through endovascular approach or, alternatively, surgery to clip or separate the abnormal connection can be performed. From the Department of Radiology, School of Medicine, Atatürk University, Erzurum, Turkey (M. Kantarci, Ü. Bayraktutan, M. Özgökçe, S. Eren, and A. Levent); Department of Neuroradiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey (S. Albayram). ISSN 0017-8748 doi: 10.1111/j.1526-4610.2012.02093.x Published by Wiley Periodicals, Inc. Headache

Comparison of Ultrasonography and Low-Dose Computed Tomography for the Diagnosis of Pediatric Urolithiasis in the Emergency Department

OBJECTIVE This study aimed to compare ultrasonography (US) and low-dose computed tomography (LDCT) for diagnosing pediatric urolithiasis in the emergency department. MATERIALS AND METHODS This retrospective study was approved by our institutional ethics committee, and informed consent was waived. From March 2016 to March 2017, 100 consecutive patients met the selection criteria and were enrolled in the study. Patients were randomly selected in a 1:1 ratio and were allocated to one of the following two imaging groups: US or abdominal LDCT. LDCT examinations were performed using a 320-detector row CT. Radiation dose analysis was performed using Radimetrics. US examinations were performed using the Aplio 500 ultrasound system. The presence of urolithiasis, anatomical location of urolithiasis, and measurements of renal stones were evaluated and recorded. RESULTS There were statistically significant differences between US and standard-dose CT (SDCT) with respect to the diagnosis of urolithiasis, anatomical location of urolithiasis, and measurements of renal stones (p<0.001, p=0.005, and p=0.03, respectively). The mean effective radiation dose of LDCT was 1.44±0.34 mSv and that of SDCT was calculated to be 4.36±1.33 mSv. There was no statistically significant difference between LDCT and SDCT with regard to the diagnosis of urolithiasis, anatomical location of urolithiasis and measurements of renal stones (p=1 for all). The diagnostic accuracy of US and LDCT was 0.68 and 1.0, respectively. CONCLUSION Low-dose computed tomography had 1/3 SDCT radiation dose, and LDCT and SDCT accurately diagnosed pediatric urolithiasis in the emergency department. US had a lower accuracy than SDCT and LDCT for diagnosing pediatric urolithiasis in the emergency department. LDCT can be an alternative for SDCT for diagnosing pediatric urolithiasis.

Pancake kidney with bladder herniation.

A 61-year-old man presented to the Emergency Department with vomiting and progressively worsening abdominal pain. A computed tomography (CT) was performed. The diagnosis of patient was acute cholecystitis and the patient was referred to general surgery clinic. In addition CT scan showed bilateral ectopic kidneys with urinary bladder herniation (Figures 1 and 2). Both kidneys were fused at the medial borders of each pole. To our knowledge, the case of pancake kidney with bladder herniation was not published yet in the literature. Pancake kidney is very rare type of congenital fusion anomaly of the kidney. It is described as a renal mass located in the pelvis which is formed by complete medial fusion of renal parenchyma without intervening septum (1). Each kidney has its own collecting system and anteriorly placed short ureters entering the bladder orthotopically (1). The presence of a pancake kidney may predispose the formation of stones due to the probable rotation anomaly of the collecting system and short ureters which are prone to stasis and obstruction. Patients with pancake kidney are usually asymptomatic, but may present with features of urinary tract infection, fever and vague lower abdominal pain (1). If a pancake kidney has to undergo surgery, division of the parenchyma presents potential problems such as renal vascular damage, postoperative renal failure and eventual renal failure (2). Asymptomatic cases can be managed conservatively with long-term follow-up of renal function (1). If there are symptoms of renal failure, surgery is warranted. Ultrasonography, excretory urography and CT were efficient in detection and evaluation of pancake kidney anomaly (1).

Predictive Role of the Cervical Sympathetic Trunk Ischemia on Lower Heart Rates in an Experimentally Induced Stenoocclusive Carotid Artery Model by Bilateral Common Carotid Artery Ligation

Bilateral common carotid artery ligation (BCCAL) leads to acute craniocervicocerebral ischemia, retrograde blood flow, increased blood pressure, and significant hemodynamic and histomorphological changes at the posterior cerebral vasculature. We examined the potential relationship between denervation injury following BCCAL-induced cervical sympathetic trunk (CST) ischemia and heart rate after permanent BCCAL. Rabbits (n = 25) were randomly divided into three groups: an unoperated control group (GI, n = 6); a sham-operated control group (GII, n = 6), and an experimental group subjected to BCCAL (GIII, n = 13); and then followed for one month. All animals were then sacrificed and the stellate ganglia (STGs) were examined histologically using stereological methods. The densities of degenerated neurons in the STGs were compared with heart rates and the results were analyzed with the Mann–Whitney U test. The mean normal neuron density in STGs was 10.340 ± 954/mm3 and the degenerated neuron density was 12 ± 3/mm3 in the GI group (p > 0.5). The mean heart rates and degenerated neuron densities of STGs were recorded as 267 ± 19/min and 237 ± 45/mm3 in GII (p < 0.005 for GII vs. GI); and 190 ± 11/min 1421 ± 230/mm3 in GIII (p < 0.0001 for GIII vs. GI and p < 0.005 for GIII vs. GII). An inverse and meaningful association was observed between the heart rate and degenerated neuronal density in the STGs. BCCAL may lead to hazardous histomorphological changes in the CST. A high density of degenerated neurons in the STG may provoke excessive sympathetic hypoactivity-related cardiac damage and bradyarrhythmias after stenoocclusive carotid artery diseases.

A Case of Primary Postpartum Bleeding due to Vaginal Laceration after Vaginal Delivery: Successful Management with Transcatheter Arterial Embolization.

Postpartum hemorrhage is one of the major causes of maternal mortality. There are medical and surgical options to control the bleeding, some of which can impair future fertility. Transcatheter arterial embolization might be a useful option in the management of intractable postpartum bleeding before the consideration of more invasive and radical methods. In this report, we report a 33-year-old patient who presented with primary postpartum hemorrhage due to vaginal laceration and was eventually treated with transcatheter arterial embolization.