Konstantinos Kouskouras

Treatment of Infected Thoracic Aortic Prosthetic Grafts with the In Situ Preservation Strategy: A Review of its History, Surgical Technique, and Results

For cardiothoracic surgeons prosthetic graft infection still represents a difficult diagnostic and treatment problem to manage. An aggressive surgical strategy involving removal and in situ replacement of all the prosthetic material combined with extensive removal of the surrounding mediastinal tissue remains technically challenging in any case. Mortality and morbidity rates following such a major and risky surgical procedure are high due to the nature of the aggressive surgical approach and multi-organ failure typically caused by sepsis. However, removal of the infected prosthetic graft in patients who had an operation to reconstruct the ascending aorta and/or the aortic arch is not always possible or necessary for selected patients according to current alternative treatment options. Rather than following the traditional surgical concept of aggressive graft replacement nowadays a more conservative surgical approach with in situ preservation and coverage of the prosthetic graft by vascular tissue flaps can result in a good outcome. In this article, we review the relevant literature on this specific topic, particularly in terms of graft-sparing surgery for infected ascending/arch prosthetic grafts with special emphasis on staged treatment and the use of omentum transposition.

Diffusion Tensor Imaging in brain tumors: A study on gliomas and metastases

PURPOSE To explore the role of Diffusion Tensor Imaging in preoperative glioma grading, as well as in differentiation between gliomas and metastatic brain tumors. We measured diffusion tensor variables in enhancement and edema regions, which were compared between the different subject groups. MATERIALS AND METHODS We performed DTI in 48 patients (11 Low Grade Gliomas, 27 High Grade Gliomas, 10 Single Metastatic brain tumors). We measured FA, λ1, λ2, λ3, ADC, Cl, Cp, Cs, RA, and VR in enhancing portions of tumors and edema regions. Additionally, ratios of enhancement to edema values were created for each variable. RESULTS In peritumoral edema, Cl and RA were proven to be significantly different in pair-wise comparisons, in addition to ADC, Cp, Cs and VR in enhancement regions. Enhancement to edema values were significantly different as well. CONCLUSION Diffusion tensor indices could be used for the differentiation between low and high grade gliomas, as well as for distinction between gliomas and metastases.

Imaging of the ulcerated carotid atherosclerotic plaque: a review of the literature

Carotid atherosclerotic disease constitutes a major modern health problem whose diagnosis primarily relies on imaging. Grading of stenosis has been long used as the main factor for risk stratification and guiding of management. Nevertheless, increasing evidence has shown that additional plaque characteristics such as plaque composition and surface morphology play an important role in the occurrence of symptoms, justifying the term “vulnerable plaque”. Carotid plaque surface characteristics either in the form of surface irregularities or ulceration represent an important factor of vulnerability and are associated with the occurrence of neurologic symptoms. The delineation of the carotid plaque surface can be performed with virtually all imaging modalities including ultrasound, contrast-enhanced ultrasound, multi-detector computed tomography angiography, magnetic resonance angiography and the traditional reference method of angiography. These techniques have shown varying levels of diagnostic accuracy for the identification of ulcerated carotid plaques or plaque surface irregularities. As a consequence and given its high clinical significance, radiologists should be familiar with the various aspects of this entity, including its definition, classification, imaging findings on different imaging modalities and associations. The purpose of this review is to present the current literature regarding carotid plaque ulcerations and present illustrative images of ulcerated carotid plaques.Teaching Points• Plaque surface and ulceration represent risk factors for stroke in carotid disease.• Characterisation of the plaque surface and ulcerations can be performed with every modality.• US is the first-line modality for carotid disease and identification of ulcerations.• The administration of microbubbles increases US accuracy for diagnosis of carotid ulceration.• MDCTA and MRA are valuable for diagnosing ulceration and evaluating plaque composition.

Radiographic and Ultrasonographic Findings of Uterine Neoplasms in Nine Dogs

The records of nine female intact dogs with histologically confirmed uterine tumors were reviewed retrospectively, and the related radiographic and ultrasonographic signs of the lesions detected were recorded. Radiography revealed a soft-tissue opacity between the urinary bladder and colon in six of seven dogs with uterine body and/or cervical tumors, and a soft-tissue opacity in the midventral abdomen in two dogs with uterine horn tumors. Ultrasonography revealed masses in all dogs with uterine body/cervical tumors and could delineate the origin of the mass in one of two dogs with uterine horn tumors. The mass was characterized ultrasonographically as solid in three dogs (all leiomyomas), solid with cystic component in four dogs (two adenocarcinomas, one leiomyoma, and one fibroleiomyoma), and cystic in two (both leiomyomas). Hyperechoic foci in the mass were observed in three dogs. Ultrasonography was a useful method for demonstrating uterine body and/or cervical tumors. However, it was not possible to ascertain sonographically that a mass originated in a uterine horn unless there was associated evidence of uterine horn to which the mass could be traced. The ultrasonographic appearance of uterine tumors was variable, and the type of neoplasm could only be determined by taking biopsies of the mass.

Contrast-enhanced ultrasonography of the carotids

Contrast-enhanced ultrasonography of the carotids has recently emerged as a complementary examination to conventional carotid Doppler ultrasonography. It is an examination providing improved visualization of the vascular lumen, more accurate and detailed delineation of the vascular wall, and identification of atherosclerotic plaques. Moreover, contrast-enhanced ultrasonography has specific advantages over conventional ultrasonography and plays an important role in the diagnosis of the vulnerable carotid plaque, as it can identify intraplaque neovascularization and carotid plaque ulceration. Given the specific advantages and improved imaging of the carotids provided by this method, radiologists should be familiar with it. This pictorial essay illustrates the advantages of this technique and discusses its value in the imaging of carotid arteries.

Internal Carotid Artery Floating Thrombus in Relapsing Polychondritis

Relapsing polychondritis is a rare autoimmune disease characterized by inflammation of cartilaginous tissues. It may be associated with systemic and cerebral vasculitis and exceptionally with ischemic stroke. Brain infarction associated with internal carotid artery thrombus, in a setting of relapsing polychondritis, has never been reported. We present a 52‐year‐old man without any known risk factors for stroke, treated with prednisone and azathioprine for relapsing polychondritis, who presented a minor left hemisphere stroke. Ultrasound of the neck vessels revealed an isoechogenic thrombus in the left internal carotid artery superimposed on a smooth moderately stenosing isoechogenic atheroma of the carotid bulb. The patient was treated with high‐dose tinzaparin and was followed with serial ultrasound. After 16 days, the thrombus demonstrated a hypoechogenic core surrounded by a hyperechogenic rim and the following day it resolved completely. Thrombus formation on a small unruptured plaque may reflect involvement by relapsing polychondritis of the intimal proteoglycans that hold a role in the development of atheromatosis.

Bilateral secondary neurolymphomatosis of the internal auditory canal nerves: A case report

BACKGROUND Neurolymphomatosis describes the malignant lymphomatous infiltration of nerves. METHODS We encountered a unique case of a 47-year-old patient with non-Hodgkins lymphoma presenting with bilateral sensorineural hearing loss, vestibular dysfunction and bilateral facial nerve palsy. RESULTS Magnetic resonance imaging demonstrated enhancement and thickening of internal auditory canal nerves bilaterally consistent with neurolymphomatosis. Patient was treated with combined intrathecal chemotherapy and total brain irradiation. CONCLUSIONS One must always remain vigilant for metastatic disease in patients with sensorineural hearing loss and/or vestibular dysfunction and facial nerve palsy in the context of known malignancy.

Surgical Management of a Giant Adrenal Pseudocyst: A Case Report and Review of the Literature in the Last Decade

Adrenal pseudocysts are rare entities and occurred in the 5th and the 6th decades of life. They are discovered accidentally, while appearing with nonspecific clinical and imaging findings. We report a case of a 28-year-old woman presented in our Emergency Department complaining about upper abdomen pain. Computed tomography revealed a hypodense cystic lesion containing hyperdense material. The size of a mass was 11. 7 × 9.3 × 6.6 cm in diameter close to the pancreas, but the origin was from the left adrenal gland. The mass was excised with surgical laparotomy. Giant adrenal pseudocysts are rare entities. Final diagnosis usually confirmed with the pathology examination. Management of such adrenal lesions depends on the unique characteristics, the surgeons experience, and local resources.

Repair of Temporal Bone Encephalocele following Canal Wall Down Mastoidectomy

We report a rare case of a temporal bone encephalocele after a canal wall down mastoidectomy performed to treat chronic otitis media with cholesteatoma. The patient was treated successfully via an intracranial approach. An enhanced layer-by-layer repair of the encephalocele and skull base deficit was achieved from intradurally to extradurally, using temporalis fascia, nasal septum cartilage, and artificial dural graft. After a 22-month follow-up period the patient remains symptom free and no recurrence is noted.

Ischemic cerebral infarction in a 5-year-old male child with neurofibromatosis type 1

Stroke is a common cause of neurological disease in children and ranks in the top ten causes of death in the USA, with poor outcome and neurological deficits for the survivors. The annual incidence of pediatric stroke is estimated from 1.3 to 13 cases out of 100,000 population [1]. The broad definition of pediatric stroke includes ischemic and hemorrhagic stroke. In childhood, 55 % of stroke is ischemic and 45 % hemorrhagic, whereas in adults, 85 % of stroke is ischemic [2]. According to the World Health Organization, “ischemic stroke” is a clinical syndrome of rapidly developing focal or global disturbance of brain function lasting more than 24 h or leading to death, caused by arterial or venous infraction (thrombosis or embolism) [3]. Arterial ischemic/hemorrhagic strokes in children usually concern anterior and middle cerebral arteries and their brunches, as also the thalamus and basal ganglia [1]. Children with stroke usually present with hemiparesis, sensory disorders (hemianesthesia), and visual disturbance (hemianopia). Headache is usually present with hemorrhagic stroke, post-traumatic arterial thrombosis, and venous thrombosis. Altered levels of consciousness indicate intracranial hemorrhage, ischemic infarction of the middle cerebral artery, or extensive infarct in the posterior circulation. Seizures mainly occur in cerebral venous sinus thrombosis, most frequently in the neonatal period. Acute onset of clinical presentation usually indicates embolism or acute thrombosis due to posttraumatic rupture of the arterial endothelium, while subacute onset of clinical presentation usually indicates progressive thrombosis [4, 5]. Generally, clinical presentation of pediatric stroke is age dependent. It is also varied and nonspecific, encompassing a broad differential diagnosis. So, the diagnosis of stroke in childhood is often delayed and is rarely made within 6 h of symptom onset [6]. We describe a case of a 5-year-old male child who presented to our clinic with acute right pyramidal tract signs. The aim of this case presentation is to point out the importance of early recognition of pediatric stroke and also to discuss the possible association of neurofibromatosis type 1 (NF1) with intracranial arterial anomalies and problems of blood coagulation.