Maciej Guziński

Quantitative MR evaluation of atrophy, as well as perfusion and diffusion alterations within hippocampi in patients with Alzheimer’s disease and mild cognitive impairment

Background The aim of this study was to evaluate atrophy rates, perfusion, and diffusion disturbances within the hippocampus, which is the site of characteristic changes in Alzheimer’s disease (AD) and mild cognitive impairment (MCI). Material/Methods Thirty patients with AD (mean age 71.2 yrs) – 34 with MCI (mean age 67.7 yrs) and 20 healthy controls (mean age 68.1 yrs) – underwent structural MR examination followed by perfusion and diffusion-weighted imaging on a 1.5 T scanner. Visual rating of hippocampal atrophy, planimetric measurements of hippocampal formation (HF) and perihippocampal fluid spaces (PFSs), and values of relative cerebral blood volume (rCBV) and apparent diffusion coefficient (ADC) were assessed. The results were correlated with the MMSE scores. Results In AD we found decreased size of HF and increased diameters of PFSs and ADC values, compared to MCI and control group. Compared to normal controls, the MCI group showed decreased HF size and increased diameters of only medial PFS. There were no differences in rCBV values among all the subject groups. Planimetric measurements of hippocampal atrophy showed the highest accuracy in diagnosing AD and MCI. In all patients, the increased rates of hippocampal atrophy correlated with the increased ADC values. In MCI, MMSE scores correlated with the HF size and ADC values. Conclusions In AD and MCI, hippocampal atrophy is associated with decreased tissue integrity without coexisting perfusion disturbances. Of all evaluated hippocampal measurements, atrophy rates seem to be the most useful parameters in detecting changes among AD, MCI, and control subjects.

Usefulness of perfusion weighted magnetic resonance imaging with signal-intensity curves analysis in the differential diagnosis of sellar and parasellar tumors: Preliminary report

PURPOSE The most common pituitary tumors are adenomas, which however may be mimicked by other tumors that can show a very similar appearance in plain MRI. The aim of our study was to evaluate the usefulness of perfusion weighted MR imaging (PWI), including signal-intensity curves analysis in the differential diagnosis of sellar/parasellar tumors. METHODS Forty-one patients with sellar/parasellar tumors (23 macroadenomas, 10 meningiomas, 5 craniopharyngiomas, 1 intrasellar hemangioblastoma, 1 intrasellar prostate cancer metastasis, 1 suprasellar glioma), underwent plain MRI followed by PWI using a 1.5T unit. In each tumor, the mean and maximum values of relative cerebral blood volume (rCBV), as well as the relative peak height (rPH) and the relative percentage of signal intensity recovery (rPSR) were calculated. RESULTS The high perfusion tumors were: macroadenomas, meningiomas, squamous-papillary type of craniopharyngiomas, hemangioblastoma, glioma and metastasis. The low perfusion neoplasms included adamantinomatous type of craniopharyngiomas. By comparing adenomas and meningiomas, we found statistically significant differences in the mean and maximum rCBV values (p=0.026 and p=0.019, respectively), but not in rPH and rPSR. The maximum rCBV values >7.14 and the mean rCBV values >5.74 with the typical perfusion curve were very suggestive of the diagnosis of meningioma. There were differences between adenomas and other high perfusion tumors in rPH and rPSR values. CONCLUSIONS PWI can provide additional information helpful in differential diagnosis of sellar/parasellar tumors. In our opinion PWI, as an easy to perform and fast technique should be incorporated into the MR protocol of all intracranial neoplasms including sellar/parasellar tumors.

Clinical and radiological features of nonfamilial cherubism: A case report.

Summary Background: Cherubism is an uncommon hereditary benign fibro-osseous disorder characterized by bilateral enlargement of the mandible and the maxilla that presents with varying degrees of involvement and a tendency toward spontaneous remission. On radiography cherubic lesions appear as cystic multilocular radiolucencies limited to the jaw bones. Case Report: A 5-year-old boy was referred to the Department of Maxillo-Facial Surgery due to deformation of the lower and middle section of the face and displacement or absence of teeth. A panoramic radiograph and a computed tomography revealed extensive multilocular, bilateral radiolucent areas and marked bony expansion in the mandible and maxilla, with sparing of the mandibular condyles. Histopathological evaluation of an incisional biopsy of the left maxilla and genotypic characterization confirmed the diagnosis of cherubism. Conclusions: The radiologic characteristics of cherubism are not pathognomonic but the diagnosis is strongly suggested by bilateral relatively symmetric jaw involvement that is limited to the jaw bones and, together with clinical and histopathologic findings, enables the diagnosis of cherubism. Genotypic characterization confirms the diagnosis.

Size-Specific Dose Estimates for Evaluation of Individual Patient Dose in CT Protocol for Renal Colic

OBJECTIVE The purpose of this study is to retrospectively evaluate size-specific dose estimates of a renal-colic CT protocol and to assess the quality and diagnostic value of obtained images. MATERIALS AND METHODS The study population included 82 consecutive adult patients with acute renal colic undergoing CT with a reduced radiation dose (noise index, 59.1). The control group included 82 consecutive patients who underwent clinically indicated CT examination of the abdomen and pelvis with a routine-dose CT protocol (noise index, 22.0). The size-specific dose estimate was calculated with volume CT dose index and patient effective diameter. Subjective image quality analysis was based on visibility of the ureter. Ureters were tracked from the renal pelvis to the vesicoureteral junction. Objective image quality was based on the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR). RESULTS The size-specific dose estimates in the renal-colic group were 2.7 times lower than those in the control group. A linear relationship between patient size and size-specific dose estimate was noted. In the smallest patient, the conversion factor for the size-specific dose estimate calculation was 1.65. Overall image quality was better for the control patients, but there was no statistically significant difference in ureter visibility. The SNR was higher for the control group, whereas no difference in CNR was found. CONCLUSION Small patients need the biggest correction for body size and require special attention in radiation dose estimation. We suggest the modification of scanning parameters on the basis of size-specific dose estimate to decrease patient dose in large patients.

Imaging difficulties in Takayasu arteritis - case report and review of the literature.

Summary Background: Takayasu arteritis is an inflammatory disease of large-diameter arteries. Aorta and its branches are most frequently affected. Takayasu arteritis occurs mainly in young women and, if left untreated, leads to fatal complications. Digital subtraction angiography (DSA) is considered the gold standard in imaging of Takayasu arteritis. Case Report: A thirty-five-year-old woman was admitted to the hospital with transient loss of consciousness, effort-associated vertigo, upper limb weakness and temporary vision problems. On admission, there was no pulse on the left radial artery while there were bruits over subclavian arteries. Imaging of the aortic arch (computed tomography angiography, DSA) revealed stenoses of its main branches, indicating Takayasu arteritis. Conclusions: Computed tomography angiography (CTA) performed with a 64-slice unit revealed high effectiveness in localization of vascular wall and lumen pathologies resulting from Takayasu arteritis. Thanks to this fast diagnostic method, it is now possible to perform successful monitoring of patients with Takayasu arteritis and to plan possible interventional treatment.

Balloon Dilatation for Removal of an Irretrievable Permanent Hemodialysis Catheter: The Safest Approach.

Long-term hemodialysis catheter dwell time in the central vein predisposes to fibrin sheath development, which subsequently causes catheter malfunction or occlusion. In very rare cases, the catheter can be overgrown with fibrin and rigidly connected with the vein or heart structures. This makes its removal almost impossible and dangerous because of the possibility of serious complications, namely vein and heart wall perforation, bleeding, or catheter abruption in deep tissues. We describe two cases in which standard retrieval of long-term catheters was not possible. Balloon dilatation of catheter lumens was successfully used to increase the catheter diameter with simultaneous tearing of the fibrin sheath surrounding it. This allowed the catheter to be set free safely. Based on this experience, we present recent literature and our point of view.

Original Protocol Using Computed Tomographic Angiography for Diagnosis of Brain Death: A Better Alternative to Standard Two-Phase Technique?

BACKGROUND The application of computed tomographic angiography (CTA) for the diagnosis of brain death (BD) is limited because of the low sensitivity of the commonly used two-phase method consisting of assessing arterial and venous opacification at the 60th second after contrast injection. The hypothesis was that a reduction in the scanning delay might increase the sensitivity of the test. Therefore, an original technique using CTA was introduced and compared with catheter angiography as a reference. MATERIAL AND METHODS In a prospective multicenter trial, 84 clinically brain-dead patients were examined using CTA and catheter angiography. The sensitivities of original CTA technique, involving an arterial assessment at the 25th second and a venous assessment at the 40th second, and the standard CTA, involving an arterial and venous assessment at the 60th second, were compared to catheter angiography. RESULTS Catheter angiography results were consistent with the clinical diagnosis of BD in all cases. In comparison to catheter angiography, the sensitivity of original CTA technique was 0.93 (95%CI, 0.85-0.97; p<0.001) and 0.57 (95%CI, 0.46-0.68; p<0.001) for the standard protocol. The differences were statistically significant (p=0.03 for original CTA and p<0.001 for standard CTA). Decompressive craniectomy predisposes to a false-negative CTA result with a relative risk of 3.29 (95% CI, 1.76-5.81; p<0.001). CONCLUSIONS Our original technique using CTA for the assessment of the cerebral arteries during the arterial phase and the deep cerebral veins with a delay of 15 seconds is a highly sensitive test for the diagnosis of BD. This method may be a better alternative to the commonly used technique.

The Usefulness of the TOAST Classification and Prognostic Significance of Pyramidal Symptoms During the Acute Phase of Cerebellar Ischemic Stroke.

Cerebellar stroke is a rare condition with very nonspecific clinical features. The symptoms in the acute phase could imitate acute peripheral vestibular disorders or a brainstem lesion. The aim of this study was to assess the usefulness of the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification in cerebellar stroke and the impact of clinical features on the prognosis. We retrospectively analyzed 107 patients with diagnosed ischemic cerebellar infarction. We studied the clinical features and compared them based on the location of the ischemic lesion and its distribution in the posterior interior cerebellar artery (PICA), superior cerebellar artery (SCA), and anterior inferior cerebellar artery (AICA) territories. According to the TOAST classification, stroke was more prevalent in atrial fibrillation (26/107) and when the lesion was in the PICA territory (39/107). Pyramidal signs occurred in 29/107 of patients and were more prevalent when the lesion was distributed in more than two vascular regions (p = 0.00640). Mortality was higher among patients with ischemic lesion caused by cardiac sources (p = 0.00094) and with pyramidal signs (p = 0.00640). The TOAST classification is less useful in assessing supratentorial ischemic infarcts. Cardioembolic etiology, location of the ischemic lesion, and pyramidal signs support a negative prognosis.

Embolization of a True Giant Splenic Artery Aneurysm Using NBCA Glue - Case Report and Literature Review.

Summary Background Although splenic artery aneurysms (SAAs) are common, their giant forms (more than 10 cm in diameter) are rare. Because of the variety of forms and locations of these aneurysms, there are a lot of therapeutic methods to choose. In our case of a giant true aneurysm we performed an endovascular embolization with N-butyl-cyano-acrylate (NBCA) glue. To our knowledge it is the first reported case of this method of treatment of true giant SAA. Case Report A 74-year-old male patient with symptomatic giant SAA (13 cm) was urgently admitted to our hospital for the diagnostic and therapeutic procedures. Due to the general health condition, advanced age and the large size of the aneurysm we decided to perform an endovascular treatment with N-butyl-cyano-acrylate (NBCA) glue. Conclusions The preaneurysmal part of splenic artery was occluded completely with exclusion of the aneurysm. No splenectomy was needed. The patient was discharged in good general condition Embolization with NBCA can be an efficient method to treat the giant SAA.

Dolichoectasia of the circle of Willis arteries and fusiform aneurysm of basilar artery - case report and review of the literature.

Summary Background: Dolichoectasia of intracranial arteries is a rare arteriopathy characterized by elongation and widening of the arteries and disturbance of the laminar blood flow. It involves mostly vertebral and basilar arteries. In advanced cases, formation of a fusiform aneurysm is possible. Case Report: A sixty-four-year-old female with hypertension was admitted to the hospital with severe non-systemic vertigo and dysarthria, which had lasted for a couple of weeks. Imaging of the brain revealed dolichoectasia of arteries of the circle of Willis coexisting with a fusiform aneurysm of the basilar artery. Conclusions: Intracranial arterial dolichoectasia may be asymptomatic for a long time. However, in many cases it leads to neurological symptoms associated with haemodynamic disturbance (due to unstable wall clots) and mass effect caused by the widened vessel.