Spontaneous Dissection of the Superior Mesenteric Artery

Spontaneous dissection of the superior mesenteric artery (SMA) is a rare occurrence, especially when not associated with aortic dissection [1]. Currently, only 28 cases appear to have been reported. Due to the scarcity of cases in the literature, the natural history of isolated, spontaneous SMA dissection is unclear. CT has been reported to be useful for the initial diagnosis of SMA dissection [2–5]. We present two recent cases of spontaneous SMA dissection in which enhanced spiral CT was instrumental in following the disease process and guiding clinical decision making.     

Extracranial Internal Carotid Artery Aneurysms: Report of a Ruptured Case and Review of the Literature

Aneurysms of the extracranial carotid arteries (ECAA) are extremely rare. Schechter et al. [1] documented 835 cases in the literature up to 1977. One hundred and sixteen cases of ECAA have been documented in the Chinese literature since 1981, suggesting a higher prevalence of carotid aneurysmal disease in China than in the West. Four percent of all peripheral artery aneurysms are reported to be ECAA [2]. Those arising from the internal carotid artery (EICAA) are even more rare. Two recent reviews [3, 4] reported 24 and 25 cases of EICAA during 21 and 17 years, respectively, the majority of them is treated surgically. Our literature review revealed only a few true EICAA managed endovascularly, but none of them with a covered stent. We describe a rare such case of ruptured atherosclerotic EICAA which was treated percutaneously.     

Bullet colic

Ureteral obstruction by intramural bullet, buckshot, or related missle following penetrating abdominal trauma is rare; a search of the literature revealed only 4 previously described cases [1-4]. A fifth case of a bullet migrating from the renal pelvis to the ureter has been reported at autopsy [5]. We present 2 new cases of delayed symptomatic ureteral obstruction ("bullet colic") after abdominal gunshot wounds.     

Calcifying pseudoneoplasms of the neuraxis (CAPNON): The great tumor mimicker

Calcifying pseudoneoplasms of the neuraxis (CAPNON) are very rare intracranial lesions with less than 50 cases reported in literature. These are non-neoplastic in etiology and despite having unique imaging characteristics, are often misdiagnosed as a neoplastic condition like meningioma, chordoma and gliomas. These do not have any predilection for any age, gender or intracranial location and can be seen in a wide range of age groups. Despite having an imaging overlap with neoplastic conditions, CAPNONs have classic histopathologic findings including chondromyxoid matrix, palisading spindle cells and calcific or ossific metaplasia. As more cases are being described in literature the imaging features are also being better defined. We discuss the clinical, imaging and histopathological findings of 2 cases of CAPNON mimicking posterior fossa meningioma and glial neoplasm.     

Synovial hemangioma of the hip joint in a pediatric patient

Hemangiomas of the articular synovium are rare and commonly associated with recurrent joint swelling and painful limitation of motion. The knee joint is the most commonly involved site, with most patients diagnosed in the second to third decade of life [1]. Although over 200 cases have been reported in the English-language medical literature, only three have originated within the hip joint, all of which were in adult patients reported in the surgical literature [2–4]. We describe a histologically proven synovial hemangioma of the hip joint in a pediatric patient that invaded the femur, acetabulum, and adjacent soft tissues, with a detailed discussion of the differential diagnosis based on the radiographic and magnetic resonance imaging (MRI) findings.     

Incisional hernia of a normal gallbladder: sonographic and CT demonstration.

The subcutaneous herniation of gallbladder through the abdominal wall is very rare, and to our knowledge, only two cases were reported previously in the literature [Clin. Radiol. 42 (1990) 283; J. Clin. Ultrasound 25 (1997) 398]. In both of these cases, the gallbladders were found to be distended. To our knowledge, the present case is the first case report in the literature in which a morphologically normal gallbladder herniated into the subcutaneous tissue.     

De novo development of presumed cavernomas following resolution of E. Coli subdural empyemas

Cavernomas fall within the group of angiographically occult lesions and may be found in up to 4 % of the population [1]. They may occur at any age, and with the advent of MRI incidental cavernomas are increasingly identified. The pathogenesis is uncertain. Familial cases are well recognised with a reported prevalence of 10–15 % [2–3]. The incidence of new lesions has been reported at 0.4 lesions per patient per year in cases with familial cavernomas [4]. Presumed cavernomas have been documented following radiation for malignancy [5–6], and sterotactic cerebral biopsy [7]. There have been no previously documented cases of de novo genesis of cavernomas following bacterial meningitis and subdural empyemas. Received: 18 November 1999/Accepted: 11 February 2000     

Intradiploic epidermoid tumor of the occipital bone: X-ray,CT, MR findings

Intradiploic epidermoid tumors are extremely uncommon. About 100 cases have been described in the literature [1]. It is thought that they are caused by inclusion of epitelial ectodermal cells in bone tissue during closure of the neural tube. Most of them are asymtomatic and usually detected when plain skull X-rays are made for other reasons. Others may be detected as a palpable lump. They can erode the inner table protuding into the brain. We report a case of an intradiploic epidermoid tumor of the occipital bone studied with plain skull X-rays, Computed tomography and magnetic resonance imaging.Correspondence to: J.M. Pumar Cebreiro     

Odontogenic myxofibroma synchronous with primary angiosarcoma of the spleen

Odontogenic myxofibroma of the temporomandibular joint (TMJ) is a rare tumour; moreover, primary splenic angiosarcoma (PAS) in paediatric patients is extremely rare. We report on a 15-year-old boy who presented with right TMJ swelling and subsequently developed epigastric and right upper quadrant pain. The TMJ swelling proved to be odontogenic myxofibroma and the abdominal pain was a result of primary splenic angiosarcoma with hepatic metastasis. We report for the first time the synchronous presentation of PAS and odontogenic myxofibroma in a paediatric patient, and we describe the radiological features along with the histological diagnosis and clinical outcome. Uptake in ¹⁸F-2-fluoro-2-deoxy-D-glucose positron emission tomography is also described for the first time for both these tumours.Langhans in 1879 was the first to identify primary angiosarcoma of the spleen (PAS). Since then, approximately 200 cases of PAS have been reported in the literature [1]. PAS is a very rare and aggressive neoplasm with poor prognosis, especially in paediatric patients. Only 10 paediatric cases have been reported in the literature [2–6].Odontogenic myxofibroma was first described by Virchow in 1863. It is a rare, locally aggressive, slowly growing benign neoplastic lesion. It is not found in bones outside the facial skeleton. The tumour is asymptomatic, although some patients complain of pain. It occurs in individuals between the ages of 10 years and 30 years, and its occurrence is unusual in people younger than 10 years or older than 50 years [7, 8].¹⁸F-2-fluoro-2-deoxy-D-glucose (¹⁸FDG) positron emission tomography (PET) provides a means of diagnosing cancer based on altered tissue metabolism. This “functional” imaging technique relies on a radioactive substance that decays by positron emission; ¹⁸FDG is an analogue of glucose. Malignant cells trap more radiotracer compared with non-malignant cells, and the local tracer concentration can be measured (standard uptake value (SUV)) [9].We present the case of a 15-year-old male patient with primary angiosarcoma of the spleen, with liver and bone metastases. The patient also had a synchronous temporomandibular joint (TMJ) mass, which proved to be an odontogenic myxofibroma of the TMJ. To our knowledge, this is the first time that both of these neoplasms have presented synchronously and the first time that ¹⁸FDG–PET findings are described for either tumour.     

Gallium-67 scans in renal tumors

The role of gallium-67 is limited in the genitourinary tract [1]. The rare occurrence of increased⁶⁷Ga uptake in renal carcinoma and other tumors is notable because of a lack of documentation in the literature [2]. This report is of such cases found in the last year. Gallium-67 scanning has been performed at our institution since 1972 with an average of 200 cases per year.     

Congenital intrathoracic kidney: A 5-year radionuclide follow-up

Congenital intrathoracic kidney (CIK) is an exceedingly rare anomaly. In a study of 15,919 autopsies of children by Campbell [1], only one CIK was noted. Less than 50 cases have been reported so far in English literature [3]. Most of the CIK are asymptomatic normal organs which require no medical or surgical treatment. We have had the opportunity of applying scintiphotographic techniques exclusively to follow up a 9 1/2-month-old infant with CIK for 5 years.This work was supported by funds provided by the Bureau of Medicine and Surgery, Navy Department, for CR 7-48-1023. The opinions or assertions contained herein are the private ones of the authors and are not to be construed as official or as reflecting the views of the Navy Department or of the naval service at large.     

The diagnostic value of serial brain scanning.

A survey of the literature pertaining to several serial brain scanning procedures has been presented. These procedures include rapid brain imaging, sequential brain imaging, delayed from imaging, and follow-up brain imaging. Applications of these techniques to specific clinical problems have been stressed and the reported results reviewed. Thus, it has been indicated that rapid brain imaging is most useful in detecting lesions secondary to cerebrovascular disease but may also provide some helpful information pertaining to the differential diagnosis of other C.N.S. lesions demonstrated on subsequent static brain scans. Sequential brain imaging is a time-consuming adjunctive procedure which, however, can be extraordinarily helpful in a highly selected group of problem cases which present with relatively small lesions adjacent to normal anatomic structures which themselves have considerable radioactivity. Delayed brain imaging has the distinction of detecting the greatest number of intracranial lesions but is attended by tactical problems in maintaining an optimal patient flow through the department and also has the undesirable consequence of reduced information density and diminished image quality, unless greater radiation doses are injected. Follow-up brain imaging is useful in the differential diagnosis of cerebrovascular and neoplastic disease and in the assessment of effectiveness of radiation therapy.     

CT and ultrasonographic findings in a patient with endometriosis of the bladder after cesarean section

We report ultrasonographic and CT findings in a patient with endometriosis of the bladder wall after cesarean section. Endometriosis is defined as ectopic endometrial tissue which responds to the endocrine changes of the menstrual cycle [1]. The incidence of the condition may be as high as 20% of all menstruating women [2]. The most common locations of endometriosis are in the true pelvis, particularly the fallopian tubes and the ovaries. The sacrouterine ligaments and Douglas' cul-de-sac are also frequently affected. Rarer sites of endometriotic implants include the gastrointestinal tract, urogenital organs, and extraabdominal sites. The diagnosis is suggested by the results of modern imaging techniques and the usually typical clinical findings and is confirmed by histopathology of a surgical specimen. The literature contains few reports on ultrasound and computed tomography (CT) findings in patients with endometriosis [3, 4]. Correspondence to: K. W. Preidler     

CT and MRI findings in gliomatosis cerebri: a neuroradiologic and neuropathologic review of diffuse infiltrating brain neoplasms

The aim of the study was to develop objective criteria that might be helpful for the diagnosis of gliomatosis cerebri (GC) with the highest possible probability based on both the neuroradiological and histopathological findings. Imaging findings in 14 patients with diffuse infiltrating brain neoplasms were studied by two neuroradiologists. Computed tomography and MRI scans were compared with each other side by side. The extent and kind of disease were graded on a scale of 1–5. Interexamination agreement between the two methods was calculated using a kappa analysis. Neither of the neuroradiologists performed the examinations and both were blinded to the histopathological findings, which were also available for all patients, based on biopsy as well as follow-up CT and MRI studies. A neuroradiological–neuropathological correlation was performed. A score system helped to differentiate the findings in three categories: 1 = suggestive of GC; 2 = GC cannot be excluded; and 3 = others. Both CT and MRI were performed in 14 patients with clinical signs and symptoms of an intracerebral tumor. All examinations had diagnostic quality and showed the involvement of at least two brain lobes. Stereotactic biopsy was carried out in all patients. In 2 patients the neuropathological diagnosis was suggestive of GC, in 1 patient glioblastoma, in 2 patients astrocytoma, and in 5 patients nonspecific astrogliotic proliferation. In the remaining 4 cases anaplastic tumor infiltration was diagnosed. The neuroradiological findings in 5 cases were suggestive of GC; in 6 cases a GC could not excluded; and in 3 patients only a slight probability of GC was found. In 2 cases was the neuropathological and the neuroradiological diagnosis of GC concordant. Magnetic resonance imaging is significantly more sensitive than CT in the diagnosis of GC. However, even with multiple, MRI-guided stereotactic biopsies in correlation with intraoperative analysis of the sample by smear preparations by a neuropathologist the antemortem diagnosis of GC is still difficult. Discussion of neuropathological and neuroradiological findings in each case in combination with a score system may help to resolve discrepancies. Received: 3 March 2000/Revised: 1 August 2000/Accepted: 4 August 2000     

Congenital intrahepatic portosystemic venous shunt: sonographic and magnetic resonance imaging

We report an intraheptic portosystemic venous shunt (IPVS) detected by ultrasound in an asymptomatic newborn. The lesion, which was further documented using color Doppler ultrasound and magnetic resonance imaging (MRI), had almost totally disappeared 6 months later without any treatment. Intraheptic portosystemic venous shunts (IPVS) are uncommon and their etiology is controversial. Some cases of IPVS have been reported in the literature, most of them in adult patients with portal hypertension and cirrhosis of the liver [1–3]. However, only scattered reports describe IPVS in the absence of liver pathology [4–8]. A revision of the proposed etiologies of IPVS is made and the usefulness of gray-scale and color Doppler sonography and MRI in diagnosing IPVS is discussed.     

Clinical applications of dynamic susceptibility contrast perfusion-weighted MR imaging in brain tumours

Magnetic resonance imaging (MRI) with a dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) sequence to study brain tumours provides information on the haemodynamic characteristics of the neoplastic tissue. Brain perfusion maps and calculation of perfusion parameters, such as relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV) and mean transit time (MTT) allow assessment of vascularity and angiogenesis within tumours of the central nervous system (CNS), thus providing additional information to conventional MRI sequences. Although DSC-PWI has long been used, its clinical use in the study of brain tumours in daily clinical practice is still to be defined. The aim of this review was to analyse the application of perfusion MRI in the study of brain tumours by summarising our personal experience and the main results reported in the literature.     

Investigation on Changes of Optical Tissue Properties related to iPDT on Malignant Gliomas

Brain tumor treatment via interstitial photodynamic therapy (iPDT) needs precise treatment light delivery, which is essential for the conduction of the therapy [1]. The light delivery and the resulting light dosimetry are highly dependent on the optical tissue properties of the tumor tissue and the surrounding brain tissue. Employing intraoperative spectral online monitoring (SOM), it looks possible to assess the treatment light transmittance between the used light applicators and monitor potential changes during therapy [2]. Changes have been observed during clinical iPDT-illumination and can be interpreted as changes in the optical tissue properties [2, 3]. In vitro experiments mimicking the clinical iPDT-illumination situation using liquid optical tissue phantoms, including blood, showed SOM intensity changes in transmittance. Due to simultaneous remission spectroscopy, this can be related to the deoxygenation of hemoglobin and its oxidation to methemoglobin (MetHb) [4]. The analysis of data from clinical iPDT-procedures confirmed this interpretation. Based on intraoperative SOM data, changes in the optical absorption coefficient have been calculated and correlated with newly diagnosed early visible intrinsic T1-hyperintensity in the treatment volume [3]. The intrinsic T1 hyperintensity is clinically an indicator of the formation of MetHb after silent hemorrhages, which may occur during iPDT. As the T1 hyperintensity was early visible in the MRI, the corresponding early appearance of MetHb was in context with the iPDT and consistent with the in vitro experiments. Further in vitro experiments showed that changes in optical tissue properties and hemoglobin oxidation is not only possible due to ROS production during iPDT but also due to a slight temperature increase during iPDT by 4°C [5]. These results give more insight into mechanisms occurring during iPDT irradiation, but the impact on treatment outcome has still to be assessed.     

A rare case of gliomatosis cerebri lurking beneath the shadows of a stroke mimic

Gliomatosis cerebri (GC) is a diffuse infiltrative neoplastic glial process with a devastating prognosis. Considering its rarity, unpredictable clinical manifestations, and lack of characteristic radiographic features, GC is a difficult diagnosis that is quite often delayed. In this report, we present a case of a 61-year-old man with a history of chronic alcohol abuse and atrial fibrillation who presented with right arm weakness initially presumed to be from an acute ischemic stroke. GC was not diagnosed until six months after initial symptoms and diagnosis was indicated when considering the neurocognitive findings in conjunction with suggestive radiographic findings. The presence of a rapid, expansile lesion in the cortex, corpus callosum, and infratentorial structures with mild parenchymal enlargement, as shown in our case, is more revealing of an invasive entity typical of GC rather than an ischemic process and other pathologies. This case demonstrates the fatal challenges of its prompt recognition and the therapeutic limitations for those patients presenting with advanced symptoms at the time of diagnosis. Recognizing GC in cases with such rapid multilobe clinical features with similar diffusely invasive patterns of growth on imaging can avoid a delay in diagnosis and improve patient quality of life.     

Use of 3-acetoxymethoxycarbonyl-2,2,5,5-tetramethyl-1-pyrrolidinyloxyl as an EPR oximetry probe: potential for in vivo measurement of tissue oxygenation in mouse brain.

Measurement of oxygen concentration and distribution in the brain is essential for understanding the pathophysiology of stroke. Low-frequency electron paramagnetic resonance (EPR) spectroscopy with a paramagnetic probe is an attractive imaging modality that potentially can be used to map O(2) concentration in the brain. We examined two nitroxides, 3-methoxycarbonyl-2,2,5,5-tetramethyl-1-pyrrolidinyloxyl [2] and 3-acetoxymethoxycarbonyl-2,2,5,5-tetramethyl-1-pyrrolidinyloxyl [3], as pro-imaging agents to deliver 3-carboxy-2,2,5,5-tetramethyl-1-pyrrolidinyloxyl [1] across the blood-brain barrier (BBB). In primary cultured neurons, nitroxide [3] but not [2] was hydrolyzed by intracellular esterases to [1], which, being anionic at physiologic pH, was well retained intracellularly. In contrast, [2] was not well retained by neurons. In vivo pharmacokinetic and pharmacodynamic studies in mice suggested that esterase-labile nitroxide [3] crossed the BBB, and was converted to [1] and retained. Retention occurred in brain tissue and not in the extensive vasculature, as evidenced by the fact that removal of blood by whole-body saline perfusion did not eliminate the nitroxide EPR signal from the brain. The EPR linewidths of [1] and [3] were more O(2)-sensitive than that of the commonly-used oximetry probe 4-oxo-2,2,6,6-tetramethylpiperidine-d(16)-1-(15)N-oxyl [4]. Moreover, we used [3] in vivo to estimate O(2) concentration in mouse brains. These results indicate that nitroxide [3] could be useful for mapping O(2) distribution in the brain following stroke.