Dynamic computed tomography angiography for noninvasive diagnosis of bow Hunter's syndrome: a case report.

The focus of this case report is to technically describe a noninvasive diagnostic evaluation of bow Hunter's syndrome using a dynamic computed tomography angiography protocol and discuss its advantages. In addition, we aimed to exemplify the quality of the study by presenting images of a 3D-printed model generated to help plan the surgical treatment for the patient. The dynamic computed tomography angiography protocol consisted of a first image acquisition with the patient in the anatomic position of the head and neck. This was followed by a second acquisition with the head and neck rotated to the side that triggered the symptoms, with technical parameters similar to the first acquisition. The acquired images were used to print a 3D model to better depict the findings for the surgical team. The dynamic computed tomography angiography protocol developed in this study helped visualize the vertebrobasilar arterial anatomy, detect vertebral artery stenosis produced by head and neck rotation, depict the structure responsible for artery stenosis (e.g., bony structure or membranes), and study possible complications of the disease (e.g., posterior cerebral circulation infarction). Additionally, the 3D-printed model better illustrated the findings of stenosis, aiding in surgical planning. In conclusion, dynamic computed tomography angiography for the evaluation of bow Hunter's syndrome is a feasible noninvasive technique that can be used as an alternative to traditional diagnostic methods.

Diffuse large B-cell lymphoma of the central nervous system presenting as "lymphomatosis cerebri" and dementia in elderly man: Case report and review of the literature.

RATIONALE: Lymphomatosis cerebri is a rare form of PCNSL, characterized by diffuse infiltration of lymphoma cells in cerebral parenchyma, without mass-formation and mild or no contrast enhancement on magnetic resonance (MR) imaging. There are less than 50 cases described in the literature under the term Lymphomatosis cerebri. PATIENT CONCERNS: A 74-year-old man presented to our service with progressive dementia for 12 months and accelerated cognitive decline within the last two months. Brain magnetic resonance imaging showed areas of hyperintensity involving predominantly the white matter of frontal lobes and knee of the corpus callosum, along with areas of blood-brain barrier disruption and areas of restricted diffusion. Stereotaxy brain surgery was indicated into contrasting areas and histologically there was heterogeneous foci of discreet infiltration of rare medium-large lymphoid cells intermingled with inflammatory cells and these atypical lymphoid cells were placed on breakdown neuropil and did not form tumor mass or sheets of cells, but occasionally displayed perivascular distribution. Immunohistochemically, these atypical lymphoid cells expressed CD20, Bcl2, Bcl6 and, heterogeneously, IRF4/MUM1. DIAGNOSIS: The diagnosis of a primary CNS diffuse large B-cell lymphoma manifested as lymphomatosis cerebri was performed. INTERVENTIONS: The treatment of choice was: temozolomide 100 mg/m (D1 to D5), methotrexate 3 g/m (D1, D10, and D20) and rituximab 375 mg/m. OUTCOMES: The patient evolved with progressive neurological deterioration, regardless of the improvement on neuroimaging. LESSONS: We described the diagnostic dilemma we faced with an elderly man with rapid cognitive impairment and a myriad of differential diagnoses, diagnosed with primary CNS diffuse large B-cell lymphoma with a lymphomatosis cerebri-like pattern.