Mild phenotype in a male with pyruvate dehydrogenase complex deficiency associated with novel hemizygous in-frame duplication of the E1α subunit gene (PDHA1).

Pyruvate dehydrogenase complex (PDHC) deficiency is an inborn error of metabolism that occurs most commonly due to mutations in the X-linked E1α subunit gene (PDHA1). We report a novel duplication of PDHA1 associated with a mild phenotype in a 15-year-old boy who was diagnosed with PDHC deficiency at 4 years of age following a history of seizures and lactic acidosis. The novel c.1087_1119 mutation in exon 11 resulted in an in-frame duplication of 11 amino acids. Measurements of PDHC activity in cultured skin fibroblasts were low, corresponding to 18.6 and 11.6% of the mean with respect to prior controls, whereas the E1 PDH component was absent. He has borderline intellectual functioning and maintains normal lactate levels on a ketogenic diet in between relapses due to illness. Review of the literature reveals wide variation of clinical phenotype in patients with mutations of the E1α subunit gene (PDHA1). There appears to be a higher incidence of normal or borderline intellectual ability in individuals who have insertions or deletions that are in-frame versus those that are out-of-frame. Furthermore, there is no correlation between mean residual PDH activity and phenotype in these patients.

Neuroimaging findings of the post-treatment effects of radiation and chemotherapy of malignant primary glial neoplasms.

Post-treatment radiation and chemotherapy of malignant primary glial neoplasms present a wide spectrum of tumor appearances and treatment-related entities. Radiologic findings of these post-treatment effects overlap, making it difficult to distinguish treatment response and failure. The purposes of this article are to illustrate and contrast the imaging appearances of recurrent tumor from necrosis and to discuss other radiologic effects of cancer treatments. It is critical for radiologists to recognize these treatment-related effects to help direct clinical management.

Retrospective review of cerebral mycotic aneurysms in 26 patients: focus on treatment in strongly immunocompromised patients with a brief literature review.

BACKGROUND AND PURPOSE: Cerebral mycotic aneurysms are a rare and deadly type of aneurysm that have no definitive treatment guidelines. Our purpose was to retrospectively review known or suspected cases of CMA in order to identify patient populations that may be associated with higher morbidity and mortality. We hope that the identification of patients with these risk factors will lead to early stratification upon presentation, and more urgent treatment of their CMAs. We also hoped to identify any benefit or complication that was specific to either the endovascular or neurosurgical repair of CMAs. MATERIALS AND METHODS: A retrospective multi-institutional study was performed examining cases of CMA during a 15-year period. Patients were considered strongly immunocompromised if there were long-term severely immunocompromised states: AIDS, chemotherapy, or steroid immunosuppression. Patients were excluded if angiographic findings suggested an alternative diagnosis or if an infectious etiology was unknown. Antibiotics were considered "noninvasive treatment." Endovascular and neurosurgical repair were considered "invasive treatment." Data were recorded by reviewing electronic medical records and imaging reports. RESULTS: Twenty-six patients with 40 CMAs were included. Three patients were considered strongly immunocompromised and presented with 4 CMAs, which demonstrated larger average size and more rapid growth; 3 of these patients' aneurysms were treated invasively in the acute period, with the one that was not ruptured causing death. Technical success (aneurysm occlusion without rupture or recanalization) and clinical success (no neurologic complication attributable to the intervention) were obtained equally endovascularly and neurosurgically. Clipping was aborted in favor of coiling for 1 patient. Anticoagulation needed reversal before 2 patients underwent craniotomy for clipping after valve replacement. For CMAs treated with antibiotics alone with angiographic follow-up (n=11), initial aneurysm size was unrelated to persistence and 64% completely regressed. CONCLUSIONS: We recommend initial invasive treatment for CMAs in strongly immunocompromised patients. Testing for underlying immunocompromised states is warranted in patients with CMAs. Endovascular treatment is favored over neurosurgical treatment in patients requiring acute cardiac valve repair due to delays with anticoagulation reversal.

Cerebral thromboembolism: value of susceptibility-weighted imaging in the initial diagnosis of acute infarction.

Susceptibility-weighted imaging (SWI) is commonly used to diagnose cerebral hemorrhage, calcification, and other T2* lesions. Its role in the detection of cerebral thromboemboli has been suggested for emboli of the anterior division of the middle cerebral artery (MCA). The purpose of our study was to determine SWI's accuracy and sensitivity in detection of all sites of cerebral thromboemboli, not just MCA emboli. Two neuroradiologists retrospectively reviewed consecutive MRI brain examinations with SWI for cerebral thromboemboli in 100 patients with clinical suspicion for stroke determined by the NIH Stroke Scale (NIHSS) score. FLAIR, MRA, CT, and catheter angiography were reviewed for thromboemboli in the same patients. Thromboembolic sites included: the internal carotid artery (ICA) terminus, anterior MCA, posterior MCA, any other cerebral artery, or if not present. The exclusion criteria included: no magnetic resonance angiogram (MRA) or catheter angiogram for comparison, lack of restricted diffusion, lacunar infarcts, and the presence of massive hemorrhage. The accuracy, sensitivity, and specificity of each imaging modality were determined. Twenty-four patients were excluded based on the aforementioned criteria. Cerebral thromboemboli were identified in 35 of the remaining 76 patients. Of the 35 patients with thromboemboli, 30 were identified on SWI. FLAIR detected 22/35 emboli, MRA 30/33, CT 18/35, and catheter angiography 12/12. The accuracies for SWI, FLAIR, and CT were 97%, 84%, and 74%, respectively. The sensitivities for SWI, FLAIR, and CT were 85%, 61%, and 52%, respectively. The specificities for SWI, FLAIR, and CT were 100%, 98%, and 93%, respectively. There is an adjunctive role of SWI to identify cerebral thromboemboli in patients with acute infarction. SWI is superior to FLAIR and CT, and complementary to MRA and catheter angiography in emboli detection. This study supports SWI detection of MCA emboli, but also emphasizes its utility in emboli detection of other arteries based on a high accuracy and sensitivity.

Susceptibility weighted imaging and cerebrovascular disorders.

To investigate the correlation between the SWI findings and prognosis of the cerebrovascular disorders. From July 2008 to July 2010, 299 ischemic stroke patients were found in our hospital. The gender ratio is as male and female being 157 to 142. The mean age of all patients is 65.4, mean female age is 69.1, and mean male age is 62.6. There were 86 patients who had satisfactory pre-and post-treatment of CT, MRI with SWI. 23 of these 86 patients had catheter cerebral angiography. 50 of these 86 patients had MR angiogram or CT angiogram. 13 of these 86 patients did not have angiogram. We have also collected 7 severe cardiac arrested and cessation of cerebral circulation and 2 patients with chronic venous hypertension. Among the 86 patients, 23 patients who had negative with deoxygenated vessel on SWI were with small infarction on DWI. Thirty-one patients had negative on initial CT head scan. CT finding did not accord with presence of hypointense vessel on SWI. Sixty-three patients had varied degree of abnormal hypointense vessels on SWI as deoxygenated vessels. The initial small foci on DWI may result with a larger infarction if there were with prominent hypointense vessels.

Assessment of the Correlation between Apparent Diffusion Coefficient and Intervertebral Disk Degeneration Using 3 Tesla MRI.

The objective is to use DW-MR imaging using 3 Tesla MRI to assess the correlation between the mean ADC with degenerative disk disease (DDD). We recruited 34 subjects and used DWI-MR to image lumbar intervertebral disks. We acquired a T2W scan and DWIs. The disks were graded for DDD. Assessment of correlation between mean ADC was made. 170 disks were evaluated. The observed sample correlation between mean ADC and disk degeneration was r = 0.65 [0.55-0.73]. The observed sample correlation between mid-sagittal ADC and disk degeneration was r = 0.61 [0.51-0.70]. The differences between mean ADC of each grade were significant, except between grades 4 and 5. There is a correlation of 0.65 between the mean ADC and disk degeneration. This correlation is not strong enough to use the ADC to determine DDD in clinical settings. There was no evident difference in ADC between the studied anatomic lumbar levels.

Toward a uniform policy for handling incidental findings in neuroimaging research.

A recent study carried out at the University of California, Irvine exemplifies a commonly overlooked ethical conundrum of neuroimaging research: incidental findings. Research study designs must address the potential of uncovering unexpected findings in subjects during the study and delineate a protocol for reporting and initiating treatment. We urge the community to petition their home institutional review board to mandate inclusion of an incidental findings protocol into all neuroimaging research applications.

Traumatic retropharyngeal pseudomeningocele with atlanto-occipital dislocation in a neurologically intact patient.

Traumatic retropharyngeal pseudomeningoceles occur rarely, are associated with severe trauma, and have been reported in patients with significant neurologic deficits at presentation. We report the rare occurrence of a pseudomeningocele following a high-speed motor vehicle accident. Neurological examination showed the patient to be briskly following commands, with intact cranial nerve, motor, and sensory function. CT/MR imaging showed subarachnoid hemorrhage involving the interpeduncular cistern, a clivus fracture, a right occipital condyle fracture, an atlanto-occipital subluxation, aortic arch transection (stable and contained on CT angiogram), multiple rib fractures on the right side with associated pneumothorax, hemothorax and pulmonary contusions. His cervical spine was stabilized in a halo. He was subsequently managed in the intensive care unit and remained neurologically intact. A repeat MRI showed the interval development of a 2×1.5 cm pseudomeningocele at the craniocervical junction medial to the left occipital condyle communicating with the left anterolateral aspect of the spinal canal. Traumatic pseudomeningoceles are associated with large deceleration forces at the time of injury and are usually associated with significant neurologic deficits at presentation. However, they can arise and give rise to symptoms in a delayed fashion in trauma patients who are neurologically intact at initial presentation.

Pituicytoma: diagnostic features on selective carotid angiography and MR imaging.

We report a case of pituicytoma, a rare primary tumor of the neurohypophysis. A 64-year-old man presented with progressive visual complaints, bitemporal hemianopsia, and headache. Imaging studies revealed distinctive features of a mass lesion that thickened the pituitary stalk with a bilobed protrusion extending into the hypothalamus. Angiography demonstrated tumor vascular supply from the superior hypophyseal arteries representing the diencephalic branches of the internal carotid arteries. We discuss the imaging and pathology of this unusual tumor.

Imaging of craniofacial and sinonasal anomalies.

Whereas CT imaging techniques such as multiple detector spiral imaging with multi-planar reconstructions are desirable in the evaluation of congenital and developmental anomalies of the midface and skull base, there is an essential role for MRI whenever there are related intracranial anomalies. This presentation will focus on describing and classifying the known craniofacial anomalies that have common manifestations in the sinonasal regions, the orbits, and the skull base. Diagrams and clinical cases are utilized to demonstrate the key embryological events leading to the common dysplasias of the craniofacial and sinonasal regions.