Acute neurological deficit with submassive pulmonary emboli.

Pulmonary embolism (PE) is frequently encountered in the emergency department. Syncope, often as a consequence of impending haemodynamic collapse, is associated with increased mortality. While loss of consciousness owing to cerebral hypoperfusion and reduced left ventricular preload is a common cause of collapse with large volume PE, other syndromes can also cause neurological deficit in thromboembolic disease. Here, we describe a case of a woman in her 60s, presenting to the emergency department with features of high-risk PE. During clinical examination, the patient collapsed and became unresponsive with a Glasgow Coma Scale of 4/15 despite normal haemodynamics. Neurological signs were noted and CT revealed evidence of a large territory cerebral infarction. Further cardiovascular investigations identified a grade 4 patent foramen ovale. We describe a challenging case of established venous thromboembolism complicated by paradoxical embolism, highlighting the importance of thorough clinical examination and investigation and discuss the current evidence base of treatments.

Further delineation of pontocerebellar hypoplasia type 6 due to mutations in the gene encoding mitochondrial arginyl-tRNA synthetase, RARS2.

Pontocerebellar hypoplasia type 6 (PCH6) (MIM #611523) is a recently described disorder caused by mutations in RARS2 (MIM *611524), the gene encoding mitochondrial arginyl-transfer RNA (tRNA) synthetase, a protein essential for translation of all mitochondrially synthesised proteins. This case confirms that progressive cerebellar and cerebral atrophy with microcephaly and complex epilepsy are characteristic features of PCH6. Additional features of PCH subtypes 2 and 4, including severe dystonia, optic atrophy and thinning of the corpus callosum, are demonstrated. Congenital lactic acidosis can be present, but respiratory chain dysfunction may be mild or absent, suggesting that disordered mitochondrial messenger RNA (mRNA) translation may not be the only mechanism of impairment or that a secondary mechanism exists to allow some translation. We report two novel mutations and expand the phenotypic spectrum of this likely underdiagnosed PCH variant, where recognition of the characteristic neuroradiological phenotype could potentially expedite genetic diagnosis and limit invasive investigations.

123I-metaiodobenzylguanidine (MIBG) scintigraphy for the detection of adrenal and extra-adrenal phaeochromocytomas: CT and MRI correlation.

CONTEXT: Evidence regarding the accuracy of [(123)I] metaiodobenzylguanidine (MIBG) imaging for phaeochromocytoma localization is currently limited to small series. OBJECTIVE: We present the largest series of primary phaeochromocytomas in which the performance of [(123)I]MIBG has been evaluated and correlated with cross-sectional imaging. DESIGN: We identified 76 patients with both preoperative [(123)I]MIBG and cross-sectional imaging for confirmed primary phaeochromocytoma between 1995 and 2005 at our institution. This comprised 60 adrenal tumours in 55 patients and 33 extra-adrenal tumours in 23 patients (2 patients had both adrenal and extra-adrenal tumours). Phaeochromocytoma metastases were not evaluated. MAIN OUTCOME MEASURE(S): [(123)I]MIBG studies were independently reviewed and correlated with CT and MRI examinations, as well as tumour functional status, to identify features that may predict a false negative [(123)I]MIBG result. RESULTS: The overall sensitivity of [(123)I]MIBG was 75%. Tumour detection was lower for extra-adrenal (58%) vs. adrenal (85%) phaeochromocytomas (P = 0.005). For extra-adrenal tumours, [(123)I]MIBG demonstrated 8 of 14 carotid body, 2 of 2 intrathoracic, 8 of 14 retroperitoneal and 2 of 3 pelvic phaeochromocytomas. Overall, MRI and CT demonstrated 68 of 68 and 72 of 74 primary phaeochromocytomas, respectively. Tumour size correlated with [(123)I]MIBG uptake for adrenal (P = 0.009) but not extra-adrenal tumours. When tumours were adjusted for size, no other imaging feature or functional status correlated with [(123)I]MIBG negativity, although two large [(123)I]MIBG negative adrenal tumours contained large areas of necrosis or haemorrhage. CONCLUSIONS: Extra-adrenal and small adrenal phaeochromocytomas are more likely to result in false negatives on [(123)I]MIBG. Tumoural necrosis or haemorrhage do not consistently relate to [(123)I]MIBG uptake, although adrenal phaeochromocytomas containing minimal solid tissue due to extensive necrosis may predict a negative [(123)I]MIBG result.