Intrakranielle Läsionen hoher Signalintensität in T1-gewichteten MRT-Aufnahmen: Differenzialdiagnose^[1]

Zusammenfassung

Verschiedene Substanzen, wie Methämoglobin, Melanin, Lipide, Proteine, Kalzium, Eisen, Kupfer und Mangan sind für die intrinsische hohe Signalintensität verantwortlich, die intrakranielle Läsionen in der T1-gewichteten Magnetresonanztomografie zeigen. Viele dieser Stoffe haben physikalische Eigenschaften, die zu weiteren spezifischen Merkmalen in der Bildgebung führen. So erzeugen lipidhaltige Läsionen häufig ein Chemical-Shift-Artefakt, und manche melaninhaltigen Läsionen zeigen gleichzeitig eine hohe Signalintensität in T1-gewichteten Aufnahmen und eine geringe Signalintensität in T2-gewichteten Aufnahmen. Lage und Ausdehnung einer Region anomaler Signalhyperintensität können hilfreiche Hinweise zur Identifizierung seltener Erkrankungen liefern. Beispiele dafür sind ein ektopischer Hypophysenhinterlappen in der Nähe des Bodens des III. Ventrikels, die bilaterale Beteiligung des Nucleus dentatus cerebelli und des Nucleus lenticularis beim Cockayne-Syndrom sowie die Beteiligung des anterioren Schläfenlappens und des Zerebellums bei der neurokutanen Melanose. In Fällen, in denen diagnostisch spezifische Merkmale in der T1-gewichteten Bildgebung fehlen, können Befunde aus anderen Pulssequenzen der Magnetresonanztomografie und anderen Modalitäten die Differenzialdiagnose einengen: Ein erhöhter Glutamin- oder Glutamatspiegel in der Magnetresonanzspektroskopie spricht für eine Leberenzephalopathie, ein popkornähnliches Erscheinungsbild in der T2-gewichteten Bildgebung für ein Kavernom und eine hyperdense Erscheinung in der Computertomografie für eine krankheitsbedingte Mineralablagerung. In vielen Fällen ermöglicht der Vergleich der Merkmale in der Bildgebung mit klinischen Parametern eine spezifische Diagnose.

Abstract

Various substances, including methemoglobin, melanin, lipid, protein, calcium, iron, copper, and manganese, are responsible for the intrinsically high signal intensity observed in intracranial lesions at T1-weighted magnetic resonance imaging. Many of these substances have physical properties that lead to other specific imaging features as well. For example, lipid-containing lesions frequently produce chemical shift artifact, and some melanin-containing lesions exhibit a combination of high signal intensity on T1-weighted images and low signal intensity on T2-weighted images. The location and extent of a region of abnormal signal hyperintensity may be helpful for identifying rare diseases such as an ectopic posterior pituitary gland near the floor of the third ventricle, bilateral involvement of the dentate and lentiform nuclei in Cockayne syndrome, and involvement of the anterior temporal lobe and cerebellum in neurocutaneous melanosis. In cases in which diagnostically specific T1-weighted imaging features are lacking, findings obtained with other magnetic resonance pulse sequences and other modalities can help narrow the differential diagnosis: An elevated glutamine or glutamate level at magnetic resonance spectroscopy is suggestive of hepatic encephalopathy; a popcorn ball-like appearance at T2-weighted imaging, of cavernous malformations; and hyperattenuation at computed tomography, of mineral deposition disease. In many cases, a comparison of imaging features with clinical measures enables a specific diagnosis.

• Literatur

• 1 Jacobs MA, Ibrahim TS, Ouwerkerk R. MR imaging: brief overview and emerging applications. RadioGraphics 2007; 27 : 1213-1229
• 2 Bitar R, Leung G, Perng R et al. MR pulse sequences: what every radiologist wants to know but is afraid to ask. RadioGraphics 2006; 26: 513-537
• 3 Takahashi M, Uematsu H, Hatabu H. MR imaging at high magnetic fields. Eur J Radiol 2003; 46: 45-52
• 4 Maubon AJ, Ferru JM, Berger V et al. Effect of field strength on MR images: comparison of the same subject at 0.5, 1.0, and 1.5 T. RadioGraphics 1999; 19: 1057-1067
• 5 Bradley Jr WG. MR appearance of hemorrhage in the brain. Radiology 1993; 189: 15-26
• 6 Chao CP, Kotsenas AL, Broderick DF. Cerebral amyloid angiopathy: CT and MR imaging findings. RadioGraphics 2006; 26: 1517-1531
• 7 Knudsen KA, Rosand J, Karluk D et al. Clinical diagnosis of cerebral amyloid angiopathy: validation of the Boston criteria. Neurology 2001; 56: 537-539
• 8 Zabramski JM, Wascher TM, Spetzler RF et al. The natural history of familial cavernous malformations: results of an ongoing study. J Neurosurg 1994; 80: 422-432
• 9 Yun TJ, Na DG, Kwon BJ et al. A T1 hyperintense perilesional signal aids in the differentiation of a cavernous angioma from other hemorrhagic masses. AJNR Am J Neuroradiol 2008; 29: 494-500
• 10 Petersen TA, Morrison LA, Schrader RM et al. Familial versus sporadic cavernous malformations: differences in developmental venous anomaly association and lesion phenotype. AJNR Am J Neuroradiol 2010; 31: 377-382
• 11 Isensee C, Reul J, Thron A. Magnetic resonance imaging of thrombosed dural sinuses. Stroke 1994; 25: 29-34
• 12 Poon CS, Chang JK, Swarnkar A et al. Radiologic diagnosis of cerebral venous thrombosis: pictorial review. AJR Am J Roentgenol 2007; 189: 64-S75
• 13 Isiklar I, Leeds NE, Fuller GN et al. Intracranial metastatic melanoma: correlation between MR imaging characteristics and melanin content. AJR Am J Roentgenol 1995; 165: 1503-1512
• 14 Enochs WS, Petherick P, Bogdanova A et al. Paramagnetic metal scavenging by melanin: MR imaging. Radiology 1997; 204: 417-423
• 15 Leach JL, Fortuna RB, Jones BV et al. Imaging of cerebral venous thrombosis: current techniques, spectrum of findings, and diagnostic pitfalls. RadioGraphics 2006; 26: 19-41 ; discussion S42–S43
• 16 Escott EJ. A variety of appearances of malignant melanoma in the head: a review. RadioGraphics 2001; 21: 625-639
• 17 Liubinas SV, Maartens N, Drummond KJ. Primary melanocytic neoplasms of the central nervous system. J Clin Neurosci 2010; 17: 1227-1232
• 18 Smith AB, Rushing EJ, Smirniotopoulos JG. Pigmented lesions of the central nervous system: radiologic-pathologic correlation. RadioGraphics 2009; 29: 1503-1524
• 19 Pirini MG, Mascalchi M, Salvi F et al. Primary diffuse meningeal melanomatosis: radiologic-pathologic correlation. AJNR Am J Neuroradiol 2003; 24: 115-118
• 20 Henkelman RM, Watts JF, Kucharczyk W. High signal intensity in MR images of calcified brain tissue. Radiology 1991; 179: 199-206
• 21 Warakaulle DR, Anslow P. Differential diagnosis of intracranial lesions with high signal on T1 or low signal on T2-weighted MRI. Clin Radiol 2003; 58: 922-933
• 22 Hood MN, Ho VB, Smirniotopoulos JG et al. Chemical shift: the artifact and clinical tool revisited. RadioGraphics 1999; 19: 357-371
• 23 Truwit CL, Barkovich AJ. Pathogenesis of intracranial lipoma: an MR study in 42 patients. AJR Am J Roentgenol 1990; 155: 855-864 ; discussion 865
• 24 Jabot G, Stoquart-Elsankari S, Saliou G et al. Intracranial lipomas: clinical appearances on neuroimaging and clinical significance. J Neurol 2009; 256: 851-855
• 25 Yildiz H, Hakyemez B, Koroglu M et al. Intracranial lipomas: importance of localization. Neuroradiology 2006; 48: 1-7
• 26 Smirniotopoulos JG, Chiechi MV. Teratomas, dermoids, and epidermoids of the head and neck. RadioGraphics 1995; 15: 1437-1455
• 27 Isaacs Jr H. I. Perinatal brain tumors: a review of 250 cases. Pediatr Neurol 2002; 27: 249-261
• 28 Liu JK, Gottfried ON, Salzman KL et al. Ruptured intracranial dermoid cysts: clinical, radiographic, and surgical features. Neurosurgery 2008; 62: 377-384 ; discussion 384
• 29 Osborn AG, Preece MT. Intracranial cysts: radiologic-pathologic correlation and imaging approach. Radiology 2006; 239: 650-664
• 30 Stendel R, Pietilä TA, Lehmann K et al. Ruptured intracranial dermoid cysts. Surg Neurol 2002; 57: 391-398 ; discussion 398
• 31 Ruchoux MM, Kepes JJ, Dhellemmes P et al. Lipomatous differentiation in ependymomas: a report of three cases and comparison with similar changes reported in other central nervous system neoplasms of neuroectodermal origin. Am J Surg Pathol 1998; 22: 338-346
• 32 Chang WE, Finn LS. MR appearance of lipomatous ependymoma in a 5-year-old boy. AJR Am J Roentgenol 2001; 177: 1475-1478
• 33 Fullerton GD, Finnie MF, Hunter KE et al. The influence of macromolecular polymerization of spin-lattice relaxation of aqueous solutions. Magn Reson Imaging 1987; 5: 353-370
• 34 Som PM, Dillon WP, Fullerton GD et al. Chronically obstructed sinonasal secretions: observations on T1 and T2 shortening. Radiology 1989; 172: 515-520
• 35 Armao D, Castillo M, Chen H et al. Colloid cyst of the third ventricle: imaging-pathologic correlation. AJNR Am J Neuroradiol 2000; 21: 1470-1477
• 36 Sumida M, Uozumi T, Mukada K et al. Rathke cleft cysts: correlation of enhanced MR and surgical findings. AJNR Am J Neuroradiol 1994; 15: 525-532
• 37 Binning MJ, Gottfried ON, Osborn AG et al. Rathke cleft cyst intracystic nodule: a characteristic magnetic resonance imaging finding. J Neurosurg 2005; 103: 837-840
• 38 Kim JE, Kim JH, Kim OL et al. Surgical treatment of symptomatic Rathke cleft cysts: clinical features and results with special attention to recurrence. J Neurosurg 2004; 100: 33-40
• 39 Mitchell LA, Thomas PQ, Zacharin MR et al. Ectopic posterior pituitary lobe and periventricular heterotopia: cerebral malformations with the same underlying mechanism?. AJNR Am J Neuroradiol 2002; 23: 1475-1481
• 40 van der Linden AS, van Es HW. Case 112: pituitary stalk transection syndrome with ectopic posterior pituitary gland. Radiology 2007; 243: 594-597
• 41 Fujisawa I, Kikuchi K, Nishimura K et al. Transection of the pituitary stalk: development of an ectopic posterior lobe assessed with MR imaging. Radiology 1987; 165: 487-489
• 42 Castillo M. Pituitary gland: development, normal appearances, and magnetic resonance imaging protocols. Top Magn Reson Imaging 2005; 16: 259-268
• 43 Kurokawa H, Fujisawa I, Nakano Y et al. Posterior lobe of the pituitary gland: correlation between signal intensity on T1-weighted MR images and vasopressin concentration. Radiology 1998; 207: 79-83
• 44 Koob M, Laugel V, Durand M et al. Neuroimaging in Cockayne syndrome. AJNR Am J Neuroradiol 2010; 31: 1623-1630
• 45 McNeill A, Chinnery PF. Neurodegeneration with brain iron accumulation. Handb Clin Neurol 2011; 100: 161-172
• 46 Sener RN. Pantothenate kinase-associated neuro­degeneration: MR imaging, proton MR spectroscopy, and diffusion MR imaging findings. AJNR Am J Neuroradiol 2003; 24: 1690-1693
• 47 Hayflick SJ, Hartman M, Coryell J et al. Brain MRI in neurodegeneration with brain iron accumulation with and without PANK2 mutations. AJNR Am J Neuroradiol 2006; 27: 1230-1233
• 48 Rovira A, Alonso J, Córdoba J. MR imaging findings in hepatic encephalopathy. AJNR Am J Neuroradiol 2008; 29: 1612-1621
• 49 Pujol A, Pujol J, Graus F et al. Hyperintense globus pallidus on T1-weighted MRI in cirrhotic patients is associated with severity of liver failure. Neurology 1993; 43: 65-69
• 50 Pujol J, Kulisevsky J, Moreno A et al. Neurospectroscopic alterations and globus pallidus hyperintensity as related magnetic resonance markers of reversible hepatic encephalopathy. Neurology 1996; 47: 1526-1530
• 51 Lorincz MT. Neurologic Wilson’s disease. Ann N Y Acad Sci 2010; 1184: 173-187
• 52 van Wassenaer-van Hall HN, van den Heuvel AG, Algra A et al. Wilson disease: findings at MR imaging and CT of the brain with clinical correlation. Radiology 1996; 198: 531-536
• 53 Kim TJ, Kim IO, Kim WS et al. MR imaging of the brain in Wilson disease of childhood: findings before and after treatment with clinical correlation. AJNR Am J Neuroradiol 2006; 27: 1373-1378
• 54 Thapa R, Ghosh A. ‘Face of the giant panda’ sign in Wilson disease. Pediatr Radiol 2008; 38: 1355
• 55 Williams VC, Lucas J, Babcock MA et al. Neurofibromatosis type 1 revisited. Pediatrics 2009; 123: 124-133
• 56 Jacques C, Dietemann JL. Imaging features of neurofibromatosis type 1 [in French]. J Neuroradiol 2005; 32: 180-197
• 57 Terada H, Barkovich AJ, Edwards MS et al. Evolution of high-intensity basal ganglia lesions on T1-weighted MR in neurofibromatosis type 1. AJNR Am J Neuroradiol 1996; 17: 755-760
• 58 Mirowitz SA, Sartor K, Gado M. High-intensity basal ganglia lesions on T1-weighted MR images in neurofibromatosis. AJR Am J Roentgenol 1990; 154: 369-373
• 59 DiPaolo DP, Zimmerman RA, Rorke LB et al. Neurofibromatosis type 1: pathologic substrate of high-signal-intensity foci in the brain. Radiology 1995; 195: 721-724
• 60 Royer MC, Pensak ML. Cholesterol granulomas. Curr Opin Otolaryngol Head Neck Surg 2007; 15: 319-322
• 61 Chapman PR, Shah R, Curé JK et al. Petrous apex lesions: pictorial review. AJR Am J Roentgenol 2011; 196: WS26-WS37
• 62 Chow LP, McNab AA. Orbitofrontal cholesterol granuloma. J Clin Neurosci 2005; 12: 206-209
• 63 Thedinger BA, Nadol Jr JB, Montgomery WW et al. Radiographic diagnosis, surgical treatment, and long-term follow-up of cholesterol granulomas of the petrous apex. Laryngoscope 1989; 99: 896-907
• 64 Greenberg JJ, Oot RF, Wismer GL et al. Cholesterol granuloma of the petrous apex: MR and CT evaluation. AJNR Am J Neuroradiol 1988; 9: 1205-1214
• 65 Prabhu VC, Brown HG. The pathogenesis of craniopharyngiomas. Childs Nerv Syst 2005; 21: 622-627
• 66 Zada G, Lin N, Ojerholm E et al. Craniopharyngioma and other cystic epithelial lesions of the sellar region: a review of clinical, imaging, and histopathological relationships. Neurosurg Focus 2010; 28: E4
• 67 Curran JG, O’Connor E. Imaging of craniopharyngioma. Childs Nerv Syst 2005; 21: 635-639
• 68 Ahmadi J, Destian S, Apuzzo ML et al. Cystic fluid in craniopharyngiomas: MR imaging and quantitative analysis. Radiology 1992; 182: 783-785
• 69 Bargalló N, Burrel M, Berenguer J et al. Cortical laminar necrosis caused by immunosuppressive therapy and chemotherapy. AJNR Am J Neuroradiol 2000; 21: 479-484
• 70 Kuroiwa T, Okeda R. Neuropathology of cerebral ischemia and hypoxia: recent advances in experimental studies on its pathogenesis. Pathol Int 1994; 44: 171-181
• 71 Siskas N, Lefkopoulos A, Ioannidis I et al. Cortical laminar necrosis in brain infarcts: serial MRI. Neuroradiology 2003; 45: 283-288
• 72 Shan DE. Delayed ischemic hyperintensity of T1-weighted MRI. Stroke 2000; 31: 797-798
• 73 Niwa T, Aida N, Shishikura A et al. Susceptibility-weighted imaging findings of cortical laminar necrosis in pediatric patients. AJNR Am J Neuroradiol 2008; 29: 1795-1798