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Choroid Plexus Papilloma

Editor: Joe M Das Updated: 6/5/2022 11:33:01 PM

Introduction

Choroid plexus papillomas (CPPs) are rare central nervous system tumors. They may be seen at any age, but are more common in infants. Their site of occurrence varies according to age. They usually present with the increasing head circumference or altered mental status in children; whereas in adults they present with signs of increased intracranial tension. Imaging shows intraventricular enhancing masses. Surgery is the therapeutic intervention of choice for these lesions. They have a good prognosis in spite of their size as they are benign. Improvements in surgical techniques and intensive care have improved survival.

Etiology

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Etiology

Studies have shown that Simian virus (SV) 40 has an association with the occurrence of choroid plexus tumors (CPTs).[1] BK virus and John Cunningham (JC) viruses have also been implicated.[2] The binding of the large T antigen with both p53 and pRb tumor suppressor proteins, forming complexes, has been demonstrated in humans harboring choroid plexus tumors.[2] Current data do not, however, support a causative role. No other causative factor is presently under research.

R248W mutation of the TP53 gene is one of the most common mutations in CPTs.[3]

Epidemiology

CPPs are rare tumors of neuroectodermal origin. In the pediatric population, they form the third most common congenital brain tumors, after teratomas and gliomas, and account for 0.4 to 0.6% of all intracranial neoplasms.[4] This lesion is generally a disease of childhood, with a median age at diagnosis of 3.5 years. Typically in infants, their location is supratentorial, within the lateral ventricles (most commonly in the atrium).[5] In adults, the preferred site is the fourth ventricle.[6] The cerebellopontine angle is a rare location in adults.[6]

Pathophysiology

According to the World Health Organization classification (2016),[7] choroid plexus tumors are classified as papillomas (grade I), atypical tumors (grade II), and carcinomas (grade III). CPPs have less than two mitotic figures per 10 high power fields, atypical ones have two to five per 10 high power fields, and carcinomas have greater than five mitotic figures per 10 high power fields. Grossly, the tumors are soft, globular, friable pink masses with irregular projections and high vascularity.

Histopathology

Microscopy shows papillary fronds lined by bland columnar epithelium. Mitotic activity, nuclear pleomorphism, and necrosis are typically absent.[8]

On immunohistochemistry, tumors are positive for cytokeratin, vimentin, podoplanin, and S-100.[9][8] Glial fibrillary acidic protein (GFAP) may be positive in up to 20% of cases of choroid plexus papilloma.[10] Studies have shown that older patients (above 20 years) express more GFAP and transthyretin than younger patients and fourth ventricle tumors express more S100 than lateral ventricle tumors.[11]

Genetic analyses have reported germline mutations in the TP53 gene in some patients with choroid plexus papilloma.[12] Rarely these tumors show positive nuclear staining for p53 protein. Syndromic associations of choroid plexus papilloma include Aicardi syndrome, hypomelanosis of Ito, and 9p duplication.

Feature of atypical choroid plexus papilloma:

The presence of more than 2 mitoses in the high-power field

Features suggestive of choroid plexus carcinoma:

The presence of any four of the following malignant characteristics:

  1. Brisk mitotic activity (> 5 mitoses per 10 high-power fields)
  2. Nuclear pleomorphism
  3. High cellularity
  4. The blurring of the papillary growth pattern and
  5. Necrosis

DNA methylation profiling has shown three distinct and molecular subgroups for CPTs[13]:

  1. Supratentorial pediatric low-risk choroid plexus tumors (CPP and aCPP)
  2. Infratentorial adult low-risk choroid plexus tumors (CPP and aCPP) and
  3. Supratentorial pediatric high-risk choroid plexus tumors (CPP and aCPP and CPC).

History and Physical

Patients typically present with a history of gradual deterioration. Signs of raised intracranial tension, like vomiting, headache, lateral gaze palsies, homonymous visual field defects, reduced mentation, and so on are usually evident. Sometimes the patient may develop subarachnoid hemorrhage due to bleeding from the tumor. Infants present with increasing head circumference or poor feeding or both, along with upgaze palsy, reduced activity, and altered consciousness.

The clinical symptoms are predominantly due to hydrocephalus[14], as a result of direct mechanical obstruction to the flow of cerebrospinal fluid (CSF) due to an arachnoid granulation blockage from hemorrhage or CSF overproduction.[15] Though benign, studies exist showing a rapid growth in tumor size.[16] Sometimes, CSF rhinorrhea or hemifacial spasm may be the only clinical presentations.[17][18]

Evaluation

If fontanelles are not fused, neurosonogram (NSG) through the anterior fontanelle will demonstrate an echogenic lesion within the ventricles. This lesion continues to demonstrate bidirectional flow throughout the diastole, indicating blood flow through vessels arranged chaotically. Sometimes, the lesions are diagnosed antenatally by using ultrasound scans.[19]

Computerized tomography (CT) shows an isodense or slightly hyperdense lesion within the ventricles along with consequent ventriculomegaly.[20] Hydrocephalus is typical. About 25% of the patients have calcification. The lesions are lobulated with slightly irregular margins. They also show intense and somewhat heterogeneous contrast enhancement. Angiographic and cross-sectional imaging show enlargement of the choroidal artery.

Magnetic resonance imaging (MRI) reveals the well–defined, frond-like intraventricular lobulated masses, which are hypointense on T1WI  and hyperintense on T2WI.[21] Flow voids are seen, indicating active blood flow. The lesions are brilliantly enhancing, owing to rich vascularity. There are recent studies with the use of arterial spin labeling that can help distinguish choroid plexus papilloma from choroid plexus carcinoma.[22]

Treatment / Management

In incidentally detected tumors, there is controversy regarding the timing of surgery.[23] Prompt surgical removal may be one option, or surgery may be withheld until follow-up imaging shows radiographic changes or hydrocephalus, or surgery may be an option once the patient becomes symptomatic. Once hydrocephalus develops it is easier to resect the tumor, as the length of the corridor to the ventricles reduces, and space around the tumor increases.  The disadvantage of such a policy is that patients may develop focal deficits from mass effect, subarachnoid hemorrhage, or seizures. Also, as tumors grow patients tend to develop cognitive defects.[24]

In symptomatic patients, gross total resection (GTR) is the treatment of choice as these tumors are benign. Recent advances in imaging, surgical approaches, and quality of intensive care have improved surgical outcomes with the chances of a cure reaching almost 100%.[5] In the pediatric population, there is significant (12%) perioperative mortality, mainly from catastrophic blood loss.[25] Preoperative embolization can minimize this risk, along with optimization of the ability to resect the tumor completely.[26] Radiosurgery may be a possible treatment option, but further studies are required to determine its efficacy.[27] There have also been attempts at percutaneous stereotactic intratumoral embolization with a sclerosing agent, to reduce blood flow and improve tumor resectability.[28](B2)

Adjuvant chemotherapy, though limited in use, can prevent recurrence and prolong survival.[29]  A growing residual choroid plexus papilloma may be treated by irradiation, followed by subtotal resection, providing an even higher chance of success. Adjuvant therapy is also necessary for malignant tumors and those that have shown leptomeningeal spread.[30] Recent studies show an increasing role of bevacizumab in disseminated choroid plexus papilloma.[31](B2)

Differential Diagnosis

Differentials for choroid plexus papilloma include[32]:

  • Intraventricular tumors such as papillary ependymoma
  • Central neurocytoma
  • Subependymal giant cell tumor
  • Subependymoma
  • Choroid plexus tumors
  • Medulloblastoma
  • Meningioma
  • Chordoid glioma
  • Rosette-forming glioneuronal tumor
  • Central nervous system lymphoma
  • Metastasis

Prognosis

Improvements in surgical and intensive care techniques have vastly improved the prognosis of patients.[33] Maximum tumor resection correlates with an increase in both progression-free survival and overall survival.[34] Recurrences are rare. Suprasellar metastases and craniospinal seeding, though rare, have been reported.[35]

Complications

At presentation, children may have features of prolonged raised intracranial pressure such as papilledema, optic atrophy, and visual loss, which may not recover after surgery.[36] Some may develop cognitive defects, bleeding, and seizures that may persist postoperatively.[37][23]

Intraoperatively there are high chances for excessive blood loss due to rich vascularity.[26]

There have also been reports of postoperative CSF rhinorrhoea.[38]

Deterrence and Patient Education

Any child presenting with altered sensorium has to be evaluated for an intraventricular tumor and managed with surgery to improve survival.

Enhancing Healthcare Team Outcomes

Management of choroid plexus papilloma requires an interprofessional team that includes the neurosurgeon, various specialists (e.g., anesthetist, pediatrician, ophthalmologist, neurologist), and neuroscience specialty-trained nurses. It is vital to educate the parents that even though these lesions are benign, complications can occur during surgery. A thorough discussion between the neurosurgeon and family should take place on the optimal procedure for the child. With adequate preparation of the child, the outcomes are excellent.[39]

Media


(Click Image to Enlarge)
Choroid plexus papilloma
Choroid plexus papilloma
Image courtesy S Bhimji MD

References


[1]

Okamoto H, Mineta T, Ueda S, Nakahara Y, Shiraishi T, Tamiya T, Tabuchi K. Detection of JC virus DNA sequences in brain tumors in pediatric patients. Journal of neurosurgery. 2005 Apr:102(3 Suppl):294-8     [PubMed PMID: 15881753]


[2]

Zhen HN, Zhang X, Bu XY, Zhang ZW, Huang WJ, Zhang P, Liang JW, Wang XL. Expression of the simian virus 40 large tumor antigen (Tag) and formation of Tag-p53 and Tag-pRb complexes in human brain tumors. Cancer. 1999 Nov 15:86(10):2124-32     [PubMed PMID: 10570441]


[3]

Yankelevich M, Finlay JL, Gorsi H, Kupsky W, Boue DR, Koschmann CJ, Kumar-Sinha C, Mody R. Molecular insights into malignant progression of atypical choroid plexus papilloma. Cold Spring Harbor molecular case studies. 2021 Feb:7(1):. doi: 10.1101/mcs.a005272. Epub 2021 Feb 19     [PubMed PMID: 33608379]

Level 3 (low-level) evidence

[4]

Bahar M, Hashem H, Tekautz T, Worley S, Tang A, de Blank P, Wolff J. Choroid plexus tumors in adult and pediatric populations: the Cleveland Clinic and University Hospitals experience. Journal of neuro-oncology. 2017 May:132(3):427-432. doi: 10.1007/s11060-017-2384-1. Epub 2017 Mar 13     [PubMed PMID: 28290001]


[5]

Dash C, Moorthy S, Garg K, Singh PK, Kumar A, Gurjar H, Chandra PS, Kale SS. Management of Choroid Plexus Tumors in Infants and Young Children Up to 4 Years of Age: An Institutional Experience. World neurosurgery. 2019 Jan:121():e237-e245. doi: 10.1016/j.wneu.2018.09.089. Epub 2018 Sep 24     [PubMed PMID: 30261376]


[6]

Prasad GL, Mahapatra AK. Case series of choroid plexus papilloma in children at uncommon locations and review of the literature. Surgical neurology international. 2015:6():151. doi: 10.4103/2152-7806.166167. Epub 2015 Sep 28     [PubMed PMID: 26500797]

Level 2 (mid-level) evidence

[7]

Ruggeri L, Alberio N, Alessandrello R, Cinquemani G, Gambadoro C, Lipani R, Maugeri R, Nobile F, Iacopino DG, Urrico G, Battaglia R. Rapid malignant progression of an intraparenchymal choroid plexus papillomas. Surgical neurology international. 2018:9():131. doi: 10.4103/sni.sni_434_17. Epub 2018 Jul 5     [PubMed PMID: 30105129]


[8]

Khade S, Shenoy A. Ectopic Choroid Plexus Papilloma. Asian journal of neurosurgery. 2018 Jan-Mar:13(1):191-194. doi: 10.4103/1793-5482.185067. Epub     [PubMed PMID: 29492159]


[9]

Ikota H, Tanaka Y, Yokoo H, Nakazato Y. Clinicopathological and immunohistochemical study of 20 choroid plexus tumors: their histological diversity and the expression of markers useful for differentiation from metastatic cancer. Brain tumor pathology. 2011 Jul:28(3):215-21. doi: 10.1007/s10014-011-0024-6. Epub 2011 Mar 11     [PubMed PMID: 21394517]


[10]

Prendergast N, Goldstein JD, Beier AD. Choroid plexus adenoma in a child: expanding the clinical and pathological spectrum. Journal of neurosurgery. Pediatrics. 2018 Apr:21(4):428-433. doi: 10.3171/2017.10.PEDS17290. Epub 2018 Feb 2     [PubMed PMID: 29393815]


[11]

Paulus W, Jänisch W. Clinicopathologic correlations in epithelial choroid plexus neoplasms: a study of 52 cases. Acta neuropathologica. 1990:80(6):635-41     [PubMed PMID: 1703384]

Level 3 (low-level) evidence

[12]

Tabori U, Shlien A, Baskin B, Levitt S, Ray P, Alon N, Hawkins C, Bouffet E, Pienkowska M, Lafay-Cousin L, Gozali A, Zhukova N, Shane L, Gonzalez I, Finlay J, Malkin D. TP53 alterations determine clinical subgroups and survival of patients with choroid plexus tumors. Journal of clinical oncology : official journal of the American Society of Clinical Oncology. 2010 Apr 20:28(12):1995-2001. doi: 10.1200/JCO.2009.26.8169. Epub 2010 Mar 22     [PubMed PMID: 20308654]


[13]

Thomas C, Metrock K, Kordes U, Hasselblatt M, Dhall G. Epigenetics impacts upon prognosis and clinical management of choroid plexus tumors. Journal of neuro-oncology. 2020 May:148(1):39-45. doi: 10.1007/s11060-020-03509-5. Epub 2020 Apr 28     [PubMed PMID: 32342334]


[14]

Zhou WJ, Wang X, Peng JY, Ma SC, Zhang DN, Guan XD, Diao JF, Niu JX, Li CD, Jia W. Clinical Features and Prognostic Risk Factors of Choroid Plexus Tumors in Children. Chinese medical journal. 2018 Dec 20:131(24):2938-2946. doi: 10.4103/0366-6999.247195. Epub     [PubMed PMID: 30539906]


[15]

Piguet V, de Tribolet N. Choroid plexus papilloma of the cerebellopontine angle presenting as a subarachnoid hemorrhage: case report. Neurosurgery. 1984 Jul:15(1):114-6     [PubMed PMID: 6332280]

Level 3 (low-level) evidence

[16]

Jamjoom AA, Sharab MA, Jamjoom AB, Satti MB. Rapid evolution of a choroid plexus papilloma in an infant. British journal of neurosurgery. 2009 Jun:23(3):324-5. doi: 10.1080/02688690902756694. Epub     [PubMed PMID: 19533469]

Level 3 (low-level) evidence

[17]

Mula-Hussain L, Malone J, Dos Santos MP, Sinclair J, Malone S. CSF Rhinorrhea: A Rare Clinical Presentation of Choroid Plexus Papilloma. Current oncology (Toronto, Ont.). 2021 Jan 31:28(1):750-756. doi: 10.3390/curroncol28010073. Epub 2021 Jan 31     [PubMed PMID: 33572678]


[18]

Navarro-Olvera JL, Covaleda-Rodriguez JC, Diaz-Martinez JA, Aguado-Carrillo G, Carrillo-Ruiz JD, Velasco-Campos F. Hemifacial Spasm Associated with Compression of the Facial Colliculus by a Choroid Plexus Papilloma of the Fourth Ventricle. Stereotactic and functional neurosurgery. 2020:98(3):145-149. doi: 10.1159/000507060. Epub 2020 Apr 21     [PubMed PMID: 32316018]


[19]

Li Y, Chetty S, Feldstein VA, Glenn OA. Bilateral Choroid Plexus Papillomas Diagnosed by Prenatal Ultrasound and MRI. Cureus. 2021 Mar 6:13(3):e13737. doi: 10.7759/cureus.13737. Epub 2021 Mar 6     [PubMed PMID: 33842115]


[20]

Cao LR, Chen J, Zhang RP, Hu XL, Fang YL, Cai CQ. Choroid Plexus Papilloma of Bilateral Lateral Ventricle in an Infant Conceived by in vitro Fertilization. Pediatric neurosurgery. 2018:53(6):401-406. doi: 10.1159/000491639. Epub 2018 Nov 2     [PubMed PMID: 30391955]


[21]

Pandey SK, Mani SE, Sudhakar SV, Panwar J, Joseph BV, Rajshekhar V. Reliability of Imaging-Based Diagnosis of Lateral Ventricular Masses in Children. World neurosurgery. 2019 Apr:124():e693-e701. doi: 10.1016/j.wneu.2018.12.196. Epub 2019 Jan 17     [PubMed PMID: 30660880]


[22]

Dangouloff-Ros V, Grevent D, Pagès M, Blauwblomme T, Calmon R, Elie C, Puget S, Sainte-Rose C, Brunelle F, Varlet P, Boddaert N. Choroid Plexus Neoplasms: Toward a Distinction between Carcinoma and Papilloma Using Arterial Spin-Labeling. AJNR. American journal of neuroradiology. 2015 Sep:36(9):1786-90. doi: 10.3174/ajnr.A4332. Epub 2015 May 28     [PubMed PMID: 26021621]


[23]

Laarakker AS, Nakhla J, Kobets A, Abbott R. Incidental choroid plexus papilloma in a child: A difficult decision. Surgical neurology international. 2017:8():86. doi: 10.4103/sni.sni_386_16. Epub 2017 May 26     [PubMed PMID: 28607820]


[24]

Ito H, Nakahara Y, Kawashima M, Masuoka J, Abe T, Matsushima T. Typical Symptoms of Normal-Pressure Hydrocephalus Caused by Choroid Plexus Papilloma in the Cerebellopontine Angle. World neurosurgery. 2017 Feb:98():875.e13-875.e17. doi: 10.1016/j.wneu.2016.11.106. Epub 2016 Nov 29     [PubMed PMID: 27913261]


[25]

Toescu SM, James G, Phipps K, Jeelani O, Thompson D, Hayward R, Aquilina K. Intracranial Neoplasms in the First Year of Life: Results of a Third Cohort of Patients From a Single Institution. Neurosurgery. 2019 Mar 1:84(3):636-646. doi: 10.1093/neuros/nyy081. Epub     [PubMed PMID: 29617945]


[26]

Aljared T, Farmer JP, Tampieri D. Feasibility and value of preoperative embolization of a congenital choroid plexus tumour in the premature infant: An illustrative case report with technical details. Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences. 2016 Dec:22(6):732-735     [PubMed PMID: 27605545]

Level 2 (mid-level) evidence

[27]

Kim IY, Niranjan A, Kondziolka D, Flickinger JC, Lunsford LD. Gamma knife radiosurgery for treatment resistant choroid plexus papillomas. Journal of neuro-oncology. 2008 Oct:90(1):105-10. doi: 10.1007/s11060-008-9639-9. Epub 2008 Jun 28     [PubMed PMID: 18587534]


[28]

Jung GS, Ruschel LG, Leal AG, Ramina R. Embolization of a giant hypervascularized choroid plexus papilloma with onyx by direct puncture: a case report. Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery. 2016 Apr:32(4):717-21. doi: 10.1007/s00381-015-2915-z. Epub 2015 Oct 5     [PubMed PMID: 26438551]

Level 3 (low-level) evidence

[29]

Turkoglu E, Kertmen H, Sanli AM, Onder E, Gunaydin A, Gurses L, Ergun BR, Sekerci Z. Clinical outcome of adult choroid plexus tumors: retrospective analysis of a single institute. Acta neurochirurgica. 2014 Aug:156(8):1461-8; discussion 1467-8. doi: 10.1007/s00701-014-2138-1. Epub 2014 May 28     [PubMed PMID: 24866474]

Level 2 (mid-level) evidence

[30]

Morshed RA, Lau D, Sun PP, Ostling LR. Spinal drop metastasis from a benign fourth ventricular choroid plexus papilloma in a pediatric patient: case report. Journal of neurosurgery. Pediatrics. 2017 Nov:20(5):471-479. doi: 10.3171/2017.5.PEDS17130. Epub 2017 Aug 25     [PubMed PMID: 28841111]

Level 3 (low-level) evidence

[31]

Anderson MD, Theeler BJ, Penas-Prado M, Groves MD, Yung WK. Bevacizumab use in disseminated choroid plexus papilloma. Journal of neuro-oncology. 2013 Sep:114(2):251-3. doi: 10.1007/s11060-013-1180-9. Epub 2013 Jun 13     [PubMed PMID: 23761024]

Level 3 (low-level) evidence

[32]

Muly S, Liu S, Lee R, Nicolaou S, Rojas R, Khosa F. MRI of intracranial intraventricular lesions. Clinical imaging. 2018 Nov-Dec:52():226-239. doi: 10.1016/j.clinimag.2018.07.021. Epub 2018 Aug 1     [PubMed PMID: 30138862]


[33]

Siegfried A, Morin S, Munzer C, Delisle MB, Gambart M, Puget S, Maurage CA, Miquel C, Dufour C, Leblond P, André N, Branger DF, Kanold J, Kemeny JL, Icher C, Vital A, Coste EU, Bertozzi AI. A French retrospective study on clinical outcome in 102 choroid plexus tumors in children. Journal of neuro-oncology. 2017 Oct:135(1):151-160. doi: 10.1007/s11060-017-2561-2. Epub 2017 Jul 4     [PubMed PMID: 28677107]

Level 2 (mid-level) evidence

[34]

Safaee M, Oh MC, Sughrue ME, Delance AR, Bloch O, Sun M, Kaur G, Molinaro AM, Parsa AT. The relative patient benefit of gross total resection in adult choroid plexus papillomas. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia. 2013 Jun:20(6):808-12. doi: 10.1016/j.jocn.2012.08.003. Epub 2013 Apr 25     [PubMed PMID: 23623658]


[35]

Abdulkader MM, Mansour NH, Van Gompel JJ, Bosh GA, Dropcho EJ, Bonnin JM, Cohen-Gadol AA. Disseminated choroid plexus papillomas in adults: A case series and review of the literature. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia. 2016 Oct:32():148-54. doi: 10.1016/j.jocn.2016.04.002. Epub 2016 Jun 29     [PubMed PMID: 27372242]

Level 2 (mid-level) evidence

[36]

Fujimura M, Onuma T, Kameyama M, Motohashi O, Kon H, Yamamoto K, Ishii K, Tominaga T. Hydrocephalus due to cerebrospinal fluid overproduction by bilateral choroid plexus papillomas. Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery. 2004 Jul:20(7):485-8     [PubMed PMID: 14986042]

Level 3 (low-level) evidence

[37]

Ward C, Phipps K, de Sousa C, Butler S, Gumley D. Treatment factors associated with outcomes in children less than 3 years of age with CNS tumours. Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery. 2009 Jun:25(6):663-8. doi: 10.1007/s00381-009-0832-8. Epub 2009 Feb 27     [PubMed PMID: 19247674]


[38]

Lechanoine F, Zemmoura I, Velut S. Treating Cerebrospinal Fluid Rhinorrhea without Dura Repair: A Case Report of Posterior Fossa Choroid Plexus Papilloma and Review of the Literature. World neurosurgery. 2017 Dec:108():990.e1-990.e9. doi: 10.1016/j.wneu.2017.08.121. Epub 2017 Sep 1     [PubMed PMID: 28866068]

Level 3 (low-level) evidence

[39]

Hallaert GG, Vanhauwaert DJ, Logghe K, Van den Broecke C, Baert E, Van Roost D, Caemaert J. Endoscopic coagulation of choroid plexus hyperplasia. Journal of neurosurgery. Pediatrics. 2012 Feb:9(2):169-77. doi: 10.3171/2011.11.PEDS11154. Epub     [PubMed PMID: 22295923]

Level 3 (low-level) evidence

[40]

Boyd MC, Steinbok P. Choroid plexus tumors: problems in diagnosis and management. Journal of neurosurgery. 1987 Jun:66(6):800-5     [PubMed PMID: 3572508]

Level 3 (low-level) evidence

[41]

Smith AB, Smirniotopoulos JG, Horkanyne-Szakaly I. From the radiologic pathology archives: intraventricular neoplasms: radiologic-pathologic correlation. Radiographics : a review publication of the Radiological Society of North America, Inc. 2013 Jan-Feb:33(1):21-43. doi: 10.1148/rg.331125192. Epub     [PubMed PMID: 23322825]