- Email: [email protected]
Re: Article by Gonoi et al.
Clinical Imaging 36 (2012) 84
Correspondence Re: Article by Gonoi et al. To the Editor, In 2008, Leyendecker and Baginski [1] coined the term “circumportal pancreas” to describe an anatomical variant characterized by complete encirclement of the main portal vein by pancreatic tissue. This variant was not recognized well in the past, but recently, the number of reports describing this variant has increased substantially. We read with interest the article “Retroportal main pancreatic duct with circumportal pancreas: radiographic visualization” by Gonoi et al. [2]. The authors seemed to exclude cases of circumportal pancreas with infrasplenic vein type (or pancreatic encasement of the superior mesenteric vein) from their evaluation. Indeed, they excluded two cases [3,4] reporting such a type in their literature review. The term “circumportal” pancreas may indicate that pancreatic tissue encircles the portal vein, not the superior mesenteric vein. However, we would like to propose that circumportal pancreas should include cases involved not only with the portal vein but also with superior mesenteric vein because malfusion between the ventral and dorsal pancreatic buds is the basis of the occurrence of this variant. Recently, Karasaki et al. [5] classified circumportal pancreas into three types: suprasplenic vein type, infrasplenic vein type and mixed type. A similar classification has been proposed as well by Joseph et al. [6]. The prevalence of circumportal pancreas accompanied with retroportal main pancreatic duct is reported as being 0.01% (2 of 20,000) in the study of Gonoi et al., although it is not clear from the study how many cases of circumportal pancreas without retroportal main duct were detected. It should be noted that other image studies show a considerably higher rate of circumportal pancreas ranging from 1.1% to 3.4% [5,7,8]. In our own experience, we encountered two cases of surgically proved circumportal pancreas out of over 1000 deceased donor pancreata processed for islet transplantation [9,10]. Other terms such as “periportal pancreas” and “portal annular pancreas” have been used to describe circumportal pancreas. As a result, previous reports have inaccurately tallied the total number of published cases having this variant.
0899-7071/$ – see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1016/j.clinimag.2011.07.003
With the help of current imaging modalities and widespread recognition of this variant, significant insights into the complex process in pancreas organogenesis will be provided.
Tatsuya Kin James Shapiro University of Alberta Clinical Islet Laboratory 210 Collge Plaza 8215-112 St Edmonton Alberta, Canada T6G 2C8 E-mail addresses: [email protected], [email protected] References [1] Leyendecker JR, Baginski SG. Complete pancreatic encasement of the portal vein (circumportal pancreas): imaging findings and implications of a rare pancreatic anomaly. J Comput Assist Tomogr 2008;32:61–4. [2] Gonoi W, Akahane M, Akai H, Hagiwara K, Kiryu S, Hayashi N, Ohtomo K. Retroportal main pancreatic duct with circumportal pancreas: radiographic visualization. Clin Imaging 2011;35(6):442–6. [3] Sugiura Y, Shima S, Yonekawa H, Yoshizumi Y, Ohtsuka H, Ogata T. The hypertrophic uncinate process of the pancreas wrapping the superior mesenteric vein and artery: a case report. Jap J Surg 1987;17: 182–5. [4] Yamazaki S, Kaneko T, Fujinaga Y, Kadoya M, Ochi Y, Sasaki K. CT and MRI features of unclassifiable pancreatic anomaly with superior mesenteric vein running through the pancreatic parenchyma. Eur J Radiol Extra 2005;54:59–61. [5] Karasaki H, Mizukami Y, Ishizaki A, Goto J, Yoshikawa D, Kino S, Tokusashi Y, Miyokawa N, Yamada T, Kono T, Kasai S. Portal annular pancreas, a notable pancreatic malformation: frequency, morphology, and implications for pancreatic surgery. Surgery 2009;146:515–8. [6] Joseph P, Raju RS, Vyas FL, Eapen A, Sitaram V. Portal annular pancreas. A rare variant and a new classification. JOP 2010;11:453–5. [7] Song SY, Oh JY, Kim Y, Cho OK, Koh BH. Complete pancreatic encasement of portal vein: circumportal pancreas. Eur Radiol Suppl 2008;18:350 [Abstract]. [8] Ishigami K, Tajima T, Nishie A, Asayama Y, Kakihara D, Nakayama T, Shirabe K, Taketomi A, Nakamura M, Takahata S, Ito T, Honda H. The prevalence of circumportal pancreas as shown by multidetectorrow computed tomography. Insights Imaging 2011;2:409–14. [9] Kin T, Shapiro AMJ. Circumportal pancreas and islet isolation. Surgery 2009;146:126–7. [10] Kin T, Shapiro AMJ. Partial dorsal agenesis accompanied with circumportal pancreas in a donor for islet transplantation. Islets 2010;2: 146–8.
Correspondence Re: Article by Gonoi et al. To the Editor, In 2008, Leyendecker and Baginski [1] coined the term “circumportal pancreas” to describe an anatomical variant characterized by complete encirclement of the main portal vein by pancreatic tissue. This variant was not recognized well in the past, but recently, the number of reports describing this variant has increased substantially. We read with interest the article “Retroportal main pancreatic duct with circumportal pancreas: radiographic visualization” by Gonoi et al. [2]. The authors seemed to exclude cases of circumportal pancreas with infrasplenic vein type (or pancreatic encasement of the superior mesenteric vein) from their evaluation. Indeed, they excluded two cases [3,4] reporting such a type in their literature review. The term “circumportal” pancreas may indicate that pancreatic tissue encircles the portal vein, not the superior mesenteric vein. However, we would like to propose that circumportal pancreas should include cases involved not only with the portal vein but also with superior mesenteric vein because malfusion between the ventral and dorsal pancreatic buds is the basis of the occurrence of this variant. Recently, Karasaki et al. [5] classified circumportal pancreas into three types: suprasplenic vein type, infrasplenic vein type and mixed type. A similar classification has been proposed as well by Joseph et al. [6]. The prevalence of circumportal pancreas accompanied with retroportal main pancreatic duct is reported as being 0.01% (2 of 20,000) in the study of Gonoi et al., although it is not clear from the study how many cases of circumportal pancreas without retroportal main duct were detected. It should be noted that other image studies show a considerably higher rate of circumportal pancreas ranging from 1.1% to 3.4% [5,7,8]. In our own experience, we encountered two cases of surgically proved circumportal pancreas out of over 1000 deceased donor pancreata processed for islet transplantation [9,10]. Other terms such as “periportal pancreas” and “portal annular pancreas” have been used to describe circumportal pancreas. As a result, previous reports have inaccurately tallied the total number of published cases having this variant.
0899-7071/$ – see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1016/j.clinimag.2011.07.003
With the help of current imaging modalities and widespread recognition of this variant, significant insights into the complex process in pancreas organogenesis will be provided.
Tatsuya Kin James Shapiro University of Alberta Clinical Islet Laboratory 210 Collge Plaza 8215-112 St Edmonton Alberta, Canada T6G 2C8 E-mail addresses: [email protected], [email protected] References [1] Leyendecker JR, Baginski SG. Complete pancreatic encasement of the portal vein (circumportal pancreas): imaging findings and implications of a rare pancreatic anomaly. J Comput Assist Tomogr 2008;32:61–4. [2] Gonoi W, Akahane M, Akai H, Hagiwara K, Kiryu S, Hayashi N, Ohtomo K. Retroportal main pancreatic duct with circumportal pancreas: radiographic visualization. Clin Imaging 2011;35(6):442–6. [3] Sugiura Y, Shima S, Yonekawa H, Yoshizumi Y, Ohtsuka H, Ogata T. The hypertrophic uncinate process of the pancreas wrapping the superior mesenteric vein and artery: a case report. Jap J Surg 1987;17: 182–5. [4] Yamazaki S, Kaneko T, Fujinaga Y, Kadoya M, Ochi Y, Sasaki K. CT and MRI features of unclassifiable pancreatic anomaly with superior mesenteric vein running through the pancreatic parenchyma. Eur J Radiol Extra 2005;54:59–61. [5] Karasaki H, Mizukami Y, Ishizaki A, Goto J, Yoshikawa D, Kino S, Tokusashi Y, Miyokawa N, Yamada T, Kono T, Kasai S. Portal annular pancreas, a notable pancreatic malformation: frequency, morphology, and implications for pancreatic surgery. Surgery 2009;146:515–8. [6] Joseph P, Raju RS, Vyas FL, Eapen A, Sitaram V. Portal annular pancreas. A rare variant and a new classification. JOP 2010;11:453–5. [7] Song SY, Oh JY, Kim Y, Cho OK, Koh BH. Complete pancreatic encasement of portal vein: circumportal pancreas. Eur Radiol Suppl 2008;18:350 [Abstract]. [8] Ishigami K, Tajima T, Nishie A, Asayama Y, Kakihara D, Nakayama T, Shirabe K, Taketomi A, Nakamura M, Takahata S, Ito T, Honda H. The prevalence of circumportal pancreas as shown by multidetectorrow computed tomography. Insights Imaging 2011;2:409–14. [9] Kin T, Shapiro AMJ. Circumportal pancreas and islet isolation. Surgery 2009;146:126–7. [10] Kin T, Shapiro AMJ. Partial dorsal agenesis accompanied with circumportal pancreas in a donor for islet transplantation. Islets 2010;2: 146–8.