Figure 1
Coronal contrast enhanced CT
A tongue-like projection from the right lobe of liver can be well appreciated on this coronal CT image.
Riedel\'s Lobe: Did you know these facts?
SectionAbdominal imaging
Case TypeAnatomy and Functional Imaging
Authors
Arora A, Mukund A, Thapar S, Jain D
Department of Radiodiagnosis, Institute of Liver and Biliary Sciences, New Delhi, India
Connected authors
21 years, male
Clinical History
A 21-year-old male patient was imaged following splenectomy and spleno-renal shunt creation.
Imaging Findings
Incidental note was made of an elongated tongue-like projection from the right lobe of liver extending almost up to the level of iliac crest (Fig. 1-4). Review of pre-operative images also confirmed the presence of this normal but uncommon variant.
Discussion
The present case displays the characteristic appearance of Riedel’s lobe. A PubMed search pertaining to the clinical relevance of this infrequently encountered normal-variant revealed many interesting facts, which are presented herein.
Riedel's lobe is a normal anatomical variant referring to a tongue-like projection extending caudally from the right lobe of liver lateral to the gallbladder. It was first described by Riedel, a French surgeon in 1888. Although believed to be an accessory lobe, truly speaking it is not a true-accessory lobe but a downward projection of the right hepatic-lobe [1, 2]. It has been observed more frequently in females, its prevalence being dependent on age-related changes in liver size and skeletal shape. Its incidence in the general population varies with a considerably wide range from 3.3-31% [2].
It is imperative for the clinician and radiologists to know about this normal-variant, as the lobe may enlarge, sometimes extending into the right iliac fossa, and mistaken for pathological enlargement of the liver or a right-renal-mass on clinical examination [1-3, 14].
Another clinical significance of Riedel's lobe for the radiologist is to carefully examine the liver up to the lower-most tip as pathologies such as hepatocellular carcinoma and metastasis may sometimes affect only the lowest-part of the Riedel's lobe [7, 8, 2]. It is therefore of utmost importance to cover the entire liver in the scan-field.
At times, this lobe may show only a narrow-attachment to the right-lobe acting as a pedunculated lobe. Cases of torsion and infarction of Riedel’s lobe and accessory hepatic lobes have been reported [4, 9-12]. Hence, radiologist should be aware of this possibility and in appropriate settings should consider this diagnostic possibility.
Recent literature highlighted a left-sided Riedel's lobe which manifested with gastric outlet obstruction. On exploratory laparotomy a 10x6cm-sized tongue-like lobe from left-lobe of liver was seen extending to the umbilicus and compressing the prepyloric area of the stomach [6].
The presence of Riedel's lobe can be challenging for the nephrologist performing laproscopic interventions[5, 13]. Riedel's lobe chiefly presents two special technical concerns. It limits intraperitoneal access and limits the hilar exposure. For intraperitoneal access, an initial supraumbilical approach, or possibly an open approach, has been suggested to lessen the risk of liver injury. For renal and hilar exposure, it is suggested that the right lateral liver attachments should be taken down so that the hepatic lobe can be retracted medially instead of in the conventional cephalad direction[5].
Riedel's lobe is a normal anatomical variant referring to a tongue-like projection extending caudally from the right lobe of liver lateral to the gallbladder. It was first described by Riedel, a French surgeon in 1888. Although believed to be an accessory lobe, truly speaking it is not a true-accessory lobe but a downward projection of the right hepatic-lobe [1, 2]. It has been observed more frequently in females, its prevalence being dependent on age-related changes in liver size and skeletal shape. Its incidence in the general population varies with a considerably wide range from 3.3-31% [2].
It is imperative for the clinician and radiologists to know about this normal-variant, as the lobe may enlarge, sometimes extending into the right iliac fossa, and mistaken for pathological enlargement of the liver or a right-renal-mass on clinical examination [1-3, 14].
Another clinical significance of Riedel's lobe for the radiologist is to carefully examine the liver up to the lower-most tip as pathologies such as hepatocellular carcinoma and metastasis may sometimes affect only the lowest-part of the Riedel's lobe [7, 8, 2]. It is therefore of utmost importance to cover the entire liver in the scan-field.
At times, this lobe may show only a narrow-attachment to the right-lobe acting as a pedunculated lobe. Cases of torsion and infarction of Riedel’s lobe and accessory hepatic lobes have been reported [4, 9-12]. Hence, radiologist should be aware of this possibility and in appropriate settings should consider this diagnostic possibility.
Recent literature highlighted a left-sided Riedel's lobe which manifested with gastric outlet obstruction. On exploratory laparotomy a 10x6cm-sized tongue-like lobe from left-lobe of liver was seen extending to the umbilicus and compressing the prepyloric area of the stomach [6].
The presence of Riedel's lobe can be challenging for the nephrologist performing laproscopic interventions[5, 13]. Riedel's lobe chiefly presents two special technical concerns. It limits intraperitoneal access and limits the hilar exposure. For intraperitoneal access, an initial supraumbilical approach, or possibly an open approach, has been suggested to lessen the risk of liver injury. For renal and hilar exposure, it is suggested that the right lateral liver attachments should be taken down so that the hepatic lobe can be retracted medially instead of in the conventional cephalad direction[5].
Differential Diagnosis List
Riedel's lobe
Accessory lobe
Hepatomegaly
Final Diagnosis
Riedel's lobe
References
[1] Yano K, Ohtsubo M, Mizota T, Kato H, Hayashida Y, Morita S, Furukawa R, Hayakawa A (2000) Riedel\'s lobe of the liver evaluated by multiple imaging modalities. Intern Med 39:136-8 (PMID: 10732830)
[2] Kudo M (2000) Riedel\'s lobe of the liver and its clinical implication. Intern Med 39:87-8 (PMID: 10732821)
[3] Gillard JH, Patel MC, Abrahams PH, Dixon AK (1998) Riedel\'s lobe of the liver: fact or fiction?. in Anat 11:47-9 (PMID: 9445097)
[4] Lefaucher C, Dupuis E, Muller J, Laham A (1978) [Torsion of Riedel\'s lobe. Two cases (author\'s transl)]. J Chir (Paris) 115:25-8 (PMID: 632329)
[5] Chien GW, Orvieto MA, Galocy RM, Sokoloff MH, Shahav AL (2005) Technical considerations for laparoscopic right renal surgery in presence of Riedel\'s lobe of the liver. J Endourol 19:300-2 (PMID: 15865517)
[6] Akbulut S, Cakabay B, Sevinc MM, Basak F (2011) Gastric outlet obstruction caused by Riedel\'s lobe of the liver: a diagnostic and therapeutic challenge for surgeons. Hepatogastroenterology 58:589-92 (PMID: 21661436)
[7] Zamfir R, Braşoveanu V, Boroş M, Herlea V, Popescu I (2008) Hepatocellular carcinoma in Riedel\'s lobe. Chirurgia (Bucur) 103:121-3 (PMID: 18459510)
[8] Soo MS, Adatepe MH (1990) Metastatic lesions arising in a Riedel\'s lobe. Findings from a sulfur colloid liver-spleen scan. Clin Nucl Med 15:814-5 (PMID: 1963389)
[9] Popescu I, Zamfir R, Braşoveanu V, Boroş M, Herlea V (2005) A rare indication for liver resection. Chirurgia (Bucur) 100:75-8 (PMID: 15810710)
[10] Khan AM, Hundal R, Manzoor K, Dhuper S, Korsten MA (2006) Accessory liver lobes: a diagnostic and therapeutic challenge of their torsions. Scand J Gastroenterol 41:125-30 (PMID: 16484115)
[11] Hundal RS, Ali J, Korsten MA, Khan AM (2006) Torsion and infarction of an accessory liver lobe. Z Gastroenterol 44:1223-6 (PMID: 17163372)
[12] Koplewitz BZ, Manson DE, Ein SH (1999) Posttraumatic torsion of accessory lobe of the liver and the gallbladder. Pediatr Radiol 29:799-802 (PMID: 10552054)
[13] Miyake M, Makiyama K, Nakaigawa N, Miyoshi Y, Sano F, Ogawa T, Uemura H, Yao M, Kubota Y (2009) [Laparoscopic right partial nephrectomy in the presence of Riedel\'s lobe of the liver]. Hinyokika Kiyo 55:509-11 (PMID: 19764539)
[14] Wolf DC (1990) Evaluation of the Size, Shape, and Consistency of the Liver. In: Walker HK, Hall WD, Hurst JW, editors. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition. Boston: Butterworths Chapter 94 (PMID: 21250261)
Case information
| URL: | https://www.eurorad.org/case/9437 |
| DOI: | 10.1594/EURORAD/CASE.9437 |
| ISSN: | 1563-4086 |
Figure 2
Coronal contrast enhanced CT
An elongated tongue-like projection is seen from the right lobe extending caudally up to the level of pelvic inlet.
Figure 3
Sagittal contrast enhanced CT image
Sagittal CT image superiorly delineates the Riedel\'s lobe.
Figure 4
Riedel\'s lobe
Riedel\'s lobe: an elongated tongue-like projection from the right lobe of liver.
Coronal contrast enhanced CT
A tongue-like projection from the right lobe of liver can be well appreciated on this coronal CT image.
Coronal contrast enhanced CT
An elongated tongue-like projection is seen from the right lobe extending caudally up to the level of pelvic inlet.
Sagittal contrast enhanced CT image
Sagittal CT image superiorly delineates the Riedel\'s lobe.
Riedel\'s lobe
Riedel\'s lobe: an elongated tongue-like projection from the right lobe of liver.