Left Lateral Lobe Research Articles

Computed tomography scan accuracy for the prediction of lobe and division of liver tumors by four board-certified radiologists.

(1) Evaluate the accuracy of computed tomography (CT) scans for localization of liver masses. (2) Assess the agreement between radiologists on localization. (3) Determine if location influences the accuracy of localization and histopathologic diagnosis. (4) Determine what lobar vasculature radiologists found most useful for localization. Retrospective. A total of 67 client-owned dogs with a total of 75 hepatic masses. Records were reviewed for relevant data. Localization for each hepatic mass was performed by four radiologists (JH, EH, ML, JF) independently. Overall accuracy of mass localization was 217/292 (74.3%) by lobe and 264/300 (88%) by division. Accuracy for the quadrate lobe (11/27, 40.7%) was lower (p < .05) than for the caudate process of the caudate lobe (19/24, 79.2%), left medial lobe (47/64, 73.4%) and left lateral lobe (95/101, 89.6%). Accuracy for the right lateral lobe (17/35, 48.6%) was lower (p < .05) lower than for the left lateral lobe (95/101, 89.6%). Accuracy of localization was 173/192 (90.1%) for masses located in the left division, 37/48 (77.1%) in the central division, and 53/60 (88.3%) for the right division. The agreement (kappa) between radiologists was good (0.61-0.8) to excellent (0.81-1) for division and moderate (0.41-0.6) to good for lobe localization. CT localization was more accurate for division than lobe localization of canine hepatic masses. Similarly, radiologists had a better agreement for division than lobe localization. This study supports CT as a useful modality for liver mass localization based on division. CT localization to specific lobes should be interpreted with some caution.

Modified hepatic left lateral lobe inversion in laparoscopic proximal gastrectomy: An analysis of 13 cases.

In laparoscopic proximal gastrectomy (LPG), the prolapse of the hepatic left lateral lobe near the lesser curvature and esophageal hiatus can obstruct the field of vision and operation. Therefore, it is necessary to retract or obstruct the hepatic left lateral lobe to ensure a clear field of vision. To investigate the safety and clinical efficacy of the modified hepatic left lateral lobe inversion technique for LPG. A retrospective analysis was conducted on the clinical data of 13 consecutive patients with early-stage upper gastric adenocarcinoma or adenocarcinoma of the esophagogastric junction treated with LPG from January to December 2023 at the Department of Gastrointestinal Surgery, Second Affiliated Hospital of Fujian Medical University. The modified hepatic left lateral lobe inversion technique was used to expose the surgical field in all patients, and short-term outcomes were observed. In all 13 patients, the modified hepatic left lateral lobe inversion technique was successful during surgery without the need for re-retraction or alteration of the liver traction method. There were no instances of esophageal hiatus occlusion, eliminating the need for forceps to assist in exposure. There was no occurrence of intraoperative hepatic hemorrhage, hepatic vein injury, or hepatic congestion. No postoperative digestive complications of Clavien-Dindo grade ≥ II occurred within 30 days after surgery, except for a single case of pulmonary infection. Some patients experienced increases in alanine aminotransferase and aspartate aminotransferase levels on the first day after surgery, which significantly decreased by the third day and returned to normal by the seventh day after surgery. The modified hepatic left lateral lobe inversion technique has demonstrated satisfactory results, offering advantages in terms of facilitating surgical procedures, reducing surgical trauma, and protecting the liver.

Intra- and interobserver agreement in computed tomography localization of primary nonhematopoietic hepatic masses and comparison with surgical and histopathological outcomes in 21 cats.

Computed tomography (CT) is commonly used in the staging of hepatic masses and for liver lobectomy planning. Mass location is an important factor in determining the feasibility of resection, including surgical technique and the likelihood of surgical complications. The objectives of this retrospective descriptive cross-sectional, observer agreement, method comparison study were to assess the reliability of CT in correctly determining the hepatic division and lobar site of origin of feline primary nonhematopoietic hepatic masses, compared with surgically confirmed locations. Furthermore, it provides an overview of the types and locations of liver masses found in a cohort of cats. Pre- and postcontrast CT images of 21 cats were independently and simultaneously reviewed by two observers. Intra- and interobserver agreements and descriptive statistics on demographic and histological diagnoses were calculated. Based on surgical assessment, it was found that masses most frequently originated from the left hepatic division (13/24, 54%). The most frequent lobar origins were the left lateral (8/24, 33%), left medial (5/24, 21%), and right medial lobes (5/24, 21%). No masses were found originating from the right lateral lobe. CT correctly determined hepatic division and lobar origin in 76% of cases, with good-to-excellent intra- and interobserver agreement. The hepatic division had higher agreements overall for both observers. Most of the masses were benign (17/21, 81%), and the most prevalent histological diagnoses were biliary cystadenoma (11/21, 52%) and hepatocellular adenoma (6/21, 29%). Findings suggest that postcontrast CT is a reliable method for correctly determining hepatic mass division and lobar origin in cats.

Spontaneous type II cell-derived bronchioloalveolar adenoma in a young ICR mouse.

Although pulmonary adenomas have been reported in ICR mice, spontaneous adenomas have not been reported in mice aged ≤10 weeks. Here, we report a well-circumscribed nodule (1 mm × 1 mm) in the peripheral lesion of the left lateral lobe of a 10-week-old male ICR mouse. Histopathologic evaluation revealed a well-demarcated nodule compressing the surrounding tissue. The neoplastic cells were polygonal with indistinct cellular borders, round/oval nuclei and abundant cytoplasm. These characteristics led to the diagnosis of type II cell-derived bronchioloalveolar adenoma. Given that they are generally observed in aged laboratory animals, this case represents a rare manifestation of a spontaneous tumor in young laboratory mice before puberty.

Pattern and extent of intrahepatic infiltration of perihilar cholangiocarcinoma - A case-control study based on liver panoramic digital pathology.

The extent of intrahepatic infiltration of perihilar cholangiocarcinoma (PHCC) remains unclear. This research aimed to explore the pattern and extent of intrahepatic infiltration of PHCC to guide surgical treatment and pathological research. This study included 62 patients diagnosed with PHCC who underwent major hepatectomy. A whole-mount digital liver pathology system (WDLPS) for hepatectomy specimens greater than 10 × 10cm was used to panoramically assess the intrahepatic infiltration extent of PHCC. The distal intrahepatic infiltration (DIHI) and radial liver invasion (RLI) were important parts of intrahepatic infiltration for PHCC explored by WDLPS. The study confirmed that 75.8% of PHCCs had RLI and the infiltration distance in all patients were within 15,000 µm, 62.9% of PHCCs had DIHI greater than 1cm away from the main tumor in liver parenchyma. The recurrence-free survival rates and overall survival rates of patients with DIHI were poorer than the patients without DIHI (P＜0.0001, P=0.0038). Arterial invasion on the resected side could be an excellent predictor. A total of 105 liver lobes were resected from 62 PHCC patients. The invasion rates of the left lateral, left medial, right anterior, and right posterior lobe of PHCC were 79%, 100, 100%, and 69% respectively. The presence of DIHI in most PHCCs was a significant predictor of poor postoperative recurrence and survival. Based on the extent of intrahepatic infiltration, minor hepatectomy was not suitable as the curative surgery for PHCC. Major hepatectomy and liver transplantation were the ideal radical treatment.

Loneliness and Resting-State Functional Brain Connectivity Among Older Adults: A Proportional Correlation.

Loneliness reportedly increases the risk of dementia, especially Alzheimer's disease (AD). The authors' previous study demonstrated associations between loneliness and structural abnormalities observed in early-stage AD. The present study examined associations between the brain's functional characteristics and loneliness among older adults with concerns about cognitive decline. This single-center study included 43 participants (13 with amnestic mild cognitive impairment and 30 with normal cognition). Participants were assessed with the revised University of California Los Angeles (UCLA) Loneliness Scale and underwent resting-state functional MRI. Functional images were preprocessed with the CONN toolbox. The selected seeds were within brain regions reportedly associated with loneliness. One-sample general linear model analysis was performed to examine regressions of UCLA Loneliness Scale scores and functional connectivity between the seeds and regions of interest. The revised UCLA Loneliness Scale scores were positively correlated with functional connectivity between the right hippocampus and left lateral parietal lobe and were negatively correlated with functional connectivity between the left amygdala and left frontal operculum and between the left amygdala and right supramarginal gyrus. Analyses were adjusted for age, sex, and education and scores on the Mini-Mental State Examination and Clinical Dementia Rating scale. Loneliness was associated with abnormal function of the hippocampus, parts of the parietal lobe and frontal cortex, and the amygdala. These findings may suggest a possible correlation between loneliness and neurological changes associated with dementia.

Similarities and differences of dynamic and static spontaneous brain activity between left and right temporal lobe epilepsy.

To comprehensively investigate the potential temporal dynamic and static abnormalities of spontaneous brain activity (SBA) in left temporal lobe epilepsy (LTLE) and right temporal lobe epilepsy (RTLE) and to detect whether these alterations correlate with cognition. Twelve SBA metrics, including ALFF, dALFF, fALFF, dfALFF, ReHo, dReHo, DC, dDC, GSCorr, dGSCorr, VMHC, and dVMHC, in 46 LTLE patients, 43 RTLE patients, and 53 healthy volunteers were compared in the voxel-wise analysis. Correlation analyses between metrics in regions showing statistic differences and epilepsy duration, epilepsy severity, and cognition scores were also performed. Compared with the healthy volunteers, the alteration of SBA was identified both in LTLE and RTLE patients. The ALFF, fALFF, and dALFF values in LTLE, as well as the fALFF values in RTLE, increased in the bilateral thalamus, basal ganglia, mesial temporal lobe, cerebellum, and vermis. Increased dfALFF in the bilateral basal ganglia, increased ReHoanddReHo in the bilateral thalamus in the LTLE group, increased ALFF and dALFF in the pons, and increased ReHoanddReHo in the right hippocampus in the RTLE group were also detected. However, the majority of deactivation clusters were in the ipsilateral lateral temporal lobe. For LTLE, the fALFF, DC, dDC, and GSCorr values in the left lateral temporal lobe and the ReHo and VMHC values in the bilateral lateral temporal lobe all decreased. For RTLE, the ALFF, fALFF, dfALFF, ReHo, dReHo, and DC values in the right lateral temporal lobe and the VMHC values in the bilateral lateral temporal lobe all decreased. Moreover, for both the LTLE and RTLE groups, the dVMHC values decreased in the calcarine cortex. The most significant difference between LTLE and RTLE was the higher activation in the cerebellum of the LTLE group. The alterations of many SBA metrics were correlated with cognition and epilepsy duration. The patterns of change in SBA abnormalities in the LTLE and RTLE patients were generally similar. The integrated application of temporal dynamic and static SBA metrics might aid in the investigation of the propagation and suppression pathways of seizure activity as well as the cognitive impairment mechanisms in TLE.

Liver fat volume fraction measurements based on multi-material decomposition algorithm in patients with nonalcoholic fatty liver disease: the influences of blood vessel, location, and iodine contrast

BackgroundIn recent years, spectral CT-derived liver fat quantification method named multi-material decomposition (MMD) is playing an increasingly important role as an imaging biomarker of hepatic steatosis. However, there are various measurement ways with various results among different researches, and the impact of measurement methods on the research results is unknown. The aim of this study is to evaluate the reproducibility of liver fat volume fraction (FVF) using MMD algorithm in nonalcoholic fatty liver disease (NAFLD) patients when taking blood vessel, location, and iodine contrast into account during measurement.MethodsThis retrospective study was approved by the institutional ethics committee, and the requirement for informed consent was waived because of the retrospective nature of the study. 101 patients with NAFLD were enrolled in this study. Participants underwent non-contrast phase (NCP) and two-phase enhanced CT scanning (late arterial phase (LAP) and portal vein phase (PVP)) with spectral mode. Regions of interest (ROIs) were placed at right posterior lobe (RPL), right anterior lobe (RAL) and left lateral lobe (LLL) to obtain FVF values on liver fat images without and with the reference of enhanced CT images. The differences of FVF values measured under different conditions (ROI locations, with/without enhancement reference, NCP and enhanced phases) were compared. Friedman test was used to compare FVF values among three phases for each lobe, while the consistency of FVF values was assessed between each two phases using Bland–Altman analysis.ResultsSignificant difference was found between FVF values obtained without and with the reference of enhanced CT images. There was no significant difference about FVF values obtained from NCP images under the reference of enhanced CT images between any two lobes or among three lobes. The FVF value increased after the contrast injection, and there were significant differences in the FVF values among three scanning phases. Poor consistencies of FVF values between each two phases were found in each lobe by Bland–Altman analysis.ConclusionMMD algorithm quantifying hepatic fat was reproducible among different lobes, while was influenced by blood vessel and iodine contrast.

A Hepatocellular Cancer Patient-derived Organoid Xenograft Model to Investigate Impact of Liver Regeneration on Tumor Growth.

Recurrence poses a notable challenge after hepatocellular carcinoma (HCC) treatment, impacting more than 70% of patients who undergo surgical resection. Recurrence stems from undetected micro-metastasis or de novo cancer, potentially triggered by postsurgical liver regeneration. Prior research employed HCC cell lines in orthotopic models to study the impact of liver regeneration, but their limited validity prompted the need for a more representative model. Here, we introduce a novel approach utilizing patient-derived HCC organoids to investigate the influence of liver regeneration on HCC. Patient tumor tissues are processed to create tumor organoids, embedded in a three-dimensional basement membrane matrix, and cultured in a liver-specific medium. One million organoids are injected into the right superior lobe (RSL) of immunodeficient mice, confirming macroscopic tumor growth through sonography. The intervention group undergoes resection of the left lateral lobe (LLL) (30% of total liver volume) or additionally, the middle lobe (ML) (65% of total liver volume) to induce liver regeneration within the tumor site. The control group experiences re-laparotomy without liver tissue resection. After 2 weeks, both groups undergo tumor and normal tissue explantation. In conclusion, this patient-derived HCC organoid model offers a robust platform to investigate the impact of liver regeneration post-cancer resection. Its multi-cellular composition, genetic diversity, and prolonged culture capabilities make it an invaluable tool for studying HCC recurrence mechanisms and potential interventions.

Effect of Different Liver Resection Modalities on the Prognosis of Patients with Hepatocellular Carcinoma on the Left Lateral Lobe [Response to Letter

Effect of Different Liver Resection Modalities on the Prognosis of Patients with Hepatocellular Carcinoma on the Left Lateral Lobe [Response to Letter

Spontaneous intra-abdominal hematomas in a hepatocellular carcinoma patient treated with lenvatinib: a case report

Abstract A 44-year-old patient was admitted with tumor rupture in the left hepatic lateral lobe, and he underwent emergent exploratory laparotomy and proceeded for hepatic left lateral lobectomy on September 19, 2021. The final diagnosis of hepatocellular carcinoma was confirmed by histopathological examination of the surgical specimen. Afterward, the patient received hepatic arterial infusion chemotherapy with FOLFOX (oxaliplatin, fluorouracil, and leucovorin) for 5 cycles. Subsequently, recurrence of the hepatocellular carcinoma was diagnosed in the abdominal cavity. The patient was then treated with lenvatinib. Within less than 1 month of the treatment with lenvatinib, the patient was admitted to the emergency room on June 2, 2022, because of acute intra-abdominal bleeding (hematomas). Percutaneous intra-abdominal angiography found that the bleeding vessels were the right gastroepiploic artery and left gastric artery. The patient was stabilized after arterial embolization using gelatin sponges. The diagnosis and management of spontaneous intra-abdominal hematomas are discussed.

Effect of Different Liver Resection Modalities on the Prognosis of Patients with Hepatocellular Carcinoma on the Left Lateral Lobe [Letter

Effect of Different Liver Resection Modalities on the Prognosis of Patients with Hepatocellular Carcinoma on the Left Lateral Lobe [Letter

An improved model based on quantitative features of right liver lobe, maximum varices, and portal vein system measured on magnetic resonance imaging to predict oesophagogastric variceal haemorrhage secondary to hepatitis B-related cirrhosis.

In patients with hepatitis B-related cirrhosis, it is important to predict those at high-risk of oesophagogastric variceal haemorrhage (OVH) to decide upon prophylactic treatment. Our published model developed with right liver lobe volume and diameters of portal vein system did not incorporate maximum variceal size as a factor. This study thus aimed to develop an improved model based on right liver lobe volume, diameters of maximum oesophagogastric varices (OV) and portal vein system obtained at magnetic resonance imaging (MRI) to predict OVH. Two hundred and thirty consecutive individuals with hepatitis B-related cirrhosis undergoing abdominal enhanced MRI were randomly grouped into training (n=160) and validation sets (n=70). OVH was confirmed in 51 and 23 participants in the training and validation sets during 2-year follow-up period, respectively. Spleen, total liver, right lobe, caudate lobe, left lateral lobe, and left medial lobe volumes, together with diameters of maximum OV and portal venous system were measured on MRI. In the training set, univariate analyses and binary logistic regression analyses were conducted to determine independent predictors. The performance of the model for predicting OVH constructed based on independent predictors from the training set was evaluated with receiver operating characteristic (ROC) analysis and validated in the validation set. The model for predicting OVH was established based on right liver lobe volume and diameters of the maximum OV, left gastric vein, and portal vein [odds ratio (OR) =0.991, 2.462, 1.434, and 1.582, respectively; all P values <0.05]. The logistic regression model equation [-0.009 × right liver lobe volume + 0.901 × maximum OV diameter (MOVD) + 0.361 × left gastric vein diameter (LGVD) + 0.459 × portal vein diameter (PVD) - 7.842] with a cutoff value of -0.656 for predicting OVH obtained excellent performance with an area under ROC curve (AUC) of 0.924 [95% confidence interval (CI): 0.878-0.971]. The Delong test showed negative statistical difference in the model performance between the training and validation sets, with a P value >0.99. The model could help well screen those patients at high risk of OVH for timely intervention and avoiding the fatal complications.

Cathodal HD-tDCS and attention: A study on patients with intractable left lateral frontal lobe epilepsy

ObjectiveDefects in the attentional network in patients with epilepsy are influenced by factors such as the location of epileptic foci. Examining the impact of cathodal high-definition transcranial direct current stimulation (HD-tDCS) on attention components could provide insights into potential attention-related side effects of tDCS. This study aimed to investigate the effect of cathodal HD-tDCS on interictal epileptiform discharges (IEDs), auditory/visual (A/V) attention components, and reaction time (RT) in patients with intractable focal left lateral frontal lobe epilepsy (LFLE). MethodsTo control for variations in individual epilepsy syndrome, 12 adult participants diagnosed with drug-resistant left LFLE with focal cortical IEDs on C3 underwent repeated measurements at pretest, posttest, and follow-up steps. 4 × 1 ring electrodes (cathode on C3 and four anodes on F3, P3, T3, and Cz) delivered 2 mA DC for 20 min per session for 10 consecutive days. The integrated visual and auditory continuous performance test (IVA+) assessed the A/V attention components and RT. One-way repeated-measure ANOVA was used. ResultsThe findings suggest a significant effect in reducing IEDs. The IVA+ results showed a significant improvement in auditory divided attention and visual selective and focused attention (p < 0.05). In the follow-up, these changes demonstrated lasting efficacy. A/V speed scales increased (p < 0.05), showing a significant decrease in reaction time. ConclusionsCathodal HD-tDCS significantly reduced IEDs and improved the components of auditory divided attention, visual focused attention, and visual selective attention, with a reduction in patient reaction time. A significant lasting, side-effect-free positive effect was observed for up to one month after the intervention.

Bile duct hamartoma in a dog

An 11-year-old female Collie presented with a significantly increased abdominal circumference. Computed tomography of the abdomen revealed that the left lateral lobe of the liver contained a large mass, which was excised via laparotomy. Histologically, many small, dilated, cystic luminal structures were anastomosed and connected to a net-like structure. Immunohistochemistry revealed cytokeratin 19-immunopositive areas, representing bile duct structures in the cystic lumen. Based on these results, the tumour was diagnosed as a bile duct hamartoma. To our knowledge, this is the first report of a bile duct hamartoma in a dog.

Hepatic Cavernous Hemangioma Mimicking Malignancy on 18 F-FDG PET/CT Imaging.

A 65-year-old woman was referred to our hospital because of a liver lesion revealed by ultrasound and CT in an outside institution. 18 F-FDG PET/CT images revealed an FDG-avid lesion in the left lateral lobe of the liver. Malignancy cannot be excluded. A subsequent resection was performed to remove the lesion. Postoperative pathology was hepatic cavernous hemangioma. This case suggests that PET/CT findings of FDG-avid hepatic cavernous hemangioma could mimic malignancy.

Association of maternal hypertension during pregnancy with brain structure and behavioral problems in early adolescence.

Emerging evidence suggests an association between maternal hypertension during pregnancy and mental health in the offspring. However, less is known about the role of hypertensive pregnancy in behavioral symptoms and brain structures of the offspring as well as in their developmental changes. Here, we utilized neuroimaging and behavioral data from 11,878 participants aged 9-10years and their 2-year follow-up from the Adolescent Brain Cognitive Development (ABCD) study to investigate the long-term effects of maternal hypertension during pregnancy on early adolescent behavior and brain anatomy. Specifically, adolescents born of mothers with maternal hypertension are at risk of long-lasting behavioral problems, as manifested by higher externalizing and internalizing behavior scores at both 9-10years and 11-12years. These participants additionally presented with a higher cortical thickness, particularly in the fronto-parieto-temporal areas at 9-10years. Four regions, including the left parahippocampus, left lateral orbitofrontal lobe, right superior temporal lobe and right temporal pole, remained thicker 2years later. These findings were partially validated in rats modeled with Nω-nitro-L-arginine methyl ester (L-NAME) preeclampsia. Therefore, clinicians and women who experience hypertension during pregnancy should be warned of this risk, and healthcare providers should recommend appropriate clinical interventions for pregnancy-induced hypertension.

Segmental analysis of liver cirrhosis with different etiologies: a study based on iodine mixed imaging in port-venous phase.

Computed tomography (CT) in port-venous phase can display the intra-hepatic vessels, and may provide the possibility for segment function evaluation for cirrhosis. To assess the value of iodine mixed imaging of dual-source dual-energy CT in port-venous phase in segmental evaluation of liver cirrhosis with different etiologies. Patients diagnosed with liver cirrhosis were enrolled. Patients without cirrhosis were included as a control group. Each patient underwent iodine-contrast enhanced multi-phase dual-energy CT scanning. Parameters were analyzed by SPSS, version 22.0, and Medcalc. In total, 256 patients were investigated, including 114 Child-Pugh A, 51 Child-Pugh B, 41 Child-Pugh C and 50 control patients. Total iodine content (ICt)/body surface area (BSA) in the cirrhosis group was significantly lower than the control group (P < 0.05) and the standardized-iodine parameter (SI) of each segment decreased with cirrhosis progression. In Child-Pugh A and B, SI increased more significantly in the caudal and lateral segment in A (alcholism) than in the V (virus-related) and N (non-alcoholic steatohepatitis) groups (P < 0.001). ICt/BSA showed the best diagnosis power of cirrhosis with an area under the curve of 0.765, sensitivity of 76.0% and specificity of 71.8%. Blood flow compensated in the left lateral and caudal lobe in the early stage of liver cirrhosis. The compensation in alcoholism in the middle and early stages is significantly higher than that of V and N cirrhosis. Iodine mixed imaging in portal phase may provide the possibility of an incremental value in segmented blood flow perfusion and functional evaluation of liver cirrhosis on a morphological basis.

A social-semantic working-memory account for two canonical language areas.

Language and social cognition are traditionally studied as separate cognitive domains, yet accumulative studies reveal overlapping neural correlates at the left ventral temporoparietal junction (vTPJ) and the left lateral anterior temporal lobe (lATL), which have been attributed to sentence processing and social concept activation. We propose a common cognitive component underlying both effects: social-semantic working memory. We confirmed two key predictions of our hypothesis using functional MRI. First, the left vTPJ and lATL showed sensitivity to sentences only when the sentences conveyed social meaning; second, these regions showed persistent social-semantic-selective activity after the linguistic stimuli disappeared. We additionally found that both regions were sensitive to the socialness of non-linguistic stimuli and were more tightly connected with the social-semantic-processing areas than with the sentence-processing areas. The converging evidence indicates the social-semantic working-memory function of the left vTPJ and lATL and challenges the general-semantic and/or syntactic accounts for the neural activity of these regions.

Periphery of porcine hepatic lobes has the smallest length density of hepatic sinusoids and bile canaliculi: A stereological histological study with implications for liver biopsies

BackgroundPorcine liver is widely used in hepatologic research as a large animal model with many anatomical and physiological similarities with humans. However, only limited information on porcine liver spatial microstructure has been published, especially regarding the hepatic sinusoids and bile canaliculi. The aim of our study was to quantify the sinusoidal and bile canalicular network in healthy male and female porcine livers and to map the variability of these structures with heterogenous distribution to improve the evaluability of liver biopsy samples. MethodsLivers from 12 healthy piglets (6 females and 6 neutered males) were sampled into 36 tissue samples per organ, representing six hepatic lobes and three different regions related to the hepatic vasculature (peripheral, paracaval and paraportal region). Histological sections were processed with a random orientation of the cutting plane. The endothelium and the bile canaliculi were stained using Ricinus communis agglutinin I lectin histochemistry. The length densities of hepatic sinusoids LV(sinusoids,liver), of bile canaliculi LV(bile canaliculi,liver) and volume fraction VV(sinusoids,liver) and surface density SV(sinusoids,liver) of sinusoids were estimated using stereological methods. The newly acquired morphometric data were compared with previously published data on density of porcine hepatocytes and fractions of connective tissue. ResultsThe peripheral region had smallest LV(sinusoids,liver), smallest LV(bile canaliculi,liver) and greatest VV(sinusoids,liver). The six hepatic lobes had statistically comparable length densities of both sinusoids and bile canaliculi, but the left lateral lobe had smallest VV(sinusoids,liver). Regions with greater LV(sinusoids,liver) had also greater LV(bile canaliculi,liver) and SV(sinusoids,liver) and were accompanied by greater density of smaller hepatocytes. Regions with smaller LV(sinusoids,liver) and LV(bile canaliculi,liver) contained a greater fraction of interlobular connective tissue. ConclusionsThe length density of hepatic sinusoids is smaller in the peripheral regions of the porcine liver than in other regions related to the hepatic vasculature – paracaval and paraportal regions, and smaller in castrated males than in females. Greater length density of liver sinusoids was linked with greater local density of bile canaliculi, with local increase in the density of smaller hepatocytes and, simultaneously, with smaller fractions of hepatic connective tissue. The intrahepatic and inter-sexual variability of the porcine liver morphology needs to be taken into account when designing and interpreting experiments involving the histological quantification of the microvascular network. The complete primary morphometric data describing the distribution of morphometric parameters within porcine liver were made available in a form facilitating the power analysis to justify the minimal number of tissue samples or animals required when designing further histological evaluation studies. The macroscopic map of microvessels and bile canaliculi variability facilitates their assessment in liver biopsies in the pig.