Assessment of first-time and repeated acute adverse reactions to gadolinium-based contrast agents in MRI: A retrospective study

PURPOSE

To identify gadolinium-based contrast agents (GBCAs)-related and patient-related risk factors for acute adverse reactions (AARs), and to examine the incidence and severity of repeated AARs.

METHODS

This study retrospectively evaluated all intravenous GBCA injections in MRI studies at a single institution from January 2012 to September 2019. First-time AARs in patients without a past history of AARs and risk factors were assessed using multivariable regression models with generalized estimating equations. For patients with a past history of AAR(s), we evaluated the incidence of repeated AARs using the Fisher's exact test, as well as the severity of these repeated AARs.

RESULTS

First-time AARs occurred in 129 of 41,827 GBCA injections (0.31 %; 0.70 % of 18,431 patients). With gadoterate meglumine as the reference, the odds ratio (OR) for allergic-like reactions to three GBCAs ranged from 3.27 to 8.03 (p = 0.012 to <0.001). For chemotoxic reactions, the OR was 3.75 (p = 0.001) for gadoteridol. Outpatients had a lower OR for chemotoxic reactions, while higher ORs were observed in head/neck and breast MRI (p < 0.05). The OR for age was 0.99 (p < 0.05). Patients with a past history of AAR(s) had a 3.6 % incidence of mild repeated AARs for all GBCA, significantly higher than the 0.31 % in first-time AARs (p < 0.001). No effectiveness was found for steroid premedication.

CONCLUSION

The occurrence of first-time AARs was related to the GBCA used and other factors. The incidence of repeated AARs was higher than first-time AARs, though all were mild in severity.

Effect of X-ray tube on image quality and pancreatic ductal adenocarcinoma conspicuity in pancreatic protocol dual-energy CT

AIM

To compare the radiation dose, image quality, and conspicuity of pancreatic ductal adenocarcinoma (PDAC) in pancreatic protocol dual-energy computed tomography (CT) between two X-ray tubes mounted in the same CT machine.

MATERIAL AND METHODS

This retrospective study comprised 80 patients (median age, 73 years; 45 men) who underwent pancreatic protocol dual-energy CT from January 2019 to March 2022 using either old (Group A, n=41) or new (Group B, n=39) X-ray tubes mounted in the same CT machine. The imaging parameters were completely matched between the two groups, and CT data were reconstructed at 70 and 40 keV. The CT dose-index volume (CTDIvol); CT attenuation of the abdominal aorta, pancreas, and PDAC; background noise; and qualitative scores for the image noise, overall image quality, and PDAC conspicuity were compared between the two groups.

RESULTS

The CTDIvol was lower in Group B than Group A (7.9 versus 9.2 mGy; p<0.001). The CT attenuation of all anatomical structures at 70 and 40 keV was comparable between the two groups (p=0.06-0.78). The background noise was lower in Group B than Group A (12 versus 14 HU at 70 keV, p=0.046; and 26 versus 30 HU at 40 keV, p<0.001). Qualitative scores for image noise and overall image quality at 70 and 40 keV and PDAC conspicuity at 40 keV were higher in Group B than Group A (p<0.001-0.045).

CONCLUSION

The latest X-ray tube could reduce the radiation dose and improve image quality in pancreatic protocol dual-energy CT.

Computed Tomography and 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography Imaging Biomarkers of Lung Invasive Non-mucinous Adenocarcinoma: Prediction of Grade 3 Tumour Based on World Health Organization Grading System

AIMS

To evaluate computed tomography (CT) and 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) findings of invasive non-mucinous adenocarcinoma (INMA) of the lung as a predictor of histological tumour grade according to 2021 World Health Organization (WHO) classification.

MATERIALS AND METHODS

This retrospective study included consecutive patients with surgically resected INMA who underwent both preoperative CT and 18F-FDG-PET/CT. A three-tiered tumour grade was performed based on the fifth edition of the WHO classification of lung tumours. CT imaging features and the maximum standardised uptake value (SUVmax) were compared among the three tumour grades.

RESULTS

In total, 214 patients with INMA (median age 70 years; interquartile range 65-76 years; 123 men) were histologically categorised: 36 (17%) as grade 1, 102 (48%) as grade 2 and 76 (35%) as grade 3. Pure solid appearance was more frequent in grade 3 (83%) than in grades 1 (0%) and 2 (26%) (P < 0.001). The SUVmax of the entire tumour was higher in grade 3 than in grades 1 and 2 (P < 0.001). Multivariable analysis revealed that pure solid appearance (odds ratio = 94.0; P < 0.001), round/oval shape (odds ratio = 4.01; P = 0.001), spiculation (odds ratio = 2.13; P = 0.04), air bronchogram (odds ratio = 0.40; P = 0.03) and SUVmax (odds ratio = 1.45; P < 0.001) were significant predictors for grade 3 INMAs.

CONCLUSION

Pure solid appearance, round/oval shape, spiculation, absence of air bronchogram and high SUVmax were associated with grade 3 INMAs. CT and 18F-FDG-PET/CT were potentially useful non-invasive imaging methods to predict the histological grade of INMAs.

Comparison of olanexidine versus povidone-iodine as a preoperative antiseptic for reducing surgical site infection in both scheduled and emergency gastrointestinal surgeries: A single-center randomized clinical trial

Aim

Surgical site infection (SSI) is one of the most common postoperative complications in gastrointestinal surgery. To clarify the superiority of 1.5% olanexidine, we conducted a randomized prospective clinical trial that enrolled patients undergoing gastrointestinal surgery with operative wound classes II-IV.

Methods

To evaluate the efficacy of 1.5% olanexidine in preventing SSIs relative to 10% povidone-iodine, we enrolled 298 patients in each group. The primary outcome was a 30-day SSI, and the secondary outcomes were incidences of superficial and deep incisional SSI and organ/space SSI. In addition, subgroup analyses were performed.

Results

The primary outcome of the overall 30-day SSI occurred in 38 cases (12.8%) in the 1.5% olanexidine group and in 53 cases (18.0%) in the 10% povidone-iodine group (adjusted risk ratio: 0.716, 95% confidence interval: 0.495-1.057, p = 0.083). Organ/space SSI occurred in 18 cases (6.1%) in the 1.5% olanexidine group and in 31 cases (10.5%) in the 10% povidone-iodine group, with a significant difference (adjusted risk ratio: 0.587, 95% confidence interval: 0.336-0.992, p = 0.049). Subgroup analyses revealed that SSI incidences were comparable in scheduled surgery (relative risk: 0.809, 95% confidence interval: 0.522-1.254) and operative wound class II (relative risk: 0.756, 95% confidence interval: 0.494-1.449) in 1.5% olanexidine group.

Conclusion

Our study revealed that 1.5% olanexidine reduced the 30-day overall SSI; however, the result was not significant. Organ/space SSI significantly decreased in the 1.5% olanexidine group. Our results indicate that 1.5% olanexidine has the potential to prevent SSI on behalf of povidone-iodine.

Contrast-induced anaphylaxis: does it occur in the medical environment and is it being responded to appropriately?

PURPOSE

To analyze the appropriateness of primary response for anaphylaxis due to iodinated contrast media (ICM) or gadolinium-based contrast agents (GBCA).

MATERIALS AND METHODS

This retrospective study included all patients in whom intravenous contrast agents (five types of ICMs and four types of GBCAs) were administered at our hospital between April 2016 and September 2021. For the patients who developed anaphylaxis, we obtained data on the time records of contrast injection, anaphylaxis onset, and intramuscular adrenaline (epinephrine) administration.

RESULTS

Of the 76,555 ICM and 30,731 GBCA administrations, anaphylaxis occurred in 49 cases (0.05%), and in 48 cases (98.0%) the onset was within 30 min after administration with widely distributed times (median, 7.5 min; interquartile range, 4.5-10.8 min; max, 26 min). Intramuscular adrenaline administration was performed in 43 cases (87.8%), and this was done within five minutes after the onset in 37 cases (75.5%). Only in 24 cases (49.0%), there were time records of both the onset and adrenaline administration (if performed).

CONCLUSION

Anaphylaxis occurred within 30 min after contrast injection in the majority of the cases, but times were widely distributed. Only in 75.5% of cases, appropriate primary treatment was performed, and the importance of keeping exact time records in patients' charts should be re-emphasized.

Clinical features and risk factors of iodinated contrast media (ICM)-induced anaphylaxis

PURPOSE

To evaluate the clinical features and risk factors of iodinated contrast media (ICM)-induced anaphylaxis.

METHODS

This retrospective study included all patients undergoing contrast-enhanced computed tomography (CT) with intravenous ICM administration (iopamidol, iohexol, iomeprol, iopromide, ioversol) at our hospital between April 2016 and September 2021. Medical records of patients who experienced anaphylaxis were reviewed, and the multivariable regression model using generalized estimating equations was employed to eliminate the effect of intrapatient correlation.

RESULTS

Of the 76,194 ICM administrations (44,099 men [58 %] and 32,095 women; age, median, 68 years) to 27, 696 patients, anaphylaxis occurred in 45 cases in 45 different patients (0.06 % of administration and 0.16 % of patients), all with onset within 30 min after administration. Thirty-one (69 %) had no risk factors for ADRs, including 14 (31 %) who had previously used the same ICM that caused anaphylaxis. Thirty-one patients (69 %) had a history of ICM use without any ADRs. Four patients (8.9 %) received oral steroid premedication. The only factor associated with anaphylaxis was the type of ICM, with an odds ratio (OR) of 6.8 (p < 0.001) for iomeprol with iopamidol as a reference. No significant differences in OR of anaphylaxis were found for patients' age, sex, or premedication.

CONCLUSION

The overall incidence of anaphylaxis due to ICM was very low. More than half of the cases had no risk factors for ADRs and had no ADRs on past ICM administration, although the ICM type was associated with a higher OR.

Reliability of ultrasound hepatorenal index and magnetic resonance imaging proton density fat fraction techniques in the diagnosis of hepatic steatosis, with magnetic resonance spectroscopy as the reference standard

PURPOSE

To evaluate the reliability of ultrasound hepatorenal index (US-HRI) and magnetic resonance imaging proton density fat fraction (MRI-PDFF) techniques in the diagnosis of hepatic steatosis, with magnetic resonance spectroscopy proton density fat fraction (MRS-PDFF) as the reference standard.

MATERIALS AND METHODS

Fifty-two adult volunteers (30 men, 22 women; age, 31.5 ± 6.5 years) who had no history of kidney disease or viral/alcoholic hepatitis were recruited to undergo abdominal US, MRI, and MRS examinations. US-HRI was calculated from the average of three pairs of regions of interest (ROIs) measurements placed in the liver parenchyma and right renal cortex. On MRI, the six-point Dixon technique was employed for calculating proton density fat fraction (MRI-PDFF). An MRS sequence with a typical voxel size of 27 ml was chosen to estimate MRS-PDFF as the gold standard. The data were evaluated using Pearson's correlation coefficient and receiver operating characteristic (ROC) curves.

RESULTS

The Pearson correlation coefficients of US-HRI and MRI-PDFF with MRS-PDFF were 0.38 (p = 0.005) and 0.95 (p<0.001), respectively. If MRS-PDFF ≥5.56% was defined as the gold standard of fatty liver disease, the areas under the curve (AUCs), cut-off values, sensitivities and specificities of US-HRI and MRI-PDFF were 0.74, 1.54, 50%, 91.7% and 0.99, 2.75%, 100%, 88.9%, respectively. The intraclass correlation coefficients (ICCs) of US-HRI and MRI-PDFF were 0.70 and 0.85.

CONCLUSION

MRI-PDFF was more reliable than US-HRI in diagnosing hepatic steatosis.

Aggressive Laparoscopic Cholecystectomy in Accordance with the Tokyo Guideline 2018

Objectives:

The Tokyo Guidelines 2018 have been widely adopted since their publication. However, the few reports on clinical outcomes following laparoscopic cholecystectomy have not taken into account the severity of the acute cholecystitis and the patient’s general condition, as estimated by the Charlson comorbidity index. This study aimed to assess the relationships between severity, Charlson comorbidity index, and clinical outcomes subsequent to laparoscopic cholecystectomy.

Methods:

We extracted the retrospective data for 370 Japanese patients who underwent emergency or scheduled early laparoscopic cholecystectomy within 72 hours from onset between February 2015 and August 2018. We compared postoperative factors in relationship to severity (grade I versus grade II/III). Then, we made a similar comparison between those with low (< 4) and high Charlson comorbidity index (≥ 4).

Results:

According to the Tokyo guideline 2018 levels of severity, there were 282 (76.2%), 61 (16.5%), and 27 (7.3%) patients in grades I, II, and III, respectively. With regards to surgical outcomes, the mean operating time was 62.3 minutes and the mean blood loss was 24.4 mL. The mean hospital stay was 3.6 days, with no mortalities. Blood loss was the only factor affected by severity (20.9 mL versus 60.1 mL, P = 0.0164), and operating time was the only factor affected by high Charlson comorbidity index (53.4 versus 67.8 minutes, P = 0.0153).

Conclusion:

Our aggressive strategy is acceptable, and severity and Charlson comorbidity index are not critical factors suggesting the disqualification of early laparoscopic cholecystectomy in patients with any grade acute cholecystitis.

Rare presentation of De Garengeot hernia treated by transabdominal preperitoneal hernia repair: A case report

We present a rare case of De Garengeot hernia treated with simultaneous laparoscopic appendectomy and transabdominal preperitoneal hernia repair. Our patient was an 85-year-old man with a bulging mass in the right groin. De Garengeot hernia was observed on contrast-enhanced CT. Urgent laparoscopy showed the distal part of the appendix passing through a right-sided femoral hernia. Laparoscopic appendectomy was performed, followed by transabdominal preperitoneal repair of the femoral hernia. Pathological examination revealed ischemic necrosis of the appendix. The patient's postoperative recovery was uneventful.

AB0056 TNFR2 PROMOTES INFLAMMATORY PROGRAMS IN FIBROBLAST-LIKE SYNOVIOCYTES

Background:

TNF-mediated fibroblast-like synoviocyte (FLS) activation is important for inflammation and joint destruction in rheumatoid arthritis (RA). The role of TNF-receptor 1 (TNFR1) in FLS activation has thoroughly been characterized. The functions of TNFR2 are, however, largely unknown.

Objectives:

To investigate the contribution of TNFR2 to the TNF-mediated activation of FLS.

Methods:

RA-FLS were transfected with TNFR2-targeting siRNA pools and transcriptional changes were determined by RNA-seq. QPCR, ELISA and immunoblotting were used to confirm the RNA-seq results and to gain insights into the pathways that regulate TNFR2-mediated changes in FLS.

Results:

TNF stimulation of FLS resulted in a strong upregulation of proinflammatory cytokines, chemokines, tissue-degrading enzymes and other genes that are associated with synovial inflammation in RA. Silencing of TNFR2 markedly diminished the TNF-response of RA-FLS. Especially, “interferon”-stimulated-genes (ISGs) including putative master regulators of joint inflammation, such as the CXCR3 chemokines CXCL9, CXCL10 and CXCL11 were affected by the knockdown of TNFR2. Consistently, immunoblots showed that TNFR2 was required for the TNF-induced phosphorylation of the transcription factor STAT1, which is known to mediate the transcription of ISGs, such as CXCR3 chemokines.

Conclusion:

TNFR2 regulates proinflammatory gene expression in RA-FLS via STAT1 and thereby contributes to the detrimental effects of TNF in synovial joint inflammation.

Disclosure of Interests:

None declared

Deep-learning-based image reconstruction in dynamic contrast-enhanced abdominal CT: image quality and lesion detection among reconstruction strength levels

AIM

To evaluate the use of deep-learning-based image reconstruction (DLIR) algorithms in dynamic contrast-enhanced computed tomography (CT) of the abdomen, and to compare the image quality and lesion conspicuity among the reconstruction strength levels.

MATERIALS AND METHODS

This prospective study included 59 patients with 373 hepatic lesions who underwent dynamic contrast-enhanced CT of the abdomen. All images were reconstructed using four reconstruction algorithms, including 40% adaptive statistical iterative reconstruction-Veo (ASiR-V) and DLIR at low, medium, and high-strength levels (DLIR-L, DLIR-M, and DLIR-H, respectively). The signal-to-noise ratio (SNR) of the abdominal aorta, portal vein, liver, pancreas, and spleen and the lesion-to-liver contrast-to-noise ratio (CNR) were calculated and compared among the four reconstruction algorithms. The diagnostic acceptability was qualitatively assessed and compared among the four reconstruction algorithms and the conspicuity of hepatic lesions was compared between <5 and ≥5 mm lesions.

RESULTS

The SNR of each anatomical structure (p<0.0001) and CNR (p<0.0001) were significantly higher in DLIR-H than the other reconstruction algorithms. Diagnostic acceptability was significantly better in DLIR-M than the other reconstruction algorithms (p<0.0001). The conspicuity of hepatic lesions was highest when using 40% ASiR-V and tended to lessen as the reconstruction strength level was getting higher in DLIR, especially in <5 mm lesions; however, all hepatic lesions could be detected.

CONCLUSIONS

DLIR improved the SNR, CNR, and image quality compared with 40% ASiR-V, while making it possible to decrease lesion conspicuity using higher reconstruction strength.

Cerebral Microbleeds, Cerebrospinal Fluid, and Neuroimaging Markers in Clinical Subtypes of Alzheimer's Disease

Lobar cerebral microbleeds (CMBs) in Alzheimer's disease (AD) are associated with cerebral amyloid angiopathy (CAA) due to vascular amyloid beta (Aβ) deposits. However, the relationship between lobar CMBs and clinical subtypes of AD remains unknown. Here, we enrolled patients with early- and late-onset amnestic dominant AD, logopenic variant of primary progressive aphasia (lvPPA) and posterior cortical atrophy (PCA) who were compatible with the AD criteria. We then examined the levels of cerebrospinal fluid (CSF) biomarkers [Aβ1-42, Aβ1-40, Aβ1-38, phosphorylated tau 181 (P-Tau), total tau (T-Tau), neurofilament light chain (NFL), and chitinase 3-like 1 protein (YKL-40)], analyzed the number and localization of CMBs, and measured the cerebral blood flow (CBF) volume by ^99mTc-ethyl cysteinate dimer single photon emission computerized tomography (^99mTc ECD-SPECT), as well as the mean cortical standard uptake value ratio by ¹¹C-labeled Pittsburgh Compound B-positron emission tomography (¹¹C PiB-PET). Lobar CMBs in lvPPA were distributed in the temporal, frontal, and parietal lobes with the left side predominance, while the CBF volume in lvPPA significantly decreased in the left temporal area, where the number of lobar CMBs and the CBF volumes showed a significant inversely correlation. The CSF levels of NFL in lvPPA were significantly higher compared to the other AD subtypes and non-demented subjects. The numbers of lobar CMBs significantly increased the CSF levels of NFL in the total AD patients, additionally, among AD subtypes, the CSF levels of NFL in lvPPA predominantly were higher by increasing number of lobar CMBs. On the other hand, the CSF levels of Aβ1-38, Aβ1-40, Aβ1-42, P-Tau, and T-Tau were lower by increasing number of lobar CMBs in the total AD patients. These findings may suggest that aberrant brain hypoperfusion in lvPPA was derived from the brain atrophy due to neurodegeneration, and possibly may involve the aberrant microcirculation causing by lobar CMBs and cerebrovascular injuries, with the left side dominance, consequently leading to a clinical phenotype of logopenic variant.

Post-contrast Acute Kidney Injury Following Emergency Transcatheter Arterial Embolization for Uncontrollable Postpartum Hemorrhage

The aim of this study was to investigate the incidence of post-contrast acute kidney injury (PC-AKI) in patients with uncontrollable postpartum hemorrhage undergoing emergency transcatheter arterial embolization (TAE). Data collected included patient characteristics, serum creatinine (SCr) level before and after TAE, iodine quantity of contrast media, time between computed tomography and TAE, diabetes mellitus, hemorrhage volume, and blood transfusion volume. For the diagnosis of PC-AKI, the criteria of the European Society of Urogenital Radiology Guidelines (version 10.0) were used. A total of 71 TAE procedures were performed over a 5-year period, and 47 patients met the inclusion criteria. Preprocedural renal function and change of SCr were positively correlated (P < .001), although no patients met the PC-AKI criteria and none showed renal impairment on the follow-up examination (95% upper confidence limit = 6.2%). Total iodine quantity was not correlated with SCr change. Postpartum hemorrhage was finally controlled in all 47 patients, and they were subsequently discharged. In conclusion, emergency TAE for patients with uncontrollable postpartum hemorrhage was a safe and effective procedure, not only in terms of bleeding-related and other outcomes but also with respect to the risk of PC-AKI.

Indocyanine green fluorescence imaging via endoscopic nasal biliary drainage during laparoscopic deroofing of liver cysts

Laparoscopic deroofing of liver cysts is widely accepted as the treatment of symptomatic huge liver cysts. As bile leakage is a common complication of this procedure, indocyanine green (ICG) imaging has played an active role in detecting intrahepatic biliary tract. However, infusion ICG imaging needs time rag after injection due to moving from bloodstream to bile, and also, additional injection is needed when the fluorescent imaging is not clear. To cover this weakness of ICG imaging, we first applied ICG imaging via 5-Fr endoscopic nasal biliary drainage (ENBD) during laparoscopic deroofing of liver cysts. This technique promptly gives us ICG imaging after ICG injection from ENBD; in addition, direct ICG imaging sometimes reveals minor leakage from sealing line and staple lines; therefore, we believe that direct ICG imaging via ENBD helps us to prevent post-operative bile leakage.

The effect of abolishing instructions to fast prior to contrast-enhanced CT on the incidence of acute adverse reactions

OBJECTIVES

To evaluate the effect of abolishing instructions to fast prior to contrast-enhanced CT on acute adverse reactions (AARs).

METHODS

In our institution, we instructed patients to fast one meal before contrast-enhanced CT examinations. However, we abolished these instructions at the end of March 2019, and solid food intake was not restricted before contrast-enhanced CT after this date. The differences in the incidence of AARs before (December 2015-November 2018, n = 43,927) and after (April 2019-March 2020, n = 14,676) abolishing instructions to fast were compared. We allowed 4 months (December 2018-March 2019) for this policy change to fully permeate the CT referrals. The medical records of patients who vomited were retrospectively reviewed by one of the authors for notations of aspiration or aspiration pneumonia attributable to vomiting.

RESULTS

The overall incidence of AARs before (1.60%, n = 705) and after abolition (1.40%, n = 205) did not change significantly. As the chemotoxic reactions, the incidence of nausea decreased significantly (0.31 to 0.18%, p = 0.006). The incidence of vomiting did not change (0.12 to 0.16%), and there were no cases of aspiration pneumonia attributable to vomiting during the study period. The incidence of severe hypersensitivity/allergy-like reactions did not change (0.06 to 0.05%).

CONCLUSIONS

Abolishing instructions to fast decreased the incidence of nausea, but did not affect the incidence of vomiting. No cases of aspiration pneumonia attributable to vomiting were found. Our study confirmed that fasting is not required prior to contrast-enhanced CT.

Two-stage laparoscopic surgery for incarcerated umbilical Littre's hernia in severely obese patient: a case report

Background

Littre's hernia containing Meckel's diverticulum is an extremely rare disease. We report an adult case of two-stage laparoscopic surgery for incarceration of Meckel's diverticulum in an umbilical hernia.

Case presentation

The case involved a 23-year-old, severely obese man with BMI 36.5 kg/m². After experiencing effusion from the umbilicus for 2 months, and was referred from a local dermatologist. We diagnosed an infected urachal remnant, and antibiotic therapy was performed first. Surgery was planned for after the infection disappeared. During follow-up, effusion from the umbilicus took on an intestinal fluid-like character, so we diagnosed small intestinal cutaneous fistula and performed surgery. Under laparoscopy, we found a Meckel's diverticulum incarcerated in an umbilical hernia. The diverticulum was resected first, and the incarceration was released. The umbilicus was infected, so we planned repair of the umbilical hernia in a second surgery. The postoperative course was uneventful and the patient was discharged on postoperative day 5. One month after the initial operation, we confirmed that there were no signs of infection, and performed umbilical hernia repair using the laparoscopic intraperitoneal onlay mesh (IPOM) repair. Postoperative progress was uneventful and he was discharged on postoperative day 4. No recurrence or infection was observed until 8 months postoperatively.

Conclusions

We performed dissection of the diverticulum and umbilical hernia repair for the incarcerated umbilical Littre's hernia under laparoscopy in a severely obese patient. The risk of mesh infection seems to be avoidable using a two-stage surgery, and the risk of recurrence can be reduced using the IPOM repair compared with simple suture closure.

Needlescopic surgery for large umbilical hernia in a patient with morbid obesity using intraperitoneal onlay mesh with fascial defect closure: a case report

Background

The European and American guidelines recommend that symptomatic umbilical hernias (UHs) are repaired using an open approach with a preperitoneal flat mesh. However, the standard treatment procedure for large UH in patients with extreme obesity is yet to be established. Here, we present the first case of a patient with morbid obesity undergoing laparoscopic UH repair using needlescopic instruments and an intraperitoneal onlay mesh plus repair (IPOM plus).

Case presentation

A 29-year-old man, who was classified as morbidly obese (body mass index, 36.7 kg/m²) noticed a reducible nontender mass in the umbilical region and was subsequently diagnosed with an UH, with a diameter of 4 cm. Laparoscopic IPOM plus repair was planned using a needlescopic method for a large UH in the patient with morbid obesity. A 3-mm rigid laparoscope was mainly used in the procedure. After a 12-mm trocar and two 3-mm trocars were inserted, fascial defect closure was performed using intracorporeal suturing with 0 monofilament polypropylene threads. Then, IPOM was performed laparoscopically using an 11.4-cm round mesh coated with collagen to prevent adhesions. The operative time and blood loss were 57 min and 1 g, respectively. The postoperative course was uneventful.

Conclusions

Reduced-port laparoscopic surgery using needlescopic instruments and an IPOM plus technique is a minimally invasive and convenient combination option for large UH in a patient with morbid obesity.

[Improved Neural Imaging Sequence and Comparison with Conventional Methods]

The purpose of this study was to improve the contrast between the nerves and blood by reconsidering the imaging parameters of the sampling perfection with application-optimized contrasts using different flip angle evolutions (SPACE) method, and to compare it with conventional methods, including the constructive interference in steady state (CISS) and T₂-weighted SPACE (T2-SPACE) methods. In the phantom study, the repetition time (TR), echo time (TE), flip angle (FA), and turbo factor (TF) of SPACE were varied using the restore pulse. The parameters for which the nerve-blood contrast (C1) and cerebrospinal fluid-nerve contrast (C2) were equal were selected. Though multiple conditions resulted in C1 and C2 equivalence, we determined/set the TR=500 ms, TE=21 ms,  FA=120°, and  TF=30, considering the acquisition time, specific absorption rate (SAR), and artifacts. This sequence was called "short TR and short TE SPACE with restore pulse (SSSR)". In the phantom and healthy volunteer studies, the contrast between the nerves and blood in the SSSR method was statistically superior in both the physical and visual assessments compared with conventional methods. In the healthy volunteer study, C1 improved from 0.08 for CISS and 0.18 for T2-SPACE to 0.43 for SSSR. This is because the nerve signals in conventional methods were low due to the heavy T₂-weighted, while those in the SSSR method were high due to the short TE and effect of the restore pulse. In conclusion, the contrast between the nerves and blood was significantly higher in the SSSR method compared with conventional methods.

Evaluation of a Correction Method for 111In-Pentetreotide SPECT Imaging of Gastroenteropancreatic Neuroendocrine Tumors

The number of patients with the extremely rare disease gastroenteropancreatic (GEP) neuroendocrine tumor (NET) has increased rapidly in recent years. ¹¹¹In-pentetreotide SPECT in somatostatin receptor scintigraphy has been used for the assessment of GEP NET patients. To diagnose GEP NET, appropriate selection of image correction parameters is critical. Correction methods may improve the ¹¹¹In-pentetreotide SPECT image quality, but there is currently no standard technique. The purpose of this study was to determine the optimal correction parameter settings for ¹¹¹In-pentetreotide SPECT. Methods: A phantom study produced images with a tumor-to-background ratio of as high as 16:1. A triple energy window was used for scatter correction (SC), and attenuation correction (AC) was CT-based. Correlation analysis was performed in 4 groups: no correction (NC), SC, AC, and combined SC with AC (CC). The ¹¹¹In-pentetreotide SPECT results for 20 randomly selected patients (13 men and 7 women; age range, 37-81 y) with confirmed GEP NET were analyzed using data collected 4 h after injection of 111 MBq of ¹¹¹In-pentetreotide. Emission data were reconstructed using ordered-subset expectation maximization (OSEM) with different settings. Different combinations of the correction parameters were used to analyze the contrast-to-noise ratios (CNRs) obtained with the phantom. In the clinical study, 20 GEP NET patients were used to evaluate the GEP NET lesion CNR by 4 different image correction methods obtained from ¹¹¹In-pentetreotide SPECT images: NC, SC, AC, and CC. NC was used as a reference method. Results: The phantom study revealed that the optimal energy window in the photopeak for somatostatin receptor scintigraphy was 171 keV ± 10% and 245 keV ± 7.5%, and the optimal OSEM reconstruction conditions were 8 subsets and 6 iterations. Among the OSEM collection conditions, CC produced a significantly higher CNR than NC or SC (P < 0.05). In the clinical study, CC was found to increase the CNR (P < 0.05). Conclusion: CC improves the correction in ¹¹¹In-pentetreotide SPECT studies, compared with NC, providing better contrast and sharper outlines of lesions and organs.

Deep White Matter Lesions Are Associated with Early Recognition of Dementia in Alzheimer's Disease

Neuroimages of cerebral amyloid-β (Aβ) accumulation and small vessel disease (SVD) were examined in patients with various types of cognitive disorders using 11C-labeled Pittsburgh Compound B-positron emission tomography (PiB-PET) and magnetic resonance imaging (MRI). The mean cortical standardized uptake value ratio (mcSUVR) was applied for a quantitative analysis of PiB-PET data. The severity of white matter lesions (WML) and enlarged perivascular spaces (EPVS) on MRI were assessed to evaluate complicating cerebral SVD using semiquantitative scales. In homozygous apolipoprotein E ɛ3/ɛ3 carriers, the incidence of more severe WML and EPVS was higher in PiB-positive than PiB-negative patients, indicating that WML and EPVS might be associated with enhanced Aβ accumulation. An association study between PiB-PET and MRI findings revealed that higher WML grades significantly correlate with lower mcSUVRs, especially in the frontal area, indicating that more severe ischemic MRI findings are associated with milder Aβ accumulation among patients with Alzheimer's disease. In these patients SVD may accelerate the occurrence of cognitive decline and facilitate early recognition of dementia.

Intraperitoneal onlay mesh repair (IPOM) plus technique using a hybrid procedure of open laparotomy and laparoscopic approach (hybrid IPOM plus) for incarceration of umbilical hernia in a severely obese patient: a case report

Background

A standard procedure for the treatment of incarcerated umbilical hernia among severely obese patients has yet to be established. We used the hybrid intraperitoneal onlay mesh repair (IPOM) plus method, which combines open and laparoscopic surgery to treat incarcerated umbilical hernia in a severely obese patient.

Case presentation

A 46-year-old man presented in our department with a chief complaint of a painful mass in the umbilical region. Incarcerated umbilical hernia was diagnosed on the basis of abdominal computed tomography, and the decision was made to perform emergency surgery. The patient was severely obese (body mass index, 53.8 kg/m²), and the incarcerated portion of the hernia was therefore first addressed by open surgery. As bowel resection was unnecessary, the risk of infection was considered low, and after direct closure of the hernia orifice, IPOM was performed laparoscopically using the hybrid IPOM plus method.

Conclusion

Among severely obese patients, first trocar insertion is difficult and the wound site tends to come under strain, meaning that simple closure of the hernia orifice results in a high recurrence rate. The hybrid IPOM plus method used in this case combines open surgery and laparoscopy and appears useful for treating uninfected incarcerated umbilical hernia in severely obese patients safely and with an anticipated low rate of postoperative recurrence.

Improvement of diagnostic accuracy of Parkinson's disease on I-123-ioflupane single photon emission computed tomography (123I FP-CIT SPECT) using new Japanese normal database

OBJECTIVES

I-123-ioflupane single photon emission computed tomography (FP-CIT-SPECT) has been used to assess dopamine transporter (DAT) loss in Parkinson's disease. The specific binding ratio (SBR), a quantitative parameter of DAT density in the striatum, may be affected by differences in age, sex, and SPECT system. The purpose of this study was to evaluate the utility of FP-CIT-SPECT using the Japanese normal database (NDB) in the diagnosis of Parkinson's disease.

METHODS

To standardize the quantitative outcome measures of DAT density obtained with different SPECT systems, striatal phantoms filled with striatal to background materials at ratios between 8:1 and 1:1 were measured using a gamma camera (ECAM) in our institute. Consecutive fifty patients (23 men and 27 women; age range, 40-86 years) with suspected PD undergoing FP-CIT SPECT brain imaging during the period from April to October 2016 were enrolled in this retrospective study. Their final diagnoses were PD in 28 patients and PD in 22 patients. SBRs of the patients were calculated using either new (Japanese database with different age and sex; NEWver) or old (non-Japanese database not specifying age and sex; OLDver) version software (AZE Virtual Place Hayabusa [DaTView], AZE, Ltd. Tokyo, Japan). The McNemar test was used to compare the diagnostic accuracy between old and new versions.

RESULTS

Based on the phantom study, the calibrated SBR could be calculated by Y=1.25×Measured SBR+0.78. The sensitivities for OLDver and NEWver were 100% and 93%, respectively (p=0.5), and the specificities were 55% and 100% (p=0.002). The diagnostic accuracy of NEWver (96%) was better than that of OLDver (80%, p<0.001).

CONCLUSION

FP-CIT-SPECT using the Japanese NDB improved the diagnostic accuracy of PD by improving specificity.

Cardiopulmonary Impairments Caused by a Large Hiatal Hernia with Organoaxial Gastric Volvulus Showing Upside-Down Stomach: A Case Report

Patient: Female, 74

Final Diagnosis: Hiatal hernia with gastric volvulus

Symptoms: Dyspena

Medication: —

Clinical Procedure: —

Specialty: Surgery

Axillary lymph-node metabolic activity assessment on 18F-FDG-PET/CT in rheumatoid arthritis patients treated with biologic therapies

Objective: Recent studies have provided new insights into the role of lymph nodes (LNs) in rheumatoid arthritis (RA). The aim of this study was to evaluate the metabolic activity of the axillary LNs in relation to that of the upper limb joints and the clinical assessment of disease activity in RA patients treated with biologic therapies.Method: ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) scans were acquired for 64 patients with RA at baseline and after 6 months of biologic therapy, and the patients' clinical status was evaluated. The maximum standardized uptake value (SUV_max), metabolic active volume, and total lesion glycolysis (TLG) were used to assess glucose metabolism in the LNs and 12 joints. Clinical evaluations included serum markers and the Disease Activity Score based on 28-joint count-erythrocyte sedimentation rate (DAS28-ESR).Results: Changes in the SUV_max and TLG for the axillary LNs correlated significantly with those of the ipsilateral wrist joints. There was a positive correlation between the changes in the three metabolic parameters of the axillary LNs and the changes in disease activity after treatment. After 6 months of biologic therapy, all metabolic parameters for the axillary LNs in patients with a DAS28-ESR < 3.2 were significantly lower than those of patients with a DAS28-ESR ≥ 3.2.Conclusion: A relationship between the glucose metabolism of the axillary LNs and the ipsilateral wrist joints was demonstrated by the ¹⁸F-FDG-PET/CT parameters. The metabolic activity and active volume of axillary LNs may reflect the therapeutic response to the biologic treatment of RA.

Potential Pitfalls of Diaphragm Structural Matching in Carbon-ion Radiotherapy for Pancreatic Cancer

BACKGROUND/AIM

To evaluate the effectiveness of diaphragm matching (DM) for carbon-ion radiotherapy (CIRT) of pancreatic cancer patients and develop a simple method to estimate tumour position.

PATIENTS AND METHODS

Treatment planning CTs from 27 pancreatic cancer patients treated with CIRT in our facility were used in this study, and 32 other CT image datasets taken on different days were used for measuring tumour and diaphragm displacements. A correction method (SI-correction) was developed using the coefficient x of the regression line formula for the displacements between the diaphragm and tumour in the superior-inferior direction. The tumour positioning errors of bone matching (BM), DM, and SI-correction were measured.

RESULTS

Mean (±standard deviation) absolute errors of BM, DM, and SI-correction were 5.10±3.31, 7.48±4.04, and 4.13±2.51 mm, respectively. DM showed significant differences compared to the other correction methods.

CONCLUSION

DM was subject to larger errors than BM. Our correction method improved positional errors.

Retrospective case-matched study between reduced port laparoscopic rectopexy and conventional laparoscopic rectopexy for rectal prolapse

Introduction:

Reduced port laparoscopic Well's procedure (RPLWP) is a novel technique used to overcome the limitations of single-incision laparoscopic surgery. The aim of this study was to compare outcomes between RPLWP and conventional laparoscopic Well's procedure (CLWP) and to investigate the learning curve of RPLWP.

Patients and Methods:

From January 2006 to March 2017, a retrospective review of a prospectively maintained laparoscopic surgery database was performed to identify patients had undergone CLWP and RPLWP. From these patients, each of 10 cases were manually matched for age, sex, body mass index. From January 2006 to March 2015, CLWP was used for all procedures whereas, from April 2015, RPLWP was routinely performed as a standard procedure for rectal prolapse.

Results:

No significant differences were observed between the two groups in terms of operating time, blood loss, intraoperative complications, and conversion to CLWP or open rectopexy. Based on the postoperative outcomes, the hospital stay was significantly shorter in the RPLWP group. The estimated learning curve for RPLWP was fitted and defined as y = 278.47^e-0.064x with R²= 0.838; therefore, a significant decrease in operative time was observed by using the more advanced surgical procedure.

Conclusions:

RPLWP is an effective, safe, minimally invasive procedural alternative to CLWP with no disadvantage for patients when a skilled surgeon performs it.

Comparison of Single-Incision Laparoscopic Cholecystectomy versus Needlescopic Cholecystectomy: A Single Institutional Randomized Clinical Trial

BACKGROUND

Both single-incision laparoscopic cholecystectomy (SILC) and needlescopic cholecystectomy (NSC) are superior to conventional laparoscopic cholecystectomy in terms of cosmetic outcome and incisional pain. We conducted a prospective, randomized clinical trial to evaluate the surgical outcome, postoperative pain, and cosmetic outcome for SILC and NSC procedures.

METHODS

In this trial, 105 patients were enrolled (52 in the SILC group; 53 in the NSC group). A visual analogue scale (VAS) was used to evaluate the cosmetic outcome and incisional pain for patients. Logistic regression analyses were used to evaluate the operative difficulty that was present for both procedures.

RESULTS

There were no significant differences in patient characteristics or surgical outcomes, including operative time and blood loss. The mean VAS scores for cosmetic satisfaction were similar in both groups. There were significant differences in the mean VAS scores for incisional pain on postoperative day 1 (p = 0.009), and analgesics were required within 12 h of surgery (p = 0.007). Obesity (body mass index ≥25 kg/m2) was the only significant influential factor for operating time over 100 min (p = 0.031).

CONCLUSION

NSC is superior to SILC in terms of short-term incisional pain. Experienced laparoscopic surgeons can perform both SILC and NSC without an increase in operative time.

[Exposure Dose Reduction for Radiologists with Combination of Angular Beam Modulation and Radiation Protection Drape in CT Fluoroscopy: A Phantom Study]

PURPOSE

To assess the dose reduction of radiologists by using angular beam modulation (ABM) and radiation protection drape during computed tomography (CT) fluoroscopy.

MATERIALS AND METHODS

The phantom was set on the lower that is 15 cm from the isocenter position. We measured the radiation exposure around the phantom with radiophotoluminescence glass dosimeters. The space radiation dose rate was measured with an ionization chamber dosimeter in the CT room.

RESULTS

The dose rate of finger radiation exposure was 67% at assumed assist tool position with ABM. And the dose rate of finger radiation exposure with the combination of ABM and radiation protection drape was 33%. The space dose rate of exposure with the combination of ABM and radiation protection drape was 49% at 150 cm.

CONCLUSION

The combination of ABM and radiation protection drape can reduce finger radiation exposure at assumed assist tool position. The space dose rate of the standing position of radiologists can get a clear dose of radiation reduction by the combination of both.

[Injection Pressure Evaluation of the New Venous Catheter with Side Holes for Contrast-enhanced CT/MRI]

The simulation study was conducted for the new venous catheter with side holes of contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) to evaluate the infusion pressure on four contrast media and several injection speeds. All infusion pressure of the new venous catheter with side holes were less than 15 kg/cm² as limitation of extension tube and also reduced the infusion pressure by 15% at the maximum compared to the catheter with single hole. The results suggest that the new venous catheter with side holes can reduce the infusion pressure by power injection of contrast-enhanced CT and MRI.

[Comparison of Analytical Values in Diffusion Kurtosis Imaging among Different MRI Units]

Diffusion kurtosis imaging (DKI) is a method of analyzing restricted diffusion. Mean kurtosis (MK) is obtained from DKI. It is not known how different MRI scanners and coil systems will change MK when the same imaging parameters are used. The purpose of this study is to identify tendencies in MK when using various MRI scanners and coil systems. A total of 27 healthy volunteers were enrolled in this study. DKI was performed on the brain for each volunteer on five MRI scanner/coil system combinations using the same scan parameters. MK of 10 anatomical areas of the brain were compared, and the signal-noise ratios (SNRs) of b-2000 s/mm² images were measured in identical areas. There were no significant differences among MKs from multi transmit (MT) MRI systems, but MK was significantly lower on the single transmit MRI system because of pepper artifact caused by low SNR. In conclusion, we found no significant differences in MK among MT systems, and MK was significantly lower without MT.

Sensation of smell and taste during intravenous injection of iodinated contrast media in CT examinations

OBJECTIVE

To assess the incidence and types of sensation of smell and taste during i.v. injection of five kinds of contrast media (CM) in CT examinations.

METHODS

735 patients who underwent contrast-enhanced CT (CE-CT) between 14 March 2016 and 5 April 2016 were enrolled. Medical staff asked patients whether they felt heat sensation and sensation of smell and taste during i.v. injection of CM (one of the following: iopromide, iomeprol, iopamidol, iohexol and ioversol) after their CE-CT. If the patients stated having felt the sensation of smell or taste, they were also asked what kind of smell or taste they sensed. Next, 30 ml of each CM was poured into high-purity pet cups for radiological technologists to smell directly. Radiological technologists were asked whether or not each CM had any smell.

RESULTS

The sensations of smell and taste incidence for iopromide were 24.3% and 18.9%, respectively, which were significantly higher than those for other CM (p < 0.05). The highest incidence of the sensation of smell was medicine-ish, and the most frequently noted taste was bitterness. All radiological technologists could directly smell only iopromide, which has an ether group on a side chain and fewer hydroxyl groups.

CONCLUSION

Iopromide showed a higher incidence of sensation of smell and taste than other CM. Advances in knowledge: This was the first investigation of sensation of smell and taste during i.v. injection of CM, and a specific CM showed a higher incidence, which is suspected to be due to its chemical structure.

Supraspinal actions of nociceptin/orphanin FQ, morphine and substance P in regulating pain and itch in non-human primates

BACKGROUND AND PURPOSE

Nociceptin/orphanin FQ (N/OFQ) peptide (NOP) receptor agonists display a promising analgesic profile in preclinical studies. However, supraspinal N/OFQ produced hyperalgesia in rodents and such effects have not been addressed in primates. Thus, the aim of this study was to investigate the effects of centrally administered ligands on regulating pain and itch in non-human primates. In particular, nociceptive thresholds affected by intracisternal N/OFQ were compared with those of morphine and substance P, known to provide analgesia and mediate hyperalgesia, respectively, in humans.

EXPERIMENTAL APPROACH

Intrathecal catheters were installed to allow intracisternal and lumbar intrathecal administration in awake and unanaesthetized rhesus monkeys. Nociceptive responses were measured using the warm water tail-withdrawal assay. Itch scratching responses were scored from videotapes recording behavioural activities of monkeys in their home cages. Antagonist studies were conducted to validate the receptor mechanisms underlying intracisternally elicited behavioural responses.

KEY RESULTS

Intracisternal morphine (100 nmol) elicited more head scratches than those after intrathecal morphine. Distinct dermatomal scratching locations between the two routes suggest a corresponding activation of supraspinal and spinal μ receptors. Unlike intracisternal substance P, which induced hyperalgesia, intracisternal N/OFQ (100 nmol) produced antinociceptive effects mediated by NOP receptors. Neither peptide increased scratching responses.

CONCLUSIONS AND IMPLICATIONS

Taken together, these results demonstrated differential actions of ligands in the primate supraspinal region in regulating pain and itch. This study not only improves scientific understanding of the N/OFQ-NOP receptor system in pain processing but also supports the therapeutic potential of NOP-related ligands as analgesics.

Laparoscopic umbilical hernia repair in a cirrhotic patient with a peritoneovenous shunt

A 62-year-old Japanese woman who had developed massive cirrhotic ascites was referred to our hospital for a peritoneovenous shunt implant. However, CT examination revealed an umbilical hernia that had not been observed before the peritoneovenous shunt was implanted. We decided to perform laparoscopic umbilical hernia repair to keep carbon dioxide from flowing backward into the central circulatory system. We first clamped the catheter and set the upper limit of the pneumoperitoneum pressure to 6 mmHg. The central venous pressure was also measured simultaneously. Mesh was then applied over the hernia and fixed by the double-crown technique. Finally, 1000-mL physiological saline was infused into the abdominal cavity while the pneumoperitoneum was slowly released. In this case, we safely performed laparoscopic umbilical hernia repair while making some alterations, specifically catheter clamping, reducing pneumoperitoneum pressure, monitoring central venous pressure, and infusing physiological saline.

[Efficacy and safety of panitumumab for K-ras wild-type unresectable or recurrent colorectal cancer - a study focusing on first-line treatment]

Panitumumab was approved in June 2010 for use in the treatment of unresectable advanced/recurrent colorectal cancer. Here, we report outcomes and adverse events of panitumumab combination therapy or single-agent chemotherapy for K-ras wild-type unresectable or recurrent colorectal cancers. Our study focused on first-line treatments. The study involved 18 patients who started receiving panitumumab in October 2010. Nine patients received panitumumab as a first-line treatment; 4, as a second-line treatment; and 5, as a third-line or subsequent treatment. The overall response rate was 27.8%. Among the patients who received panitumumab as a first-line treatment, the response rate was 55.6%. Grade 1 and 2 skin disorders were common adverse events. Grade 2 interstitial pneumonia was observed in 1 patient(5.6%). Grade 3 or higher events comprised peripheral neuropathy in 1 patient(5.6%)and neutropenia in another patient(5.6%). The treatment was beneficial, and metastatic foci were resected in 3 patients. In this study, the only adverse events of Grade 3 or higher were 1 case each of peripheral neuropathy and neutropenia. Accordingly, adequate control seemed possible. The specific line of treatment that panitumumab should belong to remains controversial. However, active initiation as first-line treatment should be considered for cases in which resection of metastatic foci can be expected from tumor reductions due to panitumumab.

Effects of changes in adipocyte hormones and visceral adipose tissue and the reduction of obesity-related comorbidities after laparoscopic sleeve gastrectomy in Japanese patients with severe obesity

The aim of this study was to evaluate the relative contribution of serum adipokines and adipokines from the patient's omentum-derived adipocytes (PODAs) and visceral adipose tissue (VAT) of Japanese patients with severe obesity. Secondarily, we analyzed patients' metabolic changes after laparoscopic sleeve gastrectomy (LSG). Twenty-three LSG patients and 23 non-obese patients undergoing elective abdominal surgery were enrolled. The levels of adipokines in the serum and the PODAs were measured. The clinical and metabolic data were evaluated at 6 months after LSG. The mean serum leptin levels and the mean serum plasminogen activator inhibitor type-1 (PAI-1) levels were significantly greater (p < 0.001) and the mean adiponectin levels were significantly lower in the LSG group (p = 0.006). In the measurements of the PODAs, the mean leptin levels (p < 0.001) were significantly greater and the mean adiponectin levels (p < 0.001) were significantly lower in the LSG group. The mean BMI (-12 kg/m², p < 0.001) and mean VAT (-135.5 cm², p = 0.001) were significantly decreased after LSG. In nine patients with type 2 diabetes mellitus, the reduction in VAT correlated with the change in high-sensitivity C-reactive protein (p = 0.006) and the homeostasis model of assessment of insulin resistance (p = 0.001). After 6 months, LSG markedly improved most obesity-related comorbidities. Our results suggest that LSG may contribute to VAT reduction, improved adipocyte hormone levels, and changes in gut physiology and endocrinology.

Laparoscopic excision of retroperitoneal tumors: report of three cases

Retroperitoneal neural tumors are rarely excised laparoscopically, with fewer than ten cases reported in the literature. Between February 2005 and December 2007, we performed successful planned laparoscopic excision of retroperitoneal tumors using the four-trocar technique in three patients. All three patients were women, with a mean age of 40.7 years. The mean tumor size was 4.8 cm. The mean operative time was 126 min and the mean blood loss 14.3 ml. The postoperative pathological diagnosis was schwannoma in one patient and ganglioneuromas in two. There was no morbidity or mortality. Although difficult to diagnose preoperatively, neural tumors in the retroperitoneal space are most often benign, with a good prognosis. Laparoscopic surgical techniques for retroperitoneal tumors are safe, and their use is encouraged when an appropriate diagnosis is made, after exclusion of malignant subtypes.