Improvement in gait velocity variability after cerebrospinal fluid elimination and its relationship to clinical symptoms in patients with idiopathic normal pressure hydrocephalus.

AIM: This study aimed to investigate the improvement in gait velocity variability after cerebrospinal fluid (CSF) elimination, and the association between gait velocity variability and gait and cognitive impairment in patients with idiopathic normal pressure hydrocephalus. METHODS: The gait velocity of 44 patients with idiopathic normal pressure hydrocephalus was measured using the Timed Up and Go Test (TUG) for a total of 10 times over 3 days each before and after CSF elimination. The coefficient of variation (CV) in the time required for the sequence of actions in TUG (TUG-CV) was calculated using 10 TUG data, and used for measuring intraindividual gait velocity variability. Gait quality was evaluated with the Gait Status Scale Revised (GSSR), and cognitive function was evaluated with the Mini-Mental State Examination and the Frontal Assessment Battery. RESULTS: The TUG, TUG-CV, GSSR and Frontal Assessment Battery results improved significantly after CSF elimination. The analyses using pre-CSF elimination results showed that the TUG-CV significantly and positively correlated with the TUG and GSSR results, and negatively with Mini-Mental State Examination results, but not with age and the Frontal Assessment Battery results. The stepwise multiple regression analysis indicates that the TUG, GSSR and Mini-Mental State Examination results were significant predictors of the TUG-CV. The analysis using data of change after CSF elimination showed that ΔTUG and ΔGSSR were significant predictors of ΔTUG-CV. CONCLUSIONS: Gait velocity variability improved after CSF elimination, and gait velocity variability was associated with gait disturbances and cognitive impairment in patients with idiopathic normal pressure hydrocephalus. Geriatr Gerontol Int 2024; 24: 693-699.

Effects of percutaneous cryoablation for renal tumor on overall and split renal function.

PURPOSE: To evaluate retrospectively the influence of percutaneous cryoablation for small renal tumors on total and affected kidney function and risk factors associated with worsening function of the affected kidney. MATERIALS AND METHODS: Between April 2016 and March 2022, 27 patients who underwent cryoablation for small renal tumors at our institution participated in this study, which investigated time-dependent changes in postoperative renal function. We evaluated estimated glomerular filtration rates (eGFRs) and split renal function revealed by scintigraphy using 99 m technetium-mercaptoacetyltriglycine (99mTc-MAG3) before cryoablation and at 1 week, 1 month, and 6 months after cryoablation. Numerous variables were analyzed to assess risk factors for worsening renal function. RESULTS: Baseline eGFR (mean ± standard deviation) was 56.5 ± 23.7 mL/min/1.73 m2 (mean ± SD; range, 20.5-112.5). Mean eGFRs at 1 week, 1 month, and 6 months after cryoablation were 57.4 ± 24.5 (19.1-114.9), 57.1 ± 25.1 (21.5-114.9), and 53.8 ± 23.9 mL/min/1.73 m2 (20.0-107.5), respectively. Changes were statistically insignificant (p = 1.0000, = 0.6749, and = 0.0761, respectively). Regarding split renal function, mean baseline contribution of the affected kidney determined by 99mTc-MAG3 was 49.7% ± 6.0% (38.8-63.3%); these rates at 1 week, 1 month, and 6 months after cryoablation were 43.7% ± 8.8 (29.1-70.6%), 46.2% ± 7.7% (32.6-70.3%), and 46.0% ± 8.5% (32.5-67.6%), respectively. Differences from baseline were significant for all periods (p < 0001, < 0001, = 0.0001, respectively). Serum C reactive protein and lactate dehydrogenase at 1 day following cryoablation, tumor's nearness to the collecting system or sinus, and volume of ablated normal renal parenchyma were significantly correlated with decreased contributions of the affected kidney by > 10% after cryoablation. CONCLUSION: Unlike total renal function, affected kidney function could worsen after cryoablation.

Three cases of recurrences after stent-graft placement for arterio-visceral/arterio-luminal fistulas in long-term follow-up.

We report 3 patients with recurrences after stent-graft placement for arterio-visceral/arterio-luminal fistulas in long-term follow-up. Two patients had ureteroarterial fistulas and the other had a tracheo-innominate artery fistula. All 3 patients had hemorrhage on initial presentation and underwent a stent-graft placement for an arterio-visceral/arterio-luminal fistula. Recurrences occurred over a period of 8-26 months and were diagnosed by contrast-enhanced computed tomography; pseudoaneurysms were found in contrast-enhanced computed tomography images in all cases. Pseudoaneurysms may be noted on contrast-enhanced computed tomography as the only finding of recurrences during long-term follow-up after stent-graft placement for arterio-visceral/arterio-luminal fistulas.

Quantitative analysis of liver standardized uptake value repeatability in SPECT/CT implications for clinical practice.

Purpose. The aim of this study was to assess the repeatability of the SUV normalized by liver volume (SUVL) between two liver receptor SPECT/CT studies performed on different days in patients with ICG-R15 values within normal range.Methods. 935 patients who underwent liver receptor scintigraphy between January 2010 and August 2018 were included. Patients who underwent liver resection, hepatic arterial embolization or had ICG-R15 >10% between scans were excluded, and 38 patients were finally included in the analysis. The repeatability of SUVL between scans was assessed using the intraclass correlation coefficient (ICC) (1.1) between SUVLmax, SUVLpeak and SUVLmean at the first and second scan and the additive and proportional errors from the Bland-Altman analysis.Results. In ICC (1,1), SUVLmax, SUVLpeak and SUVLmean were all greater than 0.8, indicating almost perfect repeatability; neither additive nor proportional errors were observed in the Bland-Altman analysis.Conclusions. In patients with ICG-R15 values within the normal range, the SUV Liver (SUVL) between two liver receptor SPECT/CT studies performed on different days was repeatability over time. It was suggested that the SUVL of liver receptor scintigraphy could be an indicator that could be used for follow-up over time in the assessment of liver fibrosis.

Analgesic efficacy and safety of percutaneous thermal ablation plus cementoplasty for painful bone metastases: a systematic review and meta-analysis.

PURPOSE: To conduct a systematic review and meta-analysis of publications to evaluate the analgesic efficacy and safety of percutaneous thermal ablation (PTA) plus percutaneous cementoplasty (PCP) (PTA + PCP) for painful bone metastases. METHODS: We searched PubMed, Cochrane Library and Embase for articles published up to October 2022. Outcomes were a 10-point pain scale, morphine equivalents daily dose (MEDD) and complications. A subgroup confined to spinal bone metastases was analyzed. RESULTS: Twenty-one articles were selected for the analysis. The 21 selected articles involved a total of 661 cases. The pooled pain scales at pre-PTA + PCP, 1 day, 1 week and 1-, 3-, and 6 months post-PTA + PCP were 7.60 (95% confidence interval [CI], 7.26-7.95, I2 = 89%), 3.30 (95% CI, 2.25-4.82, I2 = 98%), 2.58 (95% CI, 1.99-3.35, I2 = 94%), 2.02 (95% CI, 1.50-2.71, I2 = 93%), 1.78 (95% CI, 1.26-2.53, I2 = 95%), and 1.62 (95% CI, 1.14-2.31, I2 = 88%), and in the subgroup, 7.97 (95% CI, 7.45-8.52, I2 = 86%), 3.01 (95% CI, 1.43-6.33, I2 = 98%), 2.95 (95% CI, 1.93-4.51, I2 = 95%), 2.34 (95% CI, 1.82-3.01, I2 = 68%), 2.18 (95% CI, 1.57-3.03, I2 = 78%), and 2.01 (95% CI, 1.16-3.48, I2 = 86%). Mean MEDD decreased up to 3 months post-PTA + PCP in 4 articles. The overall pooled major complication rate was 4% (95% CI, 2-6%, I2 = 2%). CONCLUSIONS: The updated systematic review and meta-analysis indicates that PTA + PCP for painful bone metastases is safe, and can lead to rapid and sustained pain reduction.

Perioperative proximal splenic artery embolization in cirrhotic patients with splenomegaly.

INTRODUCTION: The purpose of this study was to determine the effect of proximal splenic artery embolization (SAE) in cirrhotic patients with splenomegaly who underwent surgical laparotomy. MATERIAL AND METHODS: This retrospective observational study included 8 cirrhotic patients with splenomegaly. They underwent proximal SAE before- (n = 6) or after (n = 2) laparotomy. Vascular plugs or coils were placed in the proximal splenic artery. The diameter of the portal vein and the splenic volume were recorded. Clinical outcome assessments included platelet counts, the model for end-stage liver disease (MELD) score, and complications. RESULTS: After embolization, the portal venous diameter was significantly smaller (pre: 13.6 ± 2.7 mm, post: 12.5 ± 2.3 mm, p = 0.023), the splenic volume was significantly decreased (pre: 463.2 ± 145.7 ml, post: 373.3 ± 108.5 ml, p = 0.008) and the platelet count was significantly higher (pre: 69.6 ± 30.8 × 103/µl, post: 86.8 ± 27.7 × 103/µl, p = 0.035). Before embolization, the median MELD score was 12; after embolization, it was 11 (p = 0.026). No patient developed post-treatment complications after embolization. CONCLUSIONS: The reduction of hypersplenism by perioperative proximal SAE may be safe and reduce the surgical risk in cirrhotic patients with splenomegaly.

Difference in arterial FDG accumulation in healthy study participants between digital PET/CT and standard PET/CT.

OBJECTIVE: To evaluate the differences in FDG accumulation in arteries throughout the body between digital and standard PET/CT. METHODS: Forty-six people who had FDG-PET examinations with a digital PET/CT scanner for health screening between April 2020 and March 2021 and had previous examinations with a standard PET/CT scanner were the study participants. FDG accumulation in arteries throughout the body was visually assessed in each segment. Scan was considered positive when arterial FDG accumulation was equal to or greater than that of the liver. The positivity rates for general arteries and each arterial segment were compared between the two kinds of scanners. If any one of the arterial segments was considered positive, the general arteries were classified as positive. Moreover, the rate of change in results from the standard PET/CT to the digital scanner in the same individual (negative to positive, positive to negative) was examined. RESULTS: In the evaluation of general arteries, the positivity rates were 21.7% (10 cases) for the standard PET/CT, whereas positive rates were 97.8% (45 cases) for the digital PET/CT (p < 0.001). In all arterial segments, the positivity rate was significantly higher with the digital PET/CT compared to the standard PET/CT; those with the digital PET/CT were, respectively, 95.7%, 87.0%, 73.9%, 37.0%, 34.8%, and 21.7% in the femoral, brachial, aortic, subclavian, iliac, and carotid arteries. On the other hand, those with the standard PET/CT were 13.0%, 13.0%, 19.6%, 2.2%, 0%, and 4.4% in segments in the above order. Changes from negative to positive were shown in many cases; 35 cases (76.0%) of general arteries, 38 cases (82.6%) for the femoral artery, and 34 cases (73.9%) for the brachial artery. The exception was one case in which a change from positive to negative was confirmed in the carotid artery. In all arteries considered to be positive, FDG accumulation was not greater than but was equal to that in the liver with both scanners. CONCLUSIONS: Arterial FDG accumulation was significantly higher with digital PET/CT compared to conventional PET/CT. With digital PET/CT, an arterial FDG accumulation equal to the liver may not to be considered as abnormal accumulation.

A Phase I Trial of Weekly Nab-paclitaxel Plus Carboplatin With Thoracic Radiotherapy for Non-small Cell Lung Cancer.

BACKGROUND/AIM: This study aimed to evaluate the safety and recommended dose of nab-paclitaxel in combination with carboplatin and thoracic radiotherapy for locally advanced non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Nab-paclitaxel was administered weekly with escalating doses, combined with carboplatin area under the curve (AUC) 2 and concurrent standard thoracic radiotherapy. Escalating doses of nab-paclitaxel were as follows: level 0, 30 mg/m2; level 1, 35 mg/m2; level 2, 40 mg/m2; level 3, 45 mg/m2 Results: Twelve patients were enrolled and received the treatment according to the protocol; seven patients (58%) had squamous cell carcinoma and all cases had stage III disease. At level 1, none of the three patients experienced dose limiting toxicity (DLT). At level 2, one of the first three patients experienced a fatal DLT of bronchopulmonary hemorrhage. None of the three more additional patients experienced DLT. At level 3, two of the three patients experienced a DLT of grade 3 febrile neutropenia and grade 4 neutropenia, respectively. Consolidation chemotherapy was provided to 10 of 12 patients. Radiation pneumonitis developed in five of 12 patients (42%). Eight patients (66.7%) showed partial response, and four (33.3%) showed stable disease. For the above reasons, level 2 (40 mg/m2) was considered the recommended dose in this study. CONCLUSION: Concurrent chemoradiotherapy with weekly nab-paclitaxel (40 mg/m2) and carboplatin (AUC 2) is a feasible and well-tolerated regimen in patients with previously untreated locally advanced NSCLC. A phase II trial with this regimen is warranted.

Spontaneous regression of small cell lung cancer associated with Lambert-Eaton Myasthenic Syndrome: Case report.

Spontaneous regression (SR) of cancer is very rare, especially of small cell lung cancer (SCLC). Recently, an association of paraneoplastic neurological syndrome (PNS) has been reported as a cause of SR of cancer, and onconeural antibodies are a possible factor in the SR of cancer associated with PNS. We herein report the first case of SR of SCLC combined with anti-P/Q-type of voltage-gated calcium channel (VGCC) antibody-positive Lambert-Eaton myasthenic syndrome (LEMS), a subtype of PNS. This case report suggests that SCLC may be spontaneously reduced by an autoimmune response induced by VGCC antibodies associated with LEMS. Our finding may help elucidate the mechanisms that inhibit tumor growth and cause the regression of tumors.

Guidelines for Central Venous Port Placement and Management (Abridged Translation of the Japanese Version).

The central venous port has been widely used for patients who require long-term intravenous treatments, and the number of palcement has been increasing. The Japanese Society of Interventional Radiology developed a guideline for central venous port placement and management to provide evidence-based recommendations to support healthcare providers in the decision-making process regarding the central venous port. The guideline consisted of two parts: (i) a comprehensive review of topics including preoperative preparation, techniques for placement or removal, complications, and maintenance methods and (ii) recommendations for the six clinical questions regarding blood vessels for central venous port placement, port implantation site, prophylactic antibiotic therapy, imaging guidance for puncture, disinfectant prior to accessing the central venous port, and the optimal procedure at the end of drug administration via the central venous port, generated on the basis of the rating quality of evidence by systematic review.

A case of pulmonary pleomorphic carcinoma associated with cystic airspace.

Lung cancer associated with a cystic airspace is frequently misdiagnosed or overlooked. Adenocarcinoma, followed by squamous cell carcinoma, is the most typical histologic type of lung cancer connected to a cystic airspace. Here we present the rare case of lung pleomorphic carcinoma associated with a cystic airspace. We encountered a 74-year-old Japanese man diagnosed by computed tomography (CT) as having a nodule outside a cystic airspace in the lung. Several previous CT images showed that the cystic airspace preceded the nodule. Postsurgery, pathology indicated a diagnosis of pleomorphic carcinoma. Since pulmonary pleomorphic carcinomas pursue an aggressive clinical course, their early detection may contribute to an improved prognosis. Our case demonstrated that pleomorphic carcinoma can arise with cystic airspaces. For early diagnosis of those aggressive lung cancers, chest physicians should carefully examine the walls of cystic airspaces on CT.

Percutaneous splanchnic nerve neurolysis analgesic efficacy and safety for cancer-related pain: a systematic review and meta-analysis.

PURPOSE: To perform a systematic review and meta-analysis of publications to evaluate the analgesic efficacy and safety of percutaneous splanchnic nerve neurolysis (SNN) for cancer-related pain. METHODS: We searched PubMed, Cochrane Library, and Ichushi-Web for English or Japanese articles published up to July 2022 and reporting patients who underwent percutaneous SNN for cancer-related pain. The outcome measures assessed in the systematic review and meta-analysis were the pain measurement scales and morphine equivalents daily dose (MEDD) before and after the intervention and the rate of complications. RESULTS: Pooled pain measurement scores at pre-intervention, 1-2 weeks, and at 1, 2, 3, and 6 months post-intervention were 6.65 (95% confidence interval [CI], 5.77-7.67, I2 = 97%), 2.79 (95% CI, 2.00-3.88, I2 = 88%), 2.82 (95% CI, 2.49-3.20, I2 = 55%), 2.86 (95% CI, 2.64-3.10, I2 = 0%), 2.99 (95% CI, 2.56-3.46, I2 = 82%), and 3.09 (95% CI, 1.44-6.65, I2 = 70%), respectively. Mean MEDD was described in 8 of the 11 included articles. In all 8 articles, MEDD decreased up to 3 months post-intervention. The pooled minor complication rates for diarrhea and hypotension were 28% (95% CI, 13-49%, I2 = 85%) and 31% (95% CI, 16-51%, I2 = 80%), respectively. The pooled major complication rate was 2% (95% CI, 1-2%, I2 = 0%). CONCLUSIONS: Analysis indicates that percutaneous SNN for cancer-related pain can be performed safely with sustained reduction of pain measurement scales while reducing the administration of opioids.

Stent-Graft Placement and Coil Embolization for Splenic Artery Aneurysm Derived from Isolated Spontaneous Celiac Artery Dissection.

We encountered a case of complex isolated spontaneous celiac artery dissection with a patent false lumen with both entry and re-entry and extensive aneurysmal degeneration of the splenic artery. The dissection entry was wide and was located at the origin of the celiac artery. The false lumen extended to the distal part of the splenic artery, obstructed the true lumen, and was connected to the true lumen at the splenic hilum via the re-entry. Treatment was successful by stent-graft placement for the occlusion of the entry and embolization of the re-entry with microcoils via the false lumen of the splenic artery.

Symptomatic Chronic Severe Stenosis of the Iliac Vein Successfully Treated Endovascularly Using an Interventional Radiology Computed Tomography System.

We report a woman with chronic severe stenosis of the left common and external iliac veins and severe post-thrombotic syndrome symptoms. We successfully recanalized the stenotic segment via interventional radiology, which immediately relieved the symptoms. The interventional radiology computed tomography system was helpful for the safe and precise performance of endovascular treatments.

Combining 99mTc-GSA single-photon emission-computed tomography and Gd-EOB-DTPA-enhanced magnetic resonance imaging for staging liver fibrosis.

Preoperative assessment of the degree of liver fibrosis is important to determine treatment strategies. In this study, galactosyl human serum albumin single-photon emission-computed tomography and ethoxybenzyl (EOB) contrast-enhanced magnetic resonance imaging (MRI) were used to assess the changes in hepatocyte function after liver fibrosis, and the standardized uptake value (SUV) was combined with gadolinium EOB-diethylenetriaminepentaacetic acid to evaluate its added value for liver fibrosis staging. A total of 484 patients diagnosed with hepatocellular carcinoma who underwent liver resection between January 2010 and August 2018 were included. Resected liver specimens were classified based on pathological findings into nonfibrotic and fibrotic groups (stratified according to the Ludwig scale). Galactosyl human serum albumin-single-photon emission-computed tomography and EOB contrast-enhanced MRI examinations were performed, and the mean SUVs (SUVmean) and contrast enhancement indices (CEIs) were obtained. The diagnostic value of the acquired SUV and CEIs for fibrosis was assessed by calculating the area under the receiver operating characteristic curve (AUC). In the receiver operating characteristic analysis, SUV + CEI showed the highest AUC in both fibrosis groups. In particular, in the comparison between fibrosis groups, SUV + CEI showed significantly higher AUCs than SUV and CEI alone in discriminating between fibrosis (F3 and 4) and no or mild fibrosis (F0 and 2) (AUC: 0.879, vs SUV [P = 0.008], vs. CEI [P = 0.023]), suggesting that the combination of SUV + CEI has greater diagnostic performance than the individual indices. Combining the SUV and CEI provides high accuracy for grading liver fibrosis, especially in differentiating between grades F0 and 2 and F3-4. SUV and gadolinium EOB-diethylenetriaminepentaacetic acid-enhanced MRI can be noninvasive diagnostic methods to guide the selection of clinical treatment options for patients with liver diseases.

Predicting the pathological invasiveness of early lung adenocarcinoma prior to surgery using Deauville criteria: reliability and validity.

PURPOSE: This retrospective study aimed to investigate the validity and reliability of FDG-PET/CT visual assessment using Deauville criteria to predict pathological invasiveness of early lung adenocarcinoma prior to surgery. MATERIALS AND METHODS: Between April 2020 and January 2022, 51 patients who underwent surgery for pathological stage 0/I lung adenocarcinoma were enrolled. The pulmonary lesions were divided into two groups according to pathological invasiveness: less invasive (including adenocarcinoma in situ and minimally invasive adenocarcinoma and invasive adenocarcinoma. We compared CT size (total and solid size), SUVmax, and Deauville score between the two groups. Furthermore, we investigated inter-rater and intra-rater agreements regarding the Deauville score. Receiver operating characteristic (ROC) curve analysis was performed to identify the diagnostic performance of each method. RESULTS: Based on pathologic diagnoses, 51 lesions in the 51 patients were divided into 6 less invasive and 45 invasive adenocarcinoma lesions. According to quadratic-weighted Kappa statistics, inter-rater (k = 0.93) and intra-rater (k = 0.97) agreements among all five components of the Deauville score indicated high agreement. There was a statistically significant difference in CT solid size, SUVmax, and Deauville score between the two groups. There were no significant differences between CT solid size and FDG-PET/CT assessments (AUC = 0.93 for Deauville score and SUVmax, AUC = 0.84 for CT solid size). CONCLUSION: FDG-PET/CT visual assessment using the Deauville score could assist in deciding upon minimally invasive surgery for early lung adenocarcinoma.

Removal of central venous port-catheter by the combination of interventional radiological procedures.

We encountered a patient with an infection related to an implanted central venous port-catheter that necessitated removal of the system. As the catheter had tightly adhered to the venous wall, removal was impossible with standard methods. After trial and error, we used a guiding catheter that was advanced over the implanted catheter to detach the fibrin sheath on the implanted catheter that had adhered to the vessel wall. At that time, a pull-through technique was used. After we succeeded in detaching the adhesion with the guiding catheter, we were able to withdraw the implanted catheter.

Perceptual and objective physical quality of chest images: a comparison between digital radiographic chest images processed for cancer screening and pneumoconiosis screening in Japan.

This study (1) evaluated the perceptual and objective physical quality of digital radiographic chest images processed for different purposes (routine hospital use, lung cancer screening, and pneumoconiosis screening), and (2) quantified objectively the quality of chest images visually graded by the Japan National Federation of Industrial Health Organization (ZENEIREN). Four observers rated the images using a visual grading score (VGS) according to ZENEIREN's quality criteria. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured. Between groups, differences were assessed using ANOVA (followed by Bonferroni multiple comparisons) or unpaired t-test. The Pearson's correlation coefficients were calculated for the correlation between perceptual quality and objective physical image quality. The image quality perceived by the observers and the SNR measurements were highest for the images generated using parameters recommended for lung cancer screening. The images processed for pneumoconiosis screening were rated poorest by the observers and showed the lowest objective physical quality measurements. The chest images rated high quality by ZENEIREN generally showed a higher objective physical image quality. The SNR correlated well with VGS, but CNR did not. Highly significant differences between the processing parameters indicate that image processing strongly influences the perceptual quality of digital radiographic chest images.

Percutaneous Transhepatic Obliteration for Treating Stomal Variceal Bleeding Using a Microballoon Catheter with Systemic Drainage Vein Compression.

We report a case of successful treatment of stomal variceal bleeding with percutaneous transhepatic obliteration using a microballoon catheter concomitantly with drainage vein compression. A 72-year-old man with alcoholic cirrhosis was admitted to our hospital due to repeated hemorrhage of stomal varices. Percutaneous transhepatic obliteration was then selected for treatment because computed tomography revealed the stomal varices being fed by only two branches of the superior and inferior mesenteric veins. During microballoon inflation, 5% ethanolamine oleate with iopamidol was injected into each branch, and the systemic drainage veins were compressed by the gauze from the body surface near the stoma. No rebleeding from the stomal varices has been observed 14 months after the procedure.

Association of right precuneus compression with apathy in idiopathic normal pressure hydrocephalus: a pilot study.

Apathy is frequently observed in idiopathic normal pressure hydrocephalus (iNPH) and worsens cognitive impairment and gait disturbance. In this study, we evaluated the regions associated with apathy in iNPH using statistical imaging analysis on the whole brain, both in terms of cerebral blood flow and gray matter volume. Twenty-seven patients with iNPH were assigned to two groups based on their scores on the neuropsychiatric inventory items related to apathy; 18 patients were assigned to the group with apathy (iNPH + APA) and 9 to the group without apathy (iNPH - APA). The magnetic resonance images and cerebral blood flow single-photon emission computed tomography data of the two groups were compared using statistical parametric mapping 12. The regional gray matter volume of the right precuneus was significantly larger in the iNPH + APA group than in the iNPH - APA group, but the regional cerebral blood flow in any region of the brain was not significantly different between the two groups. These results suggested that the larger gray matter volume, which is thought to reflect gray matter compression, in the precuneus might be involved in apathy in iNPH.