Does the Age of Donor Kidneys Affect Nocturnal Polyuria in Patients With Successful Real Transplantation?

BACKGROUND

We investigated whether the age of donor kidneys influences the incidence of nocturnal polyuria in patients with successful renal transplantation (RTX).

METHODS

Eighty-five patients (45 men and 40 women) undergoing RTX (median age, 47 years) were included in this study. Twenty-four-hour bladder diaries were kept for 3 days, and nocturnal polyuria was defined as a nocturnal polyuria index (nocturnal urine volume/24-hour urine volume) of >0.33. Risk factors for nocturnal polyuria were analyzed in patients with RTX by means of the Mann-Whitney U test, χ² test, and a logistic regression analysis.

RESULTS

End-stage renal disease (ESRD) developed from diabetes mellitus in 16 patients (19%). Sixty-five patients (76%) received pre-transplant dialysis, with a median duration of 5 years. The median serum creatinine level and body mass index at the most recent visit were 1.2 mg/dL and 21.2 kg/m², respectively. On the basis of the 24-hour bladder diaries, nocturnal polyuria was identified in 48 patients (56%). A logistic regression analysis revealed that diabetes mellitus as the original disease for ESRD was the only risk factor for nocturnal polyuria (odds ratio, 8.95; 95% confidence interval, 2.01-65.3; P = .0028). The age of donor kidneys at examination did not affect the incidence of nocturnal polyuria (P = .9402).

CONCLUSIONS

Nocturnal polyuria was not uncommon in patients with successful RTX. Diabetes mellitus as the original disease for ESRD was the only risk factor for nocturnal polyuria, whereas the age of donor kidneys at examination did not affect the incidence of nocturnal polyuria. Thus, nocturnal polyuria is caused by recipient factors but not donor factors.

Predictive factor for intraoperative tumor rupture of Wilms tumor

PURPOSE

For Wilms tumor, intraoperative tumor rupture with wide tumor spillage during surgical manipulation raises the classification to stage 3. Then, postoperative chemotherapy must be more intensive, and abdominal radiotherapy is added. Therefore, intraoperative tumor rupture should be avoided if possible. However, predictive factors for intraoperative tumor rupture have not been sufficiently described. Here we examined the risk factors for intraoperative tumor rupture.

METHODS

Patients with Wilms tumor who underwent treatment according to the National Wilms Tumor Study or the Japanese Wilms Tumor Study protocol at our institution were reviewed retrospectively. Collected cases were categorized into two groups: the ruptured group and the non-ruptured group. Risk factors for intraoperative tumor rupture, including the ratio of the tumor area to the abdominal area in a preoperative single horizontal computed tomography slice (T/A ratio), were investigated in both groups.

RESULTS

The two groups were not different in age, body weight, tumor laterality, sex, or histological distribution. The T/A ratio in the ruptured group was significantly higher than that in the non-ruptured group. Receiver operating characteristic curve analysis identified a discriminative value for a T/A ratio >0.5.

CONCLUSION

The T/A ratio can be a predictive factor for intraoperative tumor rupture of Wilms tumor.

Surgical intervention strategies for congenital tracheal stenosis associated with a tracheal bronchus based on the location of stenosis

PURPOSE

The aim of this study was to determine the appropriate surgical intervention strategies for congenital tracheal stenosis (CTS) associated with a tracheal bronchus based on the location of stenosis.

METHODS

The medical records of 13 pediatric patients with CTS associated with a tracheal bronchus at a single institution between January 2006 and December 2015 were retrospectively reviewed.

RESULTS

Type 1: tracheal stenosis above the right upper lobe bronchus (RULB) (n = 1). One patient underwent slide tracheoplasty and was successfully extubated. Type 2: tracheal stenosis below the RULB (n = 7). Tracheal end-to-end anastomosis was performed before 2014, and one patient failed to extubate. Posterior-anterior slide tracheoplasty was performed since 2014, and all three patients were successfully extubated. Type 3: tracheal stenosis above the RULB to the carina (n = 5). One patient underwent posterior-anterior slide tracheoplasty and was successfully extubated. Two patients with left-right slide tracheoplasty and another two patients with tracheal end-to-end anastomosis for the stenosis below the RULB could not be extubated.

CONCLUSION

Tracheal end-to-end anastomosis or slide tracheoplasty can be selected for tracheal stenosis above the RULB according to the length of stenosis. Posterior-anterior slide tracheoplasty appears feasible for tracheal stenosis below the RULB or above the RULB to the carina.

Keratin 17 Is Induced in Oral Cancer and Facilitates Tumor Growth

Keratin subtypes are selectively expressed depending on the cell type. They not only provide structural support, but regulate the metabolic processes and signaling pathways that control the growth of the epithelium. KRT17 (keratin 17) is induced in the regenerative epithelium and acts on diverse signaling pathways. Here, we demonstrate that KRT17 is invariably and permanently induced in oral squamous cell carcinoma (OSCC), as revealed by immunohistochemistry and cDNA microarray analysis. Two representative OSCC cell lines; KRT17-weakly expressing Ca9-22 and KRT17-highly expressing HSC3 were used to establish KRT17-overexpressing Ca9-22 and KRT17-knockdown HSC3 cells. Analysis of these cells revealed that KRT17 promoted cell proliferation and migration by stimulating the Akt/mTOR pathway. KRT17 also upregulated the expression of SLC2A1 (solute carrier family 2 member 1/Glut1) and glucose uptake. To further investigate the effect of KRT17 on tumorigenesis, KRT17-knockout HSC3 cells were established and were transplanted to the cephalic skin of nude mice. The tumors that developed from KRT17-knockout HSC3 cells had a lower Ki-67 labeling index and were significantly smaller compared to the controls. These results indicate that KRT17 stimulates the Akt/mTOR pathway and glucose uptake, thereby facilitating tumor growth. We could not confirm the relationship between KRT17 and SFN (stratifin) in the cells examined in this study. However, our study reinforces the concept that the cellular properties of cancer are regulated by a series of molecules similar to those found in wound healing. In OSCC, KRT17 acts as a pathogenic keratin that facilitates tumor growth through the stimulation of multiple signaling pathways, highlighting the importance of KRT17 as a multifunctional promoter of tumorigenesis.

Impact of a β-blocker and/or acute hemodilution on cerebral oxygenation during apneic hypoxia

BACKGROUND

β-blockers reduce the tolerance for acute hemodilution by decreasing cerebral oxygenation and may contribute to the incidence of stroke. We hypothesized that β-blockers also increase the risk for cerebral hypoxia when apneic hypoxia occurs.

METHODS

After induction of isoflurane, 14 swine (mean ± SD =25.3 ± 0.8 kg) were studied using 200 μg/kg/min of landiolol or saline (control group) in three sequential stages: before, during, and after landiolol (saline) infusion. In each stage, after 5 min of mechanical ventilation with 100% oxygen, apnea was induced until the time to < 70% oxygen saturation. Hemodynamic and blood gas variables were measured, and the cerebral tissue oxygenation index (TOI) was recorded by near infrared spectroscopy (apnea experiment). After these steps, hemodilution was induced by hemorrhage of 600 ml and infusion of the same volume of hydroxyethylstarch, and the apnea experiments were then conducted before, during, and after landiolol (saline) infusion similarly to before hemodilution.

RESULTS

Landiolol decreased TOI at 1 min after apnea and at SpO2 < 70% by 3.3% and 7.0% from each corresponding value at baseline, and by 13.1% and 20.3% during hemodilution. Landiolol shifted the relationship between TOI and arterial hemoglobin oxygen saturation (SaO2 ) or arterial partial pressure of oxygen (PaO2 ) to the left; and reduced TOI at similar arterial blood oxygenation. This phenomenon was marked during hemodilution.

CONCLUSIONS

Landiolol reduces cerebral tissue oxygenation during apneic hypoxia. β-blockers increase the risk for cerebral hypoxia when apneic hypoxia occurs, especially during acute hemodilution.

Density and temperature characterization of long-scale length, near-critical density controlled plasma produced from ultra-low density plastic foam

The ability to produce long-scale length (i.e. millimeter scale-length), homogeneous plasmas is of interest in studying a wide range of fundamental plasma processes. We present here a validated experimental platform to create and diagnose uniform plasmas with a density close or above the critical density. The target consists of a polyimide tube filled with an ultra low-density plastic foam where it was heated by x-rays, produced by a long pulse laser irradiating a copper foil placed at one end of the tube. The density and temperature of the ionized foam was retrieved by using x-ray radiography and proton radiography was used to verify the uniformity of the plasma. Plasma temperatures of 5-10 eV and densities around 10(21) cm(-3) are measured. This well-characterized platform of uniform density and temperature plasma is of interest for experiments using large-scale laser platforms conducting High Energy Density Physics investigations.

A Case of Juxtaglomerular Cell Tumor, or Reninoma, of the Kidney Treated by Retroperitoneoscopy-Assisted Nephron-Sparing Partial Nephrectomy Through a Small Pararectal Incision

A 15-year-old girl was found to be hypertensive (230-270/140-170 mm Hg) without any subjective symptoms. Magnetic resonance imaging confirmed the presence of a well-defined 22 mm hypodense lesion in the lower pole of the left kidney, located close to the renal hilum. Plasma rennin activity was elevated (75 ng/mL/h), and reninoma was diagnosed. Retroperitoneoscopy-assisted nephron-sparing surgery was planned. The retroperitoneum was accessed through a 4 cm left pararectal upper abdominal incision. Following blunt dissection, the abdominal wall was elevated with a lifting bar and lifting retractor, inserted below the 12th rib in the anterior axillary line to create sufficient working space in the retroperitoneal cavity without the need for pneumoperitoneum. Three 5 mm trocars were introduced above the superior iliac crest for the camera and the assistant. Gerota's fascia was opened and the kidney exposed. The surgeon dissected the left kidney through the minilaparotomy incision under both direct vision and using the magnified view on the monitor, which was particularly effective for the lateral and posterior sides of the kidney. The posterior peritoneum was incised intentionally next to the diaphragm to allow further mobilization of the kidney. Diathermy was used to remove the tumor and a layer of surrounding normal parenchymal tissue at least 0.5 cm thick. The histopathologic diagnosis was reninoma. Ischemia time was 14 minutes. Postoperatively, both plasma rennin activity and blood pressure were normal (1.9 ng/mL/h and 90-110/70-80 mm Hg, respectively). After follow-up of 12 months, there is no evidence of recurrence.

Laparoscopic Heller Myotomy for Non-Dilated Esophageal Achalasia in Children with Intraoperative Stepped Dilation Under Image Guidance: Attempting Complete Myotomy

This study presents a modified surgical approach to laparoscopic myotomy for achalasia using stepped dilation with a Rigiflex balloon and contrast medium under image guidance. A 10-year-old boy with persistent dysphagia and vomiting had ingested only liquids for 3 months, losing >10 kg in body weight. Barium swallow and esophageal manometry diagnosed esophageal achalasia with mild esophageal dilatation. After failed pneumatic dilatation, laparoscopic Heller myotomy with Dor fundoplication was performed. Prior to surgery, a Rigiflex balloon dilator was placed within the esophagus near the diaphragmatic hiatus. A four-port technique was used, and mobilization of the esophagus was limited to the anterior aspect. A 5-cm Heller myotomy was performed, extending another 2 cm onto the anterior gastric wall. During myotomy, the Rigiflex balloon was serially dilated from 30 to 50 mL, and filled with contrast medium under fluoroscopic image guidance in order to maintain appropriate tension on the esophagus to facilitate myotomy, and to confirm adequate myotomy with sufficient release of lower esophageal sphincter by resecting residual circular muscle fibers. Residual circular muscle fibers can be simultaneously visualized under both fluoroscopic image guidance and direct observation through the laparoscope, and they were cut precisely until the residual notch fully disappeared. Dor fundoplication was completed. The operative time was 180 minutes, and oral intake was started after esophagography on postoperative day 1. As of the 12-month follow-up, the patient has not shown any symptoms, and his postoperative course appeared satisfactory.

Temporal variability of glucocorticoid receptor activity is functionally important for the therapeutic action of fluoxetine in the hippocampus

Previous studies have shown inconsistent results regarding the actions of antidepressants on glucocorticoid receptor (GR) signalling. To resolve these inconsistencies, we used a lentiviral-based reporter system to directly monitor rat hippocampal GR activity during stress adaptation. Temporal GR activation was induced significantly by acute stress, as demonstrated by an increase in the intra-individual variability of the acute stress group compared with the variability of the non-stress group. However, the increased intra-individual variability was dampened by exposure to chronic stress, which was partly restored by fluoxetine treatment without affecting glucocorticoid secretion. Immobility in the forced-swim test was negatively correlated with the intra-individual variability, but was not correlated with the quantitative GR activity during fluoxetine therapy; this highlights the temporal variability in the neurobiological links between GR signalling and the therapeutic action of fluoxetine. Furthermore, we demonstrated sequential phosphorylation between GR (S224) and (S232) following fluoxetine treatment, showing a molecular basis for hormone-independent nuclear translocation and transcriptional enhancement. Collectively, these results suggest a neurobiological mechanism by which fluoxetine treatment confers resilience to the chronic stress-mediated attenuation of hypothalamic-pituitary-adrenal axis activity.

Japanese encephalitis

Japanese encephalitis (JE) is an inflammation of the central nervous system in humans and animals, specifically horses and cattle. The disease, which can sometimes be fatal, is caused by the flavivirus Japanese encephalitis virus (JEV), of which there are five genotypes (genotypes 1, 2, 3, 4 and 5). The transmission cycle of the virus involves pigs and wild birds as virus amplifiers and mosquitoes as vectors for transferring the virus between amplifying hosts and to dead- end hosts, i.e. humans, horses and cattle. In horses and cattle the disease is usually asymptomatic, but when clinical signs do occur they include fever, decreased appetite, frothing at the mouth, rigidity of the legs and recumbency, and neurological signs, such as convulsive fits, circling, marked depression and disordered consciousness. In pigs, it can cause abortion and stillbirths. At present, the virus is detected in a wide area covering eastern and southern Asia, Indonesia, northern Australia, Papua New Guinea and Pakistan. JEV RNA has also been detected in Italy, first in dead birds in 1997 and 2000 and then in mosquitoes in 2010. Genotype shift, i.e. a change of genotype from genotype 3 to genotype 1, has occurred in some countries, namely Japan, South Korea, Chinese Taipei and Vietnam. Laboratory methods are available for confirming the causative agent of the disease. There are control measures to prevent or minimise infection and, among them, vaccination is one of the most important and one which should be adopted in endemic and epidemic areas.

Brain abscess in hepatopulmonary syndrome associated with biliary atresia

The first-choice therapy for biliary atresia (BA) is Kasai hepatoportoenterostomy, which has been shown to greatly improve outcome. Various long-term complications, however, such as portal hypertension and hepatopulmonary syndrome (HPS), can occur in patients with native liver. A rare case of brain abscess in an 11-year-old girl with HPS associated with BA is reported. The patient underwent hepatoportoenterostomy for BA at 53 days of age, with resolution of hyperbilirubinemia. At 10 years of age, she was diagnosed with severe HPS with right-to-left shunting, and preparations for liver transplantation proceeded. Three months after the diagnosis, she had a right parietal brain abscess. Given that the brain abscess enlarged in size, surgical drainage of the brain abscess was performed. The postoperative course was uneventful, but a slight left hemiplegia remained at discharge. The presumed mechanism of abscess formation in HPS may be right-to-left bacterial transit through intrapulmonary vascular dilatations and/or arteriovenous fistulae.

Temperature seasonality during fry out-migration influences the survival of hatchery-reared chum salmon Oncorhynchus keta

Among years, fry-to-adult survival of hatchery-reared chum salmon Oncorhynchus keta was positively correlated with the length (in days) of the fry out-migration period with temperatures suitable for migration. Furthermore, survival decreased with increasing difference in mean temperature between May and June. Thus, prolonged out-migration periods increased the probability of survival from fry to adult, lending support to the hypothesis that long migration periods decrease the risk of mortality (bet-hedging), and increase the probability of migration when environmental conditions in fresh water and the ocean are suitable (match-mismatch).

Laparoscopic Toupet fundoplication for gastroesophageal reflux: a series of 131 neurologically impaired pediatric cases at a single children's hospital

PURPOSE

To present the medium to long-term outcome of the largest pediatric series of laparoscopic Toupet fundoplications (LTF) performed at a single institution.

PATIENTS AND METHODS

Subjects were 131 neurologically impaired children (81 M, 50 F) who underwent LTF between 2003 and 2013. Our LTF involves full dissection of the crus of the diaphragm to allow the intraabdominal esophagus to be mobilized at least 3-4 cm.

RESULTS

Preoperative mean fraction time for pH <4 was 14.6 %. Mean age at LTF was 6.7 years (3 months-18 years). Mean duration of follow-up was 5.7 years (range 1.2-12.1 years). One case required conversion to open surgery. Intra-operative complications were all injuries to the esophagus/gastric wall (n = 4; 3.0 %) including full-thickness perforation (n = 1; 0.8 %). Postoperative complications included pyloric stenosis (n = 4; 3.0 %), dysphagia (n = 1; 0.8 %), incisional hernia (n = 1; 0.8 %), hemorrhage requiring transfusion (n = 1; 0.8 %), recurrence (n = 3; 2.3 % at 11, 13, and 48 months, respectively), and gastrostomy site infection (n = 7; 5.3 %). Mean operative time decreased significantly with experience from 180.8 min for the first quarter of subjects to 150.6 (2nd quarter), 128.6 (3rd) and 109.2 min (4th).

CONCLUSIONS

Our LTF would appear to be safe for treating GERD in children because of reliable outcome and low recurrence.

Severe acquired subglottic stenosis in children: analysis of clinical features and surgical outcomes based on the range of stenosis

PURPOSE

The present study analyzed the clinical features and surgical outcomes of laryngotracheal reconstruction (LTR) in pediatric patients with severe acquired subglottic stenosis (SGS) based on the range of stenosis. The aim was to clarify the indications for LTR in severe acquired SGS.

METHODS

The medical records of 33 pediatric patients with severe acquired SGS (Myer-Cotton grade III or IV) at our institution between January 1994 and December 2013 were retrospectively reviewed.

RESULTS

Nine patients had stenosis localized at the subglottis (localized SGS), and twenty-four patients had stenosis extending to the glottis or supraglottis from the subglottis (extended SGS). 66.7 % (6/9) of localized SGS patients were intubated after infancy, and 95.8 % (22/23) of extended SGS patients were intubated in the neonatal period. The duration of intubation was significantly shorter with localized than with extended SGS. Sixteen patients underwent LTR. The operation-specific decannulation rate was 80.0 % (4/5) in the localized SGS group and 14.3 % (1/7) in the extended SGS group.

CONCLUSION

The range of stenosis was affected by the period and duration of endotracheal intubation. Surgical outcomes of LTR tended to differ between localized SGS and extended SGS. LTR can be effective for localized SGS.

Laparoscopic Toupet Fundoplication using an Air Seal Intelligent Flow System and Anchor Port in a 1.8-kg infant: A Technical Report

INTRODUCTION

We report a case of a 1.8-kg infant who had laparoscopic Toupet fundoplication (LTF) using the AirSeal Intelligent Flow System and Anchor Port (AP).

MATERIALS AND SURGICAL TECHNIQUE

Our case had severe gastroesophageal reflux in association with genetic and cardiac anomalies. Despite the patient being continuously fed, persistent vomiting caused failure to thrive, and LTF was performed at 4 months of age when he weighed 1.8 kg. The AirSeal Intelligent Flow System is a novel laparoscopic CO2 insufflation system that improves the visual field by constantly evacuating smoke and providing a more stable pneumoperitoneum. The AP is a recently developed, stretchable, elastomeric, low-profile cannula. Three 5-mm AP were inserted: one subumbilically for the scope and one in both the right and left upper abdomen for the surgeon. A 5-mm AirSeal trocar was inserted in the left lower abdomen for the assistant. The gastrosplenic ligament was dissected free, and the intra-abdominal esophagus was prepared. A posterior hiatoplasty was performed, followed by the 270° fundoplication. During the fundoplication, the esophagus was fixed to the crus and then the right and left wraps were fixed to the esophagus. Pneumoperitoneum was maintained stably throughout the LTF procedure, with optimal operative field. Total operating time for LTF was 90 min. Body temperature dropped from 37.4°C to 35.7°C during pneumoperitoneum but resolved once pneumoperitoneum was ceased. Postoperative progress was uneventful, and an upper gastrointestinal study on postoperative day 2 showed no residual gastroesophageal reflux.

DISCUSSION

We believe the AirSeal Intelligent Flow System and AP contributed to the successful completion of LTF in a 1.8-kg infant.

Laparoscopic suture repair of idiopathic gastric perforation in Duchenne muscular dystrophy

We report herein an adolescent case of Duchenne muscular dystrophy (DMD) with idiopathic gastric perforation, in which emergency surgical repair was performed laparoscopically. A 14-year-old nonambulatory boy with DMD was brought to our emergency department with sudden onset of severe abdominal pain and distention. Plain radiograph and computed tomography confirmed the presence of free intraperitoneal air and intrapelvic effusion. The patient elected to undergo laparoscopic inspection with 4 trocars, revealing a focal perforation, 3-4 cm in diameter, on the upper gastric body near the diaphragm. The stomach was also found to have a thin wall without evidence of peptic ulcer disease or other abnormalities. An interrupted suture was placed using 4-0 PDS. The abdomen was extensively irrigated, and multiple J-Vac drains were left in situ. Total operation time was 90 min, and no intraoperative complications were encountered. Enteral feeding through a nasogastric tube was started on postoperative day 7. The postoperative course has been uneventful as of the 12-month follow-up. Pediatric surgeons should be aware of the increased risk of gastric perforation associated with DMD, and that laparoscopic repair can be safely performed even in emergency settings.

Gastric adenocarcinoma of fundic gland type (chief cell predominant type) with unique endoscopic appearance curatively treated by endoscopic submucosal resection

Gastric adenocarcinoma of fundic gland type [chief cell predominant type; (GA-FD-CCP)] is a rare gastric cancer variant arising from non-atrophic mucosa without Helicobacter pylori infection in the upper third portion of the stomach. GA-FD-CCP originates deep in the mucosal layer; hence, endoscopic lesion detection is often difficult at an early stage because of a minimal change in the mucosal surface. Here we present a 66-year-old man with an early stage of GA-FD-CCP showing characteristic endoscopic features. Esophagogastroduodenoscopy demonstrated a flat, slightly reddish area with black pigment dispersion and irregular micro-surface structure at the gastric fornix. The tumor was resected by endoscopic submucosal dissection and was pathologically diagnosed as GA-FD-CCP. Prussian blue staining revealed that the black pigment was a hemosiderin deposition. We reported a rare case of successfully treated GA-FD-CCP with black pigmentation that aided in early lesion detection.

Visualization of the Medial and Lateral Geniculate Nucleus on Phase Difference Enhanced Imaging

BACKGROUND AND PURPOSE

The precise identification and measurement of the medial geniculate nucleus and lateral geniculate nucleus on MR imaging remain technically challenging because the thalamic nuclei are small structures. We compared the visualization of the medial geniculate nucleus and lateral geniculate nucleus on phase difference enhanced imaging with 3D high-resolution phase imaging, 2D-T2WI, STIR, proton attenuation-weighted imaging, and DTI acquired at 3T. We also measured the volume and height of the medial geniculate nucleus and lateral geniculate nucleus on phase difference enhanced imaging.

MATERIALS AND METHODS

Phase difference enhanced, 2D-T2-weighted, STIR, proton attenuation-weighted, and DTI were acquired on a 3T MR imaging unit in 10 healthy volunteers. Two neuroradiologists recorded the qualitative visualization scores of the medial geniculate nucleus and lateral geniculate nucleus, specifically the identification of their boundaries, for all images. Measurement differences were assessed with the Wilcoxon signed rank test. The volume and height of the medial geniculate nucleus and lateral geniculate nucleus were measured on phase difference enhanced imaging and compared with previously reported values.

RESULTS

The qualitative visualization scores of the lateral geniculate nucleus and medial geniculate nucleus were significantly higher on phase difference enhanced images than on T2-weighted, proton attenuation-weighted, STIR, or DTI (P < .05). On phase difference enhanced imaging, the medial geniculate nucleus and lateral geniculate nucleus were bordered by low-intensity structures: the cerebral peduncle, the origin of the optic radiation, and the superior and inferior quadrigeminal brachia. The volume of the medial geniculate nucleus and lateral geniculate nucleus varied from 74.0 to 183.75 mm(3) (mean, 129.0 ± 34.7 mm(3)) and from 96.5 to 173.75 mm(3) (mean, 135.2 ± 28.0 mm(3)), respectively.

CONCLUSIONS

For the depiction of the medial geniculate nucleus and lateral geniculate nucleus on 3T MR imaging, phase difference enhanced imaging is superior to conventional MR imaging. The medial geniculate nucleus and lateral geniculate nucleus volumes vary among individuals.