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Although androgen therapy resistance and poor clinical outcomes are seen in most canine prostate cancer cases, there are only a few tools for analysing canine prostate cancer by using a cell biological approach. Therefore, to evaluate androgen-independent neoplastic cell growth, a new canine prostate cancer cell line ( CHP-1) was established in this study. CHP-1 over-expressed the co-chaperone small glutamine-rich tetratricopeptide repeat-containing protein α ( SGTA), which is over-expressed in human androgen-independent prostate cancer. The CHP-1 xenograft also showed SGTA over-expression. Although CHP-1 shows poor androgen receptor ( AR) signalling upon dihydrotestosterone stimulation, forced expression of AR enabled evaluation of AR signalling. Taken together, these results suggest that CHP-1 will be a useful model for investigating the pathogenesis of androgen-dependent and androgen-independent canine prostate cancer. [ABSTRACT FROM AUTHOR]

The present work investigates the multigenerational effects of paternal pre-conceptional exposure to continuous low-dose-rate gamma rays in C56BL/6J mice. Male C57BL/6J (F0 sires) mice were exposed to low dose rates of 20, 1, and 0.05 mGy/day for 400 days, to total accumulated doses of 8,000, 400, and 20 mGy, respectively. Upon completion of the radiation exposure, the F0 male mice were immediately bred to non-irradiated 8-week-old C57BL/6J females (F0 dams) to produce the first-generation (F1) mice. Randomly selected F1 males and females were then bred to produce the second-generation (F2) mice. All the mice, except the F0 dams, were subjected to pathological examination upon natural death. Reproductive parameters, lifespan, causes of death, neoplasm incidences and non-neoplastic disease incidences were used as parameters to evaluate the biological effects of continuous pre-conceptional exposure of the sires (F0) to continuous low-dose-rate radiation. There were no significant differences in the pregnancy and weaning rates among the parent (F0) generation. Average litter size and average number of weaned pups (F1) from dams bred to males (F0) exposed to 20 mGy/day were significantly decreased compared to the non-irradiated controls. Significant lifespan shortening in the sires (F0) was observed only in the 20 mGy/day group due to early death from malignant lymphomas. Life shortening was also observed in the F1 progeny of sires (F0) exposed to 20 and 1 mGy/day, but could not be attributed to a specific cause. No significant differences in the causes of death were found between dose groups in any generation. The number of primary tumors per mouse was significantly increased only in the F0 males exposed to 20 mGy/day. Except for the increased incidence rate for Harderian gland neoplasms in sires (F0) exposed to 20 mGy/day, there was no significant difference in neoplasm incidences and tumor spectra in all 3 generations in each sex regardless of radiation exposure. No multi- or transgenerational effects in the parameters examined were observed in the F1 and F2 progeny of sires exposed to 0.05 mGy/day for 400 days., (© 2024 by Radiation Research Society. All rights of reproduction in any form reserved.)

Institute for Radiological Science (NIRS), National Institutes for Quantum Science and Technology (QST), and Institute for Environmental Sciences (IES) have conducted large-scale animal experiments for radiation risk analyses in terms of life shortening and cancer prevalence. It is important to store data and biological samples from these large-scale experiments for sharing and future use since the economic and practical limitations, as well as the ethical considerations, make it difficult. QST/NIRS established an archive called the Japan Storehouse of Animal Radiobiology Experiments (J-SHARE) for the purpose of storing and sharing these historic collections. We plan to integrate the data and tissue specimen images obtained at the IES into J-SHARE by standardizing the archive format, with the aim of maximizing the results of radiation biology research. This integration is expected to contribute to the generation of new knowledge for radiation risk assessment and the provision of scientifically based information on radiation protection., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Mammary adenocarcinoma, the most common cancer in female dogs, often exhibits the lymph node and lung metastases and has a higher mortality rate. However, mammary adenocarcinoma has no established treatment, except early surgical excision. Canine mammary carcinoma has many common features with human mammary carcinoma, including clinical characteristics, heterogeneity, and genetic aberrations, making it an excellent spontaneous tumor model for human breast cancer. Diverse cancers comprised heterogeneous cell populations originating from cancer stem cells (CSCs) with self-renewal ability. Therefore, in addition to conventional therapy, therapeutic strategies targeting CSCs are essential for cancer eradication. The present study aimed to extract inhibitors of canine mammary CSCs that suppress their self-renewal ability. Sphere-formation assay, which evaluates self-renewal ability, was performed for the canine mammary cancer cell lines CTBp and CNMp. The spheres formed in this assay were used in inhibitor library screening, which identified various signaling pathways such as proteosome, stress inducer, and mammalian target of rapamycin (mTOR). The present study focused on the mTOR signaling pathway. Western blotting showed higher levels of phosphorylated mTOR in sphere-forming CTBp and CNMp cells than in adherent cells. Drug sensitivity examination using the mTOR inhibitors everolimus and temsirolimus revealed dose-dependent reductions in viability among both sphere-forming cells and adherent cells. Expression of phosphorylated mTOR in adherent and sphere-forming cells decreased by everolimus and temsirolimus treatment. In mice transplanted with CTBp-derived spheres, everolimus treatment significantly decreased tumor volume compared to control. These results reveal that the mTOR signaling pathway may be a potential to be a therapeutic target in both cancer cells and CSCs. Novel therapeutic strategies for canine mammary carcinoma are expected to benefit to human breast carcinoma as well., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Michishita, Ochiai, Nakahira, Azakami, Machida, Nagashima, Nakagawa and Ishiwata.)

Previously, we reported that while low-dose-rate (LDR) gamma-ray exposure to 20 mGy/day for the entire gestation period (gestation days 0-18) did not result in any significant effect in B6C3F1 pups up to 10 weeks of age when compared to the non-irradiated controls, exposure to medium-dose-rates (MDR, 200 and 400 mGy/day) resulted in growth retardation and gonadal hypoplasia, in addition to delayed ossification (only at 400 mGy/day). In the present work, we investigated the late effects of continuous in utero exposure to gamma rays at LDRs (0.05, 1.0 and 20 mGy/day) and at an MDR of 400 mGy/day, on life span, causes of death, neoplastic and non-neoplastic disease incidences in B6C3F1 mice. Reproductive parameters such as litter size and weaning rates was not significantly different among the LDR groups, but was significantly decreased in the MDR group, when compared to the non-irradiated controls. Mean life spans were not significantly different among the LDR exposed groups compared to the non-irradiated controls, whereas the life spans of those exposed to the MDR were significantly shorter than the non-irradiated controls. There was no significant difference in tumor spectra between the non-irradiated and LDR nor MDR irradiated groups. In mice exposed to MDR in utero, the over-all incidence rates shifted with increased incidences in the number of neoplasms of liver (both sexes) and endocrine (adrenals, pituitary and ovaries in females) origin with corresponding decreases in the incidence of malignant lymphomas (both sexes) and lung neoplasms (males). Multiple primary neoplasms were significantly increased only in females exposed to MDR. Results show that B6C3F1 mice exposed to gamma-rays in utero at LDRs of 0.05, 1 and 20 mGy/day for the entire gestation period (18 days) does not significantly alter lifespan, cause of death, neoplasm incidence rates and tumor spectra., (©2022 by Radiation Research Society. All rights of reproduction in any form reserved.)

The effects of radiation exposure on germ cells and the gonads have been well studied at acute high-dose exposures, but the effects of chronic low-dose-rate (LDR) irradiation, particularly relevant for radiation protection, on germ cells and the gonads are largely unknown. Our previous study revealed that chronic exposure of mice to medium-dose-rate (MDR, 200 or 400 mGy/day) gamma-rays in utero for the entire gestation period (18 days) induced only a mild degree of general growth retardation, but with very drastic effects on the gonads and germ cells. In the current study, we further investigated the histomorphological changes in the gonads and the number of germ cells from gestation day (GD) 18 fetuses irradiated with MDR throughout the entire gestation period. The germ cells in the testes and ovaries of the MDR-irradiated fetuses were almost obliterated. Gestation day 18 fetuses exposed to LDR (20 mGy/day) radiation for the entire gestation period showed decreases in the number of the germ cells, which were not statistically significant or only marginally significant at most. Further investigations on the effects of LDR irradiation in utero using more sensitive methods are necessary., (©2021 by Radiation Research Society. All rights of reproduction in any form reserved.)

A Do-Not-Attempt-Resuscitation (DNAR) order solely precludes performing cardiopulmonary resuscitation (CPR) following cardiopulmonary arrest. A patient's personal status is known to influence a range of clinical practices, not only CPR, when a DNAR order is given. We assessed whether the absence of supporting relatives or a diagnosis of dementia can influence nurses' perceptions of clinical practices for elderly patients with non-malignant and chronic diseases. A vignette-based questionnaire was used to evaluate nurses' beliefs both before and after issuance of a DNAR order. Three vignettes were developed: the control vignette described an 85-year-old woman with repeated heart failure, the second and third incorporated a lack of relatives and a dementia diagnosis, respectively. The survey assessed the approach of nurses to 10 routine medical procedures, including CPR, clinical laboratory testing and nursing care, using a 5-base Likert-scale, for six vignette scenarios. A questionnaire was completed by 186 nurses (64% response). The pre-DNAR non-relative vignette showed significantly lower scores for CPR, indicating a deterioration in willingness to perform CPR, compared to the pre-DNAR control (median [interquartile]; 3 [2-4] and 4 [3-4] in the non-relative and control vignettes, respectively, p < 0.001). No significant differences were observed between the dementia and control vignettes. Absence of contactable relatives and resultant lack of communication can diminish the perception of nurses regarding the provision of CPR, even when a DNAR does not exist. This result suggests a necessity for comprehensive training all medical staff about issuance of DNAR orders and what care should be provided thereafter.

Cancer consists of heterogeneous cells that contain a small population of cells that possess stem cell properties; these cells, referred to as cancer stem cells (CSCs) or tumor-initiating cells, are involved in tumor progression and metastasis. Using a sphere-forming assay, canine mammary CSCs were found to be similar to human breast CSCs. Metabolic reprogramming has been recognized as a hallmark of various cancers. However, the significance of cellular metabolism in CSCs remains unclear. The aim of this study was to define the metabolic characteristics of CSCs derived from canine mammary tumors and gain an understanding of the maintenance of stemness. We identified metabolite profiles of canine mammary adenocarcinoma cell lines using gas chromatography-mass spectrometry. Metabolites were extracted from both adherent and sphere-forming cells derived from three cell lines. Sphere-forming cells were separated from adherent cells using an orthogonal, partial least-squares discriminant analysis. Sphere-forming cells were found to contain high levels of the amino acids alanine, glycine and proline compared with adherent cells. They also had high levels of palmitoleate, palmitate and dihomo-gamma-linolenic acid compared with adherent cells. In a sphere-forming assay, palmitate increased the number of spheres for all cell lines. These results indicate that the sphere-forming cells derived from canine mammary adenocarcinoma cell lines have specific metabolic profiles that may be useful for the development of CSC-specific therapies targeting metabolic pathways and potential stemness biomarkers; these results also clarify the maintenance of stemness in canine mammary CSCs.

Cancer stem cells or tumor-initiating cells (TICs) are a small subpopulation of cells that have the capacity to self-renew, differentiate and initiate tumors. These cells may function in tumor initiation, aggression and recurrence. Whether spheres derived from canine rhabdomyosarcoma cells have stem cell-like properties is unclear. We induced sphere formation in the canine rhabdomyosarcoma cell lines, CMS-C and CMS-J, and characterized the spheres in vitro and in vivo. Sphere-forming cells were more resistant to vincristine, mitoxantrone and doxorubicin than adherent cells. Xenograft transplantation demonstrated that 1 × 10 3 sphere-forming cells derived from CMS-C were sufficient for tumor formation. The sphere assay showed that the sphere-forming cells were present in these tumors. These results suggest that the spheres derived from canine rhabdomyosarcoma cells may possess characteristics of TICs. This study provides the foundation for elucidating the contribution of TICs to rhabdomyosarcoma tumorigenesis.

A 35-mo-old spayed female mixed-breed cat with continuous vomiting, emaciation, and abdominal distention for 2 wk was presented to a private veterinary clinic for evaluation. At 71 d after the initial visit, the cat died with anemia, jaundice, and hypoalbuminemia, and was subjected to autopsy. Grossly, numerous firm masses, 0.5-2.5 cm diameter, were randomly located in the left lobe of the pancreas. Histologic examination revealed that the pancreatic mass consisted of 2 tumor cell types: mostly small round cells with a minority of epithelial cells. The small cells were arranged in nests of various sizes, which were separated by thin fibrous stroma, and had small, round, hyperchromatic nuclei, scant cytoplasm containing argyrophilic granules, and often formed rosettes. The epithelial cells formed luminal structures. Metastases were observed in the liver, greater omentum, and pancreatic, gastric, pulmonary, and mediastinal lymph nodes. Immunohistochemical examination revealed that the small cells were positive for vimentin, neuron-specific enolase, chromogranin A, cytokeratin (CK) AE1/AE3, and trypsin, whereas the epithelial cells were positive for AE1/AE3, trypsin, CK19, and nestin. Ultrastructurally, the small cells contained abundant electron-dense granules, ~200 nm diameter, whereas the epithelial cells had apical microvilli and numerous zymogen granules, ~300 nm diameter. These findings indicated that the tumor was a pancreatic neuroendocrine carcinoma with exocrine differentiation and systemic metastases.

A 3-y-old male miniature Dachshund was presented with an ~0.8 cm diameter mass in the right mandibular region. Fourteen months later, the mass was 5 × 4 × 3 cm. Grossly, the mass was encapsulated and was homogeneously gray-white on cut surface. Microscopically, the mass was composed of large, round to polygonal tumor cells that were arranged in solid nests and cords separated by a fibrovascular stroma. Tumor cells had large, round, hypochromatic nuclei containing large prominent nucleoli and abundant eosinophilic cytoplasm containing dark blue granules visible with phosphotungstic acid-hematoxylin stain. Metastasis was observed in the mandibular lymph node. Immunohistochemically, tumor cells were positive for CK AE1/AE3, low-molecular-weight CK (CAM5.2), E-cadherin, mitochondria ATPase beta subunit, and S100, but were negative for vimentin, carcinoembryonic antigen, p63, CK14, CD10, and chromogranin A. Ultrastructurally, tumor cells contained numerous mitochondria. Therefore, the tumor was diagnosed as an oncocytic carcinoma of the mandibular gland.

During artificial insemination of an 18-year-old female Japanese Black cow, a mass that was of a hen's egg size was found in the vagina. On necropsy, the firm mass, measuring approximately 3.5 × 3.5 × 3.0 cm, was located at the superior region of the vagina. The cut surface of the mass was gray-white in color with occasional necrotic or hemorrhagic areas. Histologically, the mass was composed of tumor cells arranged in solid nests of various sizes with an occasional tubular structure separated by a delicate fibrovascular stroma. The tumor cells had a hypochromatic nucleus and abundant, faintly eosinophilic cytoplasm. The tumor cells contained diastase-sensitive periodic acid-Schiff positive granules. Immunohistochemically, tumor cells were positive for cytokeratin AE1/AE3, CAM5.2 and carcinoembryonic antigen, but not for vimentin, p63, estrogen receptor-α, progesterone receptor, α-smooth muscle actin, neuron-specific enolase, S-100 protein and chromogranin A. On the basis of these findings, the tumor was diagnosed as a clear cell carcinoma of the vagina.

Feline mammary carcinomas are characterized by rapid progression and metastases. Vascular endothelial growth factor (VEGF) is a key regulator of tumor angiogenesis, proliferation and metastasis. The present study aimed to investigate the effects of a single drug therapy of bevacizumab on a xenograft model of feline mammary carcinoma expressing VEGF protein. Bevacizumab treatment suppressed tumor growth by inhibiting angiogenesis and enhancing apoptosis; however, it did not affect the tumor proliferation index. Thus, bevacizumab had anti-tumor effects on a xenograft model, and this may be useful for the treatment of feline mammary carcinoma.

Ganglion cell-like (GL) cells reside in the dermis of the ventral skin of mature male Djungarian hamsters (Phodopus sugorus) and express androgen receptor (AR). To assess whether GL cells have androgen-dependent behavior, we evaluated the histologic changes of GL cells after gonadectomy. Five male and 5 female hamsters were gonadectomized at the age of 4 wk and necropsied 14 wk later. The number, distribution, and proliferative activity of GL cells in the thoracoabdominal and dorsal skins were evaluated histologically and compared with those of corresponding intact animals. GL cells were more numerous, were distributed throughout the skin more widely, and had higher proliferative activity in the intact male hamsters than in their gonadectomized counterparts. Similar trends regarding these 3 parameters were seen in ovariectomized compared with intact female hamsters and between intact male and intact female hamsters. These results suggest that the GL cells of Djungarian hamsters demonstrate sex-associated differences in their distribution and proliferative activity and that androgen may be involved in the development of these cells.

Although the morbidity of canine prostate cancer is low, the majority of cases present with resistance to androgen therapy and poor clinical outcomes. These pathological conditions are similar to the signs of the terminal stage of human androgen-independent prostate cancer. The co-chaperone small glutamine-rich tetratricopeptide repeat-containing protein α (SGTA) is known to be overexpressed in human androgen-independent prostate cancer. However, there is little information about the structure and function of canine SGTA. In this study, canine SGTA was cloned and analysed for its ability to suppress androgen receptor signalling. The full-length open reading frame (ORF) of the canine SGTA gene was amplified by RT-PCR using primers designed from canine-expressed sequence tags that were homologous to human SGTA. The canine SGTA ORF has high homology with the corresponding human (89%) and mouse (81%) sequences. SGTA dimerisation region and tetratricopeptide repeat (TPR) domains are conserved across the three species. The ability of canine SGTA to undergo homodimerisation was demonstrated by a mammalian two-hybrid system and a pull-down assay. The negative impact of canine SGTA on androgen receptor (AR) signalling was demonstrated using a reporter assay in androgen-independent human prostate cancer cell lines. Pathological analysis showed overexpression of SGTA in canine prostate cancer, but not in hyperplasia. A reporter assay in prostate cells demonstrated suppression of AR signalling by canine SGTA. Altogether, these results suggest that canine SGTA may play an important role in the acquisition of androgen independence by canine prostate cancer cells., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A small population of cells known as tumor-initiating cells (TICs), which have the capacity to self-renew, differentiate, and form tumors at high frequency, has a potential role in tumor initiation, aggression, and recurrence. In human breast cancers, TICs are identified by surface markers, such as CD44 and CD24, and an aldefluor assay based on aldehyde dehydrogenase activity (ALDH(+)) using flow cytometry. However, the usefulness of surface markers CD44 and CD24 and ALDH activity in feline mammary carcinomas remains largely elusive. We attempted to identify CD44(+)CD24(-) and ALDH(+) cells using 8 feline mammary carcinoma cell lines, including FKNp, which was obtained from a primary lesion, and the capacity to generate tumor nodules was analyzed in immunodeficient mice injected with ALDH(+) FKNp-derived cells. The CD44(+)CD24(-) and ALDH(+) cells were detected in all cell lines derived from feline mammary carcinomas. Xenograft transplantation into immunodeficient mice demonstrated that as few as 1 × 10(2) ALDH(+) cells could initiate tumor growth in 1 out of 4 mice, while 1 × 10(3) ALDH(+) cells initiated tumor growth in 5 out of 6 mice. However, 1 × 10(3) ALDH(-) cells failed to initiate tumors in all the tested mice. ALDH(+)-derived tumors contained both ALDH(+) and ALDH(-) cells, indicating that ALDH(+) FKNp-derived cells had higher tumorigenicity than ALDH(-) cells. These results suggest that TICs may exist in feline mammary carcinomas, and further characterization of CD44(+)CD24(-) and ALDH(+) cells is needed to define novel therapies targeted against TICs. This study provides the foundation for elucidating the contribution of TICs in tumorigenesis., (Copyright © 2013 Elsevier B.V. All rights reserved.)

An invasive micropapillary carcinoma (IMC) occurred in the buccal skin of an 18-year-old female cat. Histologically, the tumor had a honeycomb pattern characterized by clusters of neoplastic epithelial cells that were surrounded by empty clear spaces and lined with fibrocollagenous stroma. On immunohistochemistry, the neoplastic cells were positive for cytokeratin (clone CAM5.2; pancytokeratin, clone AE1/AE3) and carcinoembryonic antigen (CEA) but negative for cytokeratin 14, vimentin, S100, smooth muscle actin, and p63. The CEA-positive staining reaction was present along the outermost rim of the neoplastic cell clusters consistent with an "inside-out" immunoreactivity pattern. Examination of the tumor cells by electron microscopy revealed microvilli on the outermost rim of neoplastic cells that were directed toward the surrounding vacant space. Based on histomorphological characteristics, the neoplasm was defined as an IMC of "pure-type." The location site and immunohistochemical features suggest the tumor was most likely derived from the apocrine sweat glands in the buccal skin.

A lipid-rich carcinoma of the mammary gland was diagnosed in a female Djungarian hamster (Phodopus sungorus), which was kept as an indoor pet. The animal underwent surgery for a primary tumor arising in the mammary gland at the age of 16 months, and also for a recurrent tumor 6 months later. Histologically, the primary neoplasm was composed of 2 different cell populations: nonvacuolated glandular neoplastic cells with moderate atypia, and vacuolated neoplastic cells with marked atypia. Transition from the nonvacuolated glandular cells to the vacuolated cells was frequently seen. The recurrent neoplasm was composed predominantly of vacuolated neoplastic cells that often invaded the surrounding soft tissue. The cytoplasmic vacuoles contained neutral lipids, as confirmed by oil red O and Nile blue staining. The vacuolated neoplastic cells were immunopositive for cytokeratin and negative for vimentin, alpha-smooth muscle actin, p63, estrogen receptor alpha, and androgen receptor. Presumably, this high-grade, lipid-rich mammary carcinoma had developed from a low-grade mammary adenocarcinoma.

The stomach is constantly exposed to mechanical and chemical stresses. Under persistent damages, epithelial cell proliferation is required to maintain mucosal integrity. Nevertheless, which ligand system(s) is physiologically involved in gastric defense remains unclear. Herein, we provide evidence that HGF is a key "natural ligand" to reverse gastric injury. The injection of cisplatin in mice led to the loss of HGF in the gastric interstitium, associated with the decrease in proliferating epithelium and the progression of mucotitis. When c-Met tyrosine phosphorylation was abolished by anti-HGF IgG, mucosal cell proliferation became faint, leading to delayed recovery from mucotitis, and vice versa in cases of HGF supplementation. Our findings indicate that: (1) HGF/c-Met signal on mucosa is needed to restore gastric injuries; and (2) the loss of local HGF leads to manifestation of gastric lesions. This study provides a rationale that explains why HGF supplement is useful for reversing gastric diseases.

Background: The radicular pain caused by disc herniation can be explained by two mechanisms: the compression of the nerve root by the herniated disc or the irritation of the nerve root due to chemical factors. Percutaneous laser disc decompression (PLDD) was introduced for the treatment of lumbar disc hernias in the 1980s. Decompression of the nerve root is assumed to be an effective therapeutic mechanism for PLDD. However, laser irradiation might reduce the chemical factors that cause nerve root irritation by altering intra-disc proteins. We used nerve conduction velocities (NCV) and levels of two chemical factors to evaluate the differences between the two groups in this in vivo study., Methods: All rabbits had the nerve root in contact with the leakage from the nucleus pulposus. One group underwent laser irradiation for the leaking nucleus pulposus including the incision site of the disc and nucleus pulposus itself. The levels of two chemical factors, prostaglandin E2 and phospholipase E2, in the intervertebral disc were measured before and after laser irradiation., Results: NCV in the laser-irradiated group was significantly faster than in the non-laser-irradiated group. The levels of chemical factors were significantly reduced after laser irradiation., Conclusions: One of the mechanisms thought to be responsible for PLDD's effectiveness is a decrease in the chemical factors through protein alteration in the intervertebral disc by laser irradiation.

To create a cell line with controlled and specific secretion of beta-endorphin, a new fusion gene was constructed by joining human beta-endorphin coding sequence to part of NL1 gene. HEK293 cells carrying Tet-on system transfected with this fusion gene secreted beta-endorphin in a dose-dependent manner upon doxycycline administration. These findings suggest that this system can direct the controlled secretion of any peptide hormones such as beta-endorphin.

Computed tomography potentially offers the most accurate noninvasive means of estimating in vivo volumes. Contiguous 5 and 10-mm-thick CT scans were obtained through phantom and neonatal cranium. Cross-sectional areas were calculated for each individual scan and volumes then determined with summation-of-areas technique. The indirect intracranial volume measurement technique was then used to compare hydrocephalic and non-hydrocephalic intracranial and ventricular volumes in nine neonates. Our findings show that intracranial volumes of hydrocephalic neonates with head circumference of more than 39 cm, have 1.97 times larger than control group. The ratios of lateral ventricle versus intracranial volume are 0.57 +/- 0.2 in hydrocephalic babies and 0.0062 +/- 0.001 in control babies, respectively(p < 0.005).