The development of the skull base of 1000 cases was studied with skull radiographies. The length of the skull base and cranium were measured and the indexes were calculated. The same measurement and calculation were used to determine the width of the skull base and the cranium. The main results are as follow, The width and length of the skull base are similar in both sexes before 7 years of age, larger in boys than in girls after 7 years and almost never increase at 17 years. Before 14 years, the width of the skull base increases quicker than that of the cranium. Therefore, the indexes are also increased with age, but with no longer increase with age after 14 years. The index of length of the craniumskull base does not increase with age because the development curves of the length of the cranium and skull base are similar.

A comparative analysis of bone age and stature development between 93 cases of mental retardation and 305 cases of mentally ormal children was made. About 50% of the cases mental retardation were associated with stature depression, The delay of bone age was longer in the mental retardation group than in the control group. The more severe mental retardation, the higher frequency the stature depression. Stature depression was more often seen in the areas where the environment and economic conditions are poor and in boys than in girls. The younger the mote frequency of the stature depression. When patients reached the age of puberty, some of the bone age delay and stature depression tended to get mild or could return to normal. Integrating the epidemiological investigation with the clinicoradiologic examination, we found that poor environment and undernutrition are significant factors for mental retardatio.

Objective To study the CT and MRI features of cystic brain metastases. Methods 26 cases of cystic brain metastases proved by clinicopathology were presented.There were13 males and 13 females with an average age of 52.7 years.CT studies were obtained in 15 cases,while MR studies were done in 13 cases.11 cases had CT and/or MRI contrast enhancement studies. Results According to the shape of the wall of cystic brain metastases,48 tumors in 26 cases were classified into three types: irregular,nodular,regular type.The wall demonstrated iso-or slightly high density on CT and iso-or slightly low intensity on MR T_1WI and T_2WI,while the hydatid fluid showed slightly high intensity on MR T_1WI and high intensity on T_2WI and iso-or slightly high density on CT compared to CSF.The tumors showed circular reinforcement on enhanced CT or MRI,with nodular enhancement in some cases. Conclusion Cystic brain metastases have mutiple types and should be differentiated from brain abcess and other cystic brain parenchamal tumors.Multi-direction enhanced MRI is helpful to diagnosis.

Objective To evaluate the clinical significance of the distribution characteristics and thickness of lumbosacral canal fat in normal adults,and to assess the relevant factors of the fat thickness.Methods Sagittal images of lumbosacral canal fat on MRI T_(1)WI in 260 normal adults were observed.The distribution characters of the fat were studied on mid-sagittal plane.The thickness of anterior and posterior epidural fat and the canal diameter were measured and analyzed.Results The anterior epidural fat showed a barred or crescent shape and segmental distribution,while the posterior epidural fat had a segmental distribution with a spindle shape.The thickness of the epidural fat varied at different levels.The fat thickness showed no statistical difference between men and women or every age group.Positive linear correlation occurred between spinal canal diameter or obesity index and the thickness of posterior epidural fat.Conclusion The distribution characteristics and thickness of the lumbosacral canal epidural fat can be used as index in diagnosing some spinal canal diseases.

Objective To evaluate the clinical value of the distribution characters and thickness of fat in thoracic canal in normal adults,and to assess the relational factors of the fat thickness.Methods The distribution characters of the thoracic canal fat in 268 normal adults were studied in mid-sagittal plane on MR T_1WI.The thickness of epidural fat and the canal diameter were measured and analyzed.Results Thoracic canal fat on mid-sagittal plane was only found in posterior epidural space,mainly appearing as segmental distribution. Continuous barred or spindle shape of the fat was also seen in some cases.The thickness of fat varied at different thoracic levels.There was no statistic significance between men and women or every age group about the fat thickness.Positive linear correlation occurred between spinal canal diameter or obesity index and the fat thickness.Conclusion The distribution characters and thickness of the thoracic epidural fat can be used as references in diagnosing some spinal canal diseases.

The distal femoral epiphyses of 18 human foetus and 10 children were studied by microangiographic and histological methods. The results showed that only the articular cartilage is avascular. Characteristic of vascularity in the chondroepiphyses is that the blood vessels coming from inter-condylar fossa are distributed in the center of chondroepiphyses, those coming from medial and lateral aspects of the condyles are distributed in the outer part of the condyles and those closing to epiphyseal plate mainly come from the area superior to the patellar surface and the area superior to the inter-condylar fossa. The secondary center of ossification first takes place around cartilage canal. The increase of the ossification center is faster in the areas adjacent to blood vessels than the areas far from blood vessels. The blood vessels within cartilage canals in the chondroepiphyses transform to epiphyseal vessels which remained as the blood supply to the ossification center during ossification process. Before 2 years of age, the blood vessels supplying the ossification center are 3-5 vessels coming from inter-condylar fossa. After 2 years of age, the blood vessels coming from the area superior to the patellar surface begin to supply the ossification center. After 5 years of age, the blood vessels coming from lateral aspects of the condyles also take part in the supply of the ossification center.

The structure and the blood supply of perichondral ring of human being and rabbits in developing period were studied by microangiographic and histological methods. Perichondral ring is situated around the epiphyseal disc and metaphysis and consists of osseous ring, zone of mesenchymal cell, which contains fairly abundant blood vessels derived from the metaphyseal periosteum and perichondrium. The perichondrium is thick and also contains abundant vessels which connect epiphyseal and metaphyseal circulations in the extra-osseous and part of which passes through the zone of mesenchymal cell to supply the epiphyseal disc. Role of perichondral ring in the development period of bones were discussed.

Objective To investigate the clinical and MR features of fungal encephalopyosis and fungal granuloma.Methods The clinical and MR data of 10 cases with fungal encephalopyosis and fungal granuloma confirmed by surgical pathology or clinical serum were analyzed retrospectively.Then we analyzed the clinical conditions,MR signals,lesion enhancement,DWI and MRS performance characteristics of the 10 cases.Results Six cases were fungal encephalopyosis,among which 2 cases occurred in the sella turcica after surgery which located in and above the sella turcica.2 cases occurred in the frontal lobe after frontal surgery and 1 case of them was multiple encephalopyosis.2 cases of encephalopyosis without operation history were located in the left frontal lobe and right cerebellum respectively.The abscess walls of these cases were thin and showed high tension.Furthermore,it had annular significant signal enhancement and high signal in DWI scan.One case of huge fungal granuloma located in the frontal lobe and into the sinuses which showed uneven signal enhancement. The Cho level was significantly increased.Three cases of cryptococcal granuloma showed multiple lesions located in the bilateral basal ganglia region and 2 out of them accompanied with cephalomeningitis.Conclusion The MR performance of fungal encephalopyosis was quite similar with bacterial brain abscesses,which makes the differential diagnosis difficult.The brain fungal granuloma MRS may display a significant increase of Cho level which might be related with gliosis.It shows certain characteristics of brain MR performance of cryptococcal granuloma which are multiple lesions,preferential distribution of basal ganglia region and accompanying cephalomeningitis.

Objective To investigate the imaging manifestations and clinical features of hepatic and renal angiomyolipoma. Meth-ods The clinical data and imaging findings of hepatic and renal angiomyolipoma in a 51-year-old woman was retrospectively ana-lyzed with literature review. Results CT scan showed a large polymorphous hypodense mass in the right lobe of liver. After contrast -enhanced CT scan, the mass was enhanced gradually from periphery to ceritre. Bilateral kidneys obviously enlarged and appeared as alveolate appearance mixed density with spotty and stripped fat structures. At contrast-enhanced scan, the normal structures of cor-tex and medulla were disappeared, the alveolate walls were enhanced obviously. The arteries and veins of bilateral kidneys were com-pressed and displaced. Conclusion The imaging features of liver and kidney are of certain characteristic compared with other benign and malignant masses,but the final diagnosis of it is still depending on pathology mostly.

Objective To study the clinical manifestat ions, MR diagnosis and differential diagnosis of sacral meningeal cyst.Methods 25 patients with sacral meningeal cyst proved by operation and pathology, 9 cases of male, 16 cases of female; the age ranged fro m 18 to 56 years old, average age is 40.3. All cases were performed on MR examin ation. Results The shape of cysts in 19 cases were elliptic,long marsupial shape in 3 cases,irregular in 1 case,string shap in 2 cases.The edge of cysts is clear and the wall of cysts is very thin.MR signal in tensity of fl uid in sacral meningeal cysts exhibits similarity to cerebrospinal fluid,which s hows uniform low signal in T 1WI and high signal in T 2WI.There are 8 cases sc an whose MR signal of cysts fluid is much higher than that of cerebrospinal flui d in T 2WI. In 7 cases thin strip nerve root can be found through the cysts in T 1WI and T 2WI. The antrast enhancement was made in 8 cases and there were no any enhancement both in content and wall of cyst.Conclusion MRI is one of the best examing methods for dia gnosiing of sacral meningeal cyst. Correct mastery of MR manifestations can not only help to give right dignosis, but also provide guidance for choices of clini cal treatment.