Magnetic Resonance Enhancement Pattern as a Predictor of Cement Volume in Vertebroplasty Procedures for Osteoporotic Fractures

PURPOSE: To identify the differences between injected cement volumes during vertebroplasty procedures according to the enhancement pattern of pre-procedure magnetic resonance imaging (MRI) findings. MATERIALS AND METHODS: Thirty-two patients who underwent 52 vertebroplasty procedures as well as pre-procedure contrast-enhanced spine MRI in the authors' institution were reviewed retrospectively. The 52 procedures were divided into two groups according to different enhancement patterns shown by pre-procedure MR imaging [E(+) and E(−)]. The volumes of the enhancing/non-enhancing portions of the fractured vertebral body shown by pre-procedural MR imaging were calculated and compared to the volumes of the injected cement during the vertebroplasty procedures. RESULTS: The 52 injections included 28 (56%) in Group E(+) and 24 (44%) in Group E(−). The actual volume ratio of the injected cement to the volume of the non-enhanced or enhanced region calculated based on the contrast-enhanced MRI was 0.22 ± 0.11 (cc/cm³) in the E(+) group and 0.93 ± 0.62 (cc/cm³) in the E(−) group. The average amount of injected cement was significantly different between Group E(+) and Group E(−) (P < 0.001). In addition, the ratio of the injected cement amount to the volume of the enhanced or non-enhanced portion based on the contrast-enhanced MRI in Group E(−) was significantly higher than that of Group E(+) (P < 0.001). CONCLUSION: Different enhancement patterns shown by pre-procedure MRI can predictors of the injected cement volume during vertebroplasty procedures for osteoporotic fractures.

Spontaneous Resolution of Chronic Subdural Hematoma : Close Observation as a Treatment Strategy

OBJECTIVE: Chronic subdural hematoma (cSDH) is common condition in neurosurgical field. It is difficult to select the treatment modality between the surgical method and the conservative method when patients have no or mild symptoms. The purpose of this study is to provide a suggestion that the patients could be cured with conservative treatment modality. METHODS: We enrolled 16 patients who had received conservative treatment for cSDH without special medications which could affect hematoma resolution such as mannitol, steroids, tranexamic acid and angiotensin converting enzyme inhibitors. The patients were classified according to the Markwalder's Grading Scale. RESULTS: Among these 16 patients, 13 (81.3%) patients showed spontaneously resolved cSDH and 3 (18.7%) patients received surgery due to symptom aggravation and growing hematoma. They were categorized into two groups based on whether they were cured with conservative treatment or not. The first group was the spontaneous resolution group. The second group was the progression-surgery group. The mean hematoma volume in the spontaneous resolution group was 43.1 mL. The mean degree of midline shift in the spontaneous resolution group was 5.3 mm. The mean hematoma volume in the progression-surgery group was 62.0 mL. The mean degree of midline shift in the second group was 6 mm. CONCLUSION: We suggest that the treatment modality should be determined according to the patient's symptoms and clinical condition and close observation could be performed in patients who do not have any symptoms or in patients who have mild to moderate headache without neurological deterioration.

Mucoepidermoid Carcinoma with Distant Metastases to the Kidney, Adrenal Gland, Skull and Gluteus Maximus Muscle: a Case Report

INTRODUCTION: Distant metastases of mucoepidermoid carcinoma (MEC) are reported with the most common sites being the soft tissue of skin, lung, liver, and bone. We report here a very rare case of MEC with multiple metastases to the kidney, adrenal gland, skull and gluteus maximus muscle. CASE REPORT: A 63-year-old male patient presented with left-sided headache. Radiologic evaluations including CT and MRI showed ill-defined soft tissue lesion involving the left infratemporal fossa and left sphenoid sinus, and multiple enlarged lymph nodes in neck and mediastinum. PET-CT demonstrated multiple hypermetabolic lesions in and around the left kidney, left adrenal gland, right ischium, right gluteus maximus and skull base. These lesions were confirmed as MEC with multiple metastases through biopsy. DISCUSSION: Only one case of metastasis to the skull has been previously reported, and moreover, there has not been a case of metastatic MEC to the kidney, adrenal gland and gluteus maximus muscle so far in the medical literature. It is important to acknowledge the possibility of every unusual MEC metastases, since the presence of metastasis has statistically significant influence on the survival of MEC.

Prosthetic rehabilitation of partially edentulous patient after hemimandiblectomy: Case report / 대한치과보철학회지

Loss of continuity of the mandible destroys the balance and symmetry of mandibular function, leading to altered mandibular movements and deviation of the residual fragment towards the resected side. Apart from deviation, other dysfunctions include difficulty in swallowing, speech, mandibular movements, mastication, and respiration are accompanied. In general, surgical reconstruction is considered first then proceeds to the prosthetic restorations. However, patients with systemic disease such as BRONJ (Bisphosphonate related osteonecrosis of the Jaw), surgical reconstruction may be limited. Thus, the prosthetic restoration remains as the only resort. Numerous prosthetic methods are employed to minimize deviation and to improve masticatory efficiency, function and esthetics. If a removable partial denture is the selected treatment modality, maximum stability of the partial denture base may be accomplished with a functional impression procedure by means of eliminating lateral and horizontal forces caused by the functional movements of the lips, cheeks and tongue. Also, Twin occlusion is used to obtain a favorable occlusal relationship and check support for esthetics. The purpose of this case report is to demonstrate how neutral zone impression technique and twin occlusion scheme were applied to restore a hemi-mandiblectomy patient with BRONJ syndrome to achieve satisfactory results in functional and esthetic aspects.

Rapid Regression of White Matter Changes in Hypoglycemic Encephalopathy

PURPOSE: In a previous report, it took several days for white matter lesions to regress in hypoglycemic encephalopathy. We present a case of rapid diffusion-weighted image (DWI) changes in hypoglycemic encephalopathy. CASE REPORT: A 58-year-old male patient was found semi-comatous with the only abnormality in his laboratory tests showing hypoglycemia (44 mg/dL). After rapid correction of glucose level, immediate brain DWI showed bilateral subcortical white matter lesions. After about 5 hours, follow-up DWI showed resolved subcortical white matter lesions, with newly-appeared bilateral fronto-temporo-parietal cortical lesions. CONCLUSION: Both white matter and cortex involvement in hypoglycemic encephalopathy has been shown in several reports, but rapid regression of white matter changes in hypoglycemic encephalopathy has been rarely reported. It is important to know that MR imaging changes in hypoglycemic encephalopathy can be made as quick as just a few-hour-long.

Aquagenic Urticaria: A Report of Two Cases

Aquagenic urticaria is a rare form of physical urticaria, in which contact with water evokes wheals. A 19-year-old man and a 4-year-old boy complained of recurrent episodes of urticaria. Urticaria appeared while taking a bath or a shower, in the rain, or in a swimming pool. Well-defined pin head to small pea-sized wheals surrounded by variable sized erythema were provoked by contact with water on the face, neck, and trunk, regardless of its temperature or source. Results from a physical examination and a baseline laboratory evaluation were within normal limits. Treatment of the 19-year-old man with 180 mg fexofenadine daily was successful to prevent the wheals and erythema. Treatment with 5 ml ketotifen syrup bid per day resulted in improvement of symptoms in the 4-year-old boy.

Cystic Embryonal Sarcoma of the Kidney: Report of a Case with US and CT Findings

Here we report a case in a 41-year-old woman histologically proven cystic embryonal sarcoma of the kidney, with emphasis on the imaging findings and pathological features. A large lobulated solid mass in the cystically dilated pelvocalyceal region was accompanied with hydroureter as depicted on both ultrasound and contrast-enhanced CT images.

Diffuse Pneumocephalus : A Rare Complication of Spinal Surgery

The common etiologies of pneumocephalus, presence of air in the intracranial cavity, are trauma and cranial surgery. Pneumocephalus after spinal surgery is an unusual postoperative complication. We report the case of a male 59-year-old man who developed a pneumacephalus after posterior lumbar surgery for spinal stenosis. Intraoperatively, a cerebrospinal fluid leak following a dural tear was noted and immediately repaired. The next day, the patient complained of headache and dizziness. Head and lumbar computed tomography scans revealed significant air in the frontal region, several cisterns, intraventricle, and extra-dural area in the spine canal. Symptoms were spontaneously resolved within 2 weeks with conservative management.

Anatomic Illustrations of Cranial Ultrasound Images Through the Posterior Fontanelle in Neonates: Objective Analysis of Oblique Sonographic Scans using MRI and a Reconstruction Program

PURPOSE: Neonatal cranial sonongraphy through the posterior fontanelle is more useful than through the anterior approach for the evaluation of posterior brain structures. The aims of this study were to determine the appropriate neonatal cranial sonography scan planes through the posterior fontanelle, and to objectively evaluate the anatomy of neonatal cranial sonographic images. MATERIALS AND METHODS: Neonates who underwent cranial sonography and MRI including 3D-SPGR axial scans and showed normal features on both modalities were enrolled. We reconstructed MR images corresponding to sonongraphic planes, then constructed anatomic models of the neonatal cranial sonographic images using axial MRI as the standard reference on the same screen. RESULTS: We successfully created anatomic atlas that represents 8 oblique coronal and 4 oblique sagittal scans and planes that corresponded to the neonatal cranial sonographic images through the posterior fontanelle. CONCLUSION: The objective manner of this anatomic research provided standardized sonographic scan planes and created anatomic model through the posterior fontanelle. Cranial sonographic models through the posterior fontanelle using MRI and multi-planar reconstruction program will be helpful in the evaluation of sonographic anatomy and detection of abnormalities in the basal ganglia, thalamus and posterior part of the brain.

MR Findings Predictive of Intradiscal Leakage of Bone Cement in Vertebroplasty

PURPOSE: To evaluate the relation between pre-operative MR findings and intradiscal bone cement leakage. MATERIALS AND METHODS: Pre-operative MR and vertebroplasty were performed in 188 vertebral bodies, 376 superior and inferior cortical endplates and intervertebral discs of 126 patients. We analyzed the relation between endplate cortical injury and intradiscal linear low signal intensity lesions in the pre-operative MR images and measured intradiscal bone cement leakage on post-operative CT and fluoroscopy. RESULTS: Intradiscal bone cement leakage was found in 11.4% (43/376) of the cases. The incidence of endplate cortical injury in T1, T2 weighted MR images were 52.1% and 38.8%, respectively; the incidence of intradiscal linear low signal intensity lesions in T1, T2 weighted images were 11.2% and 24.2%, respectively. In relation with pre-operative MR findings and intradiscal bone cement leakage, the sensitivities of end plate cortical injury in T1 and T2 weighted images and intradiscal low signal intensity lesions in T1 and T2 weighted images were 100%, 95.3%, 39.5%, 86.5%, the specificities were 54.1%, 68.5%, 92.5%, 83.9%, the positive predictive values were 21.9%, 28.1%, 40.5%, 40.7%, the negative predictive values were 100%, 99.1%, 92.2%, 97.9%, and the accuracy were 59.3%, 71.5%, 86.4%, 84.0%. The incidence of intradiscal bone cement leakage was significantly increased when endplate cortical injury and intradiscal linear low signal intensity lesions were observed (p <0.001). CONCLUSION: Endplate cortical injury and intradiscal linear low signal intensity observed in pre-operative MR are useful findings in predicting intradiscal bone cement leakage.

MR Findings of Hypoxic Brain Damage: Relation to Time Elapse and Prognosis of Patients

PURPOSE: To describe MR imaging features of hypoxic brain damage in relation to time elapse and prog-nosis of patients. MATERIALS AND METHODS: We reviewed 19 MR studies of 18 patients with hypoxic brain damage. MR imaging studies were performed between 1 to 20 days after the hypoxic insults (mean 8.6 days). MR images were analyzed with regard to the locations of abnormal signal intensities, the presence of brain edema. And imaging findings were correlated with the time elapse after the insults and the prognosis of patients. RESULTS: On 19 cases of MR studies, abnormal high intensities on T2-weighted images were found in the basal ganglia (15, 78.9%), cerebral cortex (13, 68.4%), white matter (9, 47.4%), thalamus (6, 31.6%), cerebellum (4, 21.1%) and brainstem (1, 5.3%), respectively. Cerebral cortical involvement was typically bilateral and diffuse, but sometimes limited to the parieto-occipital area. The brainstem and cerebellar involvement was rare and in all cases, cerebral cortical lesions accompanied. Most of the white matter lesions were accompanied with cortical and deep gray matter lesions and found in subacute period(>6 days). The cortical high signal intensity lesions on T1-weighted image were found mostly in subacute stage, but in some cases involvement was also found in acute stage (< or =6 days). The cortical edema is found on 11 cases in acute and subacute stages. In cases of recovered consciousness, cortical involvement and edema on MR were rare. CONCLUSION: MR findings of hypoxic brain damage were various, but diffuse bilateral involvement of cortex and/or deep gray matter was found in most of the cases. White matter involvement was rarely found in acute stage and usually found in subacute stage. In cases of good pronosis, cortical involvement and edema were rare.

Comparative Study of Functional Magnetic Resonance Imaging by Global Scaling Analysis

PURPOSE: To evaluate the effect of global scaling analysis on brain activation for sensory and motor func-tional MR imaging study. MATERIALS AND METHODS: Four normal subjects without abnormal neurological history were included. Arm extension-flexion movement was used for motor function and 1 KHz pure tone stimulation was used for auditory function. Functional magnetic resonance imaging was performed at 3T MRI (GE, Milwaukee, USA) using BOLD-EPI technique and SPM2 was employed for data analysis. On data analysis, the brain activation images were obtained with and without global scaling by fixing other parameters such as motion correction and realignment. RESULTS: The difference in brain activation between no scaling and global scaling was not large in case of right upper extremity movement (p<0.000001). For auditory test, brain activation with global scaling showed larger activation than that of without global scaling (p<0.05). CONCLUSION: A caution must be taken into account when analyzing functional imaging data with global s-caling especially for functional study of small local BOLD signal change.

Comparison of the capsular width measured on ultrasonograph and MR image of the temporomandibular joint / 대한구강악안면방사선학회지

PURPOSE: To evaluate the reliability and clinical usefulness of ultrasonography in the temporomandibular joint (TMJ). MATERIALS AND METHODS: Parasagittal and paracoronal 1.5 T MR images and 7.5 MHz ultrasonographs of 40 TMJs in 20 asymptomatic volunteers were obtained. Disc position using MR imaging was evaluated and the distance between the lateral surface of mandibular condyle and the articular capsule using MR image and ultrasonograph of 27 TMJs with normal disc position was measured and compared. Intraobserver and interobserver measurements reliability was evaluated by using interclass correlation coefficients (ICC) and measurement error. Also, the distance measured on ultrasonographs was compared, according to mouth position and disc postion. RESULTS: The normal disc position was found in 27 of 40 asymptomatic joints. At the intraobserver reliability of measurement, ICC at the closed and open mouth position were 0.89 and 0.91. The measurement error was 0.4% and 0.5%. At the interobserver reliability, ICC at the closed and open mouth position were 0.92 and 0.81. The measurement error was 0.4% and 0.7%. At the TMJ with normal disc position, the distances between the lateral surface of mandibular condyle and the articular capsule measured on MR images and ultrasonographs were 2.0+/- 0.7 mm, 1.8+/-0.5 mm, respectively (p<0.05). On the ultrasonographs, the distances at open mouth position were 1.2+/-0.5 mm (p<0.05). At the TMJ with medially displaced disc, the distances at the closed and open mouth position were 1.3+/-0.3 mm and 0.9+/-0.2mm(p<0.05). CONCLUSION: The results suggest ultrasonography of TMJ is a reliable imaging technique for assessment of normal disc position.

Evaluation of compression ratios using JPEG 2000 on diagnostic images in dentistry / 대한구강악안면방사선학회지

PURPOSE: To find out the proper compression ratios without degrading image quality and affecting lesion detectability on diagnostic images used in dentistry compressed with JPEG 2000 algorithm. MATERIALS AND METHODS: Sixty Digora periapical images, sixty panoramic computed radiographic (CR) images, sixty computed tomographic (CT) images, and sixty magnetic resonance (MR) images were compressed into JPEG 2000 with ratios of 10 levels from 5 : 1 to 50 : 1. To evaluate the lesion detectability, the images were graded with 5 levels (1: definitely absent; 2: probably absent; 3: equivocal; 4: probably present; 5: definitely present), and then receiver operating characteristic analysis was performed using the original image as a gold standard. Also to evaluate subjectively the image quality, the images were graded with 5 levels (1: definitely unacceptable; 2: probably unacceptable; 3: equivocal; 4: probably acceptable; 5: definitely acceptable), and then paired t-test was performed. RESULTS: In Digora, CR panoramic and CT images, compressed images up to ratios of 15 : 1 showed nearly the same lesion detectability as original images, and in MR images, compressed images did up to ratios of 25 : 1. In Digora and CR panoramic images, compressed images up to ratios of 5 : 1 showed little difference between the original and reconstructed images in subjective assessment of image quality. In CT images, compressed images did up to ratios of 10 : 1 and in MR images up to ratios of 15 : 1. CONCLUSION: We considered compression ratios up to 5 : 1 in Digora and CR panoramic images, up to 10 : 1 in CT images, up to 15 : 1 in MR images as clinically applicable compression ratios.

Development of Transcutaneous Energy Transmission System for Implantable Devices / 의학물리

As a part of implantable device in body, a transcutaneous energy transmission system has been developed. It would be desirable to tansfer electrical energy to implantable devices transcutaneously. The distance between transcutaneous transformer windings are approximately equal to the thickness of the human's skin, nominally between 10~20 mm. Class-E resonant amplifier is used to drive a primary coil for high efficiency. Maximum current is above 50 mA at any frequency. The developed system shows that the circuit operates correctly at each frequency; 500 kHz, 1 MHz and 4 MHz.

Pilomatricoma in the Eyelid: A Case Report

The pilomatricoma (calcifying epithelioma of Malherbe) is a rare, benign, asymptomatic tumor arising from the hair follicular matrix cells. It is usually a solitary lesion and it is most commonly found on the face and upper extremities. This tumor can occur in patients of any age, but about 60% of pilomatricomas are found in those patients less than twenty years old. The radiologic features of this neoplasm have rarely been described in the literature; in particular, the CT findings of pilomatricoma originating from the eyelid have not been published in Korea. We report here on a case of pilomatricoma that occurred in 69-year-old female; she had a hard subcutaneous mass on her right eyelid with overlying bluish skin.

The Electrodiagnostic Findings of Sciatic Nerve Injury according to the Locations and Etiologies

OBJECTIVE: To reveal the pattern of involvement of the peroneal and tibial division in the sciatic nerve injury according to the locations and etiologies. METHOD: Fifty-four patients with sciatic nerve injuries were investigated. The relative involvement of peroneal dominant (PD) and tibial dominant (TD) were determined by needle electromyography, and the locations and etiologies of sciatic nerve injury were evaluated. Fifteen patients were followed up and the prognostic factors were investigated. RESULTS: The peroneal division was more severely affected in thirty-three cases (59.3%), tibial division was more in thirteen cases (24.1%), and there were nine cases (16.7%) equally affected. Fracture was the most common cause of sciatic nerve injury, and TD was common in case of pelvic fracture while PD was common in the lesions below the hip joint. Younger person, responsiveness of sensory nerve conduction and fracture were the factors of better improvement while pattern of involvement (TD/PD) was not. CONCLUSION: The sciatic nerve injuries affected the peroneal division greater than the tibial division, but in case of pelvic fracture it affected the tibial division greater than the peroneal division. The relative fixation and anatomical difference of peroneal nerve was thought to be the cause of those differences.

A Case of Localized Cutaneous Leishmaniasis in A Native Korean / 대한피부과학회지

Localized cutaneous leishmaniasis is a chronic ulcerative, usually self-limiting skin disease, and one of the major tropical diseases. This disease is caused by an infection of genus Leishmania, transmitted by a sandfly, and there are some cases of cutaneous leishmaniasis in Koreans after travelling abroad in endemic areas, such as the Middle East and Africa. We report a case of localized cutaneous leishmania in a 70-year-old native Korean man without history of a trip abroad.

Cystic Periventricular Leukomalacia in the Neonate: Analysis of Sequential Sonographic Findings and Neurologic Outcomes

PURPOSE: To analyse the sequential sonographic findings of cystic PVL and to evaluate relationship between sonographic grading of PVL and patterns of neurologic outcomes. MATERIALS AND METHODS: Authors have retrospectively analysed the sequential sonographic findings of 36 cases of PVL in the preterm neonates. Initial sonographic features done within 3 days of life were divided into 3 patterns such as normal, localized, and diffuse hyperechogenic flare. Grading of PVL confirmed by follow-up studies was classified as involvement of one lobe (grade 1), two lobes (grade 2) and more than extent of grade 2(grade 3). The relationship between sonographic grading of leukomalacia and later neurologic outcomes were also analysed. RESULTS: Initial sonographic patterns according to grading of PVL were normal pattern in seven of nine (77.8%) of grade 1, diffuse hyperechogenic flares in five of eight cases of grade 2 and in 13 of 16 cases of grade 3. There was a significant difference bewteen the grades and frequency of pattern of diffuse hyperechoic flare (p=0.021). Average detection timing of cystic PVL was 38.4+/-18.9 days in grade 1, 29.8+/-14 days in grade 2, and 19.1+/-5.6 days in grade 3 with a significant statistical difference between the detection time and grades (p=0.037). Cerebral palsy has occurred in 62.5% of grade 1 and 100% of grade 2 and grade 3 (p=0.043). Frequency of spastic quadriplegia was higher in grade 3 (76.5%) than in grade 1 (25%) and grade 2 (12.5%) (p=0.001). CONCLUSION: Most of grade 1 cystic PVL revealed normal pattern of white matter echogenicity in initial ultrasonography and needed follow up examination over one month period. Spastic quadriplegia occured mainly in patients with grade 3 cystic PVL.

Two Cases of Pilonidal Sinus / 대한피부과학회지

Pilonidal sinus is a chronic inflammatory disease that is associated with hair; a midline hairy patch or pit in the sacral region with a sinus orifice in the bottom, or a cyst beneath it, in which hair is growing. Also, it is considered to belong in the category of follicular occlusion tetrad. It sometimes becomes inflamed, resulting in a subcutaneous abscess with recurrent infection. It becomes symptomatic during adolescence and presents as a foreign body abscess, with hair as the offender. Histological findings show follicular hyperkeratosis of the infundibulum with plugging and dilatation of follicle. Infiltration of hair occurs in one half of the specimens. Also, inflammatory cells are gathering to meet the challenge. The recommended treatment has been surgical excision of the lesion.