Counting of fetal caudal vertebral body ossification center below terminal conus medullaris in the screening of the closed spine bifida and tethered cord syndrome / 中华超声影像学杂志

Objective:To assess the significance of counting the number of caudal vertebral ossification centers (OCN) below fetal terminal conus medullaris in the screening for closed spina bifida and tethered cord syndrome (TCS).Methods:The OCN was counted in 961 normal fetuses(normal group) between 17 and 41 gestational weeks and in 140 fetuses with closed spina bifida or tethered cord syndrome(abnormal group) from Jan.2013 to Dec.2020 in Affiliated Shenzhen Maternity & Child Healthcare Hospital, Southern Medical University, Women and Children′s Hospital, School of Medicine, Xiamen University and Maternity and Child Health Care of Guangxi Zhuang Autonomous Region. The OCN was counted in the dorsal mid-sagittal section of fetal caudal spine.The reliability and agreement test were evaluated by intraclass correlation coefficients in another 50 normal fetuses. The OCN was compared between two groups. ROC curve and the cut-off value were constructed and calculated.Results:In normal group, the N increased with the growing of gestational age.In the subgroup of 17-20 weeks, the OCN ranged from 5 to 7 in most fetuses. In the others subgroups, the OCN was equal to or greater than 6 in 99.9% cases and more than 6 in 97.1% cases. In abnormal group, OCN was less than 7 in 93.0% fetuses and less than 6 in 82.8% cases. There were statistical differences between the two groups except for the subgroup of 17-20 gestational weeks( P<0.05). With the cut-off value of 6.5, the specificity and sensitivity were 93.0% and 94.3% respectively for predicting the presence of closed spinal dysraphism or TCS. Conclusions:OCN is a simple way to evaluate the position of conus medullaris and to screen for the skin-covered spine dysraphism or TSC. OCN is more than 6 in most normal fetuses. Further evaluation of spine is required in fetuses with N less than or equal to 6.

Clinical analysis of 56 cases with surgical operation of congenital tumor in conus medullaris position / 中国医师杂志

Objective@#To analyze the curative effect of 56 cases with surgical operation of congenital tumor in conus medullaris position, to provide valuable reference information for the surgical operation of congenital tumor in conus medullaris position.@*Methods@#The cases were from 56 patients with congenital tumors in conus medullaris position in Xinjiang Uygur municipal people's hospital from January 2015 to February 2018. According to the classifications of congenital tumors in the conus medullaris position, surgical operation was performed on patients. The curative effect of patients with all kinds of congenital tumors in the conus medullaris position was analyzed and summarized.@*Results@#After 9 months of the follow-up: ⑴ There were totally 18 cases of epidermoid cysts, 16 cases with obvious improvement in lower limb numbness and lower limb motor function, 13 cases with the pain degree effectively relieved and 3 cases without significant improvement in early defecation function. ⑵ There were 15 cases of teratomas, 13 cases without significant improvement in lower extremity numbness, 2 cases with reduced lower extremity numbness, 3 cases with reduced urination and defecation function disturbance and 1 case not recovered. There was no recurrence of tumor. ⑶ There were 8 lipoma patients who were cured and discharged without urination and defecation function disturbance. Life was basically self-sustaining. ⑷ There were 9 cases of hemangioblastoma with significant improvement in spinal cord function, 5 cases without postoperative pain symptoms and 1 case with significant improvement in pain degree. ⑸ There were 6 cases of ependymoma, 2 cases with significant reduction on limb numbness symptoms, 1 case with urinary retention after surgery. There was no significant change in muscle strength of the 2 cases before and after surgery.@*Conclusions@#The clinical effect of surgical operation of congenital tumor in conus medullaris position is clear. Combined with imaging examination and attention to surgical precautions, the surgical treatment effect of congenital tumors in the conus region of the spinal cord can be effectively improved.

Clinical analysis of 56 cases with surgical operation of congenital tumor in conus medullaris position / 中国医师杂志

Objective To analyze the curative effect of 56 cases with surgical operation of congenital tumor in conus medullaris position,to provide valuable reference information for the surgical operation of congenital tumor in conus medullaris position.Methods The cases were from 56 patients with congenital tumors in conus medullaris position in Xinjiang Uygur municipal people's hospital from January 2015 to February 2018.According to the classifications of congenital tumors in the conus medullaris position,surgical operation was performed on patients.The curative effect of patients with all kinds of congenital tumors in the conus medullaris position was analyzed and summarized.Results After 9 months of the follow-up:(1) There were totally 18 cases of epidermoid cysts,16 cases with obvious improvement in lower limb numbness and lower limb motor function,13 cases with the pain degree effectively relieved and 3 cases without significant improvement in early defecation function.(2) There were 15 cases of teratomas,13 cases without significant improvement in lower extremity numbness,2 cases with reduced lower extremity numbness,3 cases with reduced urination and defecation function disturbance and 1 case not recovered.There was no recurrence of tumor.(3) There were 8 lipoma patients who were cured and discharged without urination and defecation function disturbance.Life was basically self-sustaining.(4) There were 9 cases of hemangioblastoma with significant improvement in spinal cord function,5 cases without postoperative pain symptoms and 1 case with significant improvement in pain degree.(5) There were 6 cases of ependymoma,2 cases with significant reduction on limb numbness symptoms,1 case with urinary retention after surgery.There was no significant change in muscle strength of the 2 cases before and after surgery.Conclusions The clinical effect of surgical operation of congenital tumor in conus medullaris position is clear.Combined with imaging examination and attention to surgical precautions,the surgical treatment effect of congenital tumors in the conus region of the spinal cord can be effectively improved.

Influence of age, sex, height and lumber stenosis on the position of the conus medullaris in adults / Influencia de la edad, sexo, altura y estenosis lumbar en la posición del cono medular en adultos

Anatomical orientation of the termination level of Conus Medullaris (CM) has imperative role clinically for anesthetists and neurosurgeons which is considered as an objective guide to perform spinal anesthesia and spinal punctures circumspectly with less chance to have serious injuries. The current retrospective study was carried on to determine the location of the CM and how its termination level can be influenced by age, sex, height and lumber stenosis spine disease. The study included 462 participants that consisted of 199 men and 263 women range from 21 to 80 years of age and height range between 150-190 cm. Also, it included 150 lumber stenosis patients. The location of the CM was imaged using a series of magnetic resonance images (MRI) for the lumbosacral spine at different levels including, T12, T12-L1, L1, L1-L2, and L2. The measurements revealed inconsiderable differences in the CM termination level in relation to age, sex and height in a healthy study population. Moreover, the results showed insignificant differences in the CM termination level between men and women whether they are healthy or having lumbar spinal stenosis. In conclusion, the most common level of CM termination is at L1 followed by L1-L2. It is safe to perform a lumbar neuraxial procedures at the level of L3-L4.

La orientación anatómica del nivel de terminación del Conus medullaris (CM) tiene un importante papel clínico para los anestesistas y neurocirujanos, que se considera una guía objetiva para realizar la anestesia espinal y las punciones de la columna circunspectivamente con menos posibilidades de provocar lesiones graves. Se llevó a cabo un estudio retrospectivo para determinar la ubicación del CM y cómo su nivel de terminación puede verse afectado por la edad, el sexo, la altura y una patología de la columna vertebral, la estenosis lumbar. El estudio incluyó 462 participantes que consistían en 199 hombres y 263 mujeres de 21 a 80 años de edad y una altura de entre 150-190 cm. Además, se incluyeron 150 pacientes con estenosis lumbar. La ubicación del CM se determinó mediante una serie de imágenes de resonancia magnética (RM) de la columna lumbosacra a diferentes niveles, incluidos T12, T12-L1, L1, L1-L2 y L2. Las mediciones revelaron diferencias considerables en el nivel de terminación de CM en relación con la edad, el sexo o la altura en una población de estudio saludable. Además, los resultados mostraron diferencias poco significativas en el nivel de terminación de CM entre hombres y mujeres, sanos o con estenosis espinal lumbar. En conclusión, se encontró que el nivel más común de terminación del CM es L1 seguido de L1-L2, considerándose seguro realizar procedimientos neuroaxiales lumbares a nivel de L3-L4.

Magnetic Resonance Imaging Observations of the Conus Medullaris in a Korean Population

STUDY DESIGN: Retrospective study (level of evidence: level 3). PURPOSE: To study the anatomy of the conus medullaris in Koreans. OVERVIEW OF LITERATURE: The anatomical position of the conus medullaris is well-documented in anatomy textbooks; however, the shape of the conus in the canal rarely described. Furthermore, to our knowledge, no study in Korea has not yet assessed the shape of the conus as well as its position in the canal via cadavaric dissection and/or magnetic resonance imaging (MRI). METHODS: MRI findings of 189 Korean patients aged 2–94 years (93 men and 94 women) were assessed. No subjects from other ethnicities were included. The method proposed by Arai and colleagues was used to assess the termination point and shape of the conus in the canal. The position of the intervertebral disc trisection of the vertebral body closest to the tip of the conus was recorded at the canal level. RESULTS: The tip of the conus medullaris was positioned from the upper T12 body to the L2–L3 disc, mostly in L1 bodies (52.4%), followed by the L2 bodies (22.5%), the L1–L2 disc, and the L2–L3 disc (1.1%). The shape of the conus was classified as type A in 74 (39.6%), type B in 58 (31%), and type C in 55 patients (29.4%). The conus did not terminate at the L3 body in any patient. In the first decade ones (five children) conus positioned rather lowly from L1 bodies to L2–L3 disc, and no type A conus shape, and mostly type B (80%). CONCLUSIONS: The conus medullaris was positioned mostly in the lower one-third of L1 and it in the first decades terminated lowly. No type A in the first decade one, and type B was mostly frequently formed which was followed by type C.

The new approach in the location of the fetal conus medullaris and its application in tethered cord syndrome / 中华超声影像学杂志

Objective To evaluate the position of the fetal conus medullaris during pregnancy and its value in detecting tethered cord syndrome(TCS). Methods Nine hundred and seventy-four normal fetuses and 46 fetuses with TCS between 15 and 41 weeks gestation were involved in the study.Parameters D 1 (the distance between the end of the conus medullaris and the caudal edge of last vertebral body ossification center) and D2 (the distance from the end of the conus medullaris to the caudal skin namely the intersection point of the extending line of D1 and the skin) were measured in the caudal midsagittal plane of the spine. Sixty normal fetuses were chosed randomly for interobserver variability.Correlation analysis between these two parameters and gestational age(GA) were conducted and the normal reference value of these parameters were calculated in normal group. The ratios of growth parameters ( Biparietal diameter, Head circumference,Abdominal circumference,Femur length) to D1 and D2 were calculated separately to observe the difference of the ratios between two groups. All the parameters and ratios of normal fetuses were compared with that of TCS cases.Results There was no significant difference in D1 and D2 between two observers.A significant linear correlation between the parameters and GA was found in normal group,linear regression equations were D1=0.251 GA -2.265 cm (R2=0.926,P <0.01) and D2=0.267 GA -1.812 cm(R2=0.928,P <0.01),respectively.D1 and D2 were much lower in normal group than in abnormal group (all P <0.01). The ratios of the growth parameters to D1 and D2 were relatively stable and had statistically differences between two groups in different gestational age. Conclusions The methods that determination of D1 and D2 are simple and feasible,and could help to the prenatal diagnosis of TCS.

Study of recognition of atlanto-axial intervertebral space for the localization of fetal vertebrae with three-dimensional ultrasound / 中华超声影像学杂志

Objective To study the feasibility of visualization of atlanto-axial intervertebral space for the localization of fetal centrums with three-dimensional ultrasound and to explore the relationship of intervertebral space with gestational weeks. Methods A total of 223 cases of normal single pregnancy in the second trimester were enrolled in the study to acquire the 3D volume of fetal spines. The distances between the transverse processes of cervical vertebra were measured in vertical horizontal line.The distance between the first and second cervical vertebra was labeled C1,and then labelled C2,C3,C4,C5 and C6 as follows.Results The successful rate of 3D acquisition of 206 cases was 92.4%.The distance between ICC values of C1 -C6 were 0.985,0.984,0.971,0.956,0.978,0.923,respectively and the consistency data measuring was well.The atlanto-axial intervertebral space was significantly larger than other intervertebral space ( P =0.012) and the mean ratios of C1 to C2 -C6 were 1.41,1.39,1.37,1.40,1.39,respectively, which had no correlation with gestational ages ( P = 0.877,0.915,0.838,0.859,0.908,respectively). Conclusions Visualization of the atlanto-axial intervertebral space with three-dimensional ultrasound is a direct and simple method without any consumption,which can help to quickly locate the axial vertebra and other vertebras and conus medullaris.

Conus Medullaris Levels on Ultrasonography in Term Newborns : Normal Levels and Dermatological Findings

OBJECTIVE: Ultrasonography (US) is the most non-invasive, safe, and, especially in the period of infancy, best method for visualizing and examining the spinal cord. Furthermore, US is the primary work-up for development of the spinal canal, and for follow-up on issues relating to subcutaneous tissues, bone development, and the spinal cord. Conus medullaris terminates at the second lumbar vertebra, according to a consensus in the literature.METHODS: Healthy children under the age of 6 months who were admitted to the radiology clinic for routine USG follow-ups between the dates of March 2012 to December 2014 were included in this study.RESULTS: Our study includes data from 1125 lumbosacral ultrasounds. The terminal point of the conus level of the attended infants, superior, middle part, inferior of the vertebrae L1, L2, and L3. Furthermore, the termination of the discal distance ratio did not differ significantly between genders.CONCLUSION: Therefore, according to our results, gender is not an influencing factor in the termination of the spinal cord. Based on the study we performed, as well as the previous literature, in infants without a recognized spinal pathology, the spinal cord is detected below the vertebra L3.

Conus Medullaris Levels on Ultrasonography in Term Newborns : Normal Levels and Dermatological Findings

OBJECTIVE: Ultrasonography (US) is the most non-invasive, safe, and, especially in the period of infancy, best method for visualizing and examining the spinal cord. Furthermore, US is the primary work-up for development of the spinal canal, and for follow-up on issues relating to subcutaneous tissues, bone development, and the spinal cord. Conus medullaris terminates at the second lumbar vertebra, according to a consensus in the literature. METHODS: Healthy children under the age of 6 months who were admitted to the radiology clinic for routine USG follow-ups between the dates of March 2012 to December 2014 were included in this study. RESULTS: Our study includes data from 1125 lumbosacral ultrasounds. The terminal point of the conus level of the attended infants, superior, middle part, inferior of the vertebrae L1, L2, and L3. Furthermore, the termination of the discal distance ratio did not differ significantly between genders. CONCLUSION: Therefore, according to our results, gender is not an influencing factor in the termination of the spinal cord. Based on the study we performed, as well as the previous literature, in infants without a recognized spinal pathology, the spinal cord is detected below the vertebra L3.

Conus Medullaris Syndrome Due to Posterior Spinal Artery Infarction

A 77-year-old female with a history of osteoarthritis visited our clinic complaining of lower back pain, paresthesia in both legs, and voiding difficulty. Her pain and temperature sensations were diminished below the L1 dermatome, and proprioception was decreased in both feet. The findings of a routine laboratory workup, echocardiogram, and cerebrospinal fluid studies were normal. Spine magnetic resonance imaging revealed high T2-weighted signal intensities and diffusion restriction in the posterior conus medullaris. The patient was diagnosed and treated for posterior spinal artery infarction.

Three-dimensional ultrasound volume contrast imaging and tomography ultrasound imaging techniques in observing fetal tethered cord / 中国医学影像技术

Objective To evaluate the value of three-dimensional ultrasound volume contrast imaging (VCI) and tomo graphy ultrasound imaging (TUI) techniques in observing fetal spinal conus medullaris (CM) position and lumbar enlargement of spinal cord morphologic changes,for assessment of tethered cord (TC).Methods Totally 17 abnormal fetuses of spinal diseases combined with TC (abnormal group) were examined by three dimensional ultrasound VCI and TUI techniques.The position of CM was recorded,and the transverse and anteroposterior diameters of lumbar enlargement of spinal cord were measured and compared with 300 cases of normal fetuses (normal group).Results As the growth of the gestational age (CA),CM terminal position increased.All the ends of CM located at L3 or L3 above level in normal.The transverse and anteroposterior diameters of lumbar enlargement in normal group showed good linear relationship with GA.Transverse diameter (mm) =0.677+0.147 ×GA (R2 =0.836,P＜0.05),anteroposterior diameter (mm)-0.994+ 0.152× GA (R2=0.894,P＜0.05).Compared with the corresponding GA fetuses in normal group,the anteroposterior diameter of lumbar enlargement decreased in abnormal group (P=0.002),while no statistical difference of the transverse diameter was found between the two groups (P=0.082).Conclusion Position of CM and lumbar enlargement measure ment can provide valuable reference information for clinical prenatal diagnosis of fetal spinal TC.

Experimental study of insulin receptor change from bladder after conus medullaris injury in rats / 中华显微外科杂志

Objective To observe the change rules of insulin receptor from rat bladders after losing lower cen-tal innervations so as to explore the function of insulin receptor in denervated bladder. Methods From January, 2016 to June, 2017, 40 Sprague-Dawley rats were randomly divided into experimental group and control group,each group was 20. The conus medullaris of rats in experimental group were damaged, and rats in control group received sham opera-tion. The rats in 2 groups were sacrificed at different time after surgery (1 day, 1 week, 1 month, 3 months). Bladder specimens were harvested to perform wet weight measurement and immunohistochemical detection of insulin receptor. Results Corresponding to 1 day, 1 week, 1 month and 3 months after surgery, the bladder wet weight of control group were (0.089±0.022)g, (0.094±0.038)g, (0.106±0.112)g and(0.102±0.048)g, and of experimental group were (0.092± 0.026)g, (0.110 ±0.034)g, (0.538 ±0.098)g and (1.528 ±0.462)g. One month and 3 months after surgery, bladder wet weight of experiment group were significantly increased as compared with those of control group (P<0.05). One day, 1 week, 1 month and 3 months after the operation, the positive rate of insulin receptor expression was 60％, 100％, 100％and 80％. And strongly positive rate was 55％. In control group, the positive rate of insulin receptor expression was 20％, 40％, 40％, and 0％. The expression of insulin receptor in experimental group was significantly higher than that in con-trol group in every stage(P<0.05). Conclusion The expression of insulin receptor is significantly increased after den-ervation of bladder. The defections of insulin receptor might lead to apoptosis and muscle wasting after denervation. Re-store insulin receptor function might be key point to prevent bladder tissue from irreversible damage.

Three-dimensional volume contrast imaging in location of fetal conus medullaris level / 中国介入影像与治疗学

Objective To evaluate the repeatability for location of the level of fetal conus medullaris (CM) with three-dimensional volume contrast imaging (3D-VCI).Methods Totally 164 normal fetuses and 12 fetuses with low-lying CM were enrolled.The location of fetal CM was performed sonographically using 3D-VCI,and the inter-and intra-observer agreement was assessed.Results The Kappa value of inter-and intra-observer agreement in evaluation on normal fetues CM was 0.943 and 0.915,and that for abnormal fetues CM was 0.965 and 0.913,respectively.Conclusion Inter-and intra-observer agreement of 3I-VCI in location of level of fetal CM is high.The acquired images are clear and intuitive,which is manipulated simply and conveniently.This method can be used for rapid evaluation of the level of fetal CM.

Three-dimensional volume contrast imaging in location of fetal conus medullaris level / 中国介入影像与治疗学

Objective To evaluate the repeatability for location of the level of fetal conus medullaris (CM) with three-dimensional volume contrast imaging (3D-VCI).Methods Totally 164 normal fetuses and 12 fetuses with low-lying CM were enrolled.The location of fetal CM was performed sonographically using 3D-VCI,and the inter-and intra-observer agreement was assessed.Results The Kappa value of inter-and intra-observer agreement in evaluation on normal fetues CM was 0.943 and 0.915,and that for abnormal fetues CM was 0.965 and 0.913,respectively.Conclusion Inter-and intra-observer agreement of 3I-VCI in location of level of fetal CM is high.The acquired images are clear and intuitive,which is manipulated simply and conveniently.This method can be used for rapid evaluation of the level of fetal CM.

Conus medullaris position in an adult population: analysis of magnetic resonance imaging / Posición del cono medular en una población adulta: análisis con imágenes de resonancia magnética

The objective of this study was to evaluate the variation in position of the conus medullaris (CM) in male and female patients without spinal deformity, to correlate the termination level in magnetic resonance (MR) images of the lumbar spine. 921 patients consisted of 607 men and 314 women were evaluated by MRI. The strength of T1 weighted MRI device was 1.5 Tesla. The patients were in supine position when measured. The termination level of the conus medullaris was recorded in relation to the upper, middle or lower third of the adjacent vertebra and the adjacent intervertebral disc. The patients in our study group were examined for low back pain. The members with spinal deformity were excluded. The distribution of conus medullaris localization was measured to range from T12 to L2-L3. There was a statistically significant difference in the mean conus medullaris position related to gender also a significant difference between increasing age and conus position in female patients. These findings suggest that the distribution of CM location in a large adult population was shown to range from the upper third of T12 to the lower third of L2-L3 disc space both in women and men.

El objetivo de este estudio consistió en evaluar la variación en la posición del cono medular (CM) en pacientes masculinos y femeninos sin deformidad espinal, para correlacionar el nivel de terminación en imágenes de resonancia magnética (RM) de la columna lumbar. Fueron evaluados por RM un total de 921 pacientes, 607 hombres y 314 mujeres. La fuerza ponderada del dispositivo de RM en T1 fue 1,5 Tesla. Los pacientes se ubicaron en posición supina al momento de la medición. El nivel de terminación del cono medular se registró en relación con el tercio superior, medio o inferior de la vértebra adyacente y el disco intervertebral adyacente. Los pacientes de nuestro grupo de estudio fueron examinados por dolor lumbar. Se excluyeron los individuos con deformidad espinal. La distribución de la localización del cono medular se midió, con variaciones entre T12 a L2-L3. Hubo una diferencia estadísticamente significativa en la posición media del cono medular relacionada con el sexo y también una diferencia significativa entre el aumento de la edad y la posición del cono medular en las mujeres. Estos hallazgos sugieren que la distribución de la ubicación del CM en una población adulta se encontró en un rango que se extendió desde el tercio superior de T12 al tercio inferior del espacio discal L2-L3, tanto en mujeres como en hombres.

Morphometric Analysis of Distances between Sacral Hiatus and Conus Medullaris Using Magnetic Resonance Image in Korean Adult / 체질인류학회지

The purpose of this study was to provide basic biometric data on Korean adults through magnetic resonance imaging (MRI)-based measurements of the distances between the apex of sacral hiatus (SH) and the termination of dural sac (DS), and between SH and conus medullaris (CM) because they are critical to the performance of epidural neuroplasty. A total of 200 patients (88 males and 112 females) with back pain, who had no spine fracture, significant spinal deformity, and spondyloisthesis were selected for this study. The subjects were of mean age 54.3 (20~84) years and mean height 161.3 cm (135~187). T2-weighted MRI images were used for correlation analysis to evaluate the relationships between the distances, and variables such as sex and height. In all patients, the mean distance between SH and DS was 62.8±9.4 mm and the mean distance between SH and CM was 232.2±21.8 mm. The minimum distance and the maximum distance between SH and DS were 34.8 mm and 93.9 mm respectively, and the minimum distance and the maximum distance between SH and CM were 155.0 mm and 284.0 mm respectively. In female patients, both the distances between the SH and DS, and between SH and CM were shorter when compared to those of the male patients (p<0.05). Both the distances between SH and DS and between SH and CM showed a significant correlation with height (p<0.01). The results of this study will provide a useful biometric data on the distances between SH and DS and between SH and CM in Korean in ensuring clinical safety and in the development of more effective catheterization techniques for epidural neuroplasty in Korean.

Conus Medullaris Syndrome Caused by Delayed Recollapse after Surgery of Burst Fracture: A Case Report

STUDY DESIGN: A case report. OBJECTIVES: Lumbar burst fracture was treated with operation, which delayed recollapse of L1 and led to conus medullaris syndrome. SUMMARY OF LITERATURE REVIEW: After operation, conus medullaris syndrome causing by delayed recollapse is not frequently reported. MATERIALS AND METHODS: A 56-year-old male was admitted with lower back pain caused by a fall. Radiologic findings showed L1 burst fracture with about 42% of height loss. There was no neurologic deficit. Posterior fusion was performed using instrumentation. Five weeks after the operation, the patient was admitted for urination and defecation difficulty. Radiologic findings showed that the L1 had recollapsed with about 38% of height loss. To resolve the problem, anterior surgery was performed. RESULTS: Two years after surgery, bladder and anal sphincter dysfunction wasn't recovered. CONCLUSIONS: Lumbar burst fracture should be follow up carefully until union of the fracture because burst fracture leads to delayed recollapse.

Sequestrated Intradural Disc Herniation Around Couns Medullaris: A Case Report

STUDY DESIGN: A case report. OBJECTIVES: To report a rare case of intradural disc herniation (IDH) around conus medullaris. SUMMARY OF LITERATURE REVIEW: IDH is rare with an incidence of less than 1% of all lumbar disc herniations. It is important to differentiate IDH from other condition with accurate diagnosis and subsequent surgical treatment. IDH has a higher risk of neurologic deficit, like conus medullaris syndrome and cauda equina syndrome. MATERIALS AND METHODS: A 62 year-old male was affected by lumbar back pain radiating to the anterolateral aspect of the right thigh for 5 days. MRI showed a mass that existed on the anterior portion of the conus medullaris. We performed partial laminectomy at the L1-L2level. The mass located anteriorly in the intradural space was eliminated after durotomy by a posterior approach. RESULTS: We confirmed the IDH for histopathology. CONCLUSIONS: IDH usually needs accurate differential diagnosis. Preoperative MRI scans are necessary to differentiate IDH from other intradural lesions. The confirmative diagnosis can be done only in the operative field.

Intramedullary Spinal Lesions Involving the Conus Medullaris: MR Imaging Features for Differential Diagnosis

PURPOSE: Intramedullary spinal lesions in the conus medullaris (CM), including tumors and vascular lesion, are rarely reported. We reported various MR features of intramedullary spinal cord lesions involving the CM including ependymoma, hemangioblastomas, dermoid cyst, ventriculus terminalis and spinal AVF and tried to discuss them for differential diagnosis. MATERIALS AND METHODS: Six patients (male: female = 4:2, mean age = 44.3 year old) were enrolled from the clinical database of our institute from 2004 to 2010 and their radiological images and clinical symptoms were reviewed retrospectively. All patients had taken initial and postoperative MRI with contrast enhancement using gadopentate dimeglumine (Gd-DTPA). These images were analyzed by tumor size, location, signal intensity relative to the spinal cord, vascular flow voids, syrinx or cyst, edema and enhancement pattern. RESULTS: Contrast enhancement was seen in all intramedullary masses. An eccentric enhancing nodule was noted in two hemangioblastomas and unusual peripheral rim enhancement with septation was seen in ventriculus terminalis. Patchy enhancement of the CM was observed in spinal arteriovenous fistula (AVF). Extensive cord edema adjacent to the intramedullary lesions was seen in four cases and syrinx was noted in three cases. Vascular signal voids were found in two hemangioblastomas and one spinal AVF. CONCLUSION: In evaluation of intramedullary spinal lesions in the CM, it is necessary to consider these unusual MR findings and discriminate various pathologies with prudence and caution.

Caring about medullary anesthesia in Saimiri sciureus: the conus medullaris topography

Saimiri sciureus is a New World non-human primate (NHP) that inhabits Brazilian rain forests. Surgical interventions in wild NHPs can be considered common both for experimental studies procedures and corrective procedures for endangered species. Among various anesthetic procedures, the epidural anesthesia or blockades, depending on the surgical procedure, might be considered elective for wild monkeys, mostly based on its safeness, efficiency and non-time consuming characteristics. However its safeness would be limiting because of the spinal cord arrangement. Notwithstanding the available former studies on New World NHP anatomy, the description of the medullar cone of Saimiri sciureus is still scarce. Therefore, we believe that the better understanding the medullar cone of Saimiri sciureus would contribute to improve the applicability of epidural procedures in the species. Vertebrae architecture of Saimiri sciureus was composed by 9 lumbar, 3 sacral and 18 coccygeal vertebrae, and the medullar cone measured about 3.3 cm. We can conclude that the conus medullaris in Saimiri sciureus is situated more caudally in comparison to other species.

Saimiri sciureus é um primata não humano do novo mundo (NHP) que habita as florestas úmidas brasileiras. Intervenções cirúrgicas em NHP selvagens podem ser consideradas comuns em estudos experimentais ou procedimentos corretivos para espécies em perigo. Entre os vários procedimentos anestésicos, a anestesia ou bloqueio epidural depende do procedimento cirúrgico a ser realizado, podendo ser considerada eletiva para macacos selvagens baseada na segurança, eficiência e pouco tempo consumido, entretanto sua segurança pode estar limitada devido ao arranjo da medula espinhal. Apesar de existirem estudos anatômicos disponíveis de NHP a descrição do cone medular do Saimiri sciureus permanece escassa. Portanto, nós acreditamos que o melhor entendimento a respeito do cone medular do Saimiri sciureus pode contribuir para melhorar a aplicabilidade de procedimentos epidurais nesta espécie. A arquitetura vertebral do Saimiri sciureus é composta por 9 vértebras lombares, 3 sacrais e 18 coccígeas e o cone medular apresentou tamanho médio de 3,3 cm. Podemos concluir que o cone medular Saimiri sciureus está situado mais caudalmente em comparação com outras espécies.