The role of MR imaging in the diagnosis and treatment of anterior sacral meningocele. Report of two cases

“Spinal Dysraphism Spectrum: A Novel Protocol-based Approach for Accurate Diagnosis on Imaging”

The spectrum of spinal dysraphism includes various congenital anomalies of the spinal column and spinal cord. Clinical manifestations are varied and range from paraparesis, gastrointestinal, genitourinary, and musculoskeletal anomalies to asymptomatic cases depending on the level and extent of spinal involvement. Magnetic resonance imaging is the gold standard for assessing these complex spinal anomalies. Even for the experienced radiologist, diagnosis can be challenging in complex cases. It is essential to be aware of the normal embryological developmental stages of the spine for an adequate understanding of the complex anatomy, pathogenesis, and cliniconeuroradiological classification of spinal dysraphism, which is necessary for accurately diagnosing each case as a particular pathological entity. In this pictorial essay, we have depicted the stages and process of spinal embryogenesis, cliniconeuroradiological classification, and the imaging spectrum of spinal dysraphism. As the confusing terminologies and the numerous variants can potentially lead to misdiagnosis, we have proposed a step-wise protocol-based imaging approach to analyze each case and arrive at the correct diagnosis systematically. This would be particularly helpful in confusing and difficult cases, as accurate and early diagnosis is crucial for appropriate patient management.

MRI of Tumors and Tumor Mimics in the Female Pelvis: Anatomic Pelvic Space-based Approach

Pelvic masses can present a diagnostic challenge owing to the difficulty in assessing their origin and the overlap in imaging features. The majority of pelvic tumors arise from gastrointestinal or genitourinary organs, with less common sites of origin including the connective tissues, nerves, and lymphovascular structures. Lesion evaluation usually starts with clinical assessment followed by imaging, or the lesion may be an incidental finding at imaging performed for other clinical indications. Since accurate diagnosis is essential for optimal management, imaging is useful for suggesting the correct diagnosis or narrowing the differential possibilities and distinguishing tumors from their mimics. Some masses may require histologic confirmation of the diagnosis with biopsy and/or up-front surgical resection. In this case, imaging is essential for presurgical planning to assess mass size and location, evaluate the relationship to adjacent pelvic structures, and narrow differential possibilities. Pelvic US is often the first imaging modality performed in women with pelvic symptoms. While US is often useful to detect a pelvic mass, it has significant limitations in assessing masses located deep in the pelvis or near gas-filled organs. CT also has limited value in the pelvis owing to its inferior soft-tissue contrast. MRI is frequently the optimal imaging modality, as it offers both multiplanar capability and excellent soft-tissue contrast. This article highlights the normal anatomy of the pelvic spaces in the female pelvis and focuses on MRI features of common tumors and tumor mimics that arise in these spaces. It provides an interpretative algorithm for approaching an unknown pelvic lesion at MRI. It also discusses surgical management, emphasizing the value of MRI as a road map to surgery and highlighting anatomic locations where surgical resection may present a challenge. ^©RSNA, 2019.

Rectothecal fistula complicating anterior sacral meningocele repair

We present a case of an iatrogenic rectothecal fistula in a 34-year-old man who underwent repair of a congenital anterior sacral meningocele, intraoperatively complicated by rectal perforation. Postoperatively, the patient developed symptoms of meningitis prompting concern for the cerebrospinal fluid leak. Subsequent workup with computed tomography (CT) and magnetic resonance imaging demonstrated a postoperative pseudomeningocele and fistulization with an abdominal fluid collection. CT myelography confirmed the fistulous connection was between the pseudomeningocele and the rectum. Clinical suspicion of a rectothecal communication should be elevated for patients who undergo anterior sacral meningocele repair and postoperatively develop symptoms concerning for meningitis. We suggest that CT myelography be considered in the evaluation of viscero-thecal fistulas if clinical or other initial radiologic evaluation suggests the possibility of this diagnosis.

Closure of a giant anterior sacral meningocele with an omental flap in a patient with Marfan syndrome: case report

Anterior sacral meningoceles (ASMs) are rare lesions often associated with connective tissue disorders. These lesions are typically treated posteriorly via closure of the dural stalk. However, given their insidious nature, ASMs can be quite large on presentation, and this approach may not provide adequate decompression. In this case report, the authors describe the successful treatment of a large ASM through drainage and watertight closure of the cyst with an omental flap. A 43-year-old woman with a history of Marfan syndrome and a large ASM was referred for neurosurgical intervention. The ASM was filling the pelvic cavity and causing severe compression of the bladder. The patient underwent surgical decompression of the cyst through an anterior transabdominal approach and closure of the fistulous tract with a pedicled omental flap. This is the first reported case of successful closure of an ASM with an omental flap. At the 6-month follow-up, the ASM had not recurred on imaging and the patient's symptoms had resolved. Anterior sacral meningoceles are rare lesions that often require neurosurgical intervention. Although most can be treated posteriorly, large ASMs compressing the abdominal or pelvic organs may require a transabdominal approach. Moreover, ASMs with wide dural stalks may benefit from closure with an omental flap.

Anterior sacral meningocele presenting as intracystic bleeding

PURPOSE

To report a case of anterior sacral meningocele with intralesional bleeding secondary to sacrococcygeal trauma. Likewise, there is a discussion about the physiopathology and the surgical approach to these types of lesions.

METHODS

A 43-year-old man diagnosed with Marfan syndrome suffered sacrococcygeal trauma. He was admitted to the emergency room due to symptoms of headache, nausea, and lower limb subjective weakness. CT and MRI showed a large retroperitoneal mass with hemorrhagic content close to the sacrum. Likewise, the MRI showed an image compatible with subarachnoid hemorrhage in the thoracic spinal area, cerebral convexity, and the basal cisterns. The patient went into surgery for an anterior abdominal approach in the midline to reduce the content of the lesion, and subsequently, in the same act, a posterior approach was done with an S1-S2 laminectomy and obliteration of the pedicle. Postoperative MRI 5 months later showed resolution of the ASM.

RESULTS

Anterior sacral meningocele is characterized by herniation of the dura mater and the arachnoid mater outside the spinal canal through a defect of the sacrum. We add the risk of bleeding after trauma-never seen in the literature-as one of the possible inherent complications of this lesion.

CONCLUSIONS

This report highlights a complication never seen in the literature of a relatively rare condition. In our case, the combined approach was effective for both clinical control and lesion regression.

Imaging spectrum of spinal dysraphism on magnetic resonance: A pictorial review

Congenital malformations of spine and spinal cord are collectively termed as spinal dysraphism. It includes a heterogeneous group of anomalies which result from faulty closure of midline structures during development. Magnetic resonance imaging (MRI) is now considered the imaging modality of choice for diagnosing these conditions. The purpose of this article is to review the normal development of spinal cord and spine and reviewing the MRI features of spinal dysraphism. Although imaging of spinal dysraphism is complicated, a systematic approach and correlation between neuro-radiological, clinical and developmental data helps in making the correct diagnosis.

Variants of Currarino Syndrome: Embryological Association and Review of Pertinent Literature

Currarino syndrome is a triad of sacral defect, anorectal malformation and a presacral mass. The diagnosis is usually made late in childhood and about 50% of cases are familial with autosomal dominant inheritance. We present two neonates (one with vestibular fistula, and another with cloacal malformation) with the features consistent with Currarino syndrome, but with Altman’s type II sacrococcygeal teratoma, that is, presacral mass having an external sacrococcygeal component also. We believe that this triad should be considered a variant of Currarino syndrome. In first case, excision of the mass along with coccyx, followed by primary Posterior Sagittal AnoRectoPlasty was performed in the same setting. The patient succumbed to death due to septicemia as a result of wound sepsis. Learning from the previous experience, we decided to do a diverting sigmoid loop colostomy followed by posterior sagittal excision of the mass along with coccyx, in same sitting in the second case. There was no recurrence. Though HLXB9 has been identified as the major causative gene in Currarino syndrome, exact pathogenesis is still unclear. We herein highlight the significance of this variant of Currarino syndrome and propose a theory on the basis of an embryological association between the malformation complex.

Imaging of congenital spine and spinal cord malformations

This article reviews normal embryologic development of the spine and spinal cord and the imaging features of congenital abnormalities of the spine and spinal cord, with particular focus on magnetic resonance imaging. The authors discuss spinal dysraphisms, a heterogeneous group of congenital abnormalities of the spine and spinal cord, and provide information to expand understanding of these complex entities.

Unusual presentation of an anterior sacral meningocele: magnetic resonance imaging, multidetector computed tomography, and fistulography findings of bacterial meningitis secondary to a rectothecal fistula

An anterior sacral meningocele, a rare congenital anomaly, manifested in a previously healthy 44-year-old woman with findings of meningitis, including headache, vomiting, unconsciousness, and fever. Nontraumatic pneumocephalus, tetraventricular hydrocephalus, fluid-fluid level at the lateral ventricles, and pial enhancement were observed on multidetector computed tomography. A ventricular drainage catheter was placed to decompress the hydrocephalus, and drainage was performed urgently. Escherichia coli was isolated from the drainage material. Whole-spine magnetic resonance imaging and fistulography were undertaken on the third day after admission to evaluate for anal and urinary incontinence and pareses of both upper and lower extremities. Spinal arachnoiditis, tethered cord, dysgenesis of the sacrum, and a rectothecal fistula were demonstrated. Specific antibiotic treatment and surgery for fistula tract excision were performed.

Adult anterior sacral meningoceles misdiagnosed as pelvic cysts

Anterior sacral meningocele (ASM) is a rare condition characterised by the herniation of the meningeal sac anteriorly through a bony defect in the sacrum. In patients without any symptoms, ASM can be difficult to diagnose. We present one case of ASM misdiagnosed as pelvic cysts.

Variable presentations of Currarino syndrome in three members of the same family

The article presents an autosomal dominant Currarino syndrome with incomplete penetrance in three out of four members of the same family. The mother had only a bony sacral defect and no other signs. In the older daughter, the syndrome was completely developed with presacral cystic teratoma, a sacral defect and abdominal discomfort. The younger daughter had no clinical or imaging features of the disease. The only son harboured presacral meningocele, urinary stenosis and a sacral defect. The daughter and son with developed variants of the syndrome were successfully operated on and are now symptom free.

Presacral tumours in adults

Presacral tumours represent a heterogeneous group of predominantly benign and occasionally malignant neoplasms. Due to the rarity of these tumours, their management is often performed in an ad hoc fashion and an algorithm for optimal treatment remains undefined. This review aims to present an overview of presacral tumours, focusing on their presentation, pathology, investigation and management.

Anaerobic meningitis secondary to a rectothecal fistula arising from an anterior sacral meningocele: report of a case and review of the literature

An anterior sacral meningocele is a diverticulum of the thecal sac protruding anteriorly from the sacral spinal canal into the extraperitoneal presacral space. It is a rare congenital anomaly comprising of a thin wall of fibrous connective tissue, and containing cerebrospinal fluid and, occasionally, adjacent nerve fibers. We report an unusual case of a 48-year-old male who presented with meningitis secondary to a rectothecal fistula arising from an anterior sacral meningocele.

Anterior sacral meningocele simulating ovarian cyst

Anterior sacral meningocele is a rare condition characterized by the herniation of meningeal membranes and cerebrospinal fluid through a defect in the anterior aspect of the sacrum. We report a case of an anterior sacral meningocele that was mimicking an ovarian cyst.

Pelvic meningocele can be missed during laparoscopy

Pelvic meningocele is an uncommon condition and is frequently asymptomatic. The diagnosis easily can be mistaken as ovarian cyst on pelvic sonography. In many reported cases, the diagnosis was made during laparotomy for presumed ovarian cysts. Myelography, computerized tomography (CT), or magnetic resonance imaging (MRI) is useful for definitive diagnosis. A 49-year-old woman, who had a normal diagnostic laparoscopy 3 years prior, was referred for a persistent ovarian cyst. Repeat laparoscopy revealed a retroperitoneal cyst in the left pelvic sidewall. Both ovaries and fallopian tubes were normal. Subsequent CT and MRI were used to diagnose pelvic meningocele. We speculate that pelvic meningoceles can be missed during laparoscopy due to the increased intraperitoneal pressure and the potential reduction in the cerebrospinal fluid pressure at the lumbosacral level.

Presacral Meningocele Associated with Hereditary Sacral Agenesis and Treated Surgically: Evaluation in Three Members of the Same Family

OBJECTIVE AND IMPORTANCE:

Presacral meningocele in hereditary sacral agenesis is a complex and unusual spinal dysgenetic syndrome. Recognition of the syndromic triad, its natural history, and familial presentation has important practical applications for the management of this disease as well as its complications.

CLINICAL PRESENTATION:

This report concerns three patients in one family with Currarino syndrome. We detail its clinical presentation, operative management, and outcome and suggest management procedures based on reports in the literature and the results of our surgical techniques, which focus on cases with an “incomplete” triad.

INTERVENTION:

Three members of the same family, one adult and two children, underwent surgery through the posterior sacral approach tying off the communication between dural sac and anterior meningocele. The adult underwent a second surgical procedure in which a custom-designed surgical technique was used to resolve postoperative cerebrospinal fluid leakage. One of the children underwent an additional posterior sagittal anorectoplasty to remove a presacral teratoma.

CONCLUSION:

We report a rare occurrence of three familial cases of sacral agenesis accompanied by a presacral mass with various degrees of phenotypic expression and with male dominant transmission. Because of its rarity, the best surgical technique and timing remain an open question especially in cases with incomplete triad syndrome.

Imaging in spine and spinal cord malformations

Spinal and spinal cord malformations are collectively named spinal dysraphisms. They arise from defects occurring in the early embryological stages of gastrulation (weeks 2-3), primary neurulation (weeks 3-4), and secondary neurulation (weeks 5-6). Spinal dysraphisms are categorized into open spinal dysraphisms (OSDs), in which there is exposure of abnormal nervous tissues through a skin defect, and closed spinal dysraphisms (CSD), in which there is a continuous skin coverage to the underlying malformation. Open spinal dysraphisms basically include myelomeningocele and other rare abnormalities such as myelocele and hemimyelo(meningo)cele. Closed spinal dysraphisms are further categorized based on the association with low-back subcutaneous masses. Closed spinal dysraphisms with mass are represented by lipomyelocele, lipomyelomeningocele, meningocele, and myelocystocele. Closed spinal dysraphisms without mass comprise simple dysraphic states (tight filum terminale, filar and intradural lipomas, persistent terminal ventricle, and dermal sinuses) and complex dysraphic states. The latter category further comprises defects of midline notochordal integration (basically represented by diastematomyelia) and defects of segmental notochordal formation (represented by caudal agenesis and spinal segmental dysgenesis). Magnetic resonance imaging (MRI) is the preferred modality for imaging these complex abnormalities. The use of the aforementioned classification scheme is greatly helpful to make the diagnosis.

Spinal dysraphism: MR imaging rationale

Spinal cord development occurs through the three consecutive periods of gastrulation (weeks 2-3), primary neurulation (weeks 3-4), and secondary neurulation (weeks 5-6). Spinal cord malformations derive from defects in these early embryonic stages, and are collectively called spinal dysraphisms. Spinal dysraphisms may be categorized clinically into open and closed, based on whether the abnormal nervous tissue is exposed to the environment or covered by skin. Open spinal dysraphisms include myelomeningocele and other rare abnormalities such as myelocele, hemimyelomeningocele, and hemimyelocele, and are always associated with a Chiari II malformation. Closed spinal dysraphisms are further divided into two subsets based on whether a subcutaneous mass is present in the low back. Closed spinal dysraphisms with mass comprise lipomyelocele, lipomyelomeningocele, meningocele, and myelocystocele. Closed spinal dysraphisms without mass comprise simple dysraphic states (tight filum terminale, filar and intradural lipomas, persistent terminal ventricle, and dermal sinuses) and complex dysraphic states. The latter category involves abnormal notochordal development, either in the form of failed midline integration (ranging from complete dorsal enteric fistula to neurenteric cysts and diastematomyelia) or of segmental agenesis (caudal agenesis and spinal segmental dysgenesis). Magnetic resonance imaging is the imaging modality of choice for evaluation of this complex group of disorders.

Surgical strategy for anterior sacral meningocele

A 25-year-old male presented with an anterior sacral meningocele (ASM) manifesting as repeated urinary tract infections. Surgical correction was completed by simple ligation of the thecal sac next to the ostium via sacral laminectomy, and the thickened filum terminale was sectioned. A 22-year-old female presented with an ASM manifesting as transient difficulty in micturition. Subsequent to sacral laminectomy, the thickened filum terminale was sectioned. However, an aberrant nerve root over the ostium made simple ligation hazardous, so that transdural suture around the ostium was carried out. Complete obliteration was confirmed 5 months after the surgery. Magnetic resonance (MR) imaging could clearly demonstrate the involvement of neurologically important structures. Surgical strategy for ASM based on neurosurgical considerations is proposed, because of the frequent association of caudal spinal cord anomaly as well as presacral mass lesion. Intraoperative assistance systems such as endoscopy for cyst content examination and neurophysiological monitorings are recommended. Several months follow up with MR imaging is required to confirm successful surgical correction.

Magnetic resonance imaging of spinal dysraphism

Spinal cord development occurs through three consecutive periods. Gastrulation (weeks 2-3) is characterized by conversion of the embryonic disk from a bilaminar to a trilaminar arrangement and establishment of a notochord. Primary neurulation (weeks 3-4) produces the uppermost nine tenths of the spinal cord. Secondary neurulation and retrogressive differentiation (weeks 5-6) result in formation of the conus tip and filum terminale. Defects in these early embryonic stages produce spinal dysraphisms, which are characterized by anomalous differentiation and fusion of dorsal midline structures. Spinal dysraphisms may be categorized clinically into two subsets. In open spinal dysraphisms, the placode (non-neurulated neural tissue) is exposed to the environment. These disorders include myelomeningocele, myeloschisis, hemimyelomeningocele, and hemimyelocele, and are always associated with a Chiari II malformation. Closed spinal dysraphisms are covered by intact skin, although cutaneous stigmata usually indicate their presence. Two subsets may be identified based on whether a subcutaneous mass is present in the low back. Closed spinal dysraphisms with mass comprise lipomyeloschisis, lipomyelomeningocele, meningocele, and myelocystocele. Closed spinal dysraphisms without mass comprise complex dysraphic states (ranging from complete dorsal enteric fistula to neurenteric cysts, split cord malformations, dermal sinuses, caudal regression, and spinal segmental dysgenesis), bony spina bifida, tight filum terminale, filar and intradural lipomas, and persistent terminal ventricle. Magnetic resonance imaging is the imaging method of choice for investigation of this complex group of disorders.

Complete familial Currarino triad

✓ The Currarino triad is a unique complex of congenital caudal anomalies including anorectal malformation, sacral bone abnormality, and presacral mass. In this report, the authors describe three cases with the complete Currarino triad in a family. The authors treated a 30-year-old mother with an anterior sacral meningocele, her 1-year-old son with a combination of anterior sacral meningocele and dermoid cyst, and her 4-year-old daughter with an epidermoid cyst. These three patients had associated sacral agenesis and anorectal malformations. To the authors' knowledge, this is the first report describing radiological and operative findings of complete familial Currarino triad in which a mother and her two children were affected.

Linkage analysis of a candidate locus (HLA) in autosomal dominant sacral defect with anterior meningocele

Sacral defect with anterior meningocele (SDAM) is a type of caudal dysgenesis. It is present at birth and becomes symptomatic later in life, usually because of obstructive labor in females, chronic constipation, rectal fistula and abscess, or meningitis. The inheritance is autosomal dominant. HLA has been implicated in caudal dysgenesis because of analogy with disorders of the T-locus complex, a tail length determining gene in mice which is linked to the major histocompatibility complex, H-2. Members of a 5-generation family with sacral defect and anterior meningocele (SDAM) were typed with polymorphic markers (dinucleotide repeats D6S89, D6S105, D6S109, and TCTE1) linked to HLA. Two-point and multipoint analysis exclude the HLA region as the location for the SDAM gene in this family.

Anterior-sacral meningocele; value of magnetic resonance imaging and abdominal sonography. A case report

With the presentation of a case of giant anterior sacral meningocele, the evident superiority of magnetic resonance imaging over any other methods for the diagnosis of this rare condition is demonstrated. Ultrasound as a screening tool is often the first to reveal the presence of the intrabdominal cystic abnormality and furthermore is an excellent means for checking the post-operative course. In addition this particular case is interesting because the dural stalk linking the meningocele to the dural abdominal sac was not entirely free from nervous structures inspite of macroscopic appearances to the contrary.

Anterior sacral meningocele occurring in one family. An autosomal dominantly inherited condition

Anterior sacral meningocele is a rare congenital condition. Among 177 individuals familial occurrence was reported only seven times. In this report a family in which five members had anterior sacral meningoceles is presented and an autosomal dominant inheritance is suggested.