CASE REPORT MR Imaging Characteristics of Cervical ...

1 39 Chin J Radiol 2001; 26: 39-44MR Imaging Characteristics of CervicalNeurenteric Cysts: Two Case ReportsYANG-KAIFAN1 JON-KWAYHUANG1,2 CHIN-YINSHEU1 TAI-DONGWONG3 Department of Radiology1, Mackay Memorial Hospital;Department of Radiology2, Taipei Medical University;Division of Pediatric Neurosurgery3, Institute of Neuroscience, Taipei- Veterans General Hospital, Taiwan neurenteric cysts are rare causes of spinalcord compression in infants and congenital lesions arise from abnormalseparation of the endoderm and neuroectodermduring embryogenesis. A diagnosis ofneurenteric cysts prior to surgery is , the authors REPORT on 2 cases withneurenteric cysts. The preoperative MR imagesof both cases showed cystic lesions with lowsignal intensity on T1-weighted images andhigh signal intensity on T2-weighted images,just like the intensity pattern of cerebrospinalfluid.

2 One was intradural extramedullary andthe other was intramedullary in location. Theliterature is also words: Magnetic resonance image; Cervical vertebrae; Spinal cord compressionNeurenteric cysts are rare congenital lesions,and they are even rarer when locatedintramedullarily. MR images are very helpful for adiagnosis of neurenteric cysts and preoperativeplanning of treatment. Complete recovery ofneurological functions is usually possible aftersurgical decompression, but the chance ofrecurrence still remains to be determined. Theauthors present 2 cases with Cervical neurentericcysts: one was intradural extramedullary and theother was intramedullary in location. The clinicalfeatures, MR image Characteristics , andmanagement of neurenteric cysts are cysts must be considered whenever acystic lesion is present within the spinal REPORTSCase 1A 10-year-old girl complained of left forearmand shoulder pain 3 months prior to symptoms resolved after medical 2 months after the initialsymptoms, the girl presented with neck stiffnessand ataxia.

3 Examination on admission revealed apositive Babinski s sign on the right side. Musclepower was generally normal in all extremities, andthe right supinator and knee reflexes showedhyperreflexia. All her sensory functions wereintact. Other physical examinations wereunremarkable. A non-enhanced brain CT and subsequent plainradiograph of the thoracic spine were resonance images (MRIs) of thecervicothoracic spine showed an intraduralextramedullary cystic lesion anterior to thecervical spinal cord which was isointense tocerebrospinal fluid (CSF) on T1-weighted imagesCASE REPORTR eprint requests to: Dr. Jon-Kway HuangDepartment of Radiology, Mackay Memorial Hospital, 92 Chung-Shan N.

4 Rd., Sec. 2, Taipei 104, Taiwan, (T1 WIs) (Figure 1a) and slightly hyperintense toCSF on T2-weighted images (T2 WIs) (Figure 1b).Compression of the spinal cord was seen. Thebony vertebrae and intervertebral discs appearednormal. The patient was then transferred toanother hospital for surgery. After decompressionof the cyst with a fine needle inserted between thelamina of C6 and C7, laminectomy from C4 to C7was performed with gross resection of theintradural extramedullary cystic lesion. Aneurenteric cyst lined by cuboidal to ciliatedcolumnar epithelium was proven by girl had no complaints, and her neurologicfunctioning was normal 6 months after 2A 5-year-old boy was first admitted to ourhospital because of a 2-day history of intermittentfever, headaches, neck stiffness, and unstablegait.

5 Physical examination at the time ofadmission was unremarkable. The neurologicalexamination revealed negative Kernig's andBrudzinski s signs. The deep tendon reflex was2+ in the bilateral upper extremities and 3+ inboth lower extremities. Meningitis and anintracranial lesion were the first 2 examination showed no significantabnormality, and no growth of microorganismswas seen in CSF and urine cultures. Brain CT wasnormal. An MRI of the Cervical spine revealed anoval, sharply demarcated intramedullary cysticlesion with low signal intensity at the level of C4to C6 on coronal and sagittal T1 WIs (Figure 2a),which became bright on T2 WIs (Figure 2b). Noenhancement was seen after intravenous injectionof contrast medium.

6 Under the impression of anintramedullary cystic lesion, the boy wasscheduled to have an operation. After totallaminectomy of C4 to C5 with intraduralexploration, a cystic mass was found in the cordfrom the level of C3 to C5. The cyst was thenpunctured and partially removed under amicroscope. Histology showed only densecollagenous tissue that may have belonged to thedura or ligaments. No definitive diagnosis 14 months later, the boy was admitted toour hospital again due to progressive neck painand stiffness. His muscle power was generallynormal and sensations were intact. A repeat MRIof the Cervical spine showed a focal area of anintramedullary lesion at the level of C4 and C5with predominant iso-signal intensity andstippling of high signal intensity spots on T1 WIs(Figure 3a).

7 There was evidence of homogeneousand focal lobulated high signal intensity of thislesion demonstrated on a gradient echo protondensity image and T2WI (Figure 3b). AfterCervical neurenteric Cysts40 Figure MRimages of Case 1. image(TR/TE=500/25) showing awell-demarcated intraduralextramedullary cystic lesionwith anterior compression onthe cord. The lesion ishypointense to the cord andisointense to CSF. having becomesignificantly hyperintense tothe cord and only slightlyhyperintense to CSF on asagittal T2-weighted image(3000/100). The bonyvertebrae of thecervicothoracic spine appearintact. 1a1bCervical neurenteric Cysts41intravenous contrast medium administration, thislesion showed no significant abnormalenhancement.

8 During operation, the specimen wassent to the lab for freeze-sectioning. Microscopicexamination revealed that a portion of the cysticwall was composed of a thin fibrous or glioticwall lined by pseudostratified ciliated columnarepithelium with abundant vacuolar cytoplasm,suggesting a single layer of intestinal-typeepithelium (Figure 4). Focal incompletesquamous metaplasia was present. The subsequentpermanent pathologic specimen confirmed theresult. On the basis of these histologic features,the definitive diagnosis was a neurenteric images of Case2 obtained before the firstoperation. T1-weighted image (450/20)revealing a well-demarcatedcystic lesion within thecervical spinal cord with lowsignal intensity similar to cord is expanded.

9 T2-weighted image(2800/100) showing that thecyst is hyperintense to thecord and is almost the same images of Case2 obtained before the secondoperation. T1-weighted image (500/25)showing that the previouscystic lesion has becomeisointense with peripheral highsignal intensity spots after thefirst operation (arrowhead). a sagittal T2-weightedimage (4000/100), the lesion,clearly identifiable, ishyperintense to the cord andslightly hyperintense to neurenteric Cysts42 The postoperative course was uneventful, and thepatient s condition gradually improved during the5 months after surgery. DISCUSSIONA lthough various theories have been proposedto explain the formation of neurenteric cysts, it iswidely accepted that these cysts originate fromabnormal separation of the endoderm andneuroectoderm in the third week of embryoniclife, resulting in the inclusion of endodermalelements in the spinal canal.

10 They are alsothought to be components of the split notochordsyndrome [1]. Woo and Sharr concluded thatthere seemed to be 2 types of cysts: developmental cysts and teratomatous cysts . Developmental cysts are typically found in thecervical segment lying anterior to the spinal cordwith no associated spinal defects. For this type,symptoms usually appear after the second decadeor later. By contrast, teratomatous cysts aretypically found at the level of the conus lyingposterior to the cord or roots and are frequentlyassociated with spinal defects. Generally,symptoms of the latter type appear early in lifeprobably due to major abnormalities [2].The clinical presentations of neurenteric cystsare mainly the results of spinal cord and nerveroot compression.