Preoperative Evaluation of Craniopagus Twins: Anatomy, Imaging Techniques, and Surgical Management.

Craniopagus twins are a rare congenital malformation in which twins are conjoined at the head. Although there is high prenatal and postnatal mortality for craniopagus twins, successful separation has become more common due to advances in neuroimaging, neuroanesthesia, and neurosurgical techniques. Joined brain tissue, shared arteries and veins, and defects in the skull and dura make surgery technically challenging, and neuroimaging plays an important role in preoperative planning. Drawing on our experience from consultation for multiple successful separations of craniopagus twins, we discuss what radiologists need to know about the anatomy, classification, imaging techniques, and surgical management of craniopagus twins.

Lateral decubitus positioning for cervical nerve root block using CT image guidance minimizes effective radiation dose and procedural time.

BACKGROUND AND PURPOSE: Cervical steroid injections are a minimally invasive means of providing pain relief to patients with cervical radiculopathy. CT guidance offers many potential advantages. We developed a technique with the patient in the lateral position with a lateral needle trajectory to minimize the required needle depth from skin to target and a near-vertical needle trajectory. The aim of this study was to analyze the cohort for complications, procedural time, and effective radiation dose. MATERIALS AND METHODS: This was a retrospective evaluation of a single-center patient cohort. PACS images from the procedures were reviewed for needle depth, procedural time, and CTDI(vol). An anatomically relevant conversion factor was used to calculate the effective dose. RESULTS: One hundred sixteen cases from 110 patients were identified. The average patient age was 55 years. There were no complications. In 50% of cases, C5-6 was targeted. The average time was 6 minutes, and the average effective radiation dose, 0.51 mSv (0.21-2.56 mSv). Needle-insertion length from the skin to the target was highly correlated with a need for >3 needle repositioning adjustments and scan series (ρ = 0.52, P < .001) and increased procedural time (ρ = 0.42, P < .001). The angle of needle insertion relative to the floor was significantly correlated with an increased number of needle adjustments for depths >25 mm and a longer procedural time (ρ = 0.29, P = .01) but not for depths <25 mm. CONCLUSIONS: The lateral patient position with CT guidance is safe and allows use of a short needle in a vertical trajectory. This reduces the number of needle adjustments and imaging series to provide a short procedural time with a low effective radiation dose from the procedure.

Assessment of an introductory cervicocerebral catheter angiography learning program: a pilot study.

BACKGROUND AND PURPOSE: There is no standardized curriculum currently available at most institutions for establishing procedural competency in trainees performing cervicocerebral angiography. The purpose of this study was to evaluate a simple learning program to supplement the teaching of basic cervicocerebral angiography. MATERIALS AND METHODS: An 11-session interactive curriculum was implemented covering anatomic, clinical, and radiographic topics for the novice cervicocerebral angiographer. The target learner was the neuroradiology fellow. Data were gathered regarding fellow comfort level on topics relating to cervicocerebral angiography by using a 5-point Likert scale. Improvement in scores on knowledge-based questions after completion of the curriculum was calculated (McNemar test). Trainee-perceived utility of the program was also recorded by using a 5-point Likert scale. Focus sessions were held at the completion of the curriculum to gather feedback regarding the strengths and weaknesses of the program from participants. RESULTS: Ten subjects were enrolled in this pilot study for 3 years. Topics where participants reported a poor initial comfort level (4 or higher) included selection of injection rates and volumes and reformation of reverse-curve catheters. Trainees demonstrated a statistically significant change in the distribution of scores of 29.3% (49.4%-78.7% correct response rate, P < .0001). The average perceived utility was 1.5 (1 = most useful, 5 = least useful). CONCLUSIONS: This simple learning program was a useful adjunct to the training of fellows in diagnostic cervicocerebral angiography, resulting in quantitative improvements in knowledge.

Zinc oxide-eugenol paste retained in gingival mucosa after primary teeth pulpectomy.

AIM: Long-term follow-up evaluations of pulpectomy in primary teeth have revealed retention of ZOE filling particles in the periapical area even after root resorption. CASE REPORT: This paper reports a case of a child submitted to pulpectomy with ZOE paste in primary teeth. After 28 months, the filling particles remained, having migrated to the alveolar bone from the gingival vestibular mucosa during permanent dentition eruption. Aesthetics required periodontal surgical removal of the paste particles. Primary teeth submitted to pulpectomy should be evaluated carefully both clinically and radiographically to verify radicular and ZOE filling paste resorption. The consequences of retained particles during permanent dentition eruption are unknown.

Bilateral connation of permanent mandibular incisors: a case report.

Connated teeth are the consequences of developmental anomalies leading to the eruption of joined elements. According to current definitions, gemination occurs when one tooth bud tries to divide, while fusion occurs if two buds unite. Clinical experience shows, however, that diagnosis can be complicated due to superimposed anomalies. This report describes a unique case of bilateral fusion of permanent mandibular incisors and discusses the differential diagnosis and possible future treatment options anticipated for this particular case.