The internal trabecular bone structure of the odontoid process of the axis. A retrospective single-center comparative study in patients following cervical trauma.

Background Odontoid C2 fractures account for 9% to 15% of adult cervical spine fractures. The aim of this study is to report the incidence of a previous described Y-shaped trabecular bone structure (TBS) in the odontoid process in a larger sample of patients who performed a CT cervical scan following a cervical trauma to investigate if its absence can increase the risk of the odontoid process fracture of the axis. Methods A retrospective review of 245 patients who performed a CT cervical scan in our University Hospital, as results of cervical spine injury, was performed during a 12-month period between May 2020 and May 2021. Results The presence of a Y-shaped TBS at the odontocentral synchondrosis level was observed in 165 patients that is 67.3% of whole population included in this study. Eighteen patients (7.3%) reported an odontoid type II C2 fracture. Among patients with odontoid type II C2 fracture, the Y-shaped TBS at the odontocentral synchondrosis level was observed in 8 (44.4%) of them. The presence of the Y-shaped TBS at the odontocentral synchondrosis level was statistically more frequently observed in patients without odontoid process fracture (69.2% Vs 30.8%) compared to patients who developed odontoid process fracture (44.4 % Vs 55.6%) after a cervical trauma (p = 0.03). Conclusions This study showed the crucial role of this Y-shaped TBS in biomechanical structural dynamics of the C1-C2 joint and its significant clinical relevance in odontoid fractures of the axis.

Disseminated bone metastases from occult thyroid cancer effectively treated with debulking surgery and a single dosimetry-guided administration of radioiodine.

In this paper we report on a successful management of multiple bone metastases from differentiated thyroid cancer. In 2007, a 75-year-old female patient, previously referred for thyroidectomy for multinodular goiter, underwent surgical removal of a lumbar mass with histological findings of metastasis from well differentiated thyroid cancer. After surgery, serum thyroglobulin (sTg) was 204.4 ng/mL. A diagnostic/dosimetric (123)I WBS was performed, following stimulation by rTSH. Serial WBSs were acquired, along with SPECT/CT and bone scan for localization of lesions. sTg raised to 3.810 ng/mL, and (123)I WBS showed thyroid remnants and numerous areas with high iodine-uptake corresponding to skeletal sites, the two largest loading on the skull, with osteolytic pattern. Calculated radiation absorbed dose for skull lesions, determined by mean of MIRD methodology, was 63.5 mGy/MBq. The patient underwent surgical removal of the two major skull lesions. Successively, 100 mCi (131)I was administered after stimulation by rTSH, with stimulated sTg 297 ng/mL. After 8 months, diagnostic WBS was negative both for remnants and metastases and rTSH-stimulated Tg was 0.6 ng/mL. To date, the patient has maintained sTg values <1 ng/mL during L-T4 suppressive therapy and after rTSH stimulations. In this unusual case of extensive bone cancerous involvement with high iodine avidity, a multidisciplinary approach based on surgery and dosimetry-guided radiometabolic therapy allowed to accurately assess the patient, execute a small number of treatments and achieve a complete remission of the disease in a very short time, with no additive morbidity.

Hydrocephalus following bilateral dumbbell-shaped c2 spinal neurofibromas resection and postoperative cervical pseudomeningocele in a patient with neurofibromatosis type 1: a case report.

Study Design Case report. Objective To present a rare case of hydrocephalus following bilateral dumbbell-shaped C2 spinal neurofibromas resection and postoperative cervical pseudomeningocele in a patient with neurofibromatosis type 1 (NF1). Methods The patient's clinical course is retrospectively reviewed. A 37-year-old man affected by NF1 referred to our department for progressive weakness of both lower extremities and gait disturbance. Radiological imaging showed bilateral dumbbell-shaped C2 spinal neurofibromas. After its resection, at the 1-month follow-up evaluation, the patient reported headache and nausea. A CT brain scan showed a postoperative cervical pseudomeningocele and an increase in the ventricular sizes, resulting in hydrocephalus. Results A ventriculoperitoneal shunting was performed using a programmable valve opening pressure set to 120 mmH20. After surgery, the patient's neurological status markedly improved. Conclusion Hydrocephalus must be considered a possible complication of cervical spine tumor resection.