Ying-An Chen

Management of acute traumatic retrobulbar haematomas: A 10-year retrospective review

BACKGROUND Retrobulbar haematoma formation is a known complication following facial trauma involving the orbits. This is an important clinical entity as it can lead to permanent vision loss if not appropriately managed in the acute setting. METHODS From 1999 to 2009, 2586 patients presented to the Chang Gung Memorial Hospital with orbital fractures. Eight patients presented with nine retrobulbar haematomas. A retrospective review of the patients medical records was performed. Analysis of visual outcomes was performed based on the improvement degree (ID) formula. RESULTS The average age of our patients is 24.5 years with the most common cause of trauma being motor vehicle (motorcycle) collisions. Visual acuity and the light reflex were abnormal in all patients. Five patients (case #1-5) demonstrated an absent relative afferent pupillary defect (RAPD). Computed tomography imaging confirmed the presence of a retrobulbar haematoma in all patients. The average follow-up was 14.5 months (range: 6-20 months). Management was divided into three cohorts: observation alone, medical therapy alone or a combined surgical and medical therapy. The best visual outcomes (ID=82%) were achieved in the combined treatment group. The worst outcomes (ID=42%) were in the medical therapy alone group. CONCLUSION In review of our experience, we have found that the presence or absence of an RAPD is the most sensitive indicator of optic nerve compromise and necessity for intervention. An algorithm was also developed based on this study. Once a decision is made to intervene on a retrobulbar haematoma, both medical and surgical therapies should be instituted with a priority given to timely decompression of the orbit.

The stability of mandibular prognathism corrected by bilateral sagittal split osteotomies: a comparison of bi-cortical osteosynthesis and mono-cortical osteosynthesis

This study evaluated the differences in surgical changes and post-surgical changes between bi-cortical and mono-cortical osteosynthesis (MCO) in the correction of skeletal Class III malocclusion with bilateral sagittal split osteotomies (BSSOs). Twenty-five patients had bi-cortical osteosynthesis (BCO), 32 patients had mono-cortical fixation. Lateral and postero-anterior cephalometric radiographs, taken at the time of surgery, before surgery, 1 month after surgery, and on completion of orthodontic treatment (mean 9.9 months after surgery), were obtained for evaluation. Cephalometric analysis and superimposition were used to investigate the surgical and post-surgical changes. Independent t-test was performed to compare the difference between the two groups. Pearsons correlations were tested to evaluate the factors related to the relapse of the mandible. The sagittal relapse rate was 20% in the bi-cortical and 25% in the mono-cortical group. The forward-upward rotation of the mandible in the post-surgical period contributed most of the sagittal relapse. There were no statistically significant differences in sagittal and vertical changes between the two groups during surgery and in the post-surgical period. No factors were found to correlate with post-surgical relapse, but the intergonial width increased more in the bi-cortical group. The study suggested that both methods of skeletal fixation had similar postoperative stability.

Comparison of different hypotensive anaesthesia techniques in orthognathic surgery with regard to intraoperative blood loss, quality of the surgical field, and postoperative nausea and vomiting

Sixty-three consecutive patients undergoing bimaxillary surgery between June and August 2015 were included in this study. Twenty-one patients were included in each of three study groups. In group 1, sevoflurane was the sole maintenance anaesthesia agent used; in group 2, propofol was the predominant agent, in addition to a reduced amount of sevoflurane; in group 3, patients received sevoflurane until fixation was completed, at which point it was switched to propofol. The mean intraoperative blood loss (ml) was 707.14±290.74 in group 1, 917.62±380.30 in group 2, and 750.00±331.84 in group 3; the difference between groups 1 and 2 was significant (P=0.047). The mean score for the quality of surgical field assessment was 1.32±0.44 in group 1, 2.04±0.49 in group 2, and 1.45±0.53 in group 3 (P=0.003). The postoperative nausea and vomiting (PONV) rate was 28.6% in group 1, 9.5% in group 2, and 14.3% in group 3 (P=0.343). The quality of the surgical field was significantly better in groups 1 and 3 than in group 2. The average blood loss in group 1 was also significantly less than in group 2. The PONV rates were lower than those reported in other studies.

Iohexol oral rinse to differentiate the palatoglossal surfaces in computed tomography of patients with obstructive sleep apnoea

Craniofacial Center, Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital and Chang Gung University, 5 Fu-Shin Street, wei Shan, Taoyuan 333, Taiwan Craniofacial Research Center, Chang Gung Memorial Hospital, 5 Fu-Shin Street, Kwei Shan, Taoyuan 333, Taiwan Department of Oral and Maxillofacial Surgery, Tokyo Women’s Medical University School of Medicine, 8-1 Kawada-cho, Shinjyuku-ku, Tokyo, 67-8666, Japan Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, 5 Fu-Shin Street, Kwei Shan, Taoyuan 333, Taiwan Dr. Edmund Chan’s Clinic, Unit 602-3, Manning House, 48 Queen’s Road Central, Central, Hong Kong

Pre-surgical regional blocks in orthognathic surgery: prospective study evaluating their influence on the intraoperative use of anaesthetics and blood pressure control

In orthognathic surgery, maxillary (CNV2) and mandibular (CNV3) divisions of the trigeminal nerve can be blocked successfully prior to surgery. In this study, it was hypothesized that regional blocks (nerve block over a particular region: bilateral CNV2 and CNV3 divisions of the trigeminal nerve) would decrease the total requirement for intraoperative anaesthetic agents and facilitate the process of hypotensive anaesthesia. Local anaesthesia containing 1/100,000 epinephrine and 10ml 0.5% levobupivacaine was injected into the planned incisions in 50 patients. Twenty-five patients (group A) underwent orthognathic surgery without regional blocks and another 25 patients (group B) underwent surgery with regional blocks. The anaesthetic protocol was the same in both groups and administered by a single anaesthesiologist. The mean arterial pressure was recorded at several points throughout the operation, as well as all the medications used. The blood loss and the amounts of medications administered were lower in group B than in group A. In patients receiving regional blocks, the amounts of fentanyl and nicardipine required were significantly lower. The use of pre-emptive anaesthesia in orthognathic surgery may reduce the overall amounts of medications required for hypotensive anaesthesia, facilitate the intraoperative control of blood pressure, and decrease intraoperative blood loss.