Technical and surgical aspects of the sphenopalatine ganglion (SPG) microstimulator insertion procedure.

Cluster headache (CH) is a debilitating, severe form of headache. A novel non-systemic therapy has been developed that produces therapeutic electrical stimulation to the sphenopalatine ganglion (SPG). A transoral surgical technique for inserting the Pulsante SPG Microstimulator into the pterygopalatine fossa (PPF) is presented herein. Technical aspects include detailed descriptions of the preoperative planning using computed tomography or cone beam computed tomography scans for presurgical digital microstimulator insertion into the patient-specific anatomy and intraoperative verification of microstimulator placement. Surgical aspects include techniques to insert the microstimulator into the proper midface location atraumatically. During the Pathway CH-1 and Pathway R-1 studies, 99 CH patients received an SPG microstimulator. Ninety-six had a microstimulator placed within the PPF during their initial procedure. Perioperative surgical sequelae included sensory disturbances, pain, and swelling. Follow-up procedures included placement of a second microstimulator on the opposite side (n=2), adjustment of the microstimulator lead location (n=13), re-placement after initial unsuccessful placement (n=1), and removal (n=5). This SPG microstimulator insertion procedure has sequelae comparable to other oral cavity procedures including tooth extractions, sinus surgery, and dental implant placement. Twenty-five of 29 subjects (86%) completing a self-assessment questionnaire indicated that the surgical effects were tolerable and 90% would make the same decision again.

The importance of in-hospital mortality for patients requiring free tissue transfer for head and neck oncology.

Mortality is a rare but disastrous complication of microvascular head and neck reconstruction. The investigators attempt to identify the procedure-related mortality cases and analyse the causes of death. A retrospective analysis of 804 consecutive free flap procedures during a 19-year period was performed and fatal cases were identified (n=42 deaths). Multivariate logistic regression was employed to determine the association of in-hospital mortality with patient-related characteristics. The 30-day post-operative mortality rate was 1% (8 out of 804 patients), and the in-hospital mortality rate (post-operative deaths in-hospital before or after the 30th post-operative day without discharge) was 5.2% (42 out of 804 patients). Cancer recurrence and metastases related pneumonia were the most common causes of death (n=26, 62%), followed by cardiac, pulmonary, infectious and hepatic/renal aetiologies. Logistic regression analysis revealed that patients with stage IV disease and an operation time of >9h were significantly associated with post-operative mortality. Malignancy-related conditions were the most common causes of death following free flap transfer for head and neck reconstruction. For patients with stage IV head and neck cancer, this aggressive surgical approach should be cautiously justified due to its association with post-operative mortality. To shorten the operation time, experienced microsurgical operation teams are necessary.

Clinical indication for intraoperative 3D imaging during open reduction of fractures of the mandibular angle.

PURPOSE: This retrospective study investigated 3-dimensional (3D) imaging with intraoperative Cone-Beam Computed Tomography (CBCT) in Mandibular Angle Fractures (MAF) treated by open reduction. The aim of this study was to demonstrate the image quality of intraoperative CBCT in this region and the benefit for the patients. METHODS: 83 patients with 86 MAF were included in this study. 8 patients were female and 75 male. Patient age ranged from 11 to 68 years (average age 26.8 years). All patients were examined with the mobile CBCT scanner ARCADIS Orbic 3D (Siemens Medical Solutions, Erlangen, Germany) directly after surgical treatment of the MAF. RESULTS: As a direct result of intraoperative CBCT four patients (5%) underwent intraoperative revision. The intraoperative acquisition of the data sets was uncomplicated and in all cases it was possible to effectively visualise and assess the MAF in 3D quality. CONCLUSION: The results showed that intraoperative CBCT is a reliable imaging technique for real-time intraoperative assessment of treated MAF. Use of the mobile 3D CBCT scanner is easy to integrate into routine practice and offers the advantage that immediate revision surgery can be performed.

Medial orbital wall reconstruction with flexible Ethisorb patches.

OBJECTIVES: The aim of this study was to analyse the long-term result after reconstruction of the medial orbital wall with a flexible, biodegradable material (Ethisorb). MATERIALS AND METHODS: During a period of almost 8 years, 31 patients with a medial orbital wall fracture were analysed retrospectively. Inclusion criteria were patients with a maximum size fracture of the orbital medial wall measuring 1.5-2 cm(2). Exophthalmos, enophthalmos, bulbus motility, diplopia and skin sensation were investigated over a period of 6 months. In all patients, the medial orbital wall was reconstructed with Ethisorb patches. RESULTS: No significant intraoperative complications were detected. No postoperative infection, abscess or seroma was found in any of the patients receiving an Ethisorb patch. CONCLUSIONS: The advantage of the semiflexibility of the Ethisorb patch is that it supplies an anatomically correct fit to the orbital medial wall but does not require fixation by screws or the use of sutures. CLINICAL RELEVANCE: The low rate of reported bulbus motility disturbance, diplopia, exophthalmos and enophthalmos demonstrates acceptable results after medial orbital wall reconstruction using the Ethisorb patch.

Effectiveness of safety vests in pediatric horseback riding.

BACKGROUND: Despite the benefit of safety vests to the reduction of torso injuries in children and adolescents is unclear, its' use is recommended. The aim of the present study is to determine the effectiveness of safety vests actually used in pediatric equestrian activities. PATIENTS AND METHOD: In this case-control-study, we analyzed the accidents of 92 riders aged 18 or younger who fell off a horse onto his/her torso during a period of 18 months. Data were gathered from the clinical records. Additionally, a questionnaire was administered on the day of trauma by the patients and/or their parents. RESULTS: The cases comprised 31 patients who sustained torso injuries. The controls were 61 riders with injuries of other body parts than to the torso. Safety vest use was not associated with a lower risk of torso injuries (OR=1.18, 95% CI (0.50, 2.81), p=0.707). Post hoc power analysis revealed that within such a setting an odds ratio of 0.266 could be found with a power of 80%. CONCLUSION: This study is not able to show an association between wearing a torso protector and protection from torso injuries, probably due to confounding. We did not detect a high effect of safety vest usage in our study population. Whether the development of a new generation of safety vests might be more effective remains unclear. An effective vest should be adapted to the requirements of children and adolescents and should protect the thorax and abdomen, but also the cervical and the lumbar spine.

Microvascular free flaps in head and neck surgery: complications and outcome of 1000 flaps.

This study analyzed the surgical outcome and complications of 1000 microvascular free flaps performed at the authors' institution in Germany, between 1987 and 2010. 972 patients underwent reconstruction with 1000 flaps: 28% latissimus dorsi flaps, 27% radial forearm flaps, 20% iliac crest flaps, 12% fibula flaps, 6% jejunal flaps, 2% anterolateral thigh flaps, and 5% other flaps. 130 failures (7.6%) were encountered, including 58 complete flap failures (44.6%) and 72 partial free-flap failures (55.4%). This study confirms that free flaps are extremely reliable in achieving successful reconstruction of the head and neck, but it is essential that complications be recognized and addressed early in their course to prevent or minimize devastating consequences. Owing to the large number of possible errors in flap transplantation, microsurgeons should always check everything for themselves. The on-duty doctors and nursing staff should not be trusted blindly. Venous thrombosis and cervical haematoma are the most common complications at the recipient site and are mainly responsible for flap failure, while complications occurring at the donor site may result from dehiscence and graft necrosis. When a compromised flap is identified, surgical re-exploration should not be deferred.

A hematogenous spread brain abscess invading the right damaged temporomandibular joint.

We report a rare case of a brain abscess which drained spontaneously in a temporomandibular joint damaged by osteoarthritis. The female patient presented to our hospital with a severe headache and pain in the temporomandibular joint. She showed elevated inflammatory parameters with unknown cause. Magnetic resonance imaging of her whole body revealed a large temporal brain abscess extending into the glenoid fossa of the temporomandibular joint. The brain abscess was incised and drained by neurosurgeons in our hospital and in the same operation we resected the articular disc and the affected part of the right temporomandibular joint. Histological examination confirmed a chronic arthrosis in the resected bone of the temporomandibular joint and an inflammatory abscess in the resected brain tissue. The patient recovered well and the inflammation resolved as seen in postoperative investigations. Magnetic resonance imaging a month later confirmed local consolidation in the brain with no sign of residual inflammation.

Diagnostic and therapeutic aspects in the treatment of gunshot wounds of the viscerocranium.

Gunshot wounds of the viscerocranium are a rare occurrence during times of peace in Europe. The removal of projectiles is recommended; in some cases, however, this is controversial. The material properties of projectiles and destruction of anatomical landmarks make it difficult to determine their precise location. Therefore, navigation systems and cone-beam computed tomography (CT) provide the surgeon with continuous intraoperative orientation in real-time. The aim of this study was to report our experiences for image-guided removal of projectiles, the use of cone-beam computed tomography and the resulting intra- and postoperative complications. We investigated 50 patients with gunshot wounds of the facial skeleton retrospectively, 32 had image-guided surgical removal of projectiles in the oral and maxillofacial region, 18 had surgical removal of projectiles without navigation assistance and in 28 cases we used cone-beam CT in the case of dislocated projectiles and fractured bones. There was a significant correlation (p = 0.0136) between the navigated versus not navigated surgery and complication rate (8 vs. 32%, p = 0.0132) including major bleeding, soft tissue infections and nerve damage. Furthermore, we could reduce operating time while using a navigation system and cone-beam CT (p = 0.038). A high tendency between operating time and navigated surgery (p = 0.1103) was found. In conclusion, there is a significant correlation between reduced intra- and postoperative complications including wound infections, nerve damage and major bleeding and the appropriate use of a navigation system. In all these cases we were able to present reduced operating time. Cone-beam CT plays a key role as a useful diagnostic tool in detecting projectiles or metallic foreign bodies intraoperatively.

Clinical indication for intraoperative 3D imaging during open reduction of fractures of the neck and head of the mandibular condyle.

PURPOSE: This study aimed to evaluate the use of intraoperative cone-beam computed tomography (CBCT) in monitoring the results of repositioning and osteosynthesis of condylar process and head (capitulum) fractures of the mandible to see if CBCT is beneficial for these patients. PATIENTS AND METHODS: Sixty patients (22 females and 38 males, age range 16-79 years, average 36.5 years) with condylar process and head fractures according to the classification of Spiessl and Schroll were treated during the study period. Thirty-four of the 60 patients received a CBCT scan immediately after surgical treatment under aseptic conditions. RESULTS: In all 34 cases, intraoperative CBCT provided high-quality imaging of the condylar process in all three planes. In four patients (11.8%), unsatisfactory reposition or unexpected complications were detected which could immediately be corrected with a surgical revision. CONCLUSION: Intraoperative use of CBCT enables optimization of the surgical outcome for fractures of the condylar process and head of the mandible, reduces postoperative complications, and spares patients from repeated intervention. In addition, intraoperative CBCT enables safer treatment with minimally invasive approaches.

Single nucleotide polymorphism in esophageal cancer related gene 1: an analysis in resected oral squamous cell carcinoma patients.

Esophageal cancer related gene 1 (ECRG1) is a novel candidate tumor suppressor gene in human esophageal squamous cells. Overexpression of ECRG1 protein inhibits tumor cell proliferation. Genetic polymorphisms in coding sequences of the gene may cause functional alterations of the gene product and be associated with higher cancer risk and disease phenotypes. A single nucleotide polymorphism (SNP) (Arg290Gln) found in the coding region of ECRG1 might play a role in susceptibility to esophageal squamous cell carcinoma. This study examined SNPs in ECRG1 in a similar tumor type (oral squamous cell carcinoma; OSCC) and investigated the relationship between SNPs in ECRG1 and the clinical outcome of patients with OSCC. DNA samples of 137 OSCC patients were analyzed for SNP genotypes Arg/Arg, Arg/Gln and Gln/Gln in the coding region (exon 8) of ECRG1. SNP genotypes Arg/Arg were found in 70 (51%), Arg/Gln in 60 (43%) and Gln/Gln in 7 (5%) patients. There was no significant association between genotypes and survival (p=0.77) or relapse free survival (p=0.32). The Gln/Gln genotype had the best survival (not significant) probably due to rare cases of SNP Gln/Gln genotype. Genotype Arg/Arg might be a potential negative prognostic marker in OSCC, but more studies with higher patient numbers are required.

A new imaging modality for intraoperative evaluation of sinus floor augmentation.

The aim of this report was to demonstrate the practicability of a new imaging modality, which allows three-dimensional intraoperative imaging and verification of bone-graft position, and to compare it to the currently available imaging systems. The ARCADIS Orbic 3D, a C-arm-based cone-beam computed tomography scanner developed for intraoperative imaging, was used to examine a previously augmented sinus floor, in order to verify the height and width of the augmentation and to determine whether any of the autogenous and synthetic bone-substitute mixture had penetrated the sinus membrane. Visualization of the entire sinus was possible with the aid of multiplanar reconstructions. Data acquisition and processing took 5 min.

Navigated implantation after microsurgical bone transfer using intraoperatively acquired cone-beam computed tomography data sets.

The use of a combination of intraoperative cone-beam computed tomography (CBCT) and a navigation system via a spinal software platform for the navigated implantation of oral implants after microsurgical bone transfer is described. Intraoperative data sets were generated using Arcadis Orbic 3D (Siemens, Medical Solutions, Erlangen, Germany) and immediately transferred to the VectorVision(2) navigation system (BrainLAB, Feldkirchen, Germany) via the NaviLink interface. In two patients who underwent microsurgical bone transfer for midfacial reconstruction, implants were placed using intraoperatively acquired CBCT data sets for planning and navigated insertion. In both cases, successful realization of the planned implant sites was achieved by the guidance of the drill, leading to rehabilitation of both patients. CBCT data generated by mobile systems are sufficient for the planning of implant position, and can be used for navigated insertion using tools originally developed for spinal surgery.

Learning by doing virtually.

Selective reduction of bone without collateral damage (nerves, teeth) is essential in apicectomy. To test whether skills acquired on a virtual apicectomy simulator (VOXEL-MAN system with integrated force-feedback) are transferable from virtual to physical reality, two groups of trainees were compared. Group 1 received computer-based virtual surgical training before performing an apicectomy in a pig cadaver model. The probability of preserving vital neighboring structures was improved significantly, i.e. six-fold, after virtual surgical training (P<0.001). The average volume of the bony defects created by the trainees of Group 2 (mean: 0.47 ml) was significantly (P<0.001) larger than by the trainees of Group 1 (mean: 0.25 ml). Most importantly, the ability to objectively self-assess performance was significantly improved after virtual training. Training with a virtual apicectomy simulator appears to be effective, and the skills acquired are transferable to physical reality.

Validation of a new training tool for ultrasound as a diagnostic modality in suspected midfacial fractures.

The aim of this study was to test a previously described training tool for ultrasound for use as a first-line imaging modality. Navigated sonography was performed in 10 patients with midfacial fractures diagnosed using computed tomography (CT). One examiner ranked his sonographic findings regarding the presence of a fracture on six predefined anatomic landmarks on a scale from 1 to 5. These results were correlated with CT findings by displaying fused images. In all but three patients fractures were correctly identified using sonography. In the remaining three patients the examiner was unable to determine whether a fracture was present or not. Normally, these patients would have been subjected to conventional radiographs. Ultrasound proved to be a reliable first-line imaging modality for the investigation of suspected midfacial fractures in daily clinical practice, resulting in decreased radiation exposure since conventional radiographs are omitted. According to this algorithm, patients with sonographically confirmed midfacial fractures are examined for surgical planning using cone-beam CT.

Diagnostic criteria for the detection of mandibular osteomyelitis using cone-beam computed tomography.

OBJECTIVES: To investigate the usefulness of cone-beam computed tomography (CBCT) in cases of suspected osteomyelitis (OM) of the mandible. METHODS: 13 patients with clinical suspected OM of the mandible underwent cone-beam computed tomography with the NewTom QR-DVT 9000. After CBCT revealed signs confirming the diagnosis of OM, biopsies were performed. Only cases in which histology confirmed the OM were included in this study. RESULTS: CBCT sufficiently depicts OM-typical lesions like osteolytic and osteosclerotic areas as well as periosteal reaction, ill-defined cortical borders and sequestra. CONCLUSIONS: Because the local extension of the disease and its relationship to anatomic structures can be sufficiently detected by CBCT, we see an important additional indication for the usage of CBCT. With regard to distinct cases CBCT combined with scintigraphy seems to be a sufficient diagnostic strategy concerning suspected OM.