Pterygopalatine Fossa Anatomy for a Surgical Approach to Sphenopalatine Ganglion.

The sphenopalatine ganglion is an extracranial neural structure within the pterygopalatine fossa. Modulation of this region via implantation of a neuromodulatory device presents a novel therapy for the treatment of facial and head pain. Yet sex, race, and genetic factors contribute to morphological variations between individuals. This study defines the standards and variations of the bony landmarks surrounding the pterygopalatine fossa. One hundred dry skulls were analyzed from the Hamann-Todd osteological collection. Ten anatomical dimensions were measured on each side of the face for each specimen (vidian foramen, zygomatic buttress, zygomatic maxillary suture, pyriform rim, infraorbital rim, pterygoid maxillary suture, greater palatine foramen, auditory canal, and pterygoid fossa). A statistical analysis was performed for both sides of the face based on sex and race. When stratified by sex, 7 of the 10 measurements revealed a statistically significant difference bilaterally. When stratified by race, 5 of the 10 measurements demonstrated a statistically significant difference bilaterally. Both male and African American skulls showed greater hemifacial values bilaterally when compared with their respective counterparts. The only statistically significant measurement on both the left and right sides of all skulls was the length from the vidian foramen to the infraorbital rim. Defining the anatomical mean distance between skull landmarks and highlighting differences between sex and race not only provides further insight into relative skull anatomy, but also sets the stage for device innovation.

First imaging results of an intraindividual comparison of (11)C-acetate and (18)F-fluorocholine PET/CT in patients with prostate cancer at early biochemical first or second relapse after prostatectomy or radiotherapy.

PURPOSE: (18)F-Fluorocholine (FCH) and (11)C-acetate (ACE) PET are widely used for detection of recurrent prostate cancer (PC). We present the first results of a comparative, prospective PET/CT study of both tracers evaluated in the same patients presenting with recurrence and low PSA to compare the diagnostic information provided by the two tracers. METHODS: The study group comprised 23 patients studied for a rising PSA level after radical prostatectomy (RP, 7 patients, PSA ≤ 3 ng/ml), curative radiotherapy (RT, 7 patients, PSA ≤ 5 ng/ml) or RP and salvage RT (9 patients, PSA ≤ 5 ng/ml). Both FCH and ACE PET/CT scans were performed in a random sequence a median of 4 days (range 0 to 11 days) apart. FCH PET/CT was started at injection (307 ± 16 MBq) with a 10-min dynamic acquisition of the prostate bed, followed by a whole-body PET scan and late (45 min) imaging of the pelvis. ACE PET/CT was performed as a double whole-body PET scan starting 5 and 22 min after injection (994 ± 72 MBq), and a late view (45 min) of the prostate bed. PET/CT scans were blindly reviewed by two independent pairs of two experienced nuclear medicine physicians, discordant subgroup results being discussed to reach a consensus for positive, negative end equivocal results. RESULTS: PET results were concordant in 88 out of 92 local, regional and distant findings (Cohen's kappa 0.929). In particular, results were concordant in all patients concerning local status, bone metastases and distant findings. Lymph-node results were concordant in 19 patients and different in 4 patients. On a per-patient basis results were concordant in 22 of 23 patients (14 positive, 5 negative and 3 equivocal). In only one patient was ACE PET/CT positive for nodal metastases while FCH PET/CT was overall negative; interestingly, the ACE-positive and FCH-negative lymph nodes became positive in a second FCH PET/CT scan performed a few months later. CONCLUSION: Overall, ACE and FCH PET/CT showed excellent concordance, on both a per-lesion and a per-patient basis, suggesting that both tracers perform equally for recurrent prostate cancer staging.

Electrical stimulation of sphenopalatine ganglion for acute treatment of cluster headaches.

INTRODUCTION: Cluster headaches (CH) are primary headaches marked by repeated short-lasting attacks of severe, unilateral head pain and associated autonomic symptoms. Despite aggressive management with medications, oxygen therapy, nerve blocks, as well as various lesioning and neurostimulation therapies, a number of patients are incapacitated and suffering. The sphenopalatine ganglion (SPG) has been implicated in the pathophysiology of CH and has been a target for blocks, lesioning, and other surgical approaches. For this reason, it was selected as a target for an acute neurostimulation study. METHODS: Six patients with refractory chronic CH were treated with short-term (up to 1 hour) electrical stimulation of the SPG during an acute CH. Headaches were spontaneously present at the time of stimulation or were triggered with agents known to trigger clusters headache in each patient. A standard percutaneous infrazygomatic approach was used to place a needle at the ipsilateral SPG in the pterygopalatine fossa under fluoroscopic guidance. Electrical stimulation was performed using a temporary stimulating electrode. Stimulation was performed at various settings during maximal headache intensity. RESULTS: Five patients had CH during the initial evaluation. Three returned 3 months later for a second evaluation. There were 18 acute and distinct CH attacks with clinically maximal visual analog scale (VAS) intensity of 8 (out of 10) and above. SPG stimulation resulted in complete resolution of the headache in 11 attacks, partial resolution (>50% VAS reduction) in 3, and minimal to no relief in 4 attacks. Associated autonomic features of CH were resolved in each responder. Pain relief was noted within several minutes of stimulation. CONCLUSION: Sphenopalatine ganglion stimulation can be effective in relieving acute severe CH pain and associated autonomic features. Chronic long-term outcome studies are needed to determine the utility of SPG stimulation for management and prevention of CH.

Noninvasive stress testing of myocardial perfusion defects: head-to-head comparison of thallium-201 SPECT to MRI perfusion.

BACKGROUND: To evaluate the diagnostic value of magnetic resonance imaging (MRI) of myocardial perfusion in the assessment of flow-limiting epicardial stenosis in a head-to-head comparison with abnormal thallium-201 ((201)TI) single photon emission tomography (SPECT) studies in patients with predominantly known coronary artery disease (CAD). METHODS AND RESULTS: Twenty-one patients (mean age 65 +/- 10 years) with reversible myocardial perfusion defects on (201)TI-SPECT images during dipyridamole-stimulated hyperemia were recruited for study purpose. Within 5 days of the (201)TI-SPECT study, myocardial perfusion was studied again with MRI during dipyridamole stimulation and at rest. Overall, (201)TI-SPECT identified 30 reversible regional perfusion defects. The sensitivity to detect hypoperfused segments was 70% (21/30) with the GRE-MRI perfusion analysis with (201)TI-SPECT as reference. When patients were subgrouped according to the extent of regional reversible perfusion defects on (201)TI-SPECT, mild- (SDS: 2-4), moderate- (SDS: 5-8), and severe- (SDS > 8) perfusion defects were also identified by GRE-MRI perfusion analysis in 75% (6/8), in 56% (9/16) and 100% (6/6), respectively. CONCLUSIONS: GRE-MRI first-pass stress perfusion imaging may not identify up to 30% of mild-to-moderate perfusion defects in a group of preselected patients with predominantly known CAD and abnormal (201)TI-SPECT studies.

Acute treatment of intractable migraine with sphenopalatine ganglion electrical stimulation.

BACKGROUND: We report preliminary results of a novel acute treatment for intractable migraine. The sphenopalatine ganglion (SPG) has sensorimotor and autonomic components and is involved in migraine pathophysiology. METHODS: In 11 patients with medically refractory migraine, the sphenopalatine fossa was accessed with a 20-gauge needle using the standard infrazygomatic transcoronoid approach under fluoroscopy. Patients underwent temporary unilateral electric stimulation of the SPG with a Medtronic 3057 test stimulation lead after induction of full-blown migraine. Both sham and active stimulations with different settings were carried out for < or =60 minutes, and then the lead was removed. RESULTS: In 11 evaluations, 2 patients were pain-free within 3 minutes of stimulation. Three had pain reduction; 5 had no response; 1 was not stimulated. Five patients had no pain relief. Stimulation settings: mean amplitude of 1.2V, mean pulse rate of 67 Hz, mean pulse width of 462 micros. Lack of headache relief appeared linked to suboptimal lead placement, poor physiologic sensory response to localization stimulation, and diagnosis of medication overuse headache. CONCLUSION: This study suggests a possible role for SPG stimulation in the treatment of refractory migraine headaches.

Robotically assisted gynaecological surgery.

Industry has used robots successfully for fine, delicate, repetitive tasks for decades. Recently, robots have been introduced into clinical medicine and specifically into the surgical suite. Voice algorithms have been developed that allow voice activation of some types of equipment in the operating room, such as the laparoscope or the light source. Advances in computer software have allowed a computer controller to translate a surgeon's movements from the handles located in a console to the robotic arms that hold the surgical instruments. This console is placed away from the surgical table. Clinical experience is limited and there are few published clinical trials. The initial trials have focused on laparoscopic microsuturing such as that performed during coronary bypass surgery or tubal anastomosis. Preliminary results have demonstrated that laparoscopic coronary bypass surgery with the internal mammary artery can be achieved. In gynaecological surgery, laparoscopic tubal reanastomosis can be performed using the same technique that has been used traditionally at laparotomy. Future clinical trials will assess whether other gynaecological procedures can be performed with robotic assistance.

Target volume definition in high-risk prostate cancer patients using sentinel node SPECT/CT and 18 F-choline PET/CT.

BACKGROUND: To assess the influence of sentinel lymph nodes (SNs) SPECT/CT and 18 F-choline (18 F-FCH) PET/CT in radiotherapy (RT) treatment planning for prostate cancer patients with a high-risk for lymph node (LN) involvement. METHODS: Twenty high-risk prostate cancer patients underwent a pelvic SPECT acquisition following a transrectal ultrasound guided injection of 99mTc-Nanocoll into the prostate. In all patients but one an 18 F-FCH PET/CT for RT treatment planning was performed. SPECT studies were coregistered with the respective abdominal CTs. Pelvic SNs localized on SPECT/CT and LN metastases detected by 18 F-FCH PET/CT were compared to standard pelvic clinical target volumes (CTV). RESULTS: A total of 104 pelvic SNs were identified on SPECT/CT (mean 5.2 SNs/patient; range 1-10). Twenty-seven SNs were located outside the standard pelvic CTV, 17 in the proximal common iliac and retroperitoneal regions above S1, 9 in the pararectal fat and 1 in the inguinal region. SPECT/CT succeeded to optimize the definition of the CTV and treatment plans in 6/20 patients due to the presence of pararectal SNs located outside the standard treatment volume. 18 F-FCH PET/CT identified abnormal tracer uptake in the iliac LN region in 2/19 patients. These abnormal LNs were negative on SPECT/CT suggesting a potential blockade of lymphatic drainage by metastatic LNs with a high tumour burden. CONCLUSIONS: Multimodality imaging which combines SPECT/CT prostate lymphoscintigraphy and 18 F-FCH PET/CT identified SNs outside standard pelvic CTVs or highly suspicious pelvic LNs in 40% of high-risk prostate cancer patients, highlighting the potential impact of this approach in RT treatment planning.

[¹¹C]acetate PET/CT visualizes skeletal muscle exercise participation, impaired function, and recovery after hip arthroplasty; first results.

PURPOSE: Based on skeletal muscle acetate physiology we aimed studying muscle function after hip arthroplasty with [(11)C]acetate PET. PROCEDURES: Two male patients were investigated 3 and 12 weeks after hip arthroplasty with muscle [(11)C]acetate PET/CT performed at rest and exercise. Median muscle SUV(mean) were calculated on three non-consecutive transverse PET slices. RESULTS: The four exercise PET/CT showed, compared with rest, consistent increase in [(11)C]acetate uptake in active muscles contralateral to surgery. On the arthroplasty side most muscles showed symmetric activity increase under exercise both at 3 and 12 weeks after surgery, but four muscles showed only minor activity increase at 3 weeks. At 3 months, functional recovery of the latter four muscles was observed. CONCLUSION: Consistent increase in [(11)C]acetate uptake in healthy muscles under exercise compared with rest was observed by PET/CT. Transiently impaired muscle function 3 weeks after surgery recovered at 3 months. These first observations merit further investigation.

18F-fluorocholine PET-guided target volume delineation techniques for partial prostate re-irradiation in local recurrent prostate cancer.

BACKGROUND AND PURPOSE: We evaluate the contribution of (18)F-choline PET/CT in the delineation of gross tumour volume (GTV) in local recurrent prostate cancer after initial irradiation using various PET image segmentation techniques. MATERIALS AND METHODS: Seventeen patients with local-only recurrent prostate cancer (median=5.7 years) after initial irradiation were included in the study. Rebiopsies were performed in 10 patients that confirmed the local recurrence. Following injection of 300 MBq of (18)F-fluorocholine, dynamic PET frames (3 min each) were reconstructed from the list-mode acquisition. Five PET image segmentation techniques were used to delineate the (18)F-choline-based GTVs. These included manual delineation of contours (GTV(man)) by two teams consisting of a radiation oncologist and a nuclear medicine physician each, a fixed threshold of 40% and 50% of the maximum signal intensity (GTV(40%) and GTV(50%)), signal-to-background ratio-based adaptive thresholding (GTV(SBR)), and a region growing (GTV(RG)) algorithm. Geographic mismatches between the GTVs were also assessed using overlap analysis. RESULTS: Inter-observer variability for manual delineation of GTVs was high but not statistically significant (p=0.459). In addition, the volumes and shapes of GTVs delineated using semi-automated techniques were significantly higher than those of GTVs defined manually. CONCLUSIONS: Semi-automated segmentation techniques for (18)F-choline PET-guided GTV delineation resulted in substantially higher GTVs compared to manual delineation and might replace the latter for determination of recurrent prostate cancer for partial prostate re-irradiation. The selection of the most appropriate segmentation algorithm still needs to be determined.

3-D microfabricated electrodes for targeted deep brain stimulation.

This work presents a novel 4-sided, 16-channel deep brain stimulation electrode with a custom flexible high-density lead for connectivity with pulse generation electronics. The 3-dimensional electrode enables steering the current field circumferentially. The electrode is fabricated in pieces by micromachining and microfabrication techniques; the pieces are then assembled mechanically to form the electrode, after which the lead is connected. The electrode is modeled by finite element analysis and tested in vitro to validate the design concept, i.e., targeted stimulation. Simulation and experimental results for a targeted stimulation show close agreement. With a symmetric bipolar stimulation configuration, within a 3 mm radius, the electric potential in front of the activated side is at least 3.6 times larger than that on the corresponding two adjacent, not-activated sides, and 9 times larger than the corresponding opposite, not-activated side.

F-18 fluorodeoxyglucose (FDG) PET in the diagnosis of malignant transformation of fibrous dysplasia in the pelvic bones.

Fibrous dysplasia (FD) is a benign dysplastic pathology of bone-forming mesenchymal cells, resulting in replacement of trabecular bone by abnormal fibrous and immature osseous tissue. FD can be either monostotic or polyostotic, is more often unilateral, and can be part of the McCune-Albright syndrome (MIM 174800). Sarcomatous degeneration in FD is rare, ranging from less than 1% in monostotic forms to 4% in the McCune-Albright syndrome. We report the case of a 59-year-old woman with monostotic FD of the left ischium, known for over 30 years, who developed sarcomatous transformation in a low-grade spindle-cell sarcoma. The value of F-18 fluorodeoxyglucose positron emission tomography in the early diagnosis of malignant transformation, the evaluation of distant metastasis, as well as monitoring the efficacy of chemotherapy are discussed.

Impact of treatment with rosiglitazone or metformin on biomarkers for insulin resistance and metabolic syndrome in patients with polycystic ovary syndrome.

BACKGROUND: There is increasing evidence that insulin resistance (IR) has an important implication in the pathogenesis of polycystic ovary syndrome (PCOS), a common endocrinopathy in women. This study was performed to investigate the impact of different treatments for IR on five currently discussed markers for insulin resistance: intact proinsulin, adiponectin, retinol-binding protein 4 (RBP4), resistin, and visfatin in patients with PCOS. METHODS: Thirty-five women with clinically confirmed PCOS diagnosis were included in the study [age (mean+/-SD): 24.7+/-4.8 years; body mass index: 27.4+/-6.0 kg/m(2)]. They were randomized to receive either metformin (850 mg twice a day) or rosiglitazone (4 mg once a day). Blood samples for measurement of the HOMA(IR) score, visfatin, RBP4, intact proinsulin, resisitin, and adiponectin were taken at baseline and after 6 months of treatment. RESULTS: Both drugs improved ovulation, and an increase in insulin sensitivity was observed, especially in the rosiglitazone arm. Adiponectin levels increased in both treatment arms (metformin: 8.6+/-3.3 to 16.7+/-7.2 mg/liter, p < 0.001; rosiglitazone: 8.2+/-3.5 to 26.2+/-9.5 mg/liter, p < 0.001), but the increase was more pronounced with rosiglitazone (p < 0.001). While no changes of visfatin concentrations were observed during rosiglitazone therapy (15.4+/-6.9 ng/ml vs 17.4+/-4.8 ng/ml, n.s.), there was an increase in the metformin treatment arm (11.9+/-4.0 to 21.8+/-8.3 ng/ml, p < 0.001). Significant increases demonstrated for RBP4 in both treatment arms were more pronounced in the metformin group (metformin: +66%, rosiglitazone: +33%). All patients were in stage I or II of ss-cell dysfunction and none of them showed increased intact proinsulin levels or changes in resisitin at baseline or end point. CONCLUSIONS: Both drugs slightly improved ovulation in our PCOS patient population during 6 months of therapy, which was accompanied by improved insulin sensitivity and an increase in adiponectin levels. Metformin increased visfatin concentrations. Despite improved insulin resistance, an increase in RBP4 concentration was seen for both drugs. Rosiglitazone seems to be the more favorable drug under these circumstances. However, our results regarding visfatin and RBP4 contradict other reports and further research is required to clarify their value as diagnostic markers for the metabolic syndrome. In this study, adiponectin appeared to be the most promising indicator of both metabolic status and therapeutic success.

Setting a research agenda for perioperative systems design.

Perioperative care may be considered as a system amenable to industrial design approaches. The current care model is disjointed, prone to breakdown by failure of one component, and hostile to personnel. Moving a patient as a person and data set through the flow of perioperative care is not only possible, but it is essential for efficiency and safety. Perioperative systems design integrates the research agenda in technology, safety, informatics, and even telemedicine by putting all the pieces that constitute patient care into a cogent, flexible, and well-managed model.