The evaluation of a novel haptic-enabled virtual reality approach for computer-aided cephalometry.

BACKGROUND AND OBJECTIVE: In oral and maxillofacial surgery, conventional radiographic cephalometry is one of the standard auxiliary tools for diagnosis and surgical planning. While contemporary computer-assisted cephalometric systems and methodologies support cephalometric analysis, they tend neither to be practical nor intuitive for practitioners. This is particularly the case for 3D methods since the associated landmarking process is difficult and time consuming. In addition to this, there are no 3D cephalometry norms or standards defined; therefore new landmark selection methods are required which will help facilitate their establishment. This paper presents and evaluates a novel haptic-enabled landmarking approach to overcome some of the difficulties and disadvantages of the current landmarking processes used in 2D and 3D cephalometry. METHOD: In order to evaluate this new system's feasibility and performance, 21 dental surgeons (comprising 7 Novices, 7 Semi-experts and 7 Experts) performed a range of case studies using a haptic-enabled 2D, 2½D and 3D digital cephalometric analyses. RESULTS: The results compared the 2D, 2½D and 3D cephalometric values, errors and standard deviations for each case study and associated group of participants and revealed that 3D cephalometry significantly reduced landmarking errors and variability compared to 2D methods. CONCLUSIONS: Through enhancing the process by providing a sense of touch, the haptic-enabled 3D digital cephalometric approach was found to be feasible and more intuitive than its counterparts as well effective at reducing errors, the variability of the measurements taken and associated task completion times.

[Bone liposclerosing myxofibrous tumor. Case presentation and literature review]. / Tumor fibromixoma lipoesclerosante óseo. Presentación de un caso y revisión de la literature.

The bone liposclerosing myxofibrous tumor (LSMFT) was initially described by Ragsdale in 1986 as a polymorphic fibroosseous bone lesion with a mix of histologic elements that include lipoma, fibroxanthoma, myxoma, myxofibroma, fat necrosis, ischemic ossification, areas of fibrous dysplasia, and infrequent presence of cartilage or cystic changes. The most frequently reported location is the intertrochanteric area of the femur. Radiologically it is a lytic, geographic lesion, with well-defined margins and usually sclerotic. In some cases findings include mineralization inside the lesion or a certain degree of expansion to the contour. The close relationship between LSMFT and fibrous dysplasia has been described based on the histologic characteristics and the presence of the Gsα mutation. Another hypothesis of the etiology of the lesion is the reaction of fibrous dysplasia to stress.

Disección aórtica tipo A: Resultados operatorios y seguimiento a mediano plazo / Surgical results among 100 patients with type A aortic dissection: Retrospective review

Background: Tipe A aortic dissection involves the ascending aorta and has high mortality rates without surgical treatment. Aim: To report the results of surgical treatment of type A aortic dissection. Material and Methods: Retrospective review of medical records of 100 patients aged 17 to 78 years (73 percent males) operated between January 2000 and August 2008, for type A aortic dissection. Follow up was performed with telephone interviews and review of national death records. Results: Eighty three percent of patients had an acute dissection. Operative mortality was 27 and 20 percent for patients with acute and chronic dissection, respectively. Mortality was 50 percent among patients aged 70 years or more, compared with 21 percent among their younger counterparts, The most common complication was bleeding that required a new surgical procedure in 18 percent of patients. Actuarial survival was 70 percent at five years. Cardiovascular problems caused the death of two of the nine patients that died during follow up. Conclusions: Surgical mortality among patients with type A aortic dissection was higher among patients with acute episodes and those aged 70 years or more.

Limited role for IVUS in the endovascular repair of aortoiliac aneurysms.

BACKGROUND: To determine the need for routine versus selective intraoperative IVUS during endovascular aortoiliac aneurysm (AIA) repair. METHODS: One-hundred and eighty-eight endovascular AIA repairs performed over a 5-year period were reviewed and included in the study. Surgeon-made aorto-uni-femoral grafts (n=78) and industry-made bifurcated or tube grafts (n=110) were used. In the initial 51 cases IVUS was routinely performed. In the latter 137 cases IVUS was used selectively. In this group graft deformities suspected on completion angiography or pullback pressure measurements were treated with balloon dilatation and stenting. IVUS was then performed only in the presence of a persistent pressure gradient or inconclusive angiographic findings. RESULTS: In the initial 51 cases IVUS revealed 20 lesions of which 8 were not initially detected angiographically and which required further treatment. In the latter 137 cases IVUS was necessary in only 1 case, and guided the treatment of an angiographically undetectable lesion. There have been no late episodes of graft compression, kinking, or thrombosis in the selective IVUS group. CONCLUSIONS: The use of pullback pressure measurements with a low threshold for angioplasty and stenting, especially in unsupported grafts, followed by the selective use of IVUS decreases the overall requirement for IVUS and its associated costs.

Pancreatic insufficiency in patients with chronic graft-versus-host disease.

Diarrhea is a difficult diagnostic problem in patients with chronic graft-versus-host disease (cGVHD) because there are many causes of it. Although intestinal involvement has been reported in early studies of untreated cGVHD, this is now a very rare presentation of the disease. In addition to other etiologies, pancreatic insufficiency should also be considered in patients with cGVHD who demonstrate malabsorption. The pathogenesis of pancreatic insufficiency in these patients is unknown. Pancreatic enzyme supplements can be very effective in treating this rare condition.

Leishmania infantum-specific IgG, IgG1 and IgG2 antibody responses in healthy and ill dogs from endemic areas. Evolution in the course of infection and after treatment.

The expression of IgG, IgG1 and IgG2 specific antibodies for Leishmania infantum was studied in five groups of dogs in Catalonia (Spain): I, 99 asymptomatic dogs (infected and uninfected) from a highly endemic area for leishmaniosis; II, 139 untreated dogs with clinically patent leishmaniosis; III, 11 naturally infected asymptomatic dogs monitored for up to 5 years since they were found seropositive to Leishmania antigen and without treatment; IV, 25 naturally infected dogs with clinically patent leishmaniosis and treated with either meglumine antimoniate and allopurinol or allopurinol alone and V, six experimentally infected dogs, treated with meglumine antimoniate and controlled for 5 years. The levels (ELISA units) of IgG, IgG1 and IgG2 in asymptomatic dogs (group I) were very variable (24+/-33, 32+/-31 and 26+/-31, respectively), and, as expected, lower than in ill dogs (group II) (168+/-34, 84+/-71 and 172+/-31, respectively). In both groups, the correlation between IgG and IgG2 levels (r=0.95, P<0.001 in group I and r=0.63, P<0.001 in group II) was higher than between IgG and IgG1 levels (r=0.01, P>0.05 in group I and r=0.31, P<0.001 in group II). In group III, IgG and IgG2 expression increased during infection, while IgG1 expression remained the same. In dogs of group IV, IgG levels after 1 year of treatment decreased more in responsive (mean values, 163+/-42 before treatment (b.t.) and 100+/-36 after treatment (a.t.)) than in unresponsive dogs (158+/-29 b.t. and 124+/-51 a.t.), especially for IgG1 (94+/-89 b.t. and 20+/-21 a.t. in responsive dogs and 35+/-25 b.t. and 22+/-13 a.t. in unresponsive dogs) rather than for IgG2 (156+/-16 b.t. and 114+/-45 a.t. in responsive and 151+/-11 b.t. and 125+/-36 a.t. in unresponsive dogs). Similar results were observed in the evolution of experimentally infected animals after consecutive and specific treatments. Overall results show the great variation in Leishmania-specific IgG1 expression in asymptomatic and symptomatic dogs, their lack of correlation with that of IgG2 and chemotherapy is more effective in dogs with initially high expression of IgG1.

Prosthetic patch remnants to treat infected arterial grafts.

PURPOSE: Our previous experience with the traditional management of infected prosthetic arterial grafts, which included graft excision and vein patch repair of the involved artery, was complicated by a high incidence of vein patch rupture. This study assessed the treatment of infected prosthetic grafts with subtotal graft excision and oversewing of small graft remnants. METHODS: During the last 20 years, we treated 53 wounds involving 45 infected prosthetic grafts in 42 patients by means of subtotal graft excision and oversewing of a residual 2- to 3-mm graft remnant (patch) at an intact arterial anastomosis. This technique was selectively used to maintain patency of small-diameter arteries (41 common femoral, five deep femoral, three axillary, two iliac, and two popliteal), which were critical for limb salvage or amputation healing. This strategy avoided difficult dissection of the underlying artery in scarred wounds and obviated the placement of a new patch in an infected field. Graft remnants were polytetrafluoroethylene in 51 cases and Dacron in two cases. Of the 45 grafts, 31 were occluded and 14 were patent. All infected tissue was widely debrided, wet-to-dry dressing changes were performed three times daily, and appropriate intravenous antibiotics were administered for at least 1 week. Secondary bypass grafting procedures were performed as needed to achieve limb salvage. The follow-up period in surviving patients averaged 32 months (range, 1 to 218 months). RESULTS: No complications were directly attributable to prosthetic patch remnants in 92% of cases (49 of 53 cases). Six of 42 patients (14%) died during hospitalization (three of cardiac complications and three of sepsis with multiple organ failure). Two infected pseudoaneurysms developed 8 and 34 months after surgery, and two wounds failed to heal. Sixteen secondary bypass grafting procedures were necessary to achieve limb salvage. Patch oversewing led to limb salvage without the need for secondary revascularization in 26 other cases and to the successful healing of 10 amputated limbs when secondary revascularization was not possible. CONCLUSION: Prosthetic patch remnants are a useful adjunct that simplify management of infected prosthetic grafts, are associated with a low incidence of wound complications, and help maintain patency of essential collaterals to achieve limb salvage or heal an amputation.

Midterm experience with the endovascular treatment of isolated iliac aneurysms.

PURPOSE: This report describes our 5-year experience with the endovascular repair of isolated iliac aneurysms and pseudoaneurysms. METHODS: Between June 1993 and July 1998, 40 isolated iliac aneurysms and pseudoaneurysms were treated with endovascular grafts in 39 patients. Thirty-seven aneurysms were treated with endovascular grafts composed of polytetrafluoroethylene grafts and balloon expandable stents, and the other three underwent repair with a polycarbonate urethane endoluminal graft. RESULTS: All the patients underwent initially successful endovascular treatment of isolated iliac aneurysms and pseudoaneurysms and were followed from 1 to 51 months (mean, 18 months). The 4-year primary patency rate was 94.5% +/- 10%. The perioperative complications included one episode of distal embolization, an episode of colonic ischemia, five episodes of kinking or compression of the endovascular graft, and one early postoperative graft thrombosis. There was only one perioperative death in a patient whose aneurysm ruptured in the operating room just before endovascular repair. The median postoperative length of hospital stay was 3.0 +/- 1.3 days in this group of patients at moderate and high risk. The long-term complications included one graft thrombosis and two endoleaks. One small endoleak was followed until the patient died of unrelated causes, and the other one led to aneurysm rupture in the only patient temporarily lost to follow-up examination. This patient successfully underwent treatment in the standard open surgical fashion. To date, all the other aneurysms have remained stable or have decreased in size during the follow-up examinations with duplex or contrast-enhanced computed tomographic scans. CONCLUSION: Endovascular repair of iliac aneurysms and pseudoaneurysms is a safe and effective technique with good midterm results in patients at standard and high risk. These grafts are particularly beneficial for patients with medical, surgical, or anatomic contraindications for open surgical repair.

Serological and parasitological follow-up in dogs experimentally infected with Leishmania infantum and treated with meglumine antimoniate.

Six healthy beagle dogs were infected with Leishmania infantum (MCAN/ES/92/BCN-83/MON-1) by intravenous inoculation of 5 x 10(7) promastigotes and two others were used as controls. When animals showed clinical signs of disease at 29, 37, 41 and 45 weeks post-infection (p.i.), they were treated with meglumine antimoniate (20.4 mg Sb/kg/12 h) subcutaneously for two periods of 10 days each. Sera were tested periodically for Leishmania antibodies by Dot-ELISA, ELISA and Western blot (WB). Aspirates of popliteal lymph node (PLN), peripheral blood sample (PB) and healthy skin were cultured in NNN and Schneider's medium. PLNs were positive between 8 and 20 weeks p.i. and in one animal PB was positive 6 weeks p.i. Samples of healthy skin, obtained before treatment, were also positive. Dot-ELISA and ELISA detected specific antibodies at an early stage between 4 and 12 weeks p.i and surpassed the cut-off between 16-24 weeks p.i., while the WB was positive between 10-19 weeks p.i. The pattern of bands revealed during the first stages of infection was variable and only in two cases did the positivity start with bands of low molecular weight (12-14 kD); the number of bands increased until 15-24 weeks p.i., after which sera revealed a complete pattern of bands, from 12 to 85 kD, in the antigen of Leishmania. After treatment the clinical improvement of the animals was accompanied by a decrease in antibody titers (Dot-ELISA and ELISA) although the parasites remained in the PLN. This was reflected in the WB by a decrease in the intensity of bands, especially those in the region of 12-30 kD. A new increase in the antibody levels between 3 and 5 months after terminating the therapy was detected in the WB by a restoration of the initial complete pattern of bands.

Chronic pure red cell aplasia caused by parvovirus B19 in AIDS: use of intravenous immunoglobulin--a report of eight patients.

The optimal management of chronic pure red cell aplasia caused by parvovirus B19 (B19-PRCA) in patients with AIDS is unclear. Our purpose was to determine the effects of intravenous immunoglobulin (IVIg) in the treatment of B19-PRCA in patients with AIDS. The patients were eight adults with AIDS admitted during the period 1993-1997. A diagnosis of B19-PRCA was made if all the following criteria were met: 1. Bone marrow biopsy finding of pure red cell aplasia; 2. Detection of parvovirus B19 DNA in serum; and 3. No alternative explanation for PRCA. Initial (induction) therapy was with IVIg 1 g/kg daily for 1-2 days. Relapses were treated with IVIg 1 g/kg for 2 days. Maintenance therapy with IVIg 0.4-1.0 g/kg q 4 weeks was given to those patients who developed a second or subsequent relapse. The patients were followed for a mean of 27 months (range 8-38 months). All patients responded to initial therapy with IVIg. Six patients with CD4 counts < 80 cells/mm3 relapsed. The response was short lived in two patients with a CD4 count < 80 cells/mm3 who were given a single infusion of IVIg 1 g/kg as initial therapy. Four patients were given regular maintenance IVIg therapy following a second or subsequent relapse and remain in remission. Two patients whose CD4 counts were > 300 cells/mm3 remain in continuous unmaintained remission from B19-PRCA for over 8 and 11 months, respectively, following induction therapy with IVIg. AIDS patients with B19-PRCA respond well to therapy with IVIg 2 g/kg given over 2 days. Most patients with CD4 counts of < or = 80 cells/mm3 suffer relapse within six months necessitating retreatment with IVIg; maintenance therapy with IVIg 0.4 g/kg q 4 weeks is effective in preventing relapse of B19-PRCA, and may be cost effective. Routine maintenance therapy is probably not indicated in patients with CD4 counts over 300 cells/mm3. Prospective studies are needed to confirm these findings.

Thrombocytopathia and light-chain proteinuria in a dog naturally infected with Ehrlichia canis.

A 6-year-old dog was presented for evaluation of recurrent epistaxis. Platelet counts, biochemical tests, and coagulation tests were within the normal range, but a mucosal bleeding time was prolonged; there was hyperproteinemia and a monoclonal gammopathy. Heterogeneity of light chains appeared in urine, however, thus suggesting that the gammopathy was polyclonal. Platelet aggregation tests showed decreased responsiveness to collagen. An Ehrlichia canis indirect fluorescent-antibody titer was positive (1:40). Treatment with tetracycline, melphalan, and prednisone resulted in a rapid clinical improvement that persisted for at least 3 years.

Incidence of lower extremity deep vein thrombosis in neurosurgical patients.

In 100 patients who underwent major cranial or spinal operations, the incidence of lower extremity deep vein thrombosis was 29%. Of importance was the presence of known risk factors, particularly leg weakness and a long operation. The subject of deep vein thrombosis and its complications in neurosurgical disorders is reviewed and its prophylaxis is discussed. The administration of low dose heparin based on an epidemiological analysis of the risks involved would seem to be an effective method of prophylaxis.

Malignant choroid plexus papilloma with extraneural metastasis. Case report.

The authors describe and discuss a case of malignant choroid plexus papilloma originating in the lateral ventricle of an 11-month-old child. Unusual features include a long survival time of 9 years and the presence of an extraneural malignant deposit, probably metastatic in origin.