Exploring complications following cranioplasty after decompressive hemicraniectomy: A retrospective bicenter assessment of autologous, PMMA and CAD implants.

Cranioplasty (CP) after decompressive hemicraniectomy (DHC) is a common neurosurgical procedure with a high complication rate. The best material for the repair of large cranial defects is unclear. The aim of this study was to evaluate different implant materials regarding surgery related complications after CP. Type of materials include the autologous bone flap (ABF), polymethylmethacrylate (PMMA), calcium phosphate reinforced with titanium mesh (CaP-Ti), polyetheretherketone (PEEK) and hydroxyapatite (HA). A retrospective, descriptive, observational bicenter study was performed, medical data of all patients who underwent CP after DHC between January 1st, 2016 and December 31st, 2022 were analyzed. Follow-up was until December 31st, 2023. 139 consecutive patients with a median age of 54 years who received either PMMA (56/139; 40.3%), PEEK (35/139; 25.2%), CaP-Ti (21/139; 15.1%), ABF (25/139; 18.0%) or HA (2/139; 1.4%) cranial implant after DHC were included in the study. Median time from DHC to CP was 117 days and median follow-up period was 43 months. Surgical site infection was the most frequent surgery-related complication (13.7%; 19/139). PEEK implants were mostly affected (28.6%; 10/35), followed by ABF (20%; 5/25), CaP-Ti implants (9.5%; 2/21) and PMMA implants (1.7%, 1/56). Explantation was necessary for 9 PEEK implants (25.7%; 9/35), 6 ABFs (24.0%; 6/25), 3 CaP-Ti implants (14.3%; 3/21) and 4 PMMA implants (7.1%; 4/56). Besides infection, a postoperative hematoma was the most common cause. Median surgical time was 106 min, neither longer surgical time nor use of anticoagulation were significantly related to higher infection rates (p = 0.547; p = 0.152 respectively). Ventriculoperitoneal shunt implantation prior to CP was noted in 33.8% (47/139) and not significantly associated with surgical related complications. Perioperative lumbar drainage, due to bulging brain, inserted in 38 patients (27.3%; 38/139) before surgery was protective when it comes to explantation of the implant (p = 0.035). Based on our results, CP is still related to a relatively high number of infections and further complications. Implant material seems to have a high effect on postoperative infections, since surgical time, anticoagulation therapy and hydrocephalus did not show a statistically significant effect on postoperative complications in this study. PEEK implants and ABFs seem to possess higher risk of postoperative infection. More biocompatible implants such as CaP-Ti might be beneficial. Further, prospective studies are necessary to answer this question.

COVID-19 effects on the kidney.

Apart from pulmonary disease, acute kidney injury (AKI) is one of the most frequent and most severe organ complications in severe coronavirus disease 2019 (COVID-19). The SARS-CoV­2 virus has been detected in renal tissue. Patients with chronic kidney disease (CKD) before and on dialysis and specifically renal transplant patients represent a particularly vulnerable population. The increasing number of COVID-19 infected patients with renal involvement led to an evolving interest in the analysis of its pathophysiology, morphology and modes of virus detection in the kidney. Meanwhile, there are ample data from several autopsy and kidney biopsy studies that differ in the quantity of cases as well as in their quality. While the detection of SARS-CoV­2 RNA in the kidney leads to reproducible results, the use of electron microscopy for visualisation of the virus is difficult and currently critically discussed due to various artefacts. The exact contribution of indirect or direct effects on the kidney in COVID-19 are not yet known and are currently the focus of intensive research.

[COVID-19 effects on the kidney]. / COVID-19-Auswirkungen auf die Niere.

Apart from pulmonary disease, acute kidney injury (AKI) is one of the most frequent and most severe organ complications in severe coronavirus disease 2019 (COVID-19). The SARS-CoV­2 virus has been detected in renal tissue. Patients with chronic kidney disease (CKD) before and on dialysis and specifically renal transplant patients represent a particularly vulnerable population. The increasing number of COVID-19 infected patients with renal involvement led to an evolving interest in the analysis of its pathophysiology, morphology and modes of virus detection in the kidney. Meanwhile, there are ample data from several autopsy and kidney biopsy studies that differ in the quantity of cases as well as in their quality. While the detection of SARS-CoV­2 RNA in the kidney leads to reproducible results, the use of electron microscopy for visualisation of the virus is difficult and currently critically discussed due to various artefacts. The exact contribution of indirect or direct effects on the kidney in COVID-19 are not yet known and are currently the focus of intensive research.

Haptic interface for robot-assisted ophthalmic surgery.

Vitreo-retinal surgery is challenging, as delicate structures have to be manipulated. Eliminating tremor caused by human motions when doing micromanipulation can therefore improve the outcome of such an intervention. An eye surgery robot has been built to overcome this problem. The contribution of this paper is the design of a telemanipulation setup for the robotic system. A telemanipulation setup using a haptic device featuring force feedback as a user interface for controlling a hybrid parallel-serial micromanipulator is designed and developed. The position error control scheme is chosen and different control modes are provided. The output forces of the haptic device are analyzed. The system allows the surgeon to perform precise and comfortable micromanipulation. Nevertheless a way to provide more meaningful force feedback still has to be found.

The introduction of a new robot for assistance in ophthalmic surgery.

This paper introduces the design and development of a new robotic system to assist surgeons performing ophthalmic surgeries. The robot itself is very compact and similar to an average human hand in size. Its primary application is intraocular micromanipulation in order to overcome the existing challenges in treatment of diseases like Retinal Vein Occlusion (RVO). The novel hybrid mechanism designed for this robot allows microscale motions and is stable in the presence of vibrations common in operation room (OR). The robotic system can be easily integrated into standard operation rooms and does not require modification of conventional surgical tools. This compact microsurgical system is suitable for mounting on the patient's head and thereby, solves the problem of patient motion. The compatibility of the robotic system with a real world surgical setup was evaluated and confirmed in this work.

No evidence of XMRV infection in immunocompromised patients and HIV-positive individuals from Germany.

BACKGROUND: Xenotropic murine leukaemia virus-related virus (XMRV) has been detected in patients with prostate cancer and chronic fatigue syndrome (CFS). The detection of XMRV in healthy individuals has raised concern about a possible virus transmission by blood products. However, recent studies challenge the association between XMRV and human disease. This study investigated whether or not XMRV is present in patients with altered immune function and individuals at increased risk of blood-borne viral infections in Germany. METHODS: We investigated 503 peripheral blood mononuclear cell (PBMC) samples from 240 patients with iatrogenic immune suppression (71 haematopoietic stem cell recipients, 132 solid organ transplant recipients, 37 others) and 311 PBMC samples from 302 patients with HIV-1 infection for the presence of proviral XMRV by real-time polymerase chain reaction (PCR). RESULTS: All 814 PBMC samples from 542 patients tested negative for XMRV DNA and positive for an internal herpesvirus saimiri (HVS) control. Human genomic DNA was detected in all samples, and 90% of the samples contained >10,000 cell equivalents per XMRV PCR reaction. CONCLUSIONS: Our failure to detect proviral XMRV provides evidence against the presence of XMRV in patients at increased risk of viral infections in Germany.

Efficacy of the non-adenosine analogue A1 adenosine receptor agonist (BR-4935) on cardiovascular function after cardiopulmonary bypass.

BACKGROUND: We tested the hypothesis that pharmacological preconditioning with a newly developed, potent non-adenosine analogue A1AdoR agonist (BR-4935) improves biventricular cardiac and endothelial function after cardiopulmonary bypass. METHODS: Twelve anesthetized dogs underwent cardiopulmonary bypass. Dogs were divided into two groups: group 1 (n = 6) received saline vehicle, group 2 (n = 6) received BR-4935 before cardiopulmonary bypass. Biventricular hemodynamic variables were measured using a combined pressure-volume conductance catheter. Coronary blood flow, ATP content, malondialdehyde and myeloperoxidase levels and vasodilatative responses to acetylcholine and sodium nitroprusside were also determined. RESULTS: Administration of the A1AdoR agonist led to a significantly better recovery of left and right ventricular systolic function after 60 minutes of reperfusion. Although the vasodilatative response to sodium nitroprusside was similar in both groups, acetylcholine resulted in a significantly greater increase in coronary blood flow in the BR-4935 group. In addition, the ATP content was significantly higher in the same group. Furthermore, malondialdehyde and myeloperoxidase levels significantly decreased in the A1AdoR group. CONCLUSION: Pharmacological preconditioning with a new, potent non-adenosine analogue A1AdoR agonist improves biventricular function recovery and endothelial function after hypothermic cardiac arrest.

Detection of herpesvirus DNA in cerebrospinal fluid and correlation with clinical symptoms.

BACKGROUND: Novel PCR techniques can detect minute quantities of herpesvirus DNA in cerebrospinal fluid (CSF). The clinical significance of such findings is not always clear. PATIENTS AND METHODS: (a) Investigation of clinical characteristics of 76 patients with herpesvirus DNA detection in CSF. (b) Screening for herpesvirus DNA in CSF samples of 208 patients without clinical signs of herpesvirus infection. RESULTS: (a) Eleven of 76 herpesvirus-DNA-positive patients did not show symptoms usually associated with the detected virus (HSV-1/2, n = 5; EBV, n = 6). (b) Two of 208 patients without hint for herpesvirus infection had HHV-6 DNA of low concentration in CSF. CONCLUSIONS: The detection of low-level herpesvirus replication in CSF by highly sensitive PCR assays requires critical evaluation.

Long-term surveillance of haematopoietic stem cell recipients with resolved hepatitis B: high risk of viral reactivation even in a recipient with a vaccinated donor.

Reactivation of resolved hepatitis B virus (HBV) infection is increasingly recognized in patients with severe immunosuppression. We monitored seven patients with pretransplant antibodies to hepatitis B surface antigen (anti-HBs) and hepatitis B core antigen (anti-HBc) for HBV reactivation after allogeneic haematopoietic stem cell transplantation (allo-HSCT). Reverse seroconversion (from anti-HBs to HBsAg) was observed in six recipients occurring 12, 14, 16, 22, 31 and 39 months after allo-HSCT, respectively. The only patient without HBV reactivation had the highest pretransplant anti-HBs titre and died after the shortest follow-up period (25 months). A novel HBV surface mutant (D144G/G145E) was isolated from one recipient of stem cells from a donor vaccinated against HBV. Another surface mutant (P142L/G145R) was detected in a recipient from a non-immune donor. Serum ALT elevation was measured in only two of the six patients with viral reactivation, followed by spontaneous clearance of HBsAg in one of them. Antiviral treatment reduced viral load in five patients, but the emergence of YMDD motif polymerase mutations resulted in lamivudine resistance in two patients. In conclusion, the risk of reactivation of a resolved HBV infection is close to 100% in allogeneic stem cell recipients and vaccination of the donor does not always warrant reliable protection.

Clinical benefit of enzyme replacement therapy in Fabry disease.

Enzyme replacement therapy (ERT) with recombinant human alpha-galactosidase A (r-halphaGalA) enhances microvascular globotriaosylceramide clearance and improves clinical symptoms in patients with Fabry disease. We evaluated whether these effects are translated into a long-term benefit of kidney and heart function. We did a single center, prospective, open label study in 26 patients with Fabry disease (one early death, follow-up in 25 patients). r-Alpha-GalA was administered in a dosage of 1 mg/kg body weight every second week. The effect of therapy on clinical end points (death, cardiac and cerebrovascular event, renal failure), cardiac and renal function monitored by Doppler echocardiography, 99Tc-GFR, and proteinuria was investigated. After a mean treatment time of 23 +/- 8 months, nine patients experienced 12 end points, including two deaths. All end points occurred in patients with impaired renal function (n = 16; GFR 71 +/- 17 ml/min/1.73 m2). Despite ERT, renal function deteriorated to 60 +/- 23 ml/min/1.73 m2 (P = 0.04) and left ventricular posterior wall thickness (PWT) did not change (14.0 +/- 2.1 vs 13.4 +/- 2.3 mm). In contrast, patients without impairment of renal function (n = 9) had a more favorable outcome (no clinical events; GFR 115 +/- 18 vs 102 +/- 14 ml/min/1.73 m2, NS; PWT 11.7 +/- 1 and 10.7+/-0.7 mm, P = 0.04). Proteinuria remained unchanged (1.34 +/- 0.94 vs 1.01 +/- 0.97 g/day, n = 10). Patients with impaired renal function have a less favorable outcome and may develop cardiovascular and renal end points despite ERT.

Morbus Fabry of the heart. Why should cardiologists care?

Fabry Disease is an X-linked lysosomal storage disorder leading to the accumulation of glycosphingolipids, mainly globotriaosylceramides in all tissues and solid organs of the body. The disease was described by Johannes Fabry and William Anderson coevally in 1898. Beside the involvement of the central nervous system, peripheral nerves, kidneys, skin and endovascular endothelium, the heart plays a major role in the disease. Left ventricular hypertrophy is one hallmark initially presenting with preserved ventricular function. However, with progression of the disease patients die due to heart failure. Though angina is often reported, the incidence of epicardial coronary stenosis is not a dominant feature, if at all small vessel disease can occur. In respect of arrhythmias a broad spectrum can be seen including shortened or prolonged PR-intervals, AV blocks of different degrees and sometimes malignant ventricular arrhythmias. In the past, women were considered to be carriers of the disease but hardly to develop clinical symptoms. In recent years there is evidence that female carriers may more often be affected with severe symptoms. In addition, a group of Fabry patients displaying mainly cardiac involvement were described as having a cardiac variant of the disease. This implied the hypothesis that some of those patients with unexplained myocardial hypertrophy do suffer from Fabry disease. Since 2002 enzyme replacement therapy is available and there is first evidence for its efficacy to reduce hypertrophy and increase myocardial function. If this is associated with a prognostic improvement has to be determined in future studies.

Towards robotic heart surgery: introduction of autonomous procedures into an experimental surgical telemanipulator system.

The introduction of telemanipulator systems into cardiac surgery enabled the heart surgeon to perform minimally invasive procedures with high precision and stereoscopic view. For further improvement and especially for inclusion of autonomous action sequences, implementation of force-feedback is necessary. The aim of our study was to provide a robotic scenario giving the surgeon an impression very similar to open procedures (high immersion) and to enable autonomous surgical knot tying with delicate suture material. In this experimental set-up the feasibility of autonomous surgical knot tying is demonstrated for the first time using stereoscopic view and force feedback.

Reactivation of resolved hepatitis B virus infection after allogeneic haematopoietic stem cell transplantation.

Hepatitis B virus (HBV) reactivation after allogeneic haematopoietic stem cell transplantation (allo-HSCT) is well known in HBsAg-positive carriers but has only occasionally been reported in patients with resolved HBV infection. We investigated six allo-HSCT recipients with pretransplant anti-HBs and anti-HBc antibodies for serologic markers of HBV infection and for the presence of HBV-DNA in serum. Reverse seroconversion, that is, reappearance of HBsAg after a gradual loss of anti-HBs, but no severe liver damage was observed in three patients at 14, 22 and 12 months after HSCT, respectively. There was an increase in HBV-DNA concentration prior to reverse seroconversion. One patient was repeatedly HBV-DNA positive (10(2)-10(3) copies/ml) without reverse seroconversion. Sequencing of the HBsAg and precore region derived from the four HBV-DNA-positive patients showed no relevant mutations. In conclusion, this study demonstrated a high risk (50%) of reverse seroconversion in allo-HSCT recipients with resolved HBV infection. A highly sensitive HBV-DNA assay (TaqMan-PCR) allowed early identification of the individual patients at risk.

Intensive care after minimally invasive and conventional coronary surgery: a prospective comparison.

OBJECTIVE: The purpose of this study was to compare the intensive care course of patients after minimally invasive coronary surgery to conventional coronary artery bypass grafting. DESIGN: Prospective observational study. SETTING: Intensive care unit of a university hospital. PATIENTS AND PARTICIPANTS: One hundred and five patients with two-vessel disease consecutively scheduled for elective coronary bypass surgery were enrolled. INTERVENTIONS: Two techniques of revascularization were performed: the Octopus procedure via median sternotomy without cardiopulmonary bypass (n = 52) and conventional coronary artery bypass grafting CABG (n = 53). MEASUREMENTS AND RESULTS: Three major categories describing the patients' postoperative course were defined: (1) clinical and laboratory findings, i.e., transfusion rate, catecholamine support, duration of ventilation, Simplified Acute Physiology Score II (SAPS II), serum levels of cardiac enzymes and lactic acid; (2) postoperative complications, i.e., incidence of myocardial infarction (MI), atrial fibrillation (AF), and neurological deficits; (3) this category was defined as "the extent of care" as represented by the Therapeutic Intervention Scoring System (TISS), and the length of stay in the ICU and in the hospital. In the Octopus group significantly lower figures were noted for duration of ventilation [6.1(5.5/9.5) vs 10.2(8.2/11.8) h], cardiac enzymes (CK-MB-Mass [5.1(2.0/8.3) vs 31.3(21.4/39.3) ng/ml], and lactic acid [2.0(1.5/3.3) vs 3.2(2.2/6.5) mmol/l]), incidence of AF (2/52 vs 9/53), and neurological deficits (0/52 vs 4/53), TISS score [72(44/83) vs 84(73/93)], LOS in the ICU [2(1/2) vs 2(2/2) days], and in the hospital [6(5/9) vs 9(8/12) days]. Catecholamine support, SAPS II scores, and incidence of MI of each group did not differ significantly. CONCLUSIONS: Off-pump coronary surgery via the Octopus technique was superior to conventional CABG regarding the course of patients in the early postoperative period. This implies benefits for the patients and the entire healthcare system.