The Role of Indocyanine Green Fluorescence Angiography in Complex Abdominal Wall Reconstruction: A Scoping Review of the Literature.

BACKGROUND: Indocyanine green fluorescence angiography (ICGFA) is a technique for assessing vascularity and perfusion which has multiple proven applications across a variety of surgical procedures. Studies have been performed assessing its potential role in evaluating skin flap viability in complex abdominal wall reconstruction (CAWR) in order to avoid postoperative surgical site occurrences (SSO). OBJECTIVES: This scoping review was intended to summarise the literature concerning ICGFA in CAWR in order to facilitate future evidence-based guidelines for its use. ELIGIBILITY CRITERIA: Inclusion - cohort studies, randomised controlled trials, case series, case reports and ventral midline hernias only. Exclusion - patients aged under 18 years and non-human test subjects. SOURCES OF EVIDENCE: PubMed, MEDLINE®, Cochrane, Embase and OpenGrey RESULTS: A total of 3416 unique titles were yielded from our search of which 9 met our inclusion criteria: 3 case reports, 1 retrospective case series, 1 prospective case series, 3 non-blinded, non-randomised retrospective case-controlled studies and 1 prospective, double-blinded randomised controlled study. The included studies varied considerably in size and method however the consensus appeared to support ICGFA as being a safe and feasible means of assessing tissue flap vascularity in CAWR. The studies returned contrasting results regarding the impact of ICGFA in predicting and avoiding SSOs however there were insufficient numbers of studies for a meta-analysis. CONCLUSIONS: We identify three case reports and four lower quality studies suggesting a possible application for ICGFA in CAWR and two higher quality studies showing no overall benefit. Evidence-based guidelines on the role of ICGFA in CAWR will require the assessment of further studies.

The role of teleconsultation in the management of suspected skin malignancy in plastic surgery during COVID-19 outbreak: A single centre experience.

The COVID-19 pandemic has had a profound impact on the provision of skin cancer treatment in the UK. To preserve the service, the department transformed the outpatient skin cancer clinic into teleclinic service. This study examines the safety and efficacy of a teleclinic consultation, in comparison to a face-to-face consultation. We assessed efficacy in terms of accuracy of the clinical diagnosis in comparison to the histopathological result and whether treatment was designated the appropriate clinical priority/urgency. A total of 120 lesions in 98 patients were assessed, 55 patients in the face-to-face clinic cohort, and 43 patients in the teleclinic cohort. Diagnostic accuracy was better in face-to-face clinic compared to teleclinic; 85.0% and 63.6% respectively (χ2 (1, N = 120) = 7.35, p = 0.0067). The accuracy of listing patients on the correct pathway was slightly higher for teleclinic patients. Of the teleclinic patients listed through the urgent pathway, 45.7% justified their urgent status, compared with 37.5% of those listed urgent in face-to-face clinic (p = 0.67). For those listed as routine, 100% of teleclinic patients were listed appropriately whereas the accuracy was 96.8% for the face-to-face clinic counterpart. In conclusion, despite teleclinic having slightly reduced diagnostic accuracy, teleclinics show comparable accuracy in listing patients to urgent or routine skin cancer pathways. It offers convenience to patients in addition to reducing time to treatment and cost effectiveness. The lessons learned in the pandemic can be applied to the post-COVID healthcare environment.

Sensory neuron death after upper limb nerve injury and protective effect of repair: clinical evaluation using volumetric magnetic resonance imaging of dorsal root Ganglia.

BACKGROUND: Extensive death of sensory neurons after nerve trauma depletes the number of regenerating neurons, contributing to inadequate cutaneous innervation density and poor sensory recovery. Experimentally proven neuroprotective neoadjuvant drugs require noninvasive in vivo measures of neuron death to permit clinical trials. In animal models of nerve transection, magnetic resonance imaging (MRI) proved a valid tool for quantifying sensory neuron loss within dorsal root ganglia (DRG) by measuring consequent proportional shrinkage of respective ganglia. OBJECTIVE: This system is investigated for clinical application after upper limb nerve injury and microsurgical nerve repair. METHODS: A 3-T clinical magnet was used to image and measure volume (Cavalieri principle) of C7-T1 DRG in uninjured volunteers (controls, n = 14), hand amputees (unrepaired nerve injury, n = 5), and early nerve repair patients (median and ulnar nerves transected, microsurgical nerve repair within 24 hours, n = 4). RESULTS: MRI was well tolerated. Volumetric analysis was feasible in 74% of patients. A mean 14% volume reduction was found in amputees' C7 and C8 DRG (P < .001 vs controls). Volume loss was lower in median and ulnar nerve repair patients (mean 3% volume loss, P < .01 vs amputees), and varied among patients. T1 DRG volume remained unaffected. CONCLUSION: MRI provides noninvasive in vivo assessment of DRG volume as a proxy clinical measure of sensory neuron death. The significant decrease found after unrepaired nerve injury provides indirect clinical evidence of axotomy-induced neuronal death. This loss was less after nerve repair, indicating a neuroprotective benefit of early repair. Volumetric MRI has potential diagnostic applications and is a quantitative tool for clinical trials of neuroprotective therapies.

Sensory neurons of the human brachial plexus: a quantitative study employing optical fractionation and in vivo volumetric magnetic resonance imaging.

BACKGROUND: Extensive neuron death following peripheral nerve trauma is implicated in poor sensory recovery. Translational research for experimentally proven neuroprotective drugs requires knowledge of the numbers and distribution of sensory neurons in the human upper limb and a novel noninvasive clinical measure of neuron loss. OBJECTIVE: To compare optical fractionation and volumetric magnetic resonance imaging (MRI) of dorsal root ganglia (DRG) in histological quantification and objective clinical assessment of human brachial plexus sensory neurons. METHODS: Bilateral C5-T1 DRG were harvested from 5 human cadavers for stereological volume measurement and sensory neuron counts (optical fractionator). MRI scans were obtained from 14 healthy volunteers for volumetric analysis of C5-T1 DRG. RESULTS: The brachial plexus is innervated by 425,409 (standard deviation 15,596) sensory neurons with a significant difference in neuron counts and DRG volume between segmental levels (P < .001), with C7 ganglion containing the most. DRG volume correlated with neuron counts (r = 0.75, P < .001). Vertebral artery pulsation hindered C5 and 6 imaging, yet high-resolution MRI of C7, C8, and T1 DRG permitted unbiased volume measurement. In accord with histological analysis, MRI confirmed a significant difference between C7, C8, and T1 DRG volume (P < .001), interindividual variability (CV = 15.3%), and sex differences (P = .04). Slight right-left sided disparity in neuron counts (2.5%, P = .04) was possibly related to hand dominance, but no significant volume disparity existed. CONCLUSION: Neuron counts for the human brachial plexus are presented. These correlate with histological DRG volumes and concur with volumetric MRI results in human volunteers. Volumetric MRI of C7-T1 DRG is a legitimate noninvasive proxy measure of sensory neurons for clinical study.

Volumetric magnetic resonance imaging of dorsal root ganglia for the objective quantitative assessment of neuron death after peripheral nerve injury.

Prevention of neuron death after peripheral nerve injury is vital to regaining adequate cutaneous innervation density and quality of sensation, and while experimentally proven neuroprotective therapies exist, there lacks suitable clinical outcome measures for translational research. Axotomized dorsal root ganglia (DRG) histologically exhibit volume reduction in proportion to the amount of neuronal death within them. Hence, this study evaluated the validity of using magnetic resonance imaging (MRI) to quantify DRG volume as a proxy measure of cell death. A high-resolution 3D MRI sequence was developed for volumetric quantification of the L4 DRG in the rat sciatic nerve model. An unoperated "control" group (n=4), and a "nerve transection" group (n=6), 4 weeks after axotomy, were scanned. Accuracy and validity of the technique were evaluated by comparison with morphological quantification of DRG volume and stereological counts of surviving neurons (optical fractionator). The technique was precise (coefficient of variation=4.3%), highly repeatable (9% variability), and sensitive (mean 15.0% volume reduction in axotomized ganglia detected with statistical significance: p<0.01). MRI showed strong and highly significant correlation with morphological measures of DRG volume loss (r=0.90, p<0.001), which in turn correlated well with neuron loss (r=0.75, p<0.05). MRI similarly exhibited direct correlation with neuron loss (r=0.67, p<0.05) with consistent agreement. MRI volumetric quantification of DRG is therefore a valid in vivo measure of neuron loss. As a non-invasive, objective measure of neuronal death after nerve trauma this technique has potential as a diagnostic modality and a quantitative tool for clinical studies of neuroprotective agents.