Dose reduction in CT while maintaining diagnostic confidence: diagnostic reference levels at routine head, chest, and abdominal CT--IAEA-coordinated research project

PURPOSE: To measure radiation doses for computed tomography (CT) of the head, chest, and abdomen and compare them with the diagnostic reference levels, as part of the International Atomic Energy Agency Research coordination project. MATERIALS AND METHODS: The local ethics committees of all participating institutions approved the study protocol. Written informed consent was obtained from all patients. All scanners were helical single-section or multi-detector row CT systems. Six hundred thirty-three patients undergoing head (n = 97), chest (n = 243), or abdominal (n = 293) CT were included. Collected data included patient height, weight, sex, and age; tube voltage and tube current-time product settings; pitch; section thickness; number of sections; weighted or volumetric CT dose index; and dose-length product (DLP). The effective dose was also estimated and served as collective dose estimation data. RESULTS: Mean volumetric CT dose index and DLP values were below the European diagnostic reference levels: 39 mGy and 544 mGy . cm, respectively, at head CT; 9.3 mGy and 348 mGy . cm, respectively, at chest CT; and 10.4 mGy and 549 mGy . cm, respectively, at abdominal CT. Estimated effective doses were 1.2, 5.9, and 8.2 mSv, respectively. CONCLUSION: Comparison of CT results with diagnostic reference levels revealed the need for revisions, partly because the newer scanners have improved technology that facilitates lower patient doses.     

Surgical management of giant intracranial aneurysms

OBJECTIVES: The natural history of giant intracranial aneurysms is generally morbid. Mortality and morbidity associated with giant aneurysms is also higher than for smaller aneurysms. This study was carried out to assess the demographic profile, presenting features, complications, and outcome after surgical treatment of giant intracranial aneurysms. PATIENTS AND METHODS: A retrospective review of the medical records of all patients with giant intracranial aneurysms treated in the Department of Neurosurgery, Neurosciences Centre, All India Institute of Medical Sciences, New Delhi, from January 1995 through June 2007 was performed. The demographic profiles, presenting features, radiological findings, surgical treatments, and outcomes were assessed. RESULTS: A total of 1412 patients harboring 1675 aneurysms were treated. Out of these, 222 patients had 229 (13.7%) giant aneurysms, and of those, 181 aneurysms in 177 patients were managed surgically while 48 were treated with endovascular therapy. In the patients treated with surgery, common clinical presentations included subarachnoid hemorrhage (SAH) in 110 (62%) cases followed by mass effect in 57 (32%) cases. In patients who presented with SAH, the Hunt and Hess SAH grading was: grade I in 43 (39%), grade II in 40 (36%), grade III in 23 (21%), grade IV in two (2%), and grade V in 2 (2%) patients. One hundred and seven aneurysms (in 103 patients) were treated using direct surgical clipping. Forty-six patients with good collateral circulation were treated by gradual occlusion and ligation of the internal carotid artery (ICA) in the neck with a Silverstone clamp. Another nine patients with good collateral circulation, but persisting symptoms after ICA ligation, required trapping for obliteration of the aneurysm. Eleven patients with poor collateral circulation required extracranial-intracranial (EC-IC) bypass before proximal ICA ligation. A post-operative digital subtraction angiography (DSA) was performed in 118 patients and revealed well-obliterated aneurysm in 106 patients. The total treatment mortality rate was 9%. In the last 5 years, 117 patients were operated on with four operative deaths. Overall, the outcome was excellent in 131 (74.0%), good in 22 (12.4%), and poor in eight (4.5%) cases. CONCLUSIONS: It is concluded that 14% of all intracranial aneurysms are giant. The most common clinical presentation is SAH followed by features of an intracranial mass lesion. The cavernous ICA is the most common portion of the ICA affected. Direct surgical clipping is a safe and effective method of treatment and should be considered the first line of treatment whenever possible. With proper case selection, optimal radiological evaluation, and appropriate surgical strategy, it is possible to achieve a favorable outcome in almost 90% of the cases.     

CSF1R mutation presenting as dementia with Lewy bodies

Hereditary diffuse leukoencephalopathy with spheroids (HDLS) is an adult-onset autosomal dominant leukoencephalopathy resulting from mutations affecting the tyrosine kinase domain of the colony stimulating factor receptor 1 protein (encoded by CSF1R). The clinical phenotypes reported with CSF1R mutations are variable. We present a case of a patient with a pathogenic variant in the CSF1R gene with clinical and imaging features suggestive of Dementia with Lewy Bodies (DLB). This case expands the known clinical presentations associated with CSF1R mutations.     

A novel scheme for the validation of an automated classification method for epileptic spikes by comparison with multiple observers

Objective

To validate the application of an automated neuronal spike classification algorithm, Wave_clus (WC), on interictal epileptiform discharges (IED) obtained from human intracranial EEG (icEEG) data.

Effectiveness of Human Amnion as a Graft Material in Lower Anterior Ridge Vestibuloplasty: A Clinical Study

Objective  

The aim of this study is to evaluate the clinical use of amnion as a biodegradable graft material for lower anterior ridge vestibuloplasty.     

Modified Presurgical Nasoalveolar Molding in the Infants with Complete Unilateral Cleft Lip and Palate: A Stepwise Approach

Presurgical orthopedics in one or the other form has been an important part of the multidisciplinary approach towards the better cleft care. Presurgical nasoalveolar molding (PNAM) was described as a modified approach to the conventional form of orthopedics. PNAM not only reduces the severity of the alveolar defect before surgery, it also reduces the nasal deformity bringing it near to the normal. Nonsurgical nasal correction forms an important adjunct to the primary nasal repair at the time of primary lip repair. However, acceptance of nasoalveolar molding in Indian set-up has not been wide spread due to various reasons such as lack of the resources and inability of the parents to comply with the frequent adjustment schedule. At the Nitte Meenakshi Institute of Craniofacial surgery at the Nitte University, Mangalore, authors have developed a modification of the PNAM appliance previously described in the literature. The key modification is done at the time of fabrication of the occlusal prosthesis. This modification has made the overall procedure simpler and at the same time helped to reduce the recall visits by half of the originally required. This article describes the fabrication procedure of the modified nasal alveolar molding appliance and the modified treatment protocol in a stepwise manner.     

Improving postoperative pain management in subpectoral tissue expander implant reconstruction of the breast using an elastomeric pump

IntroductionPostoperative pain after breast surgery is one of the major factors contributing to delay in mobilisation and prolonged hospital stay. A retrospective analysis was performed of patients undergoing skin sparing mastectomy and insertion of a subpectoral implant. The aim was to determine whether the use of an elastomeric local anaesthetic pump improved pain control and length of stay.MethodsTwenty-five consecutive patients undergoing the above procedure were sited with an elastomeric local anaesthetic infusion pump intraoperatively, in addition to standard regular and pro re nata analgesia. The control group comprised 25 patients undergoing the same procedure in the same year who received standard analgesia alone. Visual analogue scale scores were recorded for the duration of inpatient stay, as was any further analgesic requirement.ResultsThe median age was 51 years (range: 26–75 years) in the intervention group and 50 years (range: 28–70 years) in the control group. The mean visual analogue scale score was 0.28 (standard deviation [SD]: 0.61) at 24 hours for the intervention group and 1.84 (SD: 0.37) for the control group (p<0.0001). The mean length of stay was 1.8 days (SD: 0.71 days) for the intervention group and 2.28 days (SD: 0.94 days) for the control group (p=0.15). There were no complications involving catheter placement, leakage or toxicity relating to use of the local anaesthetic.ConclusionsThere was significantly reduced pain with the use of the local anaesthetic infusion pump. The elastomeric pump is a step towards enhanced patient recovery after breast surgery in the case of skin sparing mastectomy and subpectoral tissue expander reconstruction.     

Stimulus level effects on speech-evoked obligatory cortical auditory evoked potentials in infants with normal hearing

ObjectiveTo determine stimulus level effects on speech-evoked cortical auditory evoked potentials (CAEPs) in infants for a low (/m/) and high (/t/) frequency speech sound.MethodsCAEPs were recorded for two natural speech tokens, /m/ and /t/. Participants were 16 infants aged 3–8 months with no risk factors for hearing impairment, no parental concern regarding hearing or development, and normal tympanograms and otoacoustic emissions. Infants were either tested at levels of 30, 50, and 70 dB SPL or at 40, 60, and 80 dB SPL, in counterbalanced order.ResultsInput–output functions show different effects of increasing sound level between stimuli. There were minimal changes in latency with increase in level for /t/. For /m/, there were approximately 50–60 ms latency increases at soft compared to loud levels. Amplitudes saturated at moderate–high levels (60–80 dB SPL) for both stimuli.ConclusionsInfants’ CAEP input–output functions differ for /t/ versus /m/ and differ from those previously reported for adults for other stimuli. Effects of stimulus and level on CAEPs should be considered when using CAEPs for hearing aid or cochlear implant evaluation in infants.SignificanceSpeech-evoked CAEPs provide an objective measure of central auditory processing. Possible differences in CAEP growth between infants and adults suggest developmental effects on intensity coding by the auditory cortex.