Primary neurolymphomatosis (NL) is a rare condition that refers to lymphomas primarily presenting... more Primary neurolymphomatosis (NL) is a rare condition that refers to lymphomas primarily presenting in cranial or peripheral nerves. Similar to primary central nervous system lymphoma (PCNSL), almost all cases of neurolymphomatosis are histologically classified as high-grade diffuse B cell lymphoma. Primary involvement of cranial nerves is extremely rare and manifests with signs and symptoms of mass effect. We present the case of a 67year-old right-handed male who presented to hospital with progressive horizontal diplopia and left facial numbness in the V1 and V2 distributions. The patient subsequently developed ataxia, dizziness, and nausea. An open biopsy was performed which confirmed the diagnosis of diffuse B cell lymphoma. The patient experienced rapid clinical improvement after the administration of chemotherapy. A comprehensive search of literature using the MEDLINE and EMBASE database yielded 9 previous cases of primary neurolymphomatosis in the cranial nerves and these are reviewed here. However, to date, this is the first reported case involving the trigeminal nerve in the cavernous sinus while concurrently causing mass effect on the lower cranial nerves.
Poster: "ECR 2016 / B-0173 / Diagnostic reference levels for emergency head CT in paediatric... more Poster: "ECR 2016 / B-0173 / Diagnostic reference levels for emergency head CT in paediatric patients" by: "Z. Vawda, W. Groenewald, J. M. Akudugu, R. D. PITCHER; Cape Town/ZA"
Purpose To assess the effect of upright, seated, and supine postures on lumbar muscle morphometry... more Purpose To assess the effect of upright, seated, and supine postures on lumbar muscle morphometry at multiple spinal levels and for multiple muscles. Methods Six asymptomatic volunteers were imaged (0.5 T upright open MRI) in 7 postures (standing, standing holding 8 kg, standing 45° flexion, seated 45° flexion, seated upright, seated 45° extension, and supine), with scans at L3/L4, L4/L5, and L5/S1. Muscle cross-sectional area (CSA) and muscle position with respect to the vertebral body centroid (radius and angle) were measured for the multifidus/erector spinae combined and psoas major muscles. Results Posture significantly affected the multifidus/erector spinae CSA with decreasing CSA from straight postures (standing and supine) to seated and flexed postures (up to 19%). Psoas major CSA significantly varied with vertebral level with opposite trends due to posture at L3/L4 (increasing CSA, up to 36%) and L5/S1 (decreasing CSA, up to 40%) with sitting/ flexion. For both muscle groups, radius and angle followed similar trends with decreasing radius (up to 5%) and increasing angle (up to 12%) with seated/flexed postures. CSA and lumbar lordosis had some correlation (multifidus/erector spinae L4/L5 and L5/S1, r = 0.37-0.45; PS L3/L4 left, r = − 0.51). There was generally good repeatability (average ICC(3, 1): posture = 0.81, intra = 0.89, inter = 0.82). Conclusion Changes in multifidus/erector spinae muscle CSA likely represent muscles stretching between upright and seated/flexed postures. For the psoas major, the differential level effect suggests that changing three-dimensional muscle morphometry with flexion is not uniform along the muscle length. The muscle and spinal level-dependent effects of posture and spinal curvature correlation, including muscle CSA and position, highlight considering measured muscle morphometry from different postures in spine models.
29th Annual Meeting North American Skull Base Society, 2019
Primary neurolymphomatosis (NL) is a rare condition that refers to lymphomas primarily presenting... more Primary neurolymphomatosis (NL) is a rare condition that refers to lymphomas primarily presenting in cranial or peripheral nerves. Similar to primary central nervous system lymphoma (PCNSL), almost all cases of neurolymphomatosis are histologically classified as high-grade diffuse B cell lymphoma. Primary involvement of cranial nerves is extremely rare and manifests with signs and symptoms of mass effect. We present the case of a 67year-old right-handed male who presented to hospital with progressive horizontal diplopia and left facial numbness in the V1 and V2 distributions. The patient subsequently developed ataxia, dizziness, and nausea. An open biopsy was performed which confirmed the diagnosis of diffuse B cell lymphoma. The patient experienced rapid clinical improvement after the administration of chemotherapy. A comprehensive search of literature using the MEDLINE and EMBASE database yielded 9 previous cases of primary neurolymphomatosis in the cranial nerves and these are reviewed here. However, to date, this is the first reported case involving the trigeminal nerve in the cavernous sinus while concurrently causing mass effect on the lower cranial nerves.
Objectives: To establish local diagnostic reference levels (LDRLs) for emergency paediatric head ... more Objectives: To establish local diagnostic reference levels (LDRLs) for emergency paediatric head computed tomography (CT) scans performed at a South African (SA) tertiary-level hospital and to compare these with published data.Materials and methods: A retrospective analysis was conducted of volume-based CT dose index (CTDIvol) and dose length product (DLP) data from uncontrasted paediatric head CT scans performed in the Trauma and Emergency Unit of a tertiary-level SA hospital from January to June 2013. A random sample of 30 patients in each of 3 age groups (0–2, >2–5 and >5–10 years) was used. LDRL values were compared with several national DRLs from Europe and Australia. Results: Mean CTDIvol and DLP values were: 30 mGy and 488 mGy.cm for the 0–2 years age group; 31 mGy and 508 mGy.cm for the >2–5 years group, and 32 mGy and 563 mGy.cm for the >5–10 years group, respectively. The mean DLP for 0–2 year-olds was the only parameter outside the range of corresponding publi...
Nephrogenic systemic fibrosis (NSF), unknown before March 1997 and first described in 2000, is a ... more Nephrogenic systemic fibrosis (NSF), unknown before March 1997 and first described in 2000, is a systemic disorder characterised by widespread tissue fibrosis. The first known case occurred in 1997, after the use of gadolinium-based contrast agents (GBCAs) at high doses in patients with renal failure had become routine. An overwhelming majority occurred within weeks to months after injection of a GBCA. This note comprises guidelines on the prevention of NSF.
Primary neurolymphomatosis (NL) is a rare condition that refers to lymphomas primarily presenting... more Primary neurolymphomatosis (NL) is a rare condition that refers to lymphomas primarily presenting in cranial or peripheral nerves. Similar to primary central nervous system lymphoma (PCNSL), almost all cases of neurolymphomatosis are histologically classified as high-grade diffuse B cell lymphoma. Primary involvement of cranial nerves is extremely rare and manifests with signs and symptoms of mass effect. We present the case of a 67year-old right-handed male who presented to hospital with progressive horizontal diplopia and left facial numbness in the V1 and V2 distributions. The patient subsequently developed ataxia, dizziness, and nausea. An open biopsy was performed which confirmed the diagnosis of diffuse B cell lymphoma. The patient experienced rapid clinical improvement after the administration of chemotherapy. A comprehensive search of literature using the MEDLINE and EMBASE database yielded 9 previous cases of primary neurolymphomatosis in the cranial nerves and these are reviewed here. However, to date, this is the first reported case involving the trigeminal nerve in the cavernous sinus while concurrently causing mass effect on the lower cranial nerves.
Poster: "ECR 2016 / B-0173 / Diagnostic reference levels for emergency head CT in paediatric... more Poster: "ECR 2016 / B-0173 / Diagnostic reference levels for emergency head CT in paediatric patients" by: "Z. Vawda, W. Groenewald, J. M. Akudugu, R. D. PITCHER; Cape Town/ZA"
Purpose To assess the effect of upright, seated, and supine postures on lumbar muscle morphometry... more Purpose To assess the effect of upright, seated, and supine postures on lumbar muscle morphometry at multiple spinal levels and for multiple muscles. Methods Six asymptomatic volunteers were imaged (0.5 T upright open MRI) in 7 postures (standing, standing holding 8 kg, standing 45° flexion, seated 45° flexion, seated upright, seated 45° extension, and supine), with scans at L3/L4, L4/L5, and L5/S1. Muscle cross-sectional area (CSA) and muscle position with respect to the vertebral body centroid (radius and angle) were measured for the multifidus/erector spinae combined and psoas major muscles. Results Posture significantly affected the multifidus/erector spinae CSA with decreasing CSA from straight postures (standing and supine) to seated and flexed postures (up to 19%). Psoas major CSA significantly varied with vertebral level with opposite trends due to posture at L3/L4 (increasing CSA, up to 36%) and L5/S1 (decreasing CSA, up to 40%) with sitting/ flexion. For both muscle groups, radius and angle followed similar trends with decreasing radius (up to 5%) and increasing angle (up to 12%) with seated/flexed postures. CSA and lumbar lordosis had some correlation (multifidus/erector spinae L4/L5 and L5/S1, r = 0.37-0.45; PS L3/L4 left, r = − 0.51). There was generally good repeatability (average ICC(3, 1): posture = 0.81, intra = 0.89, inter = 0.82). Conclusion Changes in multifidus/erector spinae muscle CSA likely represent muscles stretching between upright and seated/flexed postures. For the psoas major, the differential level effect suggests that changing three-dimensional muscle morphometry with flexion is not uniform along the muscle length. The muscle and spinal level-dependent effects of posture and spinal curvature correlation, including muscle CSA and position, highlight considering measured muscle morphometry from different postures in spine models.
29th Annual Meeting North American Skull Base Society, 2019
Primary neurolymphomatosis (NL) is a rare condition that refers to lymphomas primarily presenting... more Primary neurolymphomatosis (NL) is a rare condition that refers to lymphomas primarily presenting in cranial or peripheral nerves. Similar to primary central nervous system lymphoma (PCNSL), almost all cases of neurolymphomatosis are histologically classified as high-grade diffuse B cell lymphoma. Primary involvement of cranial nerves is extremely rare and manifests with signs and symptoms of mass effect. We present the case of a 67year-old right-handed male who presented to hospital with progressive horizontal diplopia and left facial numbness in the V1 and V2 distributions. The patient subsequently developed ataxia, dizziness, and nausea. An open biopsy was performed which confirmed the diagnosis of diffuse B cell lymphoma. The patient experienced rapid clinical improvement after the administration of chemotherapy. A comprehensive search of literature using the MEDLINE and EMBASE database yielded 9 previous cases of primary neurolymphomatosis in the cranial nerves and these are reviewed here. However, to date, this is the first reported case involving the trigeminal nerve in the cavernous sinus while concurrently causing mass effect on the lower cranial nerves.
Objectives: To establish local diagnostic reference levels (LDRLs) for emergency paediatric head ... more Objectives: To establish local diagnostic reference levels (LDRLs) for emergency paediatric head computed tomography (CT) scans performed at a South African (SA) tertiary-level hospital and to compare these with published data.Materials and methods: A retrospective analysis was conducted of volume-based CT dose index (CTDIvol) and dose length product (DLP) data from uncontrasted paediatric head CT scans performed in the Trauma and Emergency Unit of a tertiary-level SA hospital from January to June 2013. A random sample of 30 patients in each of 3 age groups (0–2, >2–5 and >5–10 years) was used. LDRL values were compared with several national DRLs from Europe and Australia. Results: Mean CTDIvol and DLP values were: 30 mGy and 488 mGy.cm for the 0–2 years age group; 31 mGy and 508 mGy.cm for the >2–5 years group, and 32 mGy and 563 mGy.cm for the >5–10 years group, respectively. The mean DLP for 0–2 year-olds was the only parameter outside the range of corresponding publi...
Nephrogenic systemic fibrosis (NSF), unknown before March 1997 and first described in 2000, is a ... more Nephrogenic systemic fibrosis (NSF), unknown before March 1997 and first described in 2000, is a systemic disorder characterised by widespread tissue fibrosis. The first known case occurred in 1997, after the use of gadolinium-based contrast agents (GBCAs) at high doses in patients with renal failure had become routine. An overwhelming majority occurred within weeks to months after injection of a GBCA. This note comprises guidelines on the prevention of NSF.
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