Evaluation of Renal Artery Variations in Horseshoe Kidneys with Computed Tomography.

OBJECTIVE: Horseshoe kidney is the most common renal fusion anomaly, accounting for 90%. The study aims to explore the variations in the renal arteries of individuals with horseshoe kidney anomalies and contribute to the classification in the literature. MATERIALS AND METHODS: Computed tomography images of 145 individuals who had intravenous contrast-enhanced abdominal computed tomography for any reason and had horseshoe kidney anomalies were analyzed retrospectively, and the presence, origin, and number of accessory renal arteries were evaluated. Then, classification was performed according to the origin of the accessory arteries. RESULTS: In 145 individuals, 44 different combinations of the accessory artery according to the origin and number were obtained. Most common accessory artery combination was type 2a (M1). According to our classification, 13.1% of the patients were type 1, 57.2% were type 2, 17.2% were type 3, 10.3% were type 4, and 1.4% were type 5. CONCLUSION: The classifications of arterial variations in horseshoe kidney anomalies did not match each other in previous studies and did not comprise all patients because they were conducted with a small number of cases. A more comprehensive new classification was created in our study according to accessory artery origins with the help of previous studies.

Evaluation of Arachnoid Granulations in Cranial Dural Sinuses with Contrast-Enhanced 3-Dimensional T1-Weighted Magnetic Resonance Imaging.

OBJECTIVE: Several studies in the literature have used contrast-enhanced magnetic resonance imaging to investigate arachnoid granulations protruding into the cranial dural sinuses. The current study aimed to investigate the protrusion of arachnoid granulations into the superior sagittal sinus, transverse sinus, straight sinus, and confluence of sinuses and determine the frequency of brain herniation into giant arachnoid granulations using contrast-enhanced 3-dimensional T1-weighted magnetic resonance imaging. MATERIALS AND METHODS: Images of 550 patients with intra-sinus arachnoid granulations who underwent contrast-enhanced 3-dimensional T1-weighted thin-slice magnetic resonance imaging were retrospectively re-evaluated. Only 300 patients with at least 1 intra-sinus arachnoid granulation were included in the study. The protrusion of arachnoid granulations into superior sagittal sinus, transverse sinus, straight sinus, and confluence of sinuses was investigated. In addition, large arachnoid granulations and brain herniations into arachnoid granulations were also noted. RESULTS: A total of 889 focal filling defects of arachnoid granulations, at least 1 in the dural sinus, were detected. Of the filling defects of arachnoid granulations, 183 were in the right transverse sinus, 222 in the left transverse sinus, 265 in superior sagittal sinus, 185 in straight sinus, and 34 in confluence of sinuses. Brain herniation into arachnoid granulations was detected in 8 (2.7%) of the patients included in the study. All the filling defects detected in the dural sinuses on post-contrast 3-dimensional T1-weighted images were isointense with cerebrospinal fluid and had round, oval, or lobulated contours. A positive weak correla- tion was found between patient age and the size and number of arachnoid granulations (r = 0.181, P < .01 and r=0.207, P < .001, respectively). It was observed that the size and number of arachnoid granulations increased as the age of the patients increased. CONCLUSIONS: The distribution, shape, number, and size of intra-sinus arachnoid granulations can vary considerably. Brain herniation into arachnoid granulation can also be seen. Three-dimensional cranial magnetic resonance imaging sequences can be safely used in the evaluation of arachnoid granulations.

Can the sigmoid notch sign be used on cranial computed tomography to differentiate between thrombosis and hypoplasia of the cerebral transverse venous sinus?

OBJECT: In patients with headache, the distinction between transverse sinus (TS) atresia/hypoplasia and TS thrombosis in cranial magnetic resonance venography (MRV) may be misleading. In this study, we aimed to distinguish TS thrombosis from atretic or severely hypoplastic TS, with the help of cranial computed tomography (CT). METHOD: Non-contrast cranial CT scans of 51 patients with no or severely thin signal on MRV were analyzed retrospectively using the bone window. Absence or asymmetry of the sigmoid notches on the CT predicted atretic or severe hypoplastic TS, and symmetry predicted thrombotic TS. Afterwards, it was investigated whether the patient's other imaging findings and confirmed diagnoses matched with the predictions. FINDINGS: Of the 51 patients included in the study, 15 were diagnosed with TS thrombosis, and 36 were diagnosed with atretic/hypoplastic TS. All 36 of the congenital atresia/hypoplasia diagnoses were correctly predicted. Thrombosis was predicted correctly in 14 of 15 patients with TS thrombosis. In cranial CT, the symmetry or asymmetry of the sigmoid notch sign was examined, and it was found that the evaluation predicted with 93.3% sensitivity (95% confidence interval (CI): 68.05-99.83) and 100% specificity (95% CI: 90.26-100.00) the distinction between TS thrombosis and atretic/hypoplastic sinus. CONCLUSION: Symmetry or asymmetry of the sigmoid notch on CT is a reliable method that can be used to differentiate congenital atresia/hypoplasia from the TS thrombosis in patients with very thin or absent TS signal on the cranial MRV.

The utility of quantitative MRI parameters in discriminating progressive supranuclear palsy from Parkinson's disease.

OBJECTIVE: We sought to re-evaluate the utility of all the quantitative neuroimaging parameters attributed to progressive supranuclear palsy (PSP) in discrimination between PSP and Parkinson' s disease (PD) subjects in our cohort. We aimed to propose some practical clinical remarks in this field. METHODS: In our retrospective study, 19 patients with 'probable' PSP and 37 patients with PD were enrolled. The radiological measurements of PSP, described in the previous reports, have been calculated in all subjects. The comparisons between the groups were performed and the measures regarding the accuracy of these parameters in the differentiation of PSP from PD subjects were analyzed. RESULTS: We found that the values of magnetic resonance parkinsonism index-2 (MRPI-2), pontine-to-midbrain area (P/M) ratio, P/M 2 ratio, and 3rdV/bifrontal width ratio had high AUC values and very good discriminative powers. The analyses revealed that; for the discrimination of PSP from PD subjects, a 3rdvent/bifrontal width cut-off value of 0.30 had 42.1 % sensitivity and 97.3 % specificity; a P/M cut-off value of 6.03 had a 52.6 % sensitivity and 97.3 % specificity; and an MRPI-2 cut-off value of 7.43 had 57.9 % sensitivity and 97.3 % specificity. Remarkably, we also found that the presence of high values for both P/M and 3rdV/bifrontal ventricle rate had a positive predictive value of 100% for the diagnosis of PSP. CONCLUSION: Our study results support the utility of previously defined neuroimaging parameters in distinguishing PSP and PD subjects. Besides, combined use of a high P/M ratio and 3rdV/bifrontal width may be practical and present strictly high evidence for the diagnosis of PSP.

Evaluation of the frequency of tentorial hypoplasia and accompanying gyral herniation using MRI.

Purpose The cerebellar tentorium, the second-largest dural reflection in the brain, separates supratentorial and infratentorial structures. This study aimed to determine the frequency of tentorial hypoplasia (TH) and gyral herniation and their relationship with clinical findings. Methods The standard brain MRIs were examined retrospectively. The presence of TH and laterality were investigated. If hypoplasia was accompanied by a gyrus extending inferior to the line where the tentorium should be located, this was recorded as tentorial hypoplasia-herniated gyrus (TH-HG), while the cases with hypoplasia alone were noted as isolated TH. It was also determined which gyrus or gyri were herniated. The clinical findings of the patients were obtained, and the correlation between HG was explored. Results Standard brain MRIs of the 2051 patients were evaluated. Two hundred ten patients were excluded from the study due to different intracranial disorders, and 1841 patients, 739 (40.1%) males, and 1102 (59.9%) females, were included. Isolated TH or TH-HG was present in 56 patients, resulting in a prevalence of 3.04%. Of the patients with TH or TH-HG, 15 were men, and 41 were women. TH and TH-HG were significantly more common in women (p=0.038). TH-HG was unilateral in 22 (39.2%) patients and bilateral in 21 (37.5%). Left TH was found in 11 (19.6%) patients, left TH-HG in 29 (51.7%), right TH in eight (14.2%), and left TH-HG in 35 (62.5%). Conclusion Hypoplasia of the tentorium is a rare and unknown anomaly that can be easily diagnosed using MRI, and different gyral herniations may accompany TH.

Frequency of Hypoplasia of the Vertebral Body at L5, and Its Relationship with Degeneration in Patients with Low Back Pain.

AIM: To explain the association between vertebral body hypoplasia and degenerative changes in the discovertebral complex and facet joints, and to assess the incidence of hypoplasia of the vertebral body at the L5 level. MATERIAL AND METHODS: A retrospective analysis was made of 3,100 patients aged 20?50 years who underwent lumbar MRI with a complaint of back pain, of which 55 were identified with vertebral body hypoplasia. Intervertebral disc degeneration was evaluated in the study using the Pfirrmann and Modified Pfirrmann classification systems, while degenerative changes in the vertebrae endplate were assessed using the Modic classification system. Osteoarthritis of the facet joint was graded at the L4-5 level, and spondylolysis and spondylolisthesis rates were compared between the control group and the hypoplasic group. RESULTS: The incidence of hypoplasia of the vertebral body at the L5 level was found to be 1.8% in the population with back pain in the 20?50-year age group. In the hypoplasia group, disc degeneration was detected at a higher rate than in the control group (p < 0.001). The distribution of Modic signal changes in the superior and inferior endplates of the vertebrae differed significantly between the hypoplasia and control groups (p < 0.001).The rate of spondylolysis was 7.7% in the control group and 65.5% in the hypoplasia group (p < 0.001), and spondylolisthesis was significantly more common in the hypoplasia group (18.4%, p < 0.001). In addition, facet joint degeneration was identified more frequently in the hypoplasia group. Degenerative findings were detected in 74.5% of the right posterior intervertebral joints, and in 70.9% of the left posterior intervertebral joints in the hypoplasia group. CONCLUSION: Vertebral body hypoplasia is a predisposing factor for disc degeneration, facet osteoarthritis and degeneration in the vertebral endplates, and has also been associated with spondylolysis and spondylolisthesis.

de Quervain's Tenosynovitis and Radial Styloid Osseous Changes.

Objectives: This study aimed to determine the radial styloid osseous changes observed on posteroanterior wrist radiographs of patients with de Quervain's tenosynovitis who required surgery or conservative treatment. Materials and Methods: The surgically treated group included 24 patients with de Quervain's tenosynovitis. The conservative treatment group and the healthy control group each comprised 24 age- and sex-matched subjects. We evaluated the presence of bone apposition, periosteal reaction, sclerosis, osteopenia, erosion, and contour bulge in the epiphyseal remnant at the radial styloid. The incidences of abnormal radiographic findings were compared between these three groups. The correlation of radial styloid bony changes with the duration of symptoms was also analyzed. Results: No significant differences were found between the three groups in terms of periosteal reaction, erosion, and contour bulge at the epiphysial remnant. Significant differences were found between the three groups in the incidence of bone apposition, sclerosis, and osteopenia (p < 0.001). Bone apposition incidence in the surgically and conservatively treated groups was significantly higher than that in the control group (p < 0.001). Sclerosis and osteopenia significantly differed between the surgically and conservatively treated groups (p < 0.001, p = 0.002, respectively). No significant association was observed between the duration of symptoms and the radial styloid osseous changes (p > 0.05). Conclusion: We found a variable incidence of abnormal radiographic findings on the radial styloid in patients with de Quervain's tenosynovitis and asymptomatic individuals. The presence of sclerosis and osteopenia may be potential risk factors for patients who do not respond to conservative treatment and need surgical intervention.

Normative Measurements and Apparent Diffusion Coefficient Values of Parotid Lymph Nodes on Magnetic Resonance Imaging.

OBJECTIVE: To determine the morphological features and apparent diffusion coefficient (ADC) values of normal intraparotid lymph nodes (IPLNs) obtained from the MRI examination. STUDY DESIGN: Cross-sectional descriptive study. PLACE AND DURATION OF STUDY: Health Sciences University, Diskapi Yildirim Beyazit Training and Research Hospital, Department of Radiology, Ankara, Turkey, from January 2018 to December 2021. METHODOLOGY: The study included 232 patients who underwent neck MRI examination. The long axis diameter (LAD) was measured as the largest diameter of the IPLN, and the short axis diameter (SAD) was measured perpendicular to the LAD. ADC measurements were undertaken by placing the largest region of interest suitable for the size of the IPLNs. RESULTS: A total of 394 lymph nodes were evaluated. The median LAD and SAD of the lymph nodes were 5.50 (2.50) mm and 3.50 (2.00) mm, respectively. The LAD was 9 mm or lower in 95.7% of the lymph nodes; the SAD was 6 mm or lower in 94.7%. The ADC map was evaluated in 275 IPLNs, with the median ADC value being calculated as 0.77(0.18)x10-3 mm2/s. The ADC value was 1.05x10-3 mm2/s or lower in 96.3% of the lymph nodes. CONCLUSION: A SAD of 6 mm; and a LAD of 9 mm could be used as normalcy criteria in IPLNs. Normal IPLNs may have an ADC of 1.05x10-3 mm2/s or lower. Considering that benign IPLNs may have low ADC values, those can prevent false-positive results in terms of malignancy. KEY WORDS: Parotid glands, Lymph nodes, Magnetic resonance imaging, Apparent diffusion coefficient.

Frequency of Ipsilateral Axillary Lymphadenopathy After the Inactivated COVID-19 Vaccine.

OBJECTIVE: During COVID-19 vaccine development studies, vaccines' efficacy and safety profiles should be carefully investigated. Only a few studies have shown that the COVID-19 vaccine can cause axillary lymphadenopathy on the injection arm. This study aimed to investigate the incidence of axillary lymphadenopathy and imaging findings using B-mode and Doppler ultrasonography (US) examinations in volunteers who had recently been vaccinated against COVID-19. METHODS: The ipsilateral and contralateral axillae of 101 volunteers who received the COVID-19 vaccine were evaluated using B-mode and Doppler US examinations. The volunteers were asked when and to which arm the vaccine had been applied, and the type and dose of the vaccine were recorded. It was also questioned whether the individual experienced any side effects after vaccination, such as pain, tenderness, fever, and redness at the injection site. In addition, the demographic data of the participants, such as age and gender, were recorded. RESULTS: The B-mode US examinations revealed that the long- and short-axis diameters, size, cortical thickness, and asymmetric cortical thickening of the left axillary lymph nodes were significantly higher compared to the right side in individuals having received the CoronaVac vaccine (p<0.05). When the individuals were evaluated separately according to gender, the frequency of cortical thickness and asymmetric cortical thickening in the left axillary lymph nodes was higher than on the right side in both males and females (p=0.011). CONCLUSION: It should be kept in mind that ipsilateral reactive lymphadenopathy may develop after the COVID-19 vaccine. This knowledge can prevent unnecessary axillary lymph node biopsies.

An extrahepatic hydatid cyst with the fat-fluid level.

A hydatic cyst is a zoonosis caused by the larva of a tapeworm Echinococcus granulosus. The liver is the most commonly affected organ. Soft tissue localization has been reported in 2.3% of cases. Herein, we present a patient with a fat-containing hydatid cyst located in the left thigh. There are only a few reports in the literature on the presence of the fat-fluid level within a hydatid cyst. Previous studies have suggested that fat-containing hydatid cysts occur due to their cysto-biliary communication in the liver. In our case, we describe a fat-containing hydatid cyst in the extrahepatic location and discuss the pathophysiologic mechanism of fat inside it.

The Overlap in Neuroimaging Findings Between Idiopathic Normal Pressure Hydrocephalus and Progressive Supranuclear Palsy.

Background: The neuroimaging findings of brain stem atrophy resembling progressive supranuclear palsy (PSP) radiology are common in idiopathic normal pressure hydrocephalus (iNPH) subjects. Besides, recent studies report the existence of iNPH-like MRI findings in PSP subjects. We aimed to comparatively investigate the neuroimaging indices of iNPH and PSP in our patient groups in a detailed methodology. Methods: Ultimately, 19 probable PSP patients and 18 patients with a definite diagnosis of iNPH were enrolled. The subjects were recruited retrospectively from those who had been admitted between 2017 and 2021 to the Movement Disorders Polyclinic and the Neurosurgery Clinic of the Diskapi Yildirim Beyazit Training and Education Hospital. MRI-based DESH score, Evans index, and the callosal angle (CA) have been calculated in all the individuals. Besides, quantitative MRI parameters of PSP were evaluated in every subject. Statistical analyses were performed using IBM SPSS Statistics 26. Results: The comparative analyses regarding the radiological parameters of PSP did not reveal any difference between patient groups. On the other hand, the comparisons of the neuroimaging parameters of iNPH, yielded differences in the CA, CA score, and the total DESH score. However, the ROC curve analyses did not reveal a discriminative power at a value of "very good" or "excellent" in any of the indices. Conclusions: We found that the neuroimaging features of iNPH and PSP highly overlapped between these patient groups. These results may provide indirect evidence regarding the coexistence of PSP and iNPH pathophysiology that has been deliberated in several recent reports.

Absence of CSF flow within the cerebral aqueduct in spontaneous intracranial hypotension: a report of two cases.

Spontaneous intracranial hypotension (SIH) is a potentially debilitating condition resulting from a low cerebrospinal fluid (CSF) volume secondary to spinal CSF leakage. Characteristic clinical and radiological imaging findings are helpful in diagnosis. Herein, we present and discuss the magnetic resonance imaging (MRI) and CSF flow study of two patients with SIH and no CSF flow within the cerebral aqueduct, which is extremely rare in the literature.

Role of magnetic resonance spectroscopy in differential diagnosis of solitary pulmonary lesions.

PURPOSE: The aim of our study was to evaluate the availability of magnetic resonance spectroscopy (MRS) for the differentiation of benign or malignant pulmonary nodules and masses. METHODS: A total of 59 patients (45 male, 14 female) with pulmonary nodules and masses were included in this prospective study. MRS was applied to the pulmonary lesions of the patients and choline levels were determined. Afterwards CT-guided percutaneous needle biopsy was performed. According to the biopsy results, pulmonary lesions were benign in 25 patients and malignant in 34 patients. RESULTS: Choline levels were significantly higher in malignant lesions compared with benign lesions (p < 0.001). When the other conditions were kept constant, the probability of malignancy significantly increased by 17.38-fold (95% CI, 3.78-79.93) in those with choline levels >1.65 µmol/g compared to those with choline levels ≤1.65 µmol/g (p < 0.001). CONCLUSION: MRS is a noninvasive method that can be used in the differential diagnosis of pulmonary nodules and masses.

Advanced Magnetic Resonance Imaging Findings of Multinodular and Vacuolating Neuronal Tumor.

AIM: To present the magnetic resonance imaging (MRI) findings of a multinodular and vacuolating neuronal tumor (MVNT). MATERIAL AND METHODS: The authors identified four patients with MVNT in the hospital between January 2015 and October 2019. Both the clinical and radiological data of the patients were collected for analysis. RESULTS: Three patients complained of non-specific headaches. One patient had vertigo and imbalance. MRI sequences, including spectroscopy, perfusion, and DWI sequences, were retrospectively evaluated. The lesions were located in the subcortical and periventricular white matter of the parietal and temporal lobes, showed confluency, and comprised nodular pattern. The lesions appeared isointense to the cerebral cortex on T1 weighted imaging and hyperintense on T2 weighted and FLAIR sequences. None of the lesions showed diffusion restriction or contrast enhancement. Three of the lesions demonstrated a slight increase in choline peak and a slight decrease in N-acetyl aspartate peak. One lesion showed a noticeable increase in the Cho peak and a decrease in the NAA peak. CONCLUSION: Radiological features of MVNT are specific. Recognizing the MRI findings would help avoid unnecessary interventions in these patients, who are usually asymptomatic.

Neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios as inflammation markers in patients with papilledema due to idiopathic intracranial hypertension.

Purpose: The aim of this study was to investigate the role of inflammation in the pathogenesis of idiopathic intracranial hypertension (IIH) using the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) as inflammation markers. Methods: The files of 33 IIH patients and 33 controls were screened for this retrospective study. For each patient, the NLR and PLR values were calculated using a single fasting blood sample. For both eyes, papilledema (PE) grades, best-corrected visual acuity (BCVA), retinal nerve fiber layer thickness (RNFLT), and ganglion cell layer thickness (GCLT) measurements were recorded along with the demographic data, including body mass index (BMI), and complete neurological and ophthalmological findings. Comparisons between the two groups and between the IIH patients with and without PE were made. The associations of NLR and PLR with all other parameters were analyzed independently from age, gender, and BMI. Results: NLR and PLR were higher in patients with IIH than controls (P < 0.05). They were also higher in patients with PE (P < 0.05) in the IIH group. NLR and PLR were found to be associated with BCVA (P < 0.001 and P = 0.023, respectively), global RNFLT (P = 0.004 and 0.012, respectively), RNFLT of the temporal quadrant (P < 0.001 and P = 0.042, respectively) and PE grade (P < 0.001 and P = 0.035, respectively). Conclusion: The NLR and PLR values and their associations with BCVA, RNFLT, and PE support the hypothesis that inflammation is a very important component of the pathogenesis of IIH.

Fetal posterior cerebral artery duplication, true fetal posterior cerebral artery variation and trifurcation anterior cerebral artery association.

We would like to present a case with fetal posterior cerebral artery duplication and anterior cerebral artery trifurcation, which we detected using magnetic resonance angiography. We believe this is the first case defined in the literature. Embryological explanation of posterior cerebral artery variations is discussed in light of the literature.

Spontaneous regression of extruded lumbar disc herniation: Correlation with clinical outcome.

OBJECTIVE: To evaluate the natural history of lumbar extruded disc with conservative treatment on MRI and to assess relation between the radiologic changes and clinical outcome. METHODS: This prospective observational study was conducted at University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital between May 2015-June 2018. It included consecutive patients who were diagnosed as having lumbar symptomatic extruded disc as shown in MRI. After an average period of 17.0±7.2 months, repeat MRI was taken in 40 patients who received only conservative care during follow-up. Changes in the volume of herniated disc was measured. The patients were assigned into 3 groups as follow: (1) non-regression, (2) partial-regression, and (3) complete resolution. Numeric Rating Scale (NRS) pain score, the Oswestry Low Back Pain Disability Index (ODI) and muscle weakness were evaluated. RESULTS: Based on disc volume of the T2-weighted MR images; four patients (10%) did not show any regression, six patients (15%) had a partial regression, and 30 patients (75%) had a complete resolution. Patients with complete resolution showed a significant improvement in the NRS pain score and the ODI score (p<0,001) over time. In patients with partial regression, only the ODI score improved significantly (p=0,043). Non-regression group did not show any improvement in any clinical outcome measure (p>0,05). Changes in the NRS scores over time were significantly higher in complete resolution group compared to non-regression group (p=0.016). CONCLUSION: The majority of the patients with extruded lumbar disc herniation might have reduction in size of herniated disc in the long run along with improvement in symptoms and function with conservative care.

Correlation Between Medial Meniscal Extrusion Determined by Dynamic Ultrasound and Magnetic Resonance Imaging Findings of Medial-Type Knee Osteoarthritis in Patients With Knee Pain.

OBJECTIVES: The aim of our study was to investigate the relationship between medial meniscal extrusion (MME) determined by dynamic ultrasound (US) and magnetic resonance imaging findings of medial-type knee osteoarthritis (OA). METHODS: Single knees of 102 patients with knee pain were assessed by radiography, dynamic US, and magnetic resonance imaging. All knee radiographs were interpreted and grouped according to the Kellgren-Lawrence (KL) scale. Medial meniscal extrusion in non-weight-bearing and weight-bearing positions and the difference of these values (ΔMME) were measured by dynamic US. The medial tibiofemoral compartments of all knees were evaluated and grouped according to the Whole-Organ Magnetic Resonance Imaging Score (WORMS). Mean values of non-weight-bearing MME, weight-bearing MME, and ΔMME ± standard deviations for groups formed according to the KL scale and WORMS system were compared. RESULTS: We demonstrated that different from non-weight-bearing MME, weight-bearing MME was significantly correlated with not only high grades but also lower grades of cartilage damage and subchondral bone marrow lesions in medial-type knee OA. Although the difference in non-weight-bearing MME between cartilage status groups 1 and 2 was not significant (P = .071), there were significant differences in of weight-bearing MME between groups 1 and 2, between groups 2 and 3, and between groups 3 and group 4 (P = .003, .002, and .032, respectively). CONCLUSIONS: We found statistically significant associations between MME values and the severity of the OA findings according to both the KL scale and WORMS system. We offer dynamic US as an initial tool for the diagnosis and a screening method to estimate the severity of knee OA.

Ulnar hemimelia: a report of four cases.

Ulnar hemimelia is a very rare skeletal abnormality characterized by the total or partial absence of the ulna. It is reported to occur in approximately 1 per 150,000 live births. Some shortening of the forearm, radial bowing, and tendency of the hand to drift to the ulnar side of the wrist usually accompany ulnar hemimelia. Other skeletal anomalies such as humeroradial synostosis, radial head dislocation, carpal or metacarpal coalition, and digital abnormalities may also be seen in cases of ulnar hemimelia. The patients may be asymptomatic in the presence of an isolated mild ulnar deficiency. On the other hand, cases of prominent ulnar deficiency accompanied by complex upper limb abnormalities leading to severe disability may also be observed. We herein present four patients with varying degrees of ulnar hemimelia. Our first case had an isolated ulnar hemimelia, whereas the other three had additional upper limb abnormalities of different types.