European Journal of Cardiovascular Medicine

The brainstem, which is located in the posterior fossa, is an important link between the brain and the spinal cord. It is made up of the midbrain, pons, and medulla oblongata, and it contains cranial nerves III to XII. The brainstem is more than just a connecting conduit; it also controls important life-sustaining functions like breathing and heart rate, arousal, and consciousness. As a result, lesions in this little but very crucial area often cause clinical symptoms that are much worse than expected, even when the lesion is not very big [1-3].
Brainstem lesions have a lot of different causes. Ischemic infarcts are the most prevalent type, making for about 10–15% of all strokes. Other reasons include bleeding, tumors like gliomas, disorders that damage the myelin sheath, infections, blood vessel problems, traumatic brain injury, central pontine myelinolysis, and neurodegenerative diseases such progressive supranuclear palsy and multisystem atrophy. The clinical manifestations of these lesions exhibit significant variability, indicative of the dense aggregation of motor, sensory, cranial nerve, and autonomic pathways within the brainstem. For example, patients may show signs of hemiparesis, cranial nerve palsies, ataxia, dysarthria, oculomotor problems, or complicated brainstem syndromes [4-6].
Neuroimaging, especially magnetic resonance imaging (MRI), has changed the way brainstem lesions are diagnosed by letting doctors see anatomical structures and pathological alterations in great detail. Imaging not only helps identify distinct causes, but it is also very important for planning treatment and making predictions about the future. Despite these advancements, literature regarding the thorough assessment of the etiological range, clinical profiles, and imaging characteristics of brainstem lesions is still rather few, especially within the Indian setting [7, 8]. In this context, the current study was conducted to examine the incidence, clinical presentation, and imaging features of brainstem lesions in patients admitted to a tertiary care teaching hospital. By outlining the patterns of disease and linking them to clinical characteristics, the study seeks to augment comprehension of brainstem pathology and provide enhanced diagnostic and therapeutic approaches [9-11].

The Department of Neurology at Nandyal Government Medical College and its affiliated teaching hospital in Andhra Pradesh, India, did this study. It was a prospective observational study. The trial commenced between June 2024 and May 2025 and encompassed patients admitted with symptoms indicative of brainstem involvement. During the trial period, 22 patients who met the criteria for inclusion were enrolled in the study. All patients over 18 years old who were admitted to the neurology ward and intensive care unit (ICU) with clinical signs of brainstem lesions were screened and assessed.

Inclusion Criteria:

• Adult patients (≥18 years) with clinical evidence of brainstem syndrome.
• Patients who provided informed consent to participate in the study.

Exclusion Criteria:

• Patients with simultaneous isolated cerebellar or supratentorial lesions.
• Patients who did not provide consent.

Data Collection:

A comprehensive clinical history was acquired, encompassing demographic information (age, sex), risk factors (hypertension, diabetes, smoking, alcohol consumption), and presenting symptoms. A thorough neurological examination was conducted to pinpoint the lesion inside the brainstem (midbrain, pons, or medulla).

A total of 22 patients with brainstem lesions who fulfilled the inclusion criteria were enrolled in the study. The results are presented below in terms of etiology, demographic distribution, anatomical localization, and clinical presentation.

Table 1: Etiological Spectrum of Brainstem Lesions

Brainstem infarcts were the leading cause, making up 77.3% (17/22) of the cases. Other causes included pontine bleed (4.5%), pontine glioma (4.5%), demyelination (4.5%), and degenerative diseases (9%). Males (16/22, 72.7%) were more commonly affected than females (6/22, 27.3%).

Table 2: Age Distribution According to Etiology

The age group of 60 to 69 years old was the most afflicted, with 11 cases (50%). Infarcts were prevalent among middle-aged and elderly patients, whereas degenerative diseases were restricted to the 60–69 years cohort. There was only one occurrence of demyelination in the 40–49 years group, and there was only one tumor (pontine glioma) in a patient aged 60–69 years.

Table 3: Anatomical Distribution of Brainstem Lesions

The pons was the site that was most often implicated (11 cases), followed by the midbrain (7 cases) and the medulla (3 cases). Infarcts were the most prevalent type of damage in all three areas, with the pons being the most common place for them to happen. The degenerative lesions were limited to the midbrain, but the solitary hemorrhage and tumor were restricted to the pons.

Table 4: Clinical Presentations of Brainstem Lesions

Infarcts were the primary etiology of brainstem lesions, with a male predominance and a peak prevalence within the 60–69 year age cohort. The pons was the anatomical region most frequently impacted. Clinical aspects exhibited a robust correlation with lesion localization and etiology, characterized by specific brainstem syndromes in infarcts and unique patterns in hemorrhagic, neoplastic, demyelinating, and degenerative lesions.

Fg1: Left Pontine infarct

Fg2: Left Pontine infarct

Fg3: Left Pontine infarct

Fg4: Left Pontine infarct

Fg5: Left Lateral Medullary Infarct

Fg6: Left Lateral Medullary Infarct

Fg7: Left hemi Pontine infarct

Fg8: Left hemi Pontine infarct

Fg9: Left hemi Pontine infarct

Fg10: Pontine Glioma.

In this investigation, we assessed the etiological spectrum, clinical symptoms, and imaging characteristics of brainstem lesions in a cohort of 22 individuals.  The results confirm the intricacy of brainstem pathology and its unequal clinical significance, considering the dense organization of essential nuclei and fiber networks in this area.  Infarcts were identified as the predominant etiology, including over three-quarters of cases, aligning with existing research that links 10–15% of all ischemic strokes to the brainstem [10-12].  The elevated incidence of infarcts identified in our investigation may be associated with the prevalence of vascular risk factors, including hypertension and diabetes, among the examined population.  Other causes, such as pontine hemorrhage, glioma, demyelination, and degenerative illnesses, were relatively rare, but it is vital to know about them in order to make the right diagnosis [13-15].

 The age distribution indicated that most patients were in their sixties, and there were more men than women.  This observation aligns with global trends in stroke epidemiology, wherein growing age and male gender are recognized risk factors.  A single instance of demyelination was identified in a younger demographic, highlighting the potential for inflammatory or autoimmune etiologies in certain patients.  Degenerative illnesses impacting the brainstem were limited to older adults, aligning with the normal progression of progressive neurodegenerative diseases such progressive supranuclear palsy [15-17].

 Anatomical localization in our investigation indicated that the pons was the most often damaged location, followed by the midbrain and medulla. This distribution is well documented in prior papers, as the pons is extremely sensitive to ischemia due to its circulatory supply from perforating branches of the basilar artery.  The clinical characteristics in our series mirrored the underlying anatomical involvement [18, 19].  Pontine infarcts manifested with dysarthria, facial palsy, hemiplegia, and classical syndromes such as Millard-Gubler and one-and-a-half syndrome, whereas midbrain infarcts were linked to Weber’s and Benedict syndromes and vertical gaze palsy.  The solitary pontine hemorrhage resulted in quadriparesis accompanied by compromised ocular movements, while the glioma presented with intense headache and dizziness, symptoms indicative of elevated intracranial pressure.  Demyelination manifested as isolated dysarthria, while degenerative instances were marked by escalating clumsiness and extrapyramidal symptoms.  These results show how closely clinical evaluation and neuroimaging are related when it comes to determining both the location of a lesion and its cause [20, 21].

 The findings of our investigation align with other reports that highlight the diagnostic difficulties associated with brainstem lesions due to their diverse and overlapping manifestations.  Previous research conducted by Ortiz de Mendivil and associates has demonstrated that brainstem strokes can resemble other posterior fossa lesions, underscoring the significance of sophisticated imaging techniques.  Hirsch and colleagues similarly illustrated the utility of MRI in differentiating vascular, demyelinating, and neoplastic lesions.  Our results confirm previous findings, emphasizing MRI as the preferred imaging technique for assessing brainstem disease [21, 22].

 Even if the study gives us useful information, we need to be aware of some of its flaws.  The sample size was comparatively limited and sourced from a single tertiary care facility, constraining the generalizability of the results.  Long-term outcomes and prognostic associations were not examined, which could elucidate the disease load and recovery.  Future investigations should focus on including larger multicentric populations and utilizing modern imaging techniques, such as diffusion tensor imaging and functional MRI, to improve our comprehension of structural and functional correlations in brainstem pathology [22, 23].

This work elucidates the varied etiological spectrum, clinical manifestations, and imaging characteristics of brainstem lesions in a cohort of patients from a tertiary care hospital.  Infarcts were recognized as the predominant cause, with a distinct male predominance and a peak occurrence during the sixth decade of life.  The pons was the anatomical site most commonly damaged, succeeded by the midbrain and medulla.  Clinical presentations exhibited a robust correlation with lesion localization, characterized by specific brainstem syndromes in vascular lesions and unique symptoms in hemorrhagic, neoplastic, demyelinating, and degenerative illnesses.  Magnetic resonance imaging was crucial for precisely identifying lesions and differentiating among various causes.  The results of this study highlight the necessity of combining meticulous clinical assessment with sophisticated neuroimaging to facilitate prompt diagnosis, inform suitable management, and enhance patient outcomes.

Funding:

None

Conflict of Intertest:

None.

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